A device that substitutes for a heart valve. It may be composed of biological material (BIOPROSTHESIS) and/or synthetic material.
Surgical insertion of cylindric hydraulic devices for the treatment of organic ERECTILE DYSFUNCTION.
Rigid, semi-rigid, or inflatable cylindric hydraulic devices, with either combined or separate reservoir and pumping systems, implanted for the surgical treatment of organic ERECTILE DYSFUNCTION.
Surgical insertion of synthetic material to repair injured or diseased heart valves.
The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle.
Flaps of tissue that prevent regurgitation of BLOOD from the HEART VENTRICLES to the HEART ATRIA or from the PULMONARY ARTERIES or AORTA to the ventricles.
Surgical insertion of an appliance for the replacement of areas of the mandible.
Prosthesis, usually heart valve, composed of biological material and whose durability depends upon the stability of the material after pretreatment, rather than regeneration by host cell ingrowth. Durability is achieved 1, mechanically by the interposition of a cloth, usually polytetrafluoroethylene, between the host and the graft, and 2, chemically by stabilization of the tissue by intermolecular linking, usually with glutaraldehyde, after removal of antigenic components, or the use of reconstituted and restructured biopolymers.
Surgical insertion of an appliance for the replacement of areas of the maxilla, mandible, and face. When only portions of the mandible are replaced, it is referred to as MANDIBULAR PROSTHESIS IMPLANTATION.
Obstruction of a blood vessel (embolism) by a blood clot (THROMBUS) in the blood stream.
Pathological conditions involving any of the various HEART VALVES and the associated structures (PAPILLARY MUSCLES and CHORDAE TENDINEAE).
The valve between the left atrium and left ventricle of the heart.
The inability in the male to have a PENILE ERECTION due to psychological or organ dysfunction.
The plan and delineation of prostheses in general or a specific prosthesis.
The external reproductive organ of males. It is composed of a mass of erectile tissue enclosed in three cylindrical fibrous compartments. Two of the three compartments, the corpus cavernosa, are placed side-by-side along the upper part of the organ. The third compartment below, the corpus spongiosum, houses the urethra.
Agents that prevent clotting.
A pathological constriction that can occur above (supravalvular stenosis), below (subvalvular stenosis), or at the AORTIC VALVE. It is characterized by restricted outflow from the LEFT VENTRICLE into the AORTA.
Malfunction of implantation shunts, valves, etc., and prosthesis loosening, migration, and breaking.
Pathological condition characterized by the backflow of blood from the ASCENDING AORTA back into the LEFT VENTRICLE, leading to regurgitation. It is caused by diseases of the AORTIC VALVE or its surrounding tissue (aortic root).
The hollow, muscular organ that maintains the circulation of the blood.
Surgical insertion of a prosthesis.
Artificial substitutes for body parts, and materials inserted into tissue for functional, cosmetic, or therapeutic purposes. Prostheses can be functional, as in the case of artificial arms and legs, or cosmetic, as in the case of an artificial eye. Implants, all surgically inserted or grafted into the body, tend to be used therapeutically. IMPLANTS, EXPERIMENTAL is available for those used experimentally.
The valve consisting of three cusps situated between the right atrium and right ventricle of the heart.
Prostheses used to partially or totally replace a human or animal joint. (from UMDNS, 1999)
Backflow of blood from the LEFT VENTRICLE into the LEFT ATRIUM due to imperfect closure of the MITRAL VALVE. This can lead to mitral valve regurgitation.
A valve situated at the entrance to the pulmonary trunk from the right ventricle.
Inflammation of the ENDOCARDIUM caused by BACTERIA that entered the bloodstream. The strains of bacteria vary with predisposing factors, such as CONGENITAL HEART DEFECTS; HEART VALVE DISEASES; HEART VALVE PROSTHESIS IMPLANTATION; or intravenous drug use.
Replacement for a knee joint.
Replacement for a hip joint.
Graphic registration of the heart sounds picked up as vibrations and transformed by a piezoelectric crystal microphone into a varying electrical output according to the stresses imposed by the sound waves. The electrical output is amplified by a stethograph amplifier and recorded by a device incorporated into the electrocardiograph or by a multichannel recording machine.
Narrowing of the passage through the MITRAL VALVE due to FIBROSIS, and CALCINOSIS in the leaflets and chordal areas. This elevates the left atrial pressure which, in turn, raises pulmonary venous and capillary pressure leading to bouts of DYSPNEA and TACHYCARDIA during physical exertion. RHEUMATIC FEVER is its primary cause.
Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.
A repeat operation for the same condition in the same patient due to disease progression or recurrence, or as followup to failed previous surgery.
System established by the World Health Organization and the International Committee on Thrombosis and Hemostasis for monitoring and reporting blood coagulation tests. Under this system, results are standardized using the International Sensitivity Index for the particular test reagent/instrument combination used.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus.
Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.
The co-occurrence of pregnancy and a cardiovascular disease. The disease may precede or follow FERTILIZATION and it may or may not have a deleterious effect on the pregnant woman or FETUS.
Removal of an implanted therapeutic or prosthetic device.
A disorder characterized by sudden attacks of respiratory distress in at rest patients with HEART FAILURE and PULMONARY EDEMA. It usually occurs at night after several hours of sleep in a reclining position. Patients awaken with a feeling of suffocation, coughing, a cold sweat, and TACHYCARDIA. When there is significant WHEEZING, it is called cardiac asthma.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
Artificial device such as an externally-worn camera attached to a stimulator on the RETINA, OPTIC NERVE, or VISUAL CORTEX, intended to restore or amplify vision.
Formation and development of a thrombus or blood clot in the blood vessel.
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
Prosthetic replacements for arms, legs, and parts thereof.
An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.
Elements of limited time intervals, contributing to particular results or situations.
The fitting and adjusting of artificial parts of the body. (From Stedman's, 26th ed)
Measurement of intracardiac blood flow using an M-mode and/or two-dimensional (2-D) echocardiogram while simultaneously recording the spectrum of the audible Doppler signal (e.g., velocity, direction, amplitude, intensity, timing) reflected from the moving column of red blood cells.
Inflammation of the inner lining of the heart (ENDOCARDIUM), the continuous membrane lining the four chambers and HEART VALVES. It is often caused by microorganisms including bacteria, viruses, fungi, and rickettsiae. Left untreated, endocarditis can damage heart valves and become life-threatening.
Medical devices which substitute for a nervous system function by electrically stimulating the nerves directly and monitoring the response to the electrical stimulation.
Abnormal protrusion or billowing of one or both of the leaflets of MITRAL VALVE into the LEFT ATRIUM during SYSTOLE. This allows the backflow of blood into left atrium leading to MITRAL VALVE INSUFFICIENCY; SYSTOLIC MURMURS; or CARDIAC ARRHYTHMIA.
An implant used to replace one or more of the ear ossicles. They are usually made of plastic, Gelfoam, ceramic, or stainless steel.
A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (VENTRICULAR DYSFUNCTION), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as MYOCARDIAL INFARCTION.
An artificial replacement for one or more natural teeth or part of a tooth, or associated structures, ranging from a portion of a tooth to a complete denture. The dental prosthesis is used for cosmetic or functional reasons, or both. DENTURES and specific types of dentures are also available. (From Boucher's Clinical Dental Terminology, 4th ed, p244 & Jablonski, Dictionary of Dentistry, 1992, p643)
Surgical insertion of BLOOD VESSEL PROSTHESES to repair injured or diseased blood vessels.
Flaps within the VEINS that allow the blood to flow only in one direction. They are usually in the medium size veins that carry blood to the heart against gravity.
Infections resulting from the implantation of prosthetic devices. The infections may be acquired from intraoperative contamination (early) or hematogenously acquired from other sites (late).
Backflow of blood from the RIGHT VENTRICLE into the RIGHT ATRIUM due to imperfect closure of the TRICUSPID VALVE.
Pathological conditions involving the HEART including its structural and functional abnormalities.
Developmental abnormalities involving structures of the heart. These defects are present at birth but may be discovered later in life.
Device constructed of either synthetic or biological material that is used for the repair of injured or diseased blood vessels.
Generating tissue in vitro for clinical applications, such as replacing wounded tissues or impaired organs. The use of TISSUE SCAFFOLDING enables the generation of complex multi-layered tissues and tissue structures.
A prosthesis that gains its support, stability, and retention from a substructure that is implanted under the soft tissues of the basal seat of the device and is in contact with bone. (From Boucher's Clinical Dental Terminology, 4th ed)
Delay in the attachment and implantation of BLASTOCYST to the uterine ENDOMETRIUM. The blastocyst remains unattached beyond the normal duration thus delaying embryonic development.
Pathologic deposition of calcium salts in tissues.
Surgical insertion of an electronic hearing device (COCHLEAR IMPLANTS) with electrodes to the COCHLEAR NERVE in the inner ear to create sound sensation in patients with residual nerve fibers.
'Amputee' is a medical term used to describe an individual who has undergone the surgical removal of a limb or extremity, such as an arm, leg, foot, or hand, due to various reasons like trauma, disease, or congenital defects.
A device, activated electronically or by expired pulmonary air, which simulates laryngeal activity and enables a laryngectomized person to speak. Examples of the pneumatic mechanical device are the Tokyo and Van Hunen artificial larynges. Electronic devices include the Western Electric electrolarynx, Tait oral vibrator, Cooper-Rand electrolarynx and the Ticchioni pipe.
Partial or total replacement of a joint.
Implants constructed of materials designed to be absorbed by the body without producing an immune response. They are usually composed of plastics and are frequently used in orthopedics and orthodontics.
A prosthetic appliance for the replacement of areas of the maxilla, mandible, and face, missing as a result of deformity, disease, injury, or surgery. When the prosthesis replaces portions of the mandible only, it is referred to as MANDIBULAR PROSTHESIS.
A ready-made or custom-made prosthesis of glass or plastic shaped and colored to resemble the anterior portion of a normal eye and used for cosmetic reasons. It is attached to the anterior portion of an orbital implant (ORBITAL IMPLANTS) which is placed in the socket of an enucleated or eviscerated eye. (From Dorland, 28th ed)
A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
The transference of a heart from one human or animal to another.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.

