Coagulation of blood in any of the CORONARY VESSELS. The presence of a blood clot (THROMBUS) often leads to MYOCARDIAL INFARCTION.
Sinus Thrombosis, Intracranial
Formation or presence of a blood clot (THROMBUS) in the CRANIAL SINUSES, large endothelium-lined venous channels situated within the SKULL. Intracranial sinuses, also called cranial venous sinuses, include the superior sagittal, cavernous, lateral, petrous sinuses, and many others. Cranial sinus thrombosis can lead to severe HEADACHE; SEIZURE; and other neurological defects.
Formation or presence of a blood clot (THROMBUS) in a blood vessel within the SKULL. Intracranial thrombosis can lead to thrombotic occlusions and BRAIN INFARCTION. The majority of the thrombotic occlusions are associated with ATHEROSCLEROSIS.
Carotid Artery Thrombosis
Blood clot formation in any part of the CAROTID ARTERIES. This may produce CAROTID STENOSIS or occlusion of the vessel, leading to TRANSIENT ISCHEMIC ATTACK; CEREBRAL INFARCTION; or AMAUROSIS FUGAX.
Sagittal Sinus Thrombosis
Formation or presence of a blood clot (THROMBUS) in the SUPERIOR SAGITTAL SINUS or the inferior sagittal sinus. Sagittal sinus thrombosis can result from infections, hematological disorders, CRANIOCEREBRAL TRAUMA; and NEUROSURGICAL PROCEDURES. Clinical features are primarily related to the increased intracranial pressure causing HEADACHE; NAUSEA; and VOMITING. Severe cases can evolve to SEIZURES or COMA.
Intracranial Embolism and Thrombosis
A vein on either side of the body which is formed by the union of the external and internal iliac veins and passes upward to join with its fellow of the opposite side to form the inferior vena cava.
A disorder of HEMOSTASIS in which there is a tendency for the occurrence of THROMBOSIS.
The vein accompanying the femoral artery in the same sheath; it is a continuation of the popliteal vein and becomes the external iliac vein.
Upper Extremity Deep Vein Thrombosis
DEEP VEIN THROMBOSIS of an upper extremity vein (e.g., AXILLARY VEIN; SUBCLAVIAN VEIN; and JUGULAR VEINS). It is associated with mechanical factors (Upper Extremity Deep Vein Thrombosis, Primary) secondary to other anatomic factors (Upper Extremity Deep Vein Thrombosis, Secondary). Symptoms may include sudden onset of pain, warmth, redness, blueness, and swelling in the arm.
A short thick vein formed by union of the superior mesenteric vein and the splenic vein.
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.
Heat- and storage-labile plasma glycoprotein which accelerates the conversion of prothrombin to thrombin in blood coagulation. Factor V accomplishes this by forming a complex with factor Xa, phospholipid, and calcium (prothrombinase complex). Deficiency of factor V leads to Owren's disease.
The process which spontaneously arrests the flow of BLOOD from vessels carrying blood under pressure. It is accomplished by contraction of the vessels, adhesion and aggregation of formed blood elements (eg. ERYTHROCYTE AGGREGATION), and the process of BLOOD COAGULATION.
Heparin fractions with a molecular weight usually between 4000 and 6000 kD. These low-molecular-weight fractions are effective antithrombotic agents. Their administration reduces the risk of hemorrhage, they have a longer half-life, and their platelet interactions are reduced in comparison to unfractionated heparin. They also provide an effective prophylaxis against postoperative major pulmonary embolism.
Cavernous Sinus Thrombosis
Formation or presence of a blood clot (THROMBUS) in the CAVERNOUS SINUS of the brain. Infections of the paranasal sinuses and adjacent structures, CRANIOCEREBRAL TRAUMA, and THROMBOPHILIA are associated conditions. Clinical manifestations include dysfunction of cranial nerves III, IV, V, and VI, marked periorbital swelling, chemosis, fever, and visual loss. (From Adams et al., Principles of Neurology, 6th ed, p711)
The process of the interaction of BLOOD COAGULATION FACTORS that results in an insoluble FIBRIN clot.
