TachycardiaTreating atrial fibrillationSinoatrial nodeArrhythmiasJunctionalType of atrial fibrillationOffered to atrial fibrillationAblation of the atrioventricularPacemakerCatheter ablationImpulsesTachycardiasCalled atrial flutterSeptal defectsEpisodesPersistentCardioversionSupraventricularCardiacPeople with atrialDepolarizationFibrillation ablationRight atrialComplicationsAtriumVentricular chambersPatientsMitralAtrio-ventricular nodeVentriclesAfibNodalDofetilideRefractorinessCongenitalChambersElectricalSyndromeConduction systemSymptomsTreatmentHeartbeatBeats per mi
Tachycardia19
- Supraventricular tachycardias include atrial fibrillation, atrial flutter and paroxysmal supraventricular tachycardia. (wikipedia.org)
- Accelerated idioventricular rhythm Monomorphic ventricular tachycardia Polymorphic ventricular tachycardia Ventricular fibrillation Torsades de pointes Arrhythmogenic right ventricular dysplasia Re-entry ventricular arrhythmia These are also known as AV blocks, because the vast majority of them arise from pathology at the atrioventricular node. (wikipedia.org)
- Atrioventricular nodal re-entry tachycardia, which is caused by a dual AV node physiology and AVNRT can only occur in people with it, however almost half of the population have it, though only a few of them will develop AVNRT at some point in life. (wikipedia.org)
- Calcium channel blockers are especially effective in atrial tachycardia with triggered activity as the underlying mechanism. (medscape.com)
- Beta-blockers can reduce the frequency and severity of atrial tachycardia episodes by controlling ventricular response. (medscape.com)
- Many class III antidysrhythmic agents have been shown to be effective in maintaining sinus rhythm after conversion from atrial tachycardia. (medscape.com)
- For patient education information, see the Heart Health Center , as well as Atrial Flutter , Arrhythmias (Heart Rhythm Disorders) , Stroke , Supraventricular Tachycardia (SVT, PSVT) , and Palpitations . (medscape.com)
- OBJECTIVE To assess the efficacy and safety of intravenous dofetilide in preventing induction of atrioventricular re-entrant tachycardia. (bmj.com)
- Fifty one patients with electrically inducible atrioventricular re-entrant tachycardia were allocated to one of five doses of dofetilide (1.5, 3, 6, 9, and 15 μg/kg), two thirds of the dofetilide dose being given over a 15 minute loading period and the remainder over a 45 minute maintenance period. (bmj.com)
- MAIN OUTCOME MEASURE Responders were defined as patients in whom dofetilide prevented reinduction of atrioventricular re-entrant tachycardia at the end of the infusion. (bmj.com)
- In non-responders, dofetilide increased the cycle length of induced atrioventricular re-entrant tachycardia. (bmj.com)
- CONCLUSIONS Dofetilide shows promise as an agent for the prevention of atrioventricular re-entrant tachycardia in patients without structural heart disease. (bmj.com)
- Atrioventricular re-entrant tachycardia is currently treated with various pharmacological agents. (bmj.com)
- 14-16 However, to date there have been no studies on the dose dependent effects of dofetilide on atrioventricular re-entrant tachycardia. (bmj.com)
- Our goal in this study was to assess the efficacy of intravenous dofetilide, in five different dosing regimens, for treating patients with inducible atrioventricular re-entrant tachycardia, by determining its ability to prevent reinduction of the tachycardia. (bmj.com)
- Maintenance of sinus rhythm in patients with supraventricular arrhythmias, including paroxysmal supraventricular tachycardia (PSVT), Wolff-Parkinson-White (WPW) syndrome, junctional ectopic tachycardia, paroxysmal atrial tachycardia, and atrioventricular node re-entrant tachycardia. (pediatriconcall.com)
- F. The most common form of paroxysmal supraventricular tachycardia (PSVT) is AV nodal reentry due to dual pathways of excitation in the region of the AV node (see Figure 1). (rjmatthewsmd.com)
- Ablation of arrhythmias, especially atrial flutter and atrioventricular node reentry tachycardia, is feasible and safe in these patients. (jhpr.ir)
- These include atrial fibrillation, atrial flutter, atrial tachycardia. (medlineplus.gov)
Treating atrial fibrillation1
- There are many different ways of treating atrial fibrillation. (epnet.com)
Sinoatrial node5
- A wave of excitation spreads out from the sinoatrial node through the atria along specialized conduction channels. (wikipedia.org)
- In the heart, normal impulse initiation begins in the sinoatrial node (SAN). (medscape.com)
- Each heartbeat begins with an impulse from the heart's pacemaker (sinus or sinoatrial node). (msdmanuals.com)
- The normal cardiac impulse of the vertebrate heart originates in the pacemaker cells of the sinoatrial node, located in the right atrium. (medscape.com)