Animal experimental implantation of an atrial septal defect occluder system. (1/2034)

OBJECTIVE: To establish the implantation technique for the atrial septal defect occluder system (ASDOS) device in an experimental animal model and to determine long term mechanical stability of the device and its in vivo properties in terms of biocompatibility and tissue reaction. MATERIALS AND METHODS: An atrial septal defect was created and the device implanted in 17 pigs (mean weight 30 kg). The implantation technique was refined and modified because of initial technical and anatomical complications during nine acute pilot studies. The technique proved to be feasible in eight subsequent survival studies. Four pigs were electively killed three months after implantation (group 1). The remaining four pigs were killed six months after implantation (group 2). RESULTS: Necropsy showed all devices were embedded in soft tissue three months after implantation. Microscopic examination of atrial septal tissue showed an acute granulomatous inflammatory reaction in group 1 and fibrosis in group 2. The intensity of the inflammatory reaction around the device was clearly milder in group 2, indicating a decline in the inflammatory response with time. Clinical and biochemical investigations indicated acceptable biocompatibility of the device. CONCLUSION: The implantation technique for the ASDOS device in a chronic pig model has been established. Biocompatibility of the device was acceptable.  (+info)

Bileaflet mechanical prostheses for aortic valve replacement in patients younger than 65 years and 65 years of age or older: major thromboembolic and hemorrhagic complications. (2/2034)

OBJECTIVE: To determine major thromboembolic and hemorrhagic complications and predictive risk factors associated with aortic valve replacement (AVR), using bileaflet mechanical prostheses (CarboMedics and St. Jude Medical). DESIGN: A case series. SETTING: Cardiac surgical services at the teaching institutions of the University of British Columbia. PATIENTS AND METHODS: Patients 2 age groups who had undergone AVR between 1989 and 1994 were studied. Group 1 comprised 384 patients younger than 65 years. Group 2 comprised 215 patients 65 years of age and older. RESULTS: The linearized rates of major thromboembolism (TE) occurring after AVR were 1.54%/patient-year for group 1 and 3.32%/patient-year for group 2; the rates for major TE occurring more than 30 days after AVR were 1.13%/patient-year for group 1 and 1.55%/patient-year for group 2. The crude rates for major TE occurring within 30 days of AVR were 1.04% for group 1 and 3.72% for group 2. The death rate from major TE in group 1 was 0.31%/patient-year and in group 2 was 0.88%/patient-year. Of the major TE events occurring within 30 days, 100% of patients in both age groups were inadequately anticoagulated at the time of the event, and for events occurring more than 30 days after AVR, 45% in group 1 and 57% in group 2 were inadequately anticoagulated (INR less than 2.0). The overall linearized rates of major hemorrhage were 1.54%/patient-year for group 1 and 2.21%/patient-year for group 2. There were no cases of prosthesis thrombosis in either group. The mean (and standard error) overall freedom from major TE for group 1 patients at 5 years was 95.6% (1.4%) and with exclusion of early events was 96.7% (1.3%); for group 2 patients the rates were 90.0% (3.2%) and 93.7% (3.0%), respectively. The mean (and SE) overall freedom from major and fatal TE and hemorrhage for group 1 patients was 90.1% (2.3%) and with exclusion of early events was 91.2% (2.3%); for group 2 patients the rates were 87.9% (3.1%) and 92.5% (2.9%), respectively. The 5-year rate for freedom from valve-related death for group 1 patients was 96.3% (2.1%) and for group 2 patients was 97.2% (1.2%). CONCLUSION: The thromboembolic and hemorrhagic complications after AVR with bileaflet mechanical prostheses occur more frequently and result in more deaths in patients 65 years of age and older than in patients years younger than 65 years.  (+info)

Minimally invasive aortic valve replacement through a transverse sternotomy: a word of caution. (3/2034)

OBJECTIVES: To compare aortic valve replacement (AVR) using a minimally invasive approach through a transverse sternotomy with the established approach of median sternotomy. DESIGN: Retrospective, case-control study. PATIENTS: Fourteen high risk patients (median age 78, Parsonnet score of 18%) who underwent AVR performed through a minimally invasive transverse sternotomy were compared with a historical group of patients matched for age, sex, and Parsonnet score who underwent AVR performed through a median sternotomy by the same surgeon. OUTCOME MEASURES: Cross clamp time, total bypass time, intensive care stay, postoperative in-hospital stay, morbidity, and mortality. RESULTS: There were two deaths in the minimally invasive group and none in the control group (NS). The cross clamp and total bypass times were longer in the minimally invasive group (67 and 92 minutes v 46 and 66 minutes, p < 0.001). There was a higher incidence of re-exploration for bleeding (14% v 0%) and paravalvar leaks (21% v 0%) in the minimally invasive group but these differences were not significant. The minimally invasive group had a longer postoperative in-hospital stay (p = 0.025). The incidence of mortality or major morbidity was 43% (six of 14) in the minimally invasive group and 7% (one of 14) in the matched pairs (p = 0.013). CONCLUSIONS: AVR can be performed through a transverse sternotomy but the operation takes longer and there is an unacceptably high incidence of morbidity and mortality.  (+info)

Perivalvular abscesses associated with endocarditis; clinical features and prognostic factors of overall survival in a series of 233 cases. Perivalvular Abscesses French Multicentre Study. (4/2034)

AIMS: The purposes of this study were to determine the clinical features and to identify prognostic factors of abscesses associated with infective endocarditis. METHODS AND RESULTS: During a 5-year period from January 1989, 233 patients with perivalvular abscesses associated with infective endocarditis were enrolled in a retrospective multicentre study. Of the patients, 213 received medical surgical therapy and 20 medical therapy alone. No causative microorganism could be identified in 31% of cases. Sensitivity for the detection of abscesses was 36 and 80%, respectively using transthoracic and transoesophageal echocardiography. Surgical treatment consisted of primary suture of the abscess (38%), insertion of a felt aortic or mitral ring using Teflon or pericardium (42%), or debridment of the abscess cavity (20%). The 1 month operative mortality was 16%. Actuarial rates for overall survival at 3 and 27 months in operated patients were 75 +/- 10% and 59 +/- 11%, respectively. Increasing patient age, staphylococcal infection, and fistulization of the abscess were found to be independent risk factors in both 1 month and overall operative mortality. Renal failure was a risk factor predictive of operative mortality at 1 month, whereas uncontrolled infection and circumferential abscess were regarded as risk factors predictive of overall operative mortality. CONCLUSION: The data determined prognostic factors of abscesses associated with infective endocarditis.  (+info)

Replacement of the aortic root in patients with Marfan's syndrome. (5/2034)

BACKGROUND: Replacement of the aortic root with a prosthetic graft and valve in patients with Marfan's syndrome may prevent premature death from rupture of an aneurysm or aortic dissection. We reviewed the results of this surgical procedure at 10 experienced surgical centers. METHODS: A total of 675 patients with Marfan's syndrome underwent replacement of the aortic root. Survival and morbidity-free survival curves were calculated, and risk factors were determined from a multivariable regression analysis. RESULTS: The 30-day mortality rate was 1.5 percent among the 455 patients who underwent elective repair, 2.6 percent among the 117 patients who underwent urgent repair (within 7 days after a surgical consultation), and 11.7 percent among the 103 patients who underwent emergency repair (within 24 hours after a surgical consultation). Of the 675 patients, 202 (30 percent) had aortic dissection involving the ascending aorta. Forty-six percent of the 158 adult patients with aortic dissection and a documented aortic diameter had an aneurysm with a diameter of 6.5 cm or less. There were 114 late deaths (more than 30 days after surgery); dissection or rupture of the residual aorta (22 patients) and arrhythmia (21 patients) were the principal causes of late death. The risk of death was greatest within the first 60 days after surgery, then rapidly decreased to a constant level by the end of the first year. CONCLUSIONS: Elective aortic-root replacement has a low operative mortality. In contrast, emergency repair, usually for acute aortic dissection, is associated with a much higher early mortality. Because nearly half the adult patients with aortic dissection had an aortic-root diameter of 6.5 cm or less at the time of operation, it may be prudent to undertake prophylactic repair of aortic aneurysms in patients with Marfan's syndrome when the diameter of the aorta is well below that size.  (+info)

Dose-dependent fetal complications of warfarin in pregnant women with mechanical heart valves. (6/2034)

OBJECTIVES: The purpose of this study was to assess the incidence of warfarin fetal complications and whether they are dose-dependent. BACKGROUND: Gravid patients with mechanical heart valves require long-term anticoagulant therapy. Controversy exists concerning the appropriate treatment of these patients. METHODS: Forty-three women on warfarin carrying out 58 pregnancies were studied. For each patient with full-term pregnancy a caesarian section was scheduled for the 38th week during brief warfarin discontinuation. Maternal and fetal complications were evaluated. Fetal complications were divided according to the warfarin dosage < or = 5 mg and > 5 mg necessary to keep an international normalized ratio (INR) of 2.5 to 3.5, and analyzed subsequently. RESULTS: A total of 58 pregnancies were observed: 31 healthy babies (30 full term, 1 premature) and 27 fetal complications (22 spontaneous abortions, 2 warfarin embryopathies, 1 stillbirth, 1 ventricular septal defect, 1 growth retardation) were recorded. Two maternal valve thromboses occurred. No fetal or maternal bleeding was observed during caesarian sections or premature vaginal delivery. Patients whose warfarin doses during pregnancy were > 5 mg had 22 fetal complications, whereas those taking a dose < or = 5 mg had only five fetal complications (p = 0.0001). For an increase of the warfarin dose there was a substantially increased probability of fetal complications (p < 0.0001; p < 0.7316). CONCLUSIONS: There is a close dependency between warfarin dosage and fetal complications. Patients on warfarin anticoagulation may be delivered by planned caesarian section at the 38th week while briefly interrupting anticoagulation.  (+info)

Acute renal failure following cardiac surgery. (7/2034)

BACKGROUND: Acute renal failure requiring dialysis (ARF-D) occurs in 1.5% of patients following cardiac surgery, and remains a cause of major morbidity and mortality. While some preoperative risk factors have been characterized, the influence of preoperative and intraoperative factors on the occurrence of ARF following cardiac surgery is less well understood. METHODS: Preoperative and intraoperative data on 2843 consecutive adult patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) from February 1, 1995 to February 1, 1997 were recorded and entered into a computerized database. Two definitions of renal failure were employed: (i) ARF defined as a rise in serum creatinine (Cr) of 1 mg/dl above baseline; and (ii) ARF-D defined as the development of ARF for which some form of dialytic therapy was required. The association between preoperative and intraoperative variables and the development of ARF was assessed by multivariate logistic regression. RESULTS: A total of 2672 of the 2844 patients underwent isolated coronary artery bypass grafting (CABG) surgery, the remaining 172 underwent valve surgery with or without bypass grafting. Of the CABG patients 7.9% developed ARF and 0.7% developed ARF-D. The mortality for patients who developed ARF was 14% (OR 15, P = 0.0001) compared with 1% among those who did not develop ARF. The mortality for CABG patients who developed ARF-D was 28% (OR 20, P = 0.0001) compared with 1.8% among those who did not require dialysis. Variables that were significantly associated with the development of ARF by multivariate analysis included: increased age, elevated preoperative serum Cr, duration of CPB, presence of a carotid artery bruit, presence of diabetes, reduced cardiac ejection fraction and increased body weight. Variables independently associated with ARF-D included serum Cr, duration of CPB, carotid artery bruit and presence of diabetes. The utility of these models for predicting the development of ARF and ARF-D was confirmed by bootstrapping techniques. Because of the small number of patients who underwent valve surgery, none of these variables were significantly associated with the development of ARF or ARF-D in this group of patients. CONCLUSION: The development of ARF or ARF-D is associated with a high mortality following CABG surgery. We have identified perioperative variables, which may be useful in stratifying risk for the development of ARF.  (+info)

The natural history of aortic valve disease after mitral valve surgery. (8/2034)

OBJECTIVES: The present study evaluates the long-term course of aortic valve disease and the need for aortic valve surgery in patients with rheumatic mitral valve disease who underwent mitral valve surgery. BACKGROUND: Little is known about the natural history of aortic valve disease in patients undergoing mitral valve surgery for rheumatic mitral valve disease. In addition there is no firm policy regarding the appropriate treatment of mild aortic valve disease while replacing the mitral valve. METHODS: One-hundred thirty-one patients (44 male, 87 female; mean age 61+/-13 yr, range 35 to 89) were followed after mitral valve surgery for a mean period of 13+/-7 years. All patients had rheumatic heart disease. Aortic valve function was assessed preoperatively by cardiac catheterization and during follow-up by transthoracic echocardiography. RESULTS: At the time of mitral valve surgery, 59 patients (45%) had mild aortic valve disease: 7 (5%) aortic stenosis (AS), 58 (44%) aortic regurgitation (AR). At the end of follow-up, 96 patients (73%) had aortic valve disease: 33 AS (mild or moderate except in two cases) and 90 AR (mild or moderate except in one case). Among patients without aortic valve disease at the time of the mitral valve surgery, only three patients developed significant aortic valve disease after 25 years of follow-up procedures. Disease progression was noted in three of the seven patients with AS (2 to severe) and in six of the fifty eight with AR (1 to severe). Fifty two (90%) with mild AR remained stable after a mean follow-up period of 16 years. In only three patients (2%) the aortic valve disease progressed significantly after 9, 17 and 22 years. In only six patients of the entire cohort (5%), aortic valve replacement was needed after a mean period of 21 years (range 15 to 33). In four of them the primary indication for the second surgery was dysfunction of the prosthetic mitral valve. CONCLUSIONS: Our findings indicate that, among patients with rheumatic heart disease, a considerable number of patients have mild aortic valve disease at the time of mitral valve surgery. Yet most do not progress to severe disease, and aortic valve replacement is rarely needed after a long follow-up period. Thus, prophylactic valve replacement is not indicated in these cases.  (+info)

A heart valve prosthesis is a medical device that is implanted in the heart to replace a damaged or malfunctioning heart valve. The prosthetic valve can be made of biological tissue (such as from a pig or cow) or artificial materials (such as carbon or polyester). Its function is to allow for the proper directional flow of blood through the heart, opening and closing with each heartbeat to prevent backflow of blood.