The presence of antibodies directed against phospholipids (ANTIBODIES, ANTIPHOSPHOLIPID). The condition is associated with a variety of diseases, notably systemic lupus erythematosus and other connective tissue diseases, thrombopenia, and arterial or venous thromboses. In pregnancy it can cause abortion. Of the phospholipids, the cardiolipins show markedly elevated levels of anticardiolipin antibodies (ANTIBODIES, ANTICARDIOLIPIN). Present also are high levels of lupus anticoagulant (LUPUS COAGULATION INHIBITOR).
Vena Cava, Inferior
Platelet Aggregation Inhibitors
Drugs or agents which antagonize or impair any mechanism leading to blood platelet aggregation, whether during the phases of activation and shape change or following the dense-granule release reaction and stimulation of the prostaglandin-thromboxane system.
Lateral Sinus Thrombosis
Formation or presence of a blood clot (THROMBUS) in the LATERAL SINUSES. This condition is often associated with ear infections (OTITIS MEDIA or MASTOIDITIS) without antibiotic treatment. In developed nations, lateral sinus thrombosis can result from CRANIOCEREBRAL TRAUMA; BRAIN NEOPLASMS; NEUROSURGICAL PROCEDURES; THROMBOPHILIA; and other conditions. Clinical features include HEADACHE; VERTIGO; and increased intracranial pressure.
Fibrin Fibrinogen Degradation Products
Soluble protein fragments formed by the proteolytic action of plasmin on fibrin or fibrinogen. FDP and their complexes profoundly impair the hemostatic process and are a major cause of hemorrhage in intravascular coagulation and fibrinolysis.
Protein S Deficiency
An autosomal dominant disorder showing decreased levels of plasma protein S antigen or activity, associated with venous thrombosis and pulmonary embolism. PROTEIN S is a vitamin K-dependent plasma protein that inhibits blood clotting by serving as a cofactor for activated PROTEIN C (also a vitamin K-dependent protein), and the clinical manifestations of its deficiency are virtually identical to those of protein C deficiency. Treatment with heparin for acute thrombotic processes is usually followed by maintenance administration of coumarin drugs for the prevention of recurrent thrombosis. (From Harrison's Principles of Internal Medicine, 12th ed, p1511; Wintrobe's Clinical Hematology, 9th ed, p1523)
The attachment of PLATELETS to one another. This clumping together can be induced by a number of agents (e.g., THROMBIN; COLLAGEN) and is part of the mechanism leading to the formation of a THROMBUS.
Veins which return blood from the intestines; the inferior mesenteric vein empties into the splenic vein, the superior mesenteric vein joins the splenic vein to form the portal vein.
The continuation of the axillary vein which follows the subclavian artery and then joins the internal jugular vein to form the brachiocephalic vein.
A plasma protein that is the inactive precursor of thrombin. It is converted to thrombin by a prothrombin activator complex consisting of factor Xa, factor V, phospholipid, and calcium ions. Deficiency of prothrombin leads to hypoprothrombinemia.
The vein formed by the union of the anterior and posterior tibial veins; it courses through the popliteal space and becomes the femoral vein.
Veins in the neck which drain the brain, face, and neck into the brachiocephalic or subclavian veins.
Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.
Obstruction of a vein or VEINS (embolism) by a blood clot (THROMBUS) in the blood stream.
Autoantibodies directed against phospholipids. These antibodies are characteristically found in patients with systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC;), ANTIPHOSPHOLIPID SYNDROME; related autoimmune diseases, some non-autoimmune diseases, and also in healthy individuals.
Protein C Deficiency
An absence or deficiency in PROTEIN C which leads to impaired regulation of blood coagulation. It is associated with an increased risk of severe or premature thrombosis. (Stedman's Med. Dict., 26th ed.)
Large endothelium-lined venous channels situated between the two layers of DURA MATER, the endosteal and the meningeal layers. They are devoid of valves and are parts of the venous system of dura mater. Major cranial sinuses include a postero-superior group (such as superior sagittal, inferior sagittal, straight, transverse, and occipital) and an antero-inferior group (such as cavernous, petrosal, and basilar plexus).