There are several types of heart valve prostheses, including:

1. Mechanical valves: These are made entirely of artificial materials and have a longer lifespan than biological valves. However, they require the patient to take blood-thinning medication for the rest of their life to prevent blood clots from forming on the valve.
2. Bioprosthetic valves: These are made of biological tissue and typically last 10-15 years before needing replacement. They do not require the patient to take blood-thinning medication, but there is a higher risk of reoperation due to degeneration of the tissue over time.
3. Homografts or allografts: These are human heart valves that have been donated and preserved for transplantation. They have similar longevity to bioprosthetic valves and do not require blood-thinning medication.
4. Autografts: In this case, the patient's own pulmonary valve is removed and used to replace the damaged aortic valve. This procedure is called the Ross procedure and has excellent long-term results, but it requires advanced surgical skills and is not widely available.

The choice of heart valve prosthesis depends on various factors, including the patient's age, overall health, lifestyle, and personal preferences.

Penile implantation, also known as a prosthetic penis or penile prosthesis, is a surgical procedure to place devices into the penis to help a person with erectile dysfunction (ED) achieve an erection. The two main types of penile implants are inflatable and semi-rigid rods.

The inflatable implant consists of a fluid-filled reservoir, a pump, and two or three inflatable cylinders in the penis. The semi-rigid rod implant is a pair of flexible rods that are bent into an erect position for sexual intercourse and can be straightened when not in use.

Penile implantation is typically considered as a last resort treatment option for ED, when other treatments such as medications, vacuum constriction devices, or penile injections have failed or are not suitable. The procedure is typically performed by a urologist under general or spinal anesthesia and requires a hospital stay of one to two days.

It's important to note that like any surgical procedure, penile implantation also has risks such as infection, bleeding, mechanical failure, and device malfunction. It is essential for patients to discuss the potential benefits and risks with their healthcare provider before making a decision about this treatment option.

A penile prosthesis is a medical device that is implanted inside the penis to treat erectile dysfunction. It consists of a pair of inflatable or semi-rigid rods, which are surgically placed into the corpora cavernosa (the two sponge-like areas inside the penis that fill with blood to create an erection). The implant allows the person with ED to have a controlled and manual erection suitable for sexual intercourse. This is usually considered as a last resort when other treatments, such as medications or vacuum devices, have failed.

Heart valve prosthesis implantation is a surgical procedure where an artificial heart valve is inserted to replace a damaged or malfunctioning native heart valve. This can be necessary for patients with valvular heart disease, including stenosis (narrowing) or regurgitation (leaking), who do not respond to medical management and are at risk of heart failure or other complications.

There are two main types of artificial heart valves used in prosthesis implantation: mechanical valves and biological valves. Mechanical valves are made of synthetic materials, such as carbon and metal, and can last a long time but require lifelong anticoagulation therapy to prevent blood clots from forming. Biological valves, on the other hand, are made from animal or human tissue and typically do not require anticoagulation therapy but may have a limited lifespan and may need to be replaced in the future.

The decision to undergo heart valve prosthesis implantation is based on several factors, including the patient's age, overall health, type and severity of valvular disease, and personal preferences. The procedure can be performed through traditional open-heart surgery or minimally invasive techniques, such as robotic-assisted surgery or transcatheter aortic valve replacement (TAVR). Recovery time varies depending on the approach used and individual patient factors.

The aortic valve is the valve located between the left ventricle (the lower left chamber of the heart) and the aorta (the largest artery in the body, which carries oxygenated blood from the heart to the rest of the body). It is made up of three thin flaps or leaflets that open and close to regulate blood flow. During a heartbeat, the aortic valve opens to allow blood to be pumped out of the left ventricle into the aorta, and then closes to prevent blood from flowing back into the ventricle when it relaxes. Any abnormality or damage to this valve can lead to various cardiovascular conditions such as aortic stenosis, aortic regurgitation, or infective endocarditis.

Heart valves are specialized structures in the heart that ensure unidirectional flow of blood through its chambers during the cardiac cycle. There are four heart valves: the tricuspid valve and the mitral (bicuspid) valve, located between the atria and ventricles, and the pulmonic (pulmonary) valve and aortic valve, located between the ventricles and the major blood vessels leaving the heart.

The heart valves are composed of thin flaps of tissue called leaflets or cusps, which are supported by a fibrous ring. The aortic and pulmonic valves have three cusps each, while the tricuspid and mitral valves have three and two cusps, respectively.

The heart valves open and close in response to pressure differences across them, allowing blood to flow forward into the ventricles during diastole (filling phase) and preventing backflow of blood into the atria during systole (contraction phase). A properly functioning heart valve ensures efficient pumping of blood by the heart and maintains normal blood circulation throughout the body.

Mandibular prosthesis implantation is a dental surgical procedure that involves the placement of dental implants into the mandible (lower jawbone) to support and retain a prosthetic restoration, such as a denture or fixed bridge. This procedure is typically performed to restore oral function, aesthetics, and quality of life for patients who have lost all or most of their natural lower teeth due to injury, decay, or other reasons.

The implantation process typically involves several steps. First, the dental surgeon will carefully evaluate the patient's jawbone density and overall oral health to determine if they are a good candidate for the procedure. If so, the surgeon will then place one or more titanium implants into the mandible, using specialized surgical techniques to ensure proper placement and alignment.

After the implant(s) have been placed, the patient will typically undergo a healing period of several months, during which time the jawbone will gradually fuse with the implant(s) in a process called osseointegration. Once this process is complete, the surgeon will attach an abutment to each implant, which will serve as a connector between the implant and the prosthetic restoration.

Finally, the dental prosthesis (such as a denture or bridge) will be fabricated and attached to the abutments, providing a stable and secure replacement for the missing teeth. With proper care and maintenance, mandibular prosthesis implantation can provide a long-lasting and effective solution for patients with significant tooth loss.

A bioprosthesis is a type of medical implant that is made from biological materials, such as heart valves or tendons taken from animals (xenografts) or humans (allografts). These materials are processed and sterilized to be used in surgical procedures to replace damaged or diseased tissues in the body.

Bioprosthetic implants are often used in cardiac surgery, such as heart valve replacement, because they are less likely to cause an immune response than synthetic materials. However, they may have a limited lifespan due to calcification and degeneration of the biological tissue over time. Therefore, bioprosthetic implants may need to be replaced after several years.

Bioprostheses can also be used in other types of surgical procedures, such as ligament or tendon repair, where natural tissue is needed to restore function and mobility. These prostheses are designed to mimic the properties of native tissues and provide a more physiological solution than synthetic materials.

Maxillofacial prosthesis implantation is a medical procedure that involves the surgical placement of osseointegrated implants (fixtures that are integrated into the bone) to support and retain a custom-made maxillofacial prosthesis. This type of prosthesis is designed to replace all or part of the facial structures, such as the eyes, nose, ears, or jaw, which may be missing due to congenital defects, trauma, or cancer resection.

The implantation procedure typically involves several steps:

1. Pre-surgical planning: This includes taking detailed measurements and creating a custom-made surgical guide based on the patient's anatomy.
2. Surgical placement of implants: The surgeon uses the surgical guide to place the implants in the bone at precise locations and angles.
3. Healing period: After the surgery, the implants are allowed to heal and integrate with the bone for several months.
4. Prosthesis fabrication: Once the implants have integrated, an impression is taken of the implant abutments (the parts that protrude through the gums) and a custom-made prosthesis is created.
5. Delivery of the prosthesis: The prosthesis is attached to the implant abutments using screws or other attachments.

Maxillofacial prosthesis implantation can significantly improve the patient's quality of life by restoring facial function, appearance, and speech. However, it requires careful planning, surgical skill, and close collaboration between the surgeon, prosthodontist, and patient.

Thromboembolism is a medical condition that refers to the obstruction of a blood vessel by a thrombus (blood clot) that has formed elsewhere in the body and then been transported by the bloodstream to a narrower vessel, where it becomes lodged. This process can occur in various parts of the body, leading to different types of thromboembolisms:

1. Deep Vein Thrombosis (DVT): A thrombus forms in the deep veins, usually in the legs or pelvis, and then breaks off and travels to the lungs, causing a pulmonary embolism.
2. Pulmonary Embolism (PE): A thrombus formed elsewhere, often in the deep veins of the legs, dislodges and travels to the lungs, blocking one or more pulmonary arteries. This can lead to shortness of breath, chest pain, and potentially life-threatening complications if not treated promptly.
3. Cerebral Embolism: A thrombus formed in another part of the body, such as the heart or carotid artery, dislodges and travels to the brain, causing a stroke or transient ischemic attack (TIA).
4. Arterial Thromboembolism: A thrombus forms in an artery and breaks off, traveling to another part of the body and blocking blood flow to an organ or tissue, leading to potential damage or loss of function. Examples include mesenteric ischemia (intestinal damage due to blocked blood flow) and retinal artery occlusion (vision loss due to blocked blood flow in the eye).

Prevention, early detection, and appropriate treatment are crucial for managing thromboembolism and reducing the risk of severe complications.

Heart valve diseases are a group of conditions that affect the function of one or more of the heart's four valves (tricuspid, pulmonic, mitral, and aortic). These valves are responsible for controlling the direction and flow of blood through the heart. Heart valve diseases can cause the valves to become narrowed (stenosis), leaky (regurgitation or insufficiency), or improperly closed (prolapse), leading to disrupted blood flow within the heart and potentially causing symptoms such as shortness of breath, fatigue, chest pain, and irregular heart rhythms. The causes of heart valve diseases can include congenital defects, age-related degenerative changes, infections, rheumatic heart disease, and high blood pressure. Treatment options may include medications, surgical repair or replacement of the affected valve(s), or transcatheter procedures.