Activated Protein C Resistance
Lupus Coagulation Inhibitor
An antiphospholipid antibody found in association with systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC;), ANTIPHOSPHOLIPID SYNDROME; and in a variety of other diseases as well as in healthy individuals. In vitro, the antibody interferes with the conversion of prothrombin to thrombin and prolongs the partial thromboplastin time. In vivo, it exerts a procoagulant effect resulting in thrombosis mainly in the larger veins and arteries. It further causes obstetrical complications, including fetal death and spontaneous abortion, as well as a variety of hematologic and neurologic complications.
Constituent composed of protein and phospholipid that is widely distributed in many tissues. It serves as a cofactor with factor VIIa to activate factor X in the extrinsic pathway of blood coagulation.
Use of infusions of FIBRINOLYTIC AGENTS to destroy or dissolve thrombi in blood vessels or bypass grafts.
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.
Short thick veins which return blood from the kidneys to the vena cava.
Vein formed by the union (at the hilus of the spleen) of several small veins from the stomach, pancreas, spleen and mesentery.
Ultrasonography, Doppler, Duplex
A condition in which the hepatic venous outflow is obstructed anywhere from the small HEPATIC VEINS to the junction of the INFERIOR VENA CAVA and the RIGHT ATRIUM. Usually the blockage is extrahepatic and caused by blood clots (THROMBUS) or fibrous webs. Parenchymal FIBROSIS is uncommon.
Antithrombin III Deficiency
An absence or reduced level of Antithrombin III leading to an increased risk for thrombosis.
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 natural enzymatic dissolution of FIBRIN.
The venous trunk of the upper limb; a continuation of the basilar and brachial veins running from the lower border of the teres major muscle to the outer border of the first rib where it becomes the subclavian vein.
Mesenteric Vascular Occlusion
Obstruction of the flow in the SPLANCHNIC CIRCULATION by ATHEROSCLEROSIS; EMBOLISM; THROMBOSIS; STENOSIS; TRAUMA; and compression or intrinsic pressure from adjacent tumors. Rare causes are drugs, intestinal parasites, and vascular immunoinflammatory diseases such as PERIARTERITIS NODOSA and THROMBOANGIITIS OBLITERANS. (From Juergens et al., Peripheral Vascular Diseases, 5th ed, pp295-6)
A vitamin-K dependent zymogen present in the blood, which, upon activation by thrombin and thrombomodulin exerts anticoagulant properties by inactivating factors Va and VIIIa at the rate-limiting steps of thrombin formation.
The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. (From Martindale, The Extra Pharmacopoeia, 30th ed, p5)
Catheterization, Central Venous
A protein derived from FIBRINOGEN in the presence of THROMBIN, which forms part of the blood clot.
Vena Cava Filters
Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.
A condition characterized by a chronically swollen limb, often a leg with stasis dermatitis and ulcerations. This syndrome can appear soon after phlebitis or years later. Postphlebitic syndrome is the result of damaged or incompetent venous valves in the limbs. Distended, tortuous VARICOSE VEINS are usually present. Leg pain may occur after long period of standing.
Endogenous factors and drugs that directly inhibit the action of THROMBIN, usually by blocking its enzymatic activity. They are distinguished from INDIRECT THROMBIN INHIBITORS, such as HEPARIN, which act by enhancing the inhibitory effects of antithrombins.
Arteriovenous Shunt, Surgical
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.
An effective inhibitor of platelet aggregation commonly used in the placement of STENTS in CORONARY ARTERIES.
Partial Thromboplastin Time
The time required for the appearance of FIBRIN strands following the mixing of PLASMA with phospholipid platelet substitute (e.g., crude cephalins, soybean phosphatides). It is a test of the intrinsic pathway (factors VIII, IX, XI, and XII) and the common pathway (fibrinogen, prothrombin, factors V and X) of BLOOD COAGULATION. It is used as a screening test and to monitor HEPARIN therapy.
Tomography, X-Ray Computed
Angioplasty, Balloon, Coronary
Dilation of an occluded coronary artery (or arteries) by means of a balloon catheter to restore myocardial blood supply.