The mitral valve, also known as the bicuspid valve, is a two-leaflet valve located between the left atrium and left ventricle in the heart. Its function is to ensure unidirectional flow of blood from the left atrium into the left ventricle during the cardiac cycle. The mitral valve consists of two leaflets (anterior and posterior), the chordae tendineae, papillary muscles, and the left atrial and ventricular myocardium. Dysfunction of the mitral valve can lead to various heart conditions such as mitral regurgitation or mitral stenosis.

Erectile dysfunction (ED) is the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. It can have physical and psychological causes, such as underlying health conditions like diabetes, heart disease, obesity, and mental health issues like stress, anxiety, and depression. ED can also be a side effect of certain medications. Treatment options include lifestyle changes, medication, counseling, and in some cases, surgery.

Prosthesis design is a specialized field in medical device technology that involves creating and developing artificial substitutes to replace a missing body part, such as a limb, tooth, eye, or internal organ. The design process typically includes several stages: assessment of the patient's needs, selection of appropriate materials, creation of a prototype, testing and refinement, and final fabrication and fitting of the prosthesis.

The goal of prosthesis design is to create a device that functions as closely as possible to the natural body part it replaces, while also being comfortable, durable, and aesthetically pleasing for the patient. The design process may involve collaboration between medical professionals, engineers, and designers, and may take into account factors such as the patient's age, lifestyle, occupation, and overall health.

Prosthesis design can be highly complex, particularly for advanced devices such as robotic limbs or implantable organs. These devices often require sophisticated sensors, actuators, and control systems to mimic the natural functions of the body part they replace. As a result, prosthesis design is an active area of research and development in the medical field, with ongoing efforts to improve the functionality, comfort, and affordability of these devices for patients.

The penis is a part of the male reproductive and urinary systems. It has three parts: the root, the body, and the glans. The root attaches to the pelvic bone and the body makes up the majority of the free-hanging portion. The glans is the cone-shaped end that protects the urethra, the tube inside the penis that carries urine from the bladder and semen from the testicles.

The penis has a dual function - it acts as a conduit for both urine and semen. During sexual arousal, the penis becomes erect when blood fills two chambers inside its shaft. This process is facilitated by the relaxation of the smooth muscles in the arterial walls and the trappping of blood in the corpora cavernosa. The stiffness of the penis enables sexual intercourse. After ejaculation, or when the sexual arousal passes, the muscles contract and the blood flows out of the penis back into the body, causing it to become flaccid again.

The foreskin, a layer of skin that covers the glans, is sometimes removed in a procedure called circumcision. Circumcision is often performed for religious or cultural reasons, or as a matter of family custom. In some countries, it's also done for medical reasons, such as to treat conditions like phimosis (an inability to retract the foreskin) or balanitis (inflammation of the glans).

It's important to note that any changes in appearance, size, or function of the penis should be evaluated by a healthcare professional, as they could indicate an underlying medical condition.

Anticoagulants are a class of medications that work to prevent the formation of blood clots in the body. They do this by inhibiting the coagulation cascade, which is a series of chemical reactions that lead to the formation of a clot. Anticoagulants can be given orally, intravenously, or subcutaneously, depending on the specific drug and the individual patient's needs.

There are several different types of anticoagulants, including:

1. Heparin: This is a naturally occurring anticoagulant that is often used in hospitalized patients who require immediate anticoagulation. It works by activating an enzyme called antithrombin III, which inhibits the formation of clots.
2. Low molecular weight heparin (LMWH): LMWH is a form of heparin that has been broken down into smaller molecules. It has a longer half-life than standard heparin and can be given once or twice daily by subcutaneous injection.
3. Direct oral anticoagulants (DOACs): These are newer oral anticoagulants that work by directly inhibiting specific clotting factors in the coagulation cascade. Examples include apixaban, rivaroxaban, and dabigatran.
4. Vitamin K antagonists: These are older oral anticoagulants that work by inhibiting the action of vitamin K, which is necessary for the formation of clotting factors. Warfarin is an example of a vitamin K antagonist.

Anticoagulants are used to prevent and treat a variety of conditions, including deep vein thrombosis (DVT), pulmonary embolism (PE), atrial fibrillation, and prosthetic heart valve thrombosis. It is important to note that anticoagulants can increase the risk of bleeding, so they must be used with caution and regular monitoring of blood clotting times may be required.

Aortic valve stenosis is a cardiac condition characterized by the narrowing or stiffening of the aortic valve, which separates the left ventricle (the heart's main pumping chamber) from the aorta (the large artery that carries oxygen-rich blood to the rest of the body). This narrowing or stiffening prevents the aortic valve from opening fully, resulting in reduced blood flow from the left ventricle to the aorta and the rest of the body.

The narrowing can be caused by several factors, including congenital heart defects, calcification (hardening) of the aortic valve due to aging, or scarring of the valve due to rheumatic fever or other inflammatory conditions. As a result, the left ventricle must work harder to pump blood through the narrowed valve, which can lead to thickening and enlargement of the left ventricular muscle (left ventricular hypertrophy).

Symptoms of aortic valve stenosis may include chest pain or tightness, shortness of breath, fatigue, dizziness or fainting, and heart palpitations. Severe aortic valve stenosis can lead to serious complications such as heart failure, arrhythmias, or even sudden cardiac death. Treatment options may include medications to manage symptoms, lifestyle changes, or surgical intervention such as aortic valve replacement.

Prosthesis failure is a term used to describe a situation where a prosthetic device, such as an artificial joint or limb, has stopped functioning or failed to meet its intended purpose. This can be due to various reasons, including mechanical failure, infection, loosening of the device, or a reaction to the materials used in the prosthesis.

Mechanical failure can occur due to wear and tear, manufacturing defects, or improper use of the prosthetic device. Infection can also lead to prosthesis failure, particularly in cases where the prosthesis is implanted inside the body. The immune system may react to the presence of the foreign material, leading to inflammation and infection.

Loosening of the prosthesis can also cause it to fail over time, as the device becomes less stable and eventually stops working properly. Additionally, some people may have a reaction to the materials used in the prosthesis, leading to tissue damage or other complications that can result in prosthesis failure.

In general, prosthesis failure can lead to decreased mobility, pain, and the need for additional surgeries or treatments to correct the problem. It is important for individuals with prosthetic devices to follow their healthcare provider's instructions carefully to minimize the risk of prosthesis failure and ensure that the device continues to function properly over time.

Aortic valve insufficiency, also known as aortic regurgitation or aortic incompetence, is a cardiac condition in which the aortic valve does not close properly during the contraction phase of the heart cycle. This allows blood to flow back into the left ventricle from the aorta, instead of being pumped out to the rest of the body. As a result, the left ventricle must work harder to maintain adequate cardiac output, which can lead to left ventricular enlargement and heart failure over time if left untreated.

The aortic valve is a trileaflet valve that lies between the left ventricle and the aorta. During systole (the contraction phase of the heart cycle), the aortic valve opens to allow blood to be pumped out of the left ventricle into the aorta and then distributed to the rest of the body. During diastole (the relaxation phase of the heart cycle), the aortic valve closes to prevent blood from flowing back into the left ventricle.

Aortic valve insufficiency can be caused by various conditions, including congenital heart defects, infective endocarditis, rheumatic heart disease, Marfan syndrome, and trauma. Symptoms of aortic valve insufficiency may include shortness of breath, fatigue, chest pain, palpitations, and edema (swelling). Diagnosis is typically made through physical examination, echocardiography, and other imaging studies. Treatment options depend on the severity of the condition and may include medication, surgery to repair or replace the aortic valve, or a combination of both.

In medical terms, the heart is a muscular organ located in the thoracic cavity that functions as a pump to circulate blood throughout the body. It's responsible for delivering oxygen and nutrients to the tissues and removing carbon dioxide and other wastes. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it out to the rest of the body. The heart's rhythmic contractions and relaxations are regulated by a complex electrical conduction system.

Prosthesis implantation is a surgical procedure where an artificial device or component, known as a prosthesis, is placed inside the body to replace a missing or damaged body part. The prosthesis can be made from various materials such as metal, plastic, or ceramic and is designed to perform the same function as the original body part.

The implantation procedure involves making an incision in the skin to create a pocket where the prosthesis will be placed. The prosthesis is then carefully positioned and secured in place using screws, cement, or other fixation methods. In some cases, tissue from the patient's own body may be used to help anchor the prosthesis.

Once the prosthesis is in place, the incision is closed with sutures or staples, and the area is bandaged. The patient will typically need to undergo rehabilitation and physical therapy to learn how to use the new prosthesis and regain mobility and strength.

Prosthesis implantation is commonly performed for a variety of reasons, including joint replacement due to arthritis or injury, dental implants to replace missing teeth, and breast reconstruction after mastectomy. The specific procedure and recovery time will depend on the type and location of the prosthesis being implanted.

Prostheses: Artificial substitutes or replacements for missing body parts, such as limbs, eyes, or teeth. They are designed to restore the function, appearance, or mobility of the lost part. Prosthetic devices can be categorized into several types, including:

1. External prostheses: Devices that are attached to the outside of the body, like artificial arms, legs, hands, and feet. These may be further classified into:
a. Cosmetic or aesthetic prostheses: Primarily designed to improve the appearance of the affected area.
b. Functional prostheses: Designed to help restore the functionality and mobility of the lost limb.
2. Internal prostheses: Implanted artificial parts that replace missing internal organs, bones, or tissues, such as heart valves, hip joints, or intraocular lenses.

Implants: Medical devices or substances that are intentionally placed inside the body to replace or support a missing or damaged biological structure, deliver medication, monitor physiological functions, or enhance bodily functions. Examples of implants include:

1. Orthopedic implants: Devices used to replace or reinforce damaged bones, joints, or cartilage, such as knee or hip replacements.
2. Cardiovascular implants: Devices that help support or regulate heart function, like pacemakers, defibrillators, and artificial heart valves.
3. Dental implants: Artificial tooth roots that are placed into the jawbone to support dental prostheses, such as crowns, bridges, or dentures.
4. Neurological implants: Devices used to stimulate nerves, brain structures, or spinal cord tissues to treat various neurological conditions, like deep brain stimulators for Parkinson's disease or cochlear implants for hearing loss.
5. Ophthalmic implants: Artificial lenses that are placed inside the eye to replace a damaged or removed natural lens, such as intraocular lenses used in cataract surgery.

The tricuspid valve is the heart valve that separates the right atrium and the right ventricle in the human heart. It is called "tricuspid" because it has three leaflets or cusps, which are also referred to as flaps or segments. These cusps are named anterior, posterior, and septal. The tricuspid valve's function is to prevent the backflow of blood from the ventricle into the atrium during systole, ensuring unidirectional flow of blood through the heart.

A joint prosthesis, also known as an artificial joint or a replacement joint, is a surgical implant used to replace all or part of a damaged or diseased joint. The most common types of joint prostheses are total hip replacements and total knee replacements. These prostheses typically consist of a combination of metal, plastic, and ceramic components that are designed to replicate the movement and function of a natural joint.

Joint prostheses are usually recommended for patients who have severe joint pain or mobility issues that cannot be adequately managed with other treatments such as physical therapy, medication, or lifestyle changes. The goal of joint replacement surgery is to relieve pain, improve joint function, and enhance the patient's quality of life.

Joint prostheses are typically made from materials such as titanium, cobalt-chrome alloys, stainless steel, polyethylene plastic, and ceramics. The choice of material depends on a variety of factors, including the patient's age, activity level, weight, and overall health.

While joint replacement surgery is generally safe and effective, there are risks associated with any surgical procedure, including infection, blood clots, implant loosening or failure, and nerve damage. Patients who undergo joint replacement surgery typically require several weeks of rehabilitation and physical therapy to regain strength and mobility in the affected joint.

Mitral valve insufficiency, also known as mitral regurgitation, is a cardiac condition in which the mitral valve located between the left atrium and left ventricle of the heart does not close properly, causing blood to flow backward into the atrium during contraction of the ventricle. This leads to an increased volume load on the left heart chamber and can result in symptoms such as shortness of breath, fatigue, and fluid retention. The condition can be caused by various factors including valve damage due to degenerative changes, infective endocarditis, rheumatic heart disease, or trauma. Treatment options include medication, mitral valve repair, or replacement surgery depending on the severity and underlying cause of the insufficiency.

The pulmonary valve, also known as the pulmonic valve, is a semilunar valve located at the exit of the right ventricle of the heart and the beginning of the pulmonary artery. It has three cusps or leaflets that prevent the backflow of blood from the pulmonary artery into the right ventricle during ventricular diastole, ensuring unidirectional flow of blood towards the lungs for oxygenation.

Bacterial endocarditis is a medical condition characterized by the inflammation and infection of the inner layer of the heart, known as the endocardium. This infection typically occurs when bacteria enter the bloodstream and attach themselves to damaged or abnormal heart valves or other parts of the endocardium. The bacteria can then multiply and cause the formation of vegetations, which are clusters of infected tissue that can further damage the heart valves and lead to serious complications such as heart failure, stroke, or even death if left untreated.

Bacterial endocarditis is a relatively uncommon but potentially life-threatening condition that requires prompt medical attention. Risk factors for developing bacterial endocarditis include pre-existing heart conditions such as congenital heart defects, artificial heart valves, previous history of endocarditis, or other conditions that damage the heart valves. Intravenous drug use is also a significant risk factor for this condition.

Symptoms of bacterial endocarditis may include fever, chills, fatigue, muscle and joint pain, shortness of breath, chest pain, and a new or changing heart murmur. Diagnosis typically involves a combination of medical history, physical examination, blood cultures, and imaging tests such as echocardiography. Treatment usually involves several weeks of intravenous antibiotics to eradicate the infection, and in some cases, surgical intervention may be necessary to repair or replace damaged heart valves.

A knee prosthesis, also known as a knee replacement or artificial knee joint, is a medical device used to replace the damaged or diseased weight-bearing surfaces of the knee joint. It typically consists of three components: the femoral component (made of metal) that fits over the end of the thighbone (femur), the tibial component (often made of metal and plastic) that fits into the top of the shinbone (tibia), and a patellar component (usually made of plastic) that replaces the damaged surface of the kneecap.

The primary goal of knee prosthesis is to relieve pain, restore function, and improve quality of life for individuals with advanced knee joint damage due to conditions such as osteoarthritis, rheumatoid arthritis, or traumatic injuries. The procedure to implant a knee prosthesis is called knee replacement surgery or total knee arthroplasty (TKA).

A hip prosthesis, also known as a total hip replacement, is a surgical implant designed to replace the damaged or diseased components of the human hip joint. The procedure involves replacing the femoral head (the ball at the top of the thigh bone) and the acetabulum (the socket in the pelvis) with artificial parts, typically made from materials such as metal, ceramic, or plastic.

The goal of a hip prosthesis is to relieve pain, improve joint mobility, and restore function, allowing patients to return to their normal activities and enjoy an improved quality of life. The procedure is most commonly performed in individuals with advanced osteoarthritis, rheumatoid arthritis, or other degenerative conditions that have caused significant damage to the hip joint.

There are several different types of hip prostheses available, each with its own unique design and set of benefits and risks. The choice of prosthesis will depend on a variety of factors, including the patient's age, activity level, overall health, and specific medical needs. In general, however, all hip prostheses are designed to provide a durable, long-lasting solution for patients suffering from debilitating joint pain and stiffness.

Phonocardiography is a non-invasive medical procedure that involves the graphical representation and analysis of sounds produced by the heart. It uses a device called a phonocardiograph to record these sounds, which are then displayed as waveforms on a screen. The procedure is often used in conjunction with other diagnostic techniques, such as electrocardiography (ECG), to help diagnose various heart conditions, including valvular heart disease and heart murmurs.

During the procedure, a specialized microphone called a phonendoscope is placed on the chest wall over the area of the heart. The microphone picks up the sounds generated by the heart's movements, such as the closing and opening of the heart valves, and transmits them to the phonocardiograph. The phonocardiograph then converts these sounds into a visual representation, which can be analyzed for any abnormalities or irregularities in the heart's function.

Phonocardiography is a valuable tool for healthcare professionals, as it can provide important insights into the health and functioning of the heart. By analyzing the waveforms produced during phonocardiography, doctors can identify any potential issues with the heart's valves or other structures, which may require further investigation or treatment. Overall, phonocardiography is an essential component of modern cardiac diagnostics, helping to ensure that patients receive accurate and timely diagnoses for their heart conditions.

Mitral valve stenosis is a cardiac condition characterized by the narrowing or stiffening of the mitral valve, one of the four heart valves that regulate blood flow through the heart. This narrowing prevents the mitral valve from fully opening during diastole (relaxation phase of the heart cycle), leading to restricted flow of oxygenated blood from the left atrium into the left ventricle.

The narrowing or stiffening of the mitral valve can be caused by various factors, such as rheumatic heart disease, congenital heart defects, aging, or calcium deposits on the valve leaflets. As a result, the left atrium has to work harder to pump blood into the left ventricle, causing increased pressure in the left atrium and pulmonary veins. This can lead to symptoms such as shortness of breath, fatigue, coughing, and heart palpitations.

Mitral valve stenosis is typically diagnosed through a combination of medical history, physical examination, and imaging techniques like echocardiography or cardiac catheterization. Treatment options may include medications to manage symptoms and prevent complications, as well as surgical interventions such as mitral valve repair or replacement to alleviate the stenosis and improve heart function.

Cardiac catheterization is a medical procedure used to diagnose and treat cardiovascular conditions. In this procedure, a thin, flexible tube called a catheter is inserted into a blood vessel in the arm or leg and threaded up to the heart. The catheter can be used to perform various diagnostic tests, such as measuring the pressure inside the heart chambers and assessing the function of the heart valves.

Cardiac catheterization can also be used to treat certain cardiovascular conditions, such as narrowed or blocked arteries. In these cases, a balloon or stent may be inserted through the catheter to open up the blood vessel and improve blood flow. This procedure is known as angioplasty or percutaneous coronary intervention (PCI).

Cardiac catheterization is typically performed in a hospital cardiac catheterization laboratory by a team of healthcare professionals, including cardiologists, radiologists, and nurses. The procedure may be done under local anesthesia with sedation or general anesthesia, depending on the individual patient's needs and preferences.

Overall, cardiac catheterization is a valuable tool in the diagnosis and treatment of various heart conditions, and it can help improve symptoms, reduce complications, and prolong life for many patients.

A reoperation is a surgical procedure that is performed again on a patient who has already undergone a previous operation for the same or related condition. Reoperations may be required due to various reasons, such as inadequate initial treatment, disease recurrence, infection, or complications from the first surgery. The nature and complexity of a reoperation can vary widely depending on the specific circumstances, but it often carries higher risks and potential complications compared to the original operation.

The International Normalized Ratio (INR) is a standardized measurement of the prothrombin time (PT), which is the time it takes for blood to clot. The INR is used to monitor and regulate the effects of anticoagulant medications, such as warfarin, that affect the blood's ability to clot.

The INR is calculated by dividing the patient's PT by a control value (the PT of normal, healthy blood), raised to the power of a sensitivity factor called the International Sensitivity Index (ISI). The ISI is specific to the thromboplastin reagent used in the PT assay.

The INR provides a consistent and comparable way to monitor anticoagulation therapy across different laboratories, regardless of the thromboplastin reagent used. This helps ensure that patients receive appropriate doses of anticoagulant medications and reduces the risk of bleeding or clotting complications.

In general, an INR range of 2.0 to 3.0 is recommended for most people taking anticoagulants for conditions such as atrial fibrillation, deep vein thrombosis, or pulmonary embolism. However, the target INR range may vary depending on individual patient factors and medical indications.

Treatment outcome is a term used to describe the result or effect of medical treatment on a patient's health status. It can be measured in various ways, such as through symptoms improvement, disease remission, reduced disability, improved quality of life, or survival rates. The treatment outcome helps healthcare providers evaluate the effectiveness of a particular treatment plan and make informed decisions about future care. It is also used in clinical research to compare the efficacy of different treatments and improve patient care.

Transesophageal echocardiography (TEE) is a type of echocardiogram, which is a medical test that uses sound waves to create detailed images of the heart. In TEE, a special probe containing a transducer is passed down the esophagus (the tube that connects the mouth to the stomach) to obtain views of the heart from behind. This allows for more detailed images of the heart structures and function compared to a standard echocardiogram, which uses a probe placed on the chest. TEE is often used in patients with poor image quality from a standard echocardiogram or when more detailed images are needed to diagnose or monitor certain heart conditions. It is typically performed by a trained cardiologist or sonographer under the direction of a cardiologist.

Postoperative complications refer to any unfavorable condition or event that occurs during the recovery period after a surgical procedure. These complications can vary in severity and may include, but are not limited to:

1. Infection: This can occur at the site of the incision or inside the body, such as pneumonia or urinary tract infection.
2. Bleeding: Excessive bleeding (hemorrhage) can lead to a drop in blood pressure and may require further surgical intervention.
3. Blood clots: These can form in the deep veins of the legs (deep vein thrombosis) and can potentially travel to the lungs (pulmonary embolism).
4. Wound dehiscence: This is when the surgical wound opens up, which can lead to infection and further complications.
5. Pulmonary issues: These include atelectasis (collapsed lung), pneumonia, or respiratory failure.
6. Cardiovascular problems: These include abnormal heart rhythms (arrhythmias), heart attack, or stroke.
7. Renal failure: This can occur due to various reasons such as dehydration, blood loss, or the use of certain medications.
8. Pain management issues: Inadequate pain control can lead to increased stress, anxiety, and decreased mobility.
9. Nausea and vomiting: These can be caused by anesthesia, opioid pain medication, or other factors.
10. Delirium: This is a state of confusion and disorientation that can occur in the elderly or those with certain medical conditions.

Prompt identification and management of these complications are crucial to ensure the best possible outcome for the patient.

Cardiovascular complications in pregnancy refer to conditions that affect the heart and blood vessels, which can arise during pregnancy, childbirth, or after delivery. These complications can be pre-existing or new-onset and can range from mild to severe, potentially threatening the life of both the mother and the fetus. Some examples of cardiovascular complications in pregnancy include:

1. Hypertension disorders: This includes chronic hypertension (high blood pressure before pregnancy), gestational hypertension (high blood pressure that develops after 20 weeks of pregnancy), and preeclampsia/eclampsia (a pregnancy-specific disorder characterized by high blood pressure, proteinuria, and potential organ damage).

2. Cardiomyopathy: A condition in which the heart muscle becomes weakened, leading to an enlarged heart and reduced pumping efficiency. Peripartum cardiomyopathy is a specific type that occurs during pregnancy or in the months following delivery.