A macrolide compound obtained from Streptomyces hygroscopicus that acts by selectively blocking the transcriptional activation of cytokines thereby inhibiting cytokine production. It is bioactive only when bound to IMMUNOPHILINS. Sirolimus is a potent immunosuppressant and possesses both antifungal and antineoplastic properties.
Antiphospholipid antibodies found in association with systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC;), ANTIPHOSPHOLIPID SYNDROME; and in a variety of other diseases as well as in healthy individuals. The antibodies are detected by solid-phase IMMUNOASSAY employing the purified phospholipid antigen CARDIOLIPIN.
Blood Coagulation Factors
Endogenous substances, usually proteins, that are involved in the blood coagulation process.
Blood Coagulation Disorders
Hemorrhagic and thrombotic disorders that occur as a consequence of abnormalities in blood coagulation due to a variety of factors such as COAGULATION PROTEIN DISORDERS; BLOOD PLATELET DISORDERS; BLOOD PROTEIN DISORDERS or nutritional conditions.
A subnormal level of BLOOD PLATELETS.
Superior Sagittal Sinus
The long large endothelium-lined venous channel on the top outer surface of the brain. It receives blood from a vein in the nasal cavity, runs backwards, and gradually increases in size as blood drains from veins of the brain and the DURA MATER. Near the lower back of the CRANIUM, the superior sagittal sinus deviates to one side (usually the right) and continues on as one of the TRANSVERSE SINUSES.
The vitamin K-dependent cofactor of activated PROTEIN C. Together with protein C, it inhibits the action of factors VIIIa and Va. A deficiency in protein S; (PROTEIN S DEFICIENCY); can lead to recurrent venous and arterial thrombosis.
beta 2-Glycoprotein I
A 44-kDa highly glycosylated plasma protein that binds phospholipids including CARDIOLIPIN; APOLIPOPROTEIN E RECEPTOR; membrane phospholipids, and other anionic phospholipid-containing moieties. It plays a role in coagulation and apoptotic processes. Formerly known as apolipoprotein H, it is an autoantigen in patients with ANTIPHOSPHOLIPID ANTIBODIES.
Tissue Plasminogen Activator
A proteolytic enzyme in the serine protease family found in many tissues which converts PLASMINOGEN to FIBRINOLYSIN. It has fibrin-binding activity and is immunologically different from UROKINASE-TYPE PLASMINOGEN ACTIVATOR. The primary sequence, composed of 527 amino acids, is identical in both the naturally occurring and synthetic proteases.
Arterial Occlusive Diseases
Pathological processes which result in the partial or complete obstruction of ARTERIES. They are characterized by greatly reduced or absence of blood flow through these vessels. They are also known as arterial insufficiency.
Intermittent Pneumatic Compression Devices
Instruments that generate intermittent forces, uniformed or graduated, to facilitate the emptying of VEINS. These devices are used to reduce limb EDEMA and prevent venous THROMBOEMBOLISM, such as deep vein thrombosis in the legs.
Blood Vessel Prosthesis
Disseminated Intravascular Coagulation
An enzyme formed from PROTHROMBIN that converts FIBRINOGEN to FIBRIN.
Disease Models, Animal
Pregnancy Complications, Cardiovascular
Rare chronic inflammatory disease involving the small blood vessels. It is of unknown etiology and characterized by mucocutaneous ulceration in the mouth and genital region and uveitis with hypopyon. The neuro-ocular form may cause blindness and death. SYNOVITIS; THROMBOPHLEBITIS; gastrointestinal ulcerations; RETINAL VASCULITIS; and OPTIC ATROPHY may occur as well.
von Willebrand Factor
A high-molecular-weight plasma protein, produced by endothelial cells and megakaryocytes, that is part of the factor VIII/von Willebrand factor complex. The von Willebrand factor has receptors for collagen, platelets, and ristocetin activity as well as the immunologically distinct antigenic determinants. It functions in adhesion of platelets to collagen and hemostatic plug formation. The prolonged bleeding time in VON WILLEBRAND DISEASES is due to the deficiency of this factor.