3. Arrhythmias: Irregularities in the heart's rhythm, such as tachycardia (rapid heartbeat) or bradycardia (slow heartbeat), can occur during pregnancy and may require medical intervention.

4. Valvular heart disease: Pre-existing valve disorders, like mitral stenosis or aortic insufficiency, can worsen during pregnancy due to increased blood volume and cardiac output. Additionally, new valve issues might develop during pregnancy.

5. Venous thromboembolism (VTE): Pregnancy increases the risk of developing blood clots in the veins, particularly deep vein thrombosis (DVT) or pulmonary embolism (PE).

6. Ischemic heart disease: Although rare, coronary artery disease and acute coronary syndrome can occur during pregnancy, especially in women with risk factors such as obesity, diabetes, or smoking history.

7. Heart failure: Severe cardiac dysfunction leading to fluid accumulation, shortness of breath, and reduced exercise tolerance may develop due to any of the above conditions or other underlying heart diseases.

Early recognition, monitoring, and appropriate management of these cardiovascular complications in pregnancy are crucial for maternal and fetal well-being.

"Device Removal" in a medical context generally refers to the surgical or nonsurgical removal of a medical device that has been previously implanted in a patient's body. The purpose of removing the device may vary, depending on the individual case. Some common reasons for device removal include infection, malfunction, rejection, or when the device is no longer needed.

Examples of medical devices that may require removal include pacemakers, implantable cardioverter-defibrillators (ICDs), artificial joints, orthopedic hardware, breast implants, cochlear implants, and intrauterine devices (IUDs). The procedure for device removal will depend on the type of device, its location in the body, and the reason for its removal.

It is important to note that device removal carries certain risks, such as bleeding, infection, damage to surrounding tissues, or complications related to anesthesia. Therefore, the decision to remove a medical device should be made carefully, considering both the potential benefits and risks of the procedure.

Paroxysmal dyspnea is a medical term used to describe sudden and recurring episodes of difficulty breathing or shortness of breath. It can occur in people with various underlying medical conditions such as heart disease, lung disease, or neuromuscular disorders. The severity and duration of the symptoms may vary from person to person, but they usually last for a few minutes to a few hours.

Paroxysmal dyspnea is different from chronic dyspnea, which is persistent and continuous shortness of breath that may worsen over time. Paroxysmal dyspnea can be a medical emergency, especially if it is accompanied by chest pain, palpitations, or other symptoms. It is essential to seek immediate medical attention if you experience sudden and severe shortness of breath.

Heart rate is the number of heartbeats per unit of time, often expressed as beats per minute (bpm). It can vary significantly depending on factors such as age, physical fitness, emotions, and overall health status. A resting heart rate between 60-100 bpm is generally considered normal for adults, but athletes and individuals with high levels of physical fitness may have a resting heart rate below 60 bpm due to their enhanced cardiovascular efficiency. Monitoring heart rate can provide valuable insights into an individual's health status, exercise intensity, and response to various treatments or interventions.

A visual prosthesis, also known as a retinal implant or bionic eye, is a medical device that aims to restore some functional vision in individuals who have severe visual impairment or blindness due to certain eye conditions such as retinitis pigmentosa or age-related macular degeneration.

The prosthesis works by electrically stimulating the remaining viable nerve cells in the retina, which then transmit the signals to the brain via the optic nerve. The device typically consists of a camera that captures visual information, a processor that converts the images into electrical signals, and an electrode array that is implanted onto the surface of the retina.

The electrical stimulation of the retinal cells creates patterns of light in the individual's visual field, allowing them to perceive shapes, edges, and movements. While the level of visual acuity achieved with current visual prostheses is still limited, they can significantly improve the quality of life for some individuals by enabling them to perform tasks such as recognizing objects, navigating their environment, and identifying facial expressions.

Thrombosis is the formation of a blood clot (thrombus) inside a blood vessel, obstructing the flow of blood through the circulatory system. When a clot forms in an artery, it can cut off the supply of oxygen and nutrients to the tissues served by that artery, leading to damage or tissue death. If a thrombus forms in the heart, it can cause a heart attack. If a thrombus breaks off and travels through the bloodstream, it can lodge in a smaller vessel, causing blockage and potentially leading to damage in the organ that the vessel supplies. This is known as an embolism.

Thrombosis can occur due to various factors such as injury to the blood vessel wall, abnormalities in blood flow, or changes in the composition of the blood. Certain medical conditions, medications, and lifestyle factors can increase the risk of thrombosis. Treatment typically involves anticoagulant or thrombolytic therapy to dissolve or prevent further growth of the clot, as well as addressing any underlying causes.

Follow-up studies are a type of longitudinal research that involve repeated observations or measurements of the same variables over a period of time, in order to understand their long-term effects or outcomes. In medical context, follow-up studies are often used to evaluate the safety and efficacy of medical treatments, interventions, or procedures.

In a typical follow-up study, a group of individuals (called a cohort) who have received a particular treatment or intervention are identified and then followed over time through periodic assessments or data collection. The data collected may include information on clinical outcomes, adverse events, changes in symptoms or functional status, and other relevant measures.

The results of follow-up studies can provide important insights into the long-term benefits and risks of medical interventions, as well as help to identify factors that may influence treatment effectiveness or patient outcomes. However, it is important to note that follow-up studies can be subject to various biases and limitations, such as loss to follow-up, recall bias, and changes in clinical practice over time, which must be carefully considered when interpreting the results.

Artificial limbs, also known as prosthetics, are artificial substitutes that replace a part or all of an absent extremity or limb. They are designed to restore the function, mobility, and appearance of the lost limb as much as possible. Artificial limbs can be made from various materials such as wood, plastic, metal, or carbon fiber, and they can be custom-made to fit the individual's specific needs and measurements.

Prosthetic limbs can be categorized into two main types: cosmetic and functional. Cosmetic prosthetics are designed to look like natural limbs and are primarily used to improve the appearance of the person. Functional prosthetics, on the other hand, are designed to help the individual perform specific tasks and activities. They may include features such as hooks, hands, or specialized feet that can be used for different purposes.

Advances in technology have led to the development of more sophisticated artificial limbs, including those that can be controlled by the user's nervous system, known as bionic prosthetics. These advanced prosthetic devices can provide a greater degree of mobility and control for the user, allowing them to perform complex movements and tasks with ease.

Warfarin is a anticoagulant medication that works by inhibiting the vitamin K-dependent activation of several coagulation factors (factors II, VII, IX, and X). This results in prolonged clotting times and reduced thrombus formation. It is commonly used to prevent and treat blood clots in conditions such as atrial fibrillation, deep vein thrombosis, and pulmonary embolism. Warfarin is also known by its brand names Coumadin and Jantoven.

It's important to note that warfarin has a narrow therapeutic index, meaning that the difference between an effective dose and a toxic one is small. Therefore, it requires careful monitoring of the patient's coagulation status through regular blood tests (INR) to ensure that the dosage is appropriate and to minimize the risk of bleeding complications.

Echocardiography is a medical procedure that uses sound waves to produce detailed images of the heart's structure, function, and motion. It is a non-invasive test that can help diagnose various heart conditions, such as valve problems, heart muscle damage, blood clots, and congenital heart defects.

During an echocardiogram, a transducer (a device that sends and receives sound waves) is placed on the chest or passed through the esophagus to obtain images of the heart. The sound waves produced by the transducer bounce off the heart structures and return to the transducer, which then converts them into electrical signals that are processed to create images of the heart.

There are several types of echocardiograms, including:

* Transthoracic echocardiography (TTE): This is the most common type of echocardiogram and involves placing the transducer on the chest.
* Transesophageal echocardiography (TEE): This type of echocardiogram involves passing a specialized transducer through the esophagus to obtain images of the heart from a closer proximity.
* Stress echocardiography: This type of echocardiogram is performed during exercise or medication-induced stress to assess how the heart functions under stress.
* Doppler echocardiography: This type of echocardiogram uses sound waves to measure blood flow and velocity in the heart and blood vessels.

Echocardiography is a valuable tool for diagnosing and managing various heart conditions, as it provides detailed information about the structure and function of the heart. It is generally safe, non-invasive, and painless, making it a popular choice for doctors and patients alike.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Prosthesis fitting is the process of selecting, designing, fabricating, and fitting a prosthetic device to replace a part of an individual's body that is missing due to congenital absence, illness, injury, or amputation. The primary goal of prosthesis fitting is to restore the person's physical function, mobility, and independence, as well as improve their overall quality of life.

The process typically involves several steps:

1. Assessment: A thorough evaluation of the patient's medical history, physical condition, and functional needs is conducted to determine the most appropriate type of prosthesis. This may include measurements, castings, or digital scans of the residual limb.

2. Design: Based on the assessment, a customized design plan is created for the prosthetic device, taking into account factors such as the patient's lifestyle, occupation, and personal preferences.

3. Fabrication: The prosthesis is manufactured using various materials, components, and techniques to meet the specific requirements of the patient. This may involve the use of 3D printing, computer-aided design (CAD), or traditional handcrafting methods.

4. Fitting: Once the prosthesis is fabricated, it is carefully fitted to the patient's residual limb, ensuring optimal comfort, alignment, and stability. Adjustments may be made as needed to achieve the best fit and function.

5. Training: The patient receives training on how to use and care for their new prosthetic device, including exercises to strengthen the residual limb and improve overall mobility. Follow-up appointments are scheduled to monitor progress, make any necessary adjustments, and provide ongoing support.

Doppler echocardiography is a type of ultrasound test that uses high-frequency sound waves to produce detailed images of the heart and its blood vessels. It measures the direction and speed of blood flow in the heart and major blood vessels leading to and from the heart. This helps to evaluate various conditions such as valve problems, congenital heart defects, and heart muscle diseases.

In Doppler echocardiography, a small handheld device called a transducer is placed on the chest, which emits sound waves that bounce off the heart and blood vessels. The transducer then picks up the returning echoes, which are processed by a computer to create moving images of the heart.

The Doppler effect is used to measure the speed and direction of blood flow. This occurs when the frequency of the sound waves changes as they bounce off moving objects, such as red blood cells. By analyzing these changes, the ultrasound machine can calculate the velocity and direction of blood flow in different parts of the heart.

Doppler echocardiography is a non-invasive test that does not require any needles or dyes. It is generally safe and painless, although patients may experience some discomfort from the pressure applied by the transducer on the chest. The test usually takes about 30 to 60 minutes to complete.

Endocarditis is an inflammation of the inner layer of the heart chambers and heart valves, called the endocardium. This inflammation typically results from a bacterial or, less commonly, fungal infection that travels through the bloodstream and attaches to damaged areas of the heart.

There are two main types of endocarditis:

1. Acute Endocarditis: Develops quickly and can be severe, causing fever, chills, shortness of breath, fatigue, and heart murmurs. It may lead to serious complications like heart failure, embolism (blood clots that travel to other parts of the body), and damage to heart valves.

2. Subacute Endocarditis: Develops more slowly, often causing milder symptoms that can be mistaken for a cold or flu. Symptoms may include fatigue, weakness, fever, night sweats, weight loss, joint pain, and heart murmurs. Subacute endocarditis is more likely to affect people with previously damaged heart valves or congenital heart conditions.

Treatment usually involves several weeks of intravenous antibiotics or antifungal medications, depending on the cause of the infection. In some cases, surgery may be required to repair or replace damaged heart valves. Preventive measures include good oral hygiene and prompt treatment of infections, especially in individuals at a higher risk for endocarditis, such as those with congenital heart defects, artificial heart valves, or previous history of endocarditis.

A neural prosthesis is a type of medical device that is designed to assist or replace the function of impaired nervous system structures. These devices can be used to stimulate nerves and restore sensation, movement, or other functions that have been lost due to injury or disease. They may also be used to monitor neural activity and provide feedback to the user or to a external device.

Neural prostheses can take many forms, depending on the specific function they are intended to restore. For example, a cochlear implant is a type of neural prosthesis that is used to restore hearing in people with severe to profound hearing loss. The device consists of a microphone, a processor, and a array of electrodes that are implanted in the inner ear. Sound is converted into electrical signals by the microphone and processor, and these signals are then used to stimulate the remaining nerve cells in the inner ear, allowing the user to hear sounds.

Other examples of neural prostheses include deep brain stimulation devices, which are used to treat movement disorders such as Parkinson's disease; retinal implants, which are used to restore vision in people with certain types of blindness; and sacral nerve stimulators, which are used to treat urinary incontinence.

It is important to note that neural prostheses are not intended to cure or fully reverse the underlying condition that caused the impairment, but rather to help restore some level of function and improve the user's quality of life.

Mitral valve prolapse (MVP) is a heart condition where the mitral valve, which separates the left atrium and left ventricle in the heart, doesn't function properly. In MVP, one or both of the mitral valve flaps (known as leaflets) bulge or billow into the left atrium during the contraction of the left ventricle. This prolapse can cause a leakage of blood back into the atrium, known as mitral regurgitation. In many cases, MVP is asymptomatic and doesn't require treatment, but in some instances, it may lead to complications such as infective endocarditis or arrhythmias. The exact causes of MVP are not fully understood, but it can be associated with certain genetic factors, connective tissue disorders, and mitral valve abnormalities present at birth.

An ossicular prosthesis is a medical device used to replace one or more of the small bones (ossicles) in the middle ear that are involved in hearing. These bones, known as the malleus, incus, and stapes, form a chain responsible for transmitting sound vibrations from the eardrum to the inner ear.

An ossicular prosthesis is typically made of biocompatible materials such as ceramic, plastic, or metal. The prosthesis is designed to bypass damaged or missing ossicles and reestablish the connection between the eardrum and the inner ear, thereby improving hearing function. Ossicular prostheses are often used in surgeries aimed at reconstructing the middle ear, such as tympanoplasty or stapedectomy, to treat various types of conductive hearing loss.

Heart failure is a pathophysiological state in which the heart is unable to pump sufficient blood to meet the metabolic demands of the body or do so only at the expense of elevated filling pressures. It can be caused by various cardiac disorders, including coronary artery disease, hypertension, valvular heart disease, cardiomyopathy, and arrhythmias. Symptoms may include shortness of breath, fatigue, and fluid retention. Heart failure is often classified based on the ejection fraction (EF), which is the percentage of blood that is pumped out of the left ventricle during each contraction. A reduced EF (less than 40%) is indicative of heart failure with reduced ejection fraction (HFrEF), while a preserved EF (greater than or equal to 50%) is indicative of heart failure with preserved ejection fraction (HFpEF). There is also a category of heart failure with mid-range ejection fraction (HFmrEF) for those with an EF between 40-49%.

A dental prosthesis is a device that replaces one or more missing teeth or parts of teeth to correct deficiencies in chewing ability, speech, and aesthetics. It can be removable or fixed (permanent) and can be made from various materials such as acrylic resin, porcelain, metal alloys, or a combination of these. Examples of dental prostheses include dentures, bridges, crowns, and implants.

Blood vessel prosthesis implantation is a surgical procedure in which an artificial blood vessel, also known as a vascular graft or prosthetic graft, is inserted into the body to replace a damaged or diseased native blood vessel. The prosthetic graft can be made from various materials such as Dacron (polyester), PTFE (polytetrafluoroethylene), or bovine/human tissue.

The implantation of a blood vessel prosthesis is typically performed to treat conditions that cause narrowing or blockage of the blood vessels, such as atherosclerosis, aneurysms, or traumatic injuries. The procedure may be used to bypass blocked arteries in the legs (peripheral artery disease), heart (coronary artery bypass surgery), or neck (carotid endarterectomy). It can also be used to replace damaged veins for hemodialysis access in patients with kidney failure.

The success of blood vessel prosthesis implantation depends on various factors, including the patient's overall health, the location and extent of the vascular disease, and the type of graft material used. Possible complications include infection, bleeding, graft thrombosis (clotting), and graft failure, which may require further surgical intervention or endovascular treatments.

Venous valves are one-way flaps made of thin, flexible tissue that lie inside your veins. They allow blood to flow towards the heart but prevent it from flowing backward. These valves are especially important in the veins of the legs, where they help to counteract the force of gravity and ensure that blood flows back up to the heart. When venous valves become damaged or weakened, blood can pool in the veins, leading to conditions such as varicose veins or chronic venous insufficiency.

Prosthesis-related infections, also known as prosthetic joint infections (PJIs), are infections that occur around or within a prosthetic device, such as an artificial joint. These infections can be caused by bacteria, fungi, or other microorganisms and can lead to serious complications if not treated promptly and effectively.

Prosthesis-related infections can occur soon after the implantation of the prosthetic device (early infection) or months or even years later (late infection). Early infections are often caused by bacteria that enter the surgical site during the procedure, while late infections may be caused by hematogenous seeding (i.e., when bacteria from another source spread through the bloodstream and settle in the prosthetic device) or by contamination during a subsequent medical procedure.

Symptoms of prosthesis-related infections can include pain, swelling, redness, warmth, and drainage around the affected area. In some cases, patients may also experience fever, chills, or fatigue. Diagnosis typically involves a combination of clinical evaluation, laboratory tests (such as blood cultures, joint fluid analysis, and tissue biopsy), and imaging studies (such as X-rays, CT scans, or MRI).

Treatment of prosthesis-related infections usually involves a combination of antibiotics and surgical intervention. The specific treatment approach will depend on the type and severity of the infection, as well as the patient's overall health status. In some cases, it may be necessary to remove or replace the affected prosthetic device.

Tricuspid valve insufficiency, also known as tricuspid regurgitation, is a cardiac condition in which the tricuspid valve located between the right atrium and right ventricle of the heart does not close properly, allowing blood to flow back into the right atrium during contraction of the right ventricle. This results in a portion of the blood being pumped inefficiently, which can lead to volume overload of the right side of the heart and potentially result in symptoms such as fatigue, weakness, shortness of breath, and fluid retention. The condition can be congenital or acquired, with common causes including dilated cardiomyopathy, infective endocarditis, rheumatic heart disease, and trauma.

Heart disease is a broad term for a class of diseases that involve the heart or blood vessels. It's often used to refer to conditions that include:

1. Coronary artery disease (CAD): This is the most common type of heart disease. It occurs when the arteries that supply blood to the heart become hardened and narrowed due to the buildup of cholesterol and other substances, which can lead to chest pain (angina), shortness of breath, or a heart attack.

2. Heart failure: This condition occurs when the heart is unable to pump blood efficiently to meet the body's needs. It can be caused by various conditions, including coronary artery disease, high blood pressure, and cardiomyopathy.

3. Arrhythmias: These are abnormal heart rhythms, which can be too fast, too slow, or irregular. They can lead to symptoms such as palpitations, dizziness, and fainting.

4. Valvular heart disease: This involves damage to one or more of the heart's four valves, which control blood flow through the heart. Damage can be caused by various conditions, including infection, rheumatic fever, and aging.

5. Cardiomyopathy: This is a disease of the heart muscle that makes it harder for the heart to pump blood efficiently. It can be caused by various factors, including genetics, viral infections, and drug abuse.

6. Pericardial disease: This involves inflammation or other problems with the sac surrounding the heart (pericardium). It can cause chest pain and other symptoms.

7. Congenital heart defects: These are heart conditions that are present at birth, such as a hole in the heart or abnormal blood vessels. They can range from mild to severe and may require medical intervention.

8. Heart infections: The heart can become infected by bacteria, viruses, or parasites, leading to various symptoms and complications.

It's important to note that many factors can contribute to the development of heart disease, including genetics, lifestyle choices, and certain medical conditions. Regular check-ups and a healthy lifestyle can help reduce the risk of developing heart disease.

Congenital heart defects (CHDs) are structural abnormalities in the heart that are present at birth. They can affect any part of the heart's structure, including the walls of the heart, the valves inside the heart, and the major blood vessels that lead to and from the heart.

Congenital heart defects can range from mild to severe and can cause various symptoms depending on the type and severity of the defect. Some common symptoms of CHDs include cyanosis (a bluish tint to the skin, lips, and fingernails), shortness of breath, fatigue, poor feeding, and slow growth in infants and children.

There are many different types of congenital heart defects, including:

1. Septal defects: These are holes in the walls that separate the four chambers of the heart. The two most common septal defects are atrial septal defect (ASD) and ventricular septal defect (VSD).
2. Valve abnormalities: These include narrowed or leaky valves, which can affect blood flow through the heart.
3. Obstruction defects: These occur when blood flow is blocked or restricted due to narrowing or absence of a part of the heart's structure. Examples include pulmonary stenosis and coarctation of the aorta.
4. Cyanotic heart defects: These cause a lack of oxygen in the blood, leading to cyanosis. Examples include tetralogy of Fallot and transposition of the great arteries.

The causes of congenital heart defects are not fully understood, but genetic factors and environmental influences during pregnancy may play a role. Some CHDs can be detected before birth through prenatal testing, while others may not be diagnosed until after birth or later in childhood. Treatment for CHDs may include medication, surgery, or other interventions to improve blood flow and oxygenation of the body's tissues.

A blood vessel prosthesis is a medical device that is used as a substitute for a damaged or diseased natural blood vessel. It is typically made of synthetic materials such as polyester, Dacron, or ePTFE (expanded polytetrafluoroethylene) and is designed to mimic the function of a native blood vessel by allowing the flow of blood through it.

Blood vessel prostheses are used in various surgical procedures, including coronary artery bypass grafting, peripheral arterial reconstruction, and the creation of arteriovenous fistulas for dialysis access. The choice of material and size of the prosthesis depends on several factors, such as the location and diameter of the vessel being replaced, the patient's age and overall health status, and the surgeon's preference.

It is important to note that while blood vessel prostheses can be effective in restoring blood flow, they may also carry risks such as infection, thrombosis (blood clot formation), and graft failure over time. Therefore, careful patient selection, surgical technique, and postoperative management are crucial for the success of these procedures.

Tissue engineering is a branch of biomedical engineering that combines the principles of engineering, materials science, and biological sciences to develop functional substitutes for damaged or diseased tissues and organs. It involves the creation of living, three-dimensional structures that can restore, maintain, or improve tissue function. This is typically accomplished through the use of cells, scaffolds (biodegradable matrices), and biologically active molecules. The goal of tissue engineering is to develop biological substitutes that can ultimately restore normal function and structure in damaged tissues or organs.

A dental prosthesis that is supported by dental implants is an artificial replacement for one or more missing teeth. It is a type of dental restoration that is anchored to the jawbone using one or more titanium implant posts, which are surgically placed into the bone. The prosthesis is then attached to the implants, providing a stable and secure fit that closely mimics the function and appearance of natural teeth.