Ultrasonography, Doppler, Color
Ultrasonography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image. This type of ultrasonography is well-suited to identifying the location of high-velocity flow (such as in a stenosis) or of mapping the extent of flow in a certain region.
A myeloproliferative disorder of unknown etiology, characterized by abnormal proliferation of all hematopoietic bone marrow elements and an absolute increase in red cell mass and total blood volume, associated frequently with splenomegaly, leukocytosis, and thrombocythemia. Hematopoiesis is also reactive in extramedullary sites (liver and spleen). In time myelofibrosis occurs.
Clotting time of PLASMA recalcified in the presence of excess TISSUE THROMBOPLASTIN. Factors measured are FIBRINOGEN; PROTHROMBIN; FACTOR V; FACTOR VII; and FACTOR X. It is used for monitoring anticoagulant therapy with COUMARINS.
Ultrasonography applying the Doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. (Stedman, 25th ed)
Pregnancy Complications, Hematologic
A cell surface glycoprotein of endothelial cells that binds thrombin and serves as a cofactor in the activation of protein C and its regulation of blood coagulation.
Platelet Glycoprotein GPIIb-IIIa Complex
Platelet membrane glycoprotein complex important for platelet adhesion and aggregation. It is an integrin complex containing INTEGRIN ALPHAIIB and INTEGRIN BETA3 which recognizes the arginine-glycine-aspartic acid (RGD) sequence present on several adhesive proteins. As such, it is a receptor for FIBRINOGEN; VON WILLEBRAND FACTOR; FIBRONECTIN; VITRONECTIN; and THROMBOSPONDINS. A deficiency of GPIIb-IIIa results in GLANZMANN THROMBASTHENIA.
Blood Coagulation Disorders, Inherited
Hemorrhagic and thrombotic disorders that occur as a consequence of inherited abnormalities in blood coagulation.
Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.
A coumarin that is used as an anticoagulant. Its actions and uses are similar to those of WARFARIN. (From Martindale, The Extra Pharmacopoeia, 30th ed, p233)
Factor V Deficiency
A deficiency of blood coagulation factor V (known as proaccelerin or accelerator globulin or labile factor) leading to a rare hemorrhagic tendency known as Owren's disease or parahemophilia. It varies greatly in severity. Factor V deficiency is an autosomal recessive trait. (Dorland, 27th ed)
Homopolymer of tetrafluoroethylene. Nonflammable, tough, inert plastic tubing or sheeting; used to line vessels, insulate, protect or lubricate apparatus; also as filter, coating for surgical implants or as prosthetic material. Synonyms: Fluoroflex; Fluoroplast; Ftoroplast; Halon; Polyfene; PTFE; Tetron.
Coronary Artery Disease
Pathological processes of CORONARY ARTERIES that may derive from a congenital abnormality, atherosclerotic, or non-atherosclerotic cause.
Coated Materials, Biocompatible
Plasminogen Activator Inhibitor 1
A member of the serpin family of proteins. It inhibits both the tissue-type and urokinase-type plasminogen activators.
Clotting time of PLASMA mixed with a THROMBIN solution. It is a measure of the conversion of FIBRINOGEN to FIBRIN, which is prolonged by AFIBRINOGENEMIA, abnormal fibrinogen, or the presence of inhibitory substances, e.g., fibrin-fibrinogen degradation products, or HEPARIN. BATROXOBIN, a thrombin-like enzyme unaffected by the presence of heparin, may be used in place of thrombin.
Blood Vessel Prosthesis Implantation
A repeat operation for the same condition in the same patient due to disease progression or recurrence, or as followup to failed previous surgery.
Urokinase-Type Plasminogen Activator
Enlarged and tortuous VEINS.
Platelet Factor 4
A CXC chemokine that is found in the alpha granules of PLATELETS. The protein has a molecular size of 7800 kDa and can occur as a monomer, a dimer or a tetramer depending upon its concentration in solution. Platelet factor 4 has a high affinity for HEPARIN and is often found complexed with GLYCOPROTEINS such as PROTEIN C.
Activated form of factor X that participates in both the intrinsic and extrinsic pathways of blood coagulation. It catalyzes the conversion of prothrombin to thrombin in conjunction with other cofactors.