There are several types of implant-supported dental prostheses, including crowns, bridges, and dentures. A single crown may be used to replace a single missing tooth, while a bridge or denture can be used to replace multiple missing teeth. The specific type of prosthesis used will depend on the number and location of the missing teeth, as well as the patient's individual needs and preferences.

Implant-supported dental prostheses offer several advantages over traditional removable dentures, including improved stability, comfort, and functionality. They also help to preserve jawbone density and prevent facial sagging that can occur when teeth are missing. However, they do require a surgical procedure to place the implants, and may not be suitable for all patients due to factors such as bone density or overall health status.

Delayed embryo implantation is a medical condition that occurs when the fertilized egg (embryo) does not attach to the uterine lining (endometrium) within the expected time frame, typically within 7-10 days after ovulation. In delayed implantation, the embryo may take longer than usual to implant, which can result in a prolonged menstrual cycle or irregular bleeding.

There are several possible reasons for delayed implantation, including hormonal imbalances, uterine abnormalities, immune system dysfunction, and chromosomal abnormalities in the embryo. In some cases, delayed implantation may be a sign of infertility or recurrent pregnancy loss.

Diagnosis of delayed implantation typically involves monitoring hormone levels and tracking menstrual cycles. Imaging tests such as ultrasound or hysteroscopy may also be used to assess the uterine lining and detect any abnormalities that could be contributing to the delay in implantation.

Treatment for delayed implantation depends on the underlying cause. Hormonal therapies, medications to suppress the immune system, or surgery to correct uterine abnormalities may be recommended in some cases. In vitro fertilization (IVF) with embryo transfer may also be considered as a treatment option for couples experiencing delayed implantation and infertility.

Calcinosis is a medical condition characterized by the abnormal deposit of calcium salts in various tissues of the body, commonly under the skin or in the muscles and tendons. These calcium deposits can form hard lumps or nodules that can cause pain, inflammation, and restricted mobility. Calcinosis can occur as a complication of other medical conditions, such as autoimmune disorders, kidney disease, and hypercalcemia (high levels of calcium in the blood). In some cases, the cause of calcinosis may be unknown. Treatment for calcinosis depends on the underlying cause and may include medications to manage calcium levels, physical therapy, and surgical removal of large deposits.

Cochlear implantation is a surgical procedure in which a device called a cochlear implant is inserted into the inner ear (cochlea) of a person with severe to profound hearing loss. The implant consists of an external component, which includes a microphone, processor, and transmitter, and an internal component, which includes a receiver and electrode array.

The microphone picks up sounds from the environment and sends them to the processor, which analyzes and converts the sounds into electrical signals. These signals are then transmitted to the receiver, which stimulates the electrode array in the cochlea. The electrodes directly stimulate the auditory nerve fibers, bypassing the damaged hair cells in the inner ear that are responsible for normal hearing.

The brain interprets these electrical signals as sound, allowing the person to perceive and understand speech and other sounds. Cochlear implantation is typically recommended for people who do not benefit from traditional hearing aids and can significantly improve communication, quality of life, and social integration for those with severe to profound hearing loss.

An amputee is a person who has had a limb or extremity removed by trauma, medical illness, or surgical intervention. Amputation may affect any part of the body, including fingers, toes, hands, feet, arms, and legs. The level of amputation can vary from partial loss to complete removal of the affected limb.

There are several reasons why a person might become an amputee:
- Trauma: Accidents, injuries, or violence can result in amputations due to severe tissue damage or irreparable vascular injury.
- Medical illness: Certain medical conditions such as diabetes, peripheral arterial disease, and cancer may require amputation if the affected limb cannot be saved through other treatments.
- Infection: Severe infections that do not respond to antibiotics or other treatments may necessitate amputation to prevent the spread of infection.
- Congenital defects: Some individuals are born with missing or malformed limbs, making them congenital amputees.

Amputees face various challenges, including physical limitations, emotional distress, and social adjustment. However, advancements in prosthetics and rehabilitation have significantly improved the quality of life for many amputees, enabling them to lead active and fulfilling lives.

An artificial larynx, also known as a voice prosthesis or speech aid, is a device used to help individuals who have undergone a laryngectomy (surgical removal of the larynx) or have other conditions that prevent them from speaking normally. The device generates sound mechanically, which can then be shaped into speech by the user.

There are two main types of artificial larynx devices:

1. External: This type of device consists of a small electronic unit that produces sound when the user presses a button or activates it with a breath. The sound is then directed through a tube or hose into a face mask or a mouthpiece, where the user can shape it into speech.
2. Internal: An internal artificial larynx, also known as a voice prosthesis, is implanted in the body during surgery. It works by allowing air to flow from the trachea into the esophagus and then through the voice prosthesis, which creates sound that can be used for speech.

Both types of artificial larynx devices require practice and training to use effectively, but they can significantly improve communication and quality of life for individuals who have lost their natural voice due to laryngeal cancer or other conditions.

Arthroplasty, replacement, is a surgical procedure where a damaged or diseased joint surface is removed and replaced with an artificial implant or device. The goal of this surgery is to relieve pain, restore function, and improve the quality of life for patients who have severe joint damage due to arthritis or other conditions.

During the procedure, the surgeon removes the damaged cartilage and bone from the joint and replaces them with a metal, plastic, or ceramic component that replicates the shape and function of the natural joint surface. The most common types of joint replacement surgery are hip replacement, knee replacement, and shoulder replacement.

The success rate of joint replacement surgery is generally high, with many patients experiencing significant pain relief and improved mobility. However, as with any surgical procedure, there are risks involved, including infection, blood clots, implant loosening or failure, and nerve damage. Therefore, it's essential to discuss the potential benefits and risks of joint replacement surgery with a healthcare provider before making a decision.

Absorbable implants are medical devices that are designed to be placed inside the body during a surgical procedure, where they provide support, stabilization, or other functions, and then gradually break down and are absorbed by the body over time. These implants are typically made from materials such as polymers, proteins, or ceramics that have been engineered to degrade at a controlled rate, allowing them to be resorbed and eliminated from the body without the need for a second surgical procedure to remove them.

Absorbable implants are often used in orthopedic, dental, and plastic surgery applications, where they can help promote healing and support tissue regeneration. For example, absorbable screws or pins may be used to stabilize fractured bones during the healing process, after which they will gradually dissolve and be absorbed by the body. Similarly, absorbable membranes may be used in dental surgery to help guide the growth of new bone and gum tissue around an implant, and then be resorbed over time.

It's important to note that while absorbable implants offer several advantages over non-absorbable materials, such as reduced risk of infection and improved patient comfort, they may also have some limitations. For example, the mechanical properties of absorbable materials may not be as strong as those of non-absorbable materials, which could affect their performance in certain applications. Additionally, the degradation products of absorbable implants may cause local inflammation or other adverse reactions in some patients. As with any medical device, the use of absorbable implants should be carefully considered and discussed with a qualified healthcare professional.

A maxillofacial prosthesis is a custom-made device used to replace all or part of a facial feature, such as an eye, ear, nose, or lip, that has been lost due to trauma, cancer surgery, or other causes. It is typically made from materials like silicone, acrylic, or nylon and is designed to mimic the appearance and texture of natural skin and tissues.

Maxillofacial prostheses are created by trained professionals called maxillofacial prosthodontists, who have specialized training in the diagnosis, treatment planning, and rehabilitation of patients with facial defects. The process of creating a maxillofacial prosthesis typically involves taking an impression of the affected area, creating a custom-made mold, and then fabricating the prosthesis to fit precisely over the defect.

Maxillofacial prostheses can help improve patients' appearance, self-confidence, and quality of life by restoring their facial symmetry and functionality. They may also help protect the underlying tissues and structures from injury or infection, and can be used in conjunction with other treatments, such as radiation therapy or chemotherapy, to enhance their effectiveness.

An artificial eye, also known as a prosthetic eye, is a type of medical device that is used to replace a natural eye that has been removed or is not functional due to injury, disease, or congenital abnormalities. It is typically made of acrylic or glass and is custom-made to match the size, shape, and color of the patient's other eye as closely as possible.

The artificial eye is designed to fit over the eye socket and rest on the eyelids, allowing the person to have a more natural appearance and improve their ability to blink and close their eye. It does not restore vision, but it can help protect the eye socket and improve the patient's self-esteem and quality of life.

The process of fitting an artificial eye typically involves several appointments with an ocularist, who is a healthcare professional trained in the measurement, design, and fabrication of prosthetic eyes. The ocularist will take impressions of the eye socket, create a model, and then use that model to make the artificial eye. Once the artificial eye is made, the ocularist will fit it and make any necessary adjustments to ensure that it is comfortable and looks natural.

Heparin is defined as a highly sulfated glycosaminoglycan (a type of polysaccharide) that is widely present in many tissues, but is most commonly derived from the mucosal tissues of mammalian lungs or intestinal mucosa. It is an anticoagulant that acts as an inhibitor of several enzymes involved in the blood coagulation cascade, primarily by activating antithrombin III which then neutralizes thrombin and other clotting factors.

Heparin is used medically to prevent and treat thromboembolic disorders such as deep vein thrombosis, pulmonary embolism, and certain types of heart attacks. It can also be used during hemodialysis, cardiac bypass surgery, and other medical procedures to prevent the formation of blood clots.

It's important to note that while heparin is a powerful anticoagulant, it does not have any fibrinolytic activity, meaning it cannot dissolve existing blood clots. Instead, it prevents new clots from forming and stops existing clots from growing larger.

Retrospective studies, also known as retrospective research or looking back studies, are a type of observational study that examines data from the past to draw conclusions about possible causal relationships between risk factors and outcomes. In these studies, researchers analyze existing records, medical charts, or previously collected data to test a hypothesis or answer a specific research question.

Retrospective studies can be useful for generating hypotheses and identifying trends, but they have limitations compared to prospective studies, which follow participants forward in time from exposure to outcome. Retrospective studies are subject to biases such as recall bias, selection bias, and information bias, which can affect the validity of the results. Therefore, retrospective studies should be interpreted with caution and used primarily to generate hypotheses for further testing in prospective studies.

Heart transplantation is a surgical procedure where a diseased, damaged, or failing heart is removed and replaced with a healthy donor heart. This procedure is usually considered as a last resort for patients with end-stage heart failure or severe coronary artery disease who have not responded to other treatments. The donor heart typically comes from a brain-dead individual whose family has agreed to donate their loved one's organs for transplantation. Heart transplantation is a complex and highly specialized procedure that requires a multidisciplinary team of healthcare professionals, including cardiologists, cardiac surgeons, anesthesiologists, perfusionists, nurses, and other support staff. The success rates for heart transplantation have improved significantly over the past few decades, with many patients experiencing improved quality of life and increased survival rates. However, recipients of heart transplants require lifelong immunosuppressive therapy to prevent rejection of the donor heart, which can increase the risk of infections and other complications.

Prospective studies, also known as longitudinal studies, are a type of cohort study in which data is collected forward in time, following a group of individuals who share a common characteristic or exposure over a period of time. The researchers clearly define the study population and exposure of interest at the beginning of the study and follow up with the participants to determine the outcomes that develop over time. This type of study design allows for the investigation of causal relationships between exposures and outcomes, as well as the identification of risk factors and the estimation of disease incidence rates. Prospective studies are particularly useful in epidemiology and medical research when studying diseases with long latency periods or rare outcomes.

No FAQ available that match "heart valve prosthesis implantation"

No images available that match "heart valve prosthesis implantation"