Receptors, Purinergic P2Y12
A subclass of purinergic P2Y receptors that have a preference for ADP binding and are coupled to GTP-BINDING PROTEIN ALPHA SUBUNIT, GI. The P2Y12 purinergic receptors are found in PLATELETS where they play an important role regulating PLATELET ACTIVATION.
Embolism and Thrombosis
Single-chain polypeptides of about 65 amino acids (7 kDa) from LEECHES that have a neutral hydrophobic N terminus, an acidic hydrophilic C terminus, and a compact, hydrophobic core region. Recombinant hirudins lack tyr-63 sulfation and are referred to as 'desulfato-hirudins'. They form a stable non-covalent complex with ALPHA-THROMBIN, thereby abolishing its ability to cleave FIBRINOGEN.
Magnetic Resonance Angiography
Non-invasive method of vascular imaging and determination of internal anatomy without injection of contrast media or radiation exposure. The technique is used especially in CEREBRAL ANGIOGRAPHY as well as for studies of other vascular structures.
Either of the two principal arteries on both sides of the neck that supply blood to the head and neck; each divides into two branches, the internal carotid artery and the external carotid artery.
Portasystemic Shunt, Surgical
Surgical venous shunt between the portal and systemic circulation to effect decompression of the portal circulation. It is performed primarily in the treatment of bleeding esophageal varices resulting from portal hypertension. Types of shunt include portacaval, splenorenal, mesocaval, splenocaval, left gastric-caval (coronary-caval), portarenal, umbilicorenal, and umbilicocaval.
Heart Valve Prosthesis
Impaired venous blood flow or venous return (venous stasis), usually caused by inadequate venous valves. Venous insufficiency often occurs in the legs, and is associated with EDEMA and sometimes with VENOUS STASIS ULCERS at the ankle.
Percutaneous Coronary Intervention
A family of percutaneous techniques that are used to manage CORONARY OCCLUSION, including standard balloon angioplasty (PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY), the placement of intracoronary STENTS, and atheroablative technologies (e.g., ATHERECTOMY; ENDARTERECTOMY; THROMBECTOMY; PERCUTANEOUS TRANSLUMINAL LASER ANGIOPLASTY). PTCA was the dominant form of PCI, before the widespread use of stenting.
Blood Coagulation Factor Inhibitors
Substances, usually endogenous, that act as inhibitors of blood coagulation. They may affect one or multiple enzymes throughout the process. As a group, they also inhibit enzymes involved in processes other than blood coagulation, such as those from the complement system, fibrinolytic enzyme system, blood cells, and bacteria.
Platelet Function Tests
Magnetic Resonance Imaging
International Normalized Ratio
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.
Use of a balloon catheter for dilation of an occluded artery. It is used in treatment of arterial occlusive diseases, including renal artery stenosis and arterial occlusions in the leg. For the specific technique of BALLOON DILATION in coronary arteries, ANGIOPLASTY, BALLOON, CORONARY is available.
Streptococcal fibrinolysin . An enzyme produced by hemolytic streptococci. It hydrolyzes amide linkages and serves as an activator of plasminogen. It is used in thrombolytic therapy and is used also in mixtures with streptodornase (STREPTODORNASE AND STREPTOKINASE). EC 3.4.-.
Abnormal increase of resistance to blood flow within the hepatic PORTAL SYSTEM, frequently seen in LIVER CIRRHOSIS and conditions with obstruction of the PORTAL VEIN.
Predictive Value of Tests
In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.
Factor XII Deficiency
An absence or reduced level of blood coagulation factor XII. It normally occurs in the absence of patient or family history of hemorrhagic disorders and is marked by prolonged clotting time.
A nonparametric method of compiling LIFE TABLES or survival tables. It combines calculated probabilities of survival and estimates to allow for observations occurring beyond a measurement threshold, which are assumed to occur randomly. Time intervals are defined as ending each time an event occurs and are therefore unequal. (From Last, A Dictionary of Epidemiology, 1995)
Use of HIRUDINS as an anticoagulant in the treatment of cardiological and hematological disorders.
Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.