- It is called the sinoatrial node, sinus node or SA node. (medlineplus.gov)
Arrhythmias2
- This also protects the ventricles from excessively fast rate response to atrial arrhythmias (see below). (wikipedia.org)
- Atrial fibrillation (AF) is one of the most common arrhythmias. (nature.com)
Junctional2
- Extra beats include premature atrial contractions, premature ventricular contractions and premature junctional contractions. (wikipedia.org)
- After modulation of the atrioventricular node in general, an intrinsic escapement rhythm at the junctional level can remain, the frequency of which is generally between 30 and 50 bpm. (af-ablation.org)
Type of atrial fibrillation4
- In this type of atrial fibrillation, the irregular heart rhythm can't be reset. (mayoclinic.org)
- With this type of atrial fibrillation, your heart rhythm doesn't go back to normal on its own. (seniorhealthcarematters.com)
- This type of atrial fibrillation is continuous and lasts longer than 12 months. (seniorhealthcarematters.com)
- In this type of atrial fibrillation, the abnormal heart rhythm can't be restored. (seniorhealthcarematters.com)
Offered to atrial fibrillation1
- Treatment offered to atrial fibrillation will depend on the root cause, the symptoms being experienced and severity of your condition. (medanta.org)
Ablation of the atrioventricular1
- If pharmacological therapy is insufficient or associated with side effects, the 2006 ACC/AHA/ESC Guidelines recommend ablation of the atrioventricular node (AVN) in conjunction with permanent pacemaker implantation to control heart rate. (ahrq.gov)
Pacemaker5
- Inside your right atrium, the upper chamber is the sinus node, your heart's natural pacemaker. (medanta.org)
- Prior implantation of pacemaker/defibrillator with at least an atrial and RV mid septal lead. (survivornet.com)
- Remote Monitoring of Atrial High Rate Episodes in Pacemaker Patients. (jafib.com)
- The RAPID study is a multicenter, prospective, non-interventional study designed to compare the time from onset to first physician's evaluation of AHRE episode with arrhythmic burden ≥5% (72 minutes) for pacemaker recipients without atrial fibrillation history, between patients followed with RM or conventionally with annual in-hospital visits. (jafib.com)
- The ongoing RAPID study will provide additional information on the role of RM in the management of AHRE detected in pacemaker patients without documented atrial fibrillation history in ordinary clinical practice. (jafib.com)
Catheter ablation2
- There is no consensus on the most efficient catheter ablation (CA) strategy for patients with atrial fibrillation (AF). (biomedcentral.com)
- Radiofrequency catheter ablation techniques are safe and effective as well, especially for patients with poor tolerance to drugs (see figure figure 3b radiofrequency ablation in WPW, as well as in the treatment of atrial flutter and fibrillation by identifying tract carrying the excitation impulse). (rjmatthewsmd.com)
Impulses8
- The atrioventricular node delays impulses by approximately 0.09s. (wikipedia.org)
- In atrial fibrillation, many different electrical impulses happen all at once in your atria, which causes very fast and disorganized electrical activity. (everydayhealth.com)
- The possible causes of atrial fibrillation could be chaotic electrical impulses. (medanta.org)
- The atrioventricular node delays impulses for ~0.1 second before allowing impulses through to the His-Purkinje conduction system, which spreads impulses to the ventricular walls. (wikidoc.org)
- The AV node - the electrical connection between the atria and the ventricles - is bombarded with impulses trying to get through to the ventricles. (seniorhealthcarematters.com)
- Atrial fibrillation and atrial flutter are very fast electrical discharge patterns that make the atria (upper chambers of the heart) contract very rapidly, with some of the electrical impulses reaching the ventricles and sometimes causing them to contract faster and less efficiently than normal. (msdmanuals.com)
- Only some of the chaotic electrical impulses are conducted through the atrioventricular node to the ventricles. (msdmanuals.com)
- For most people who are not being treated for atrial fibrillation, the impulses are conducted to the ventricles at a faster-than-normal rate (often 140 to 160 times per minute, compared to the normal heart rate of about 60 to 100 beats per minute). (msdmanuals.com)
Tachycardias2
- Nowadays, flecainide is recommended as one of the first line therapies for pharmacological conversion as well as maintenance of sinus rhythm in patients with atrial fibrillation and/or supraventricular tachycardias. (wjgnet.com)
- They may pick up very slow heart rates and long pauses, along with episodes of atrial tachycardias. (medlineplus.gov)
Called atrial flutter1
- A person with atrial fibrillation also may have a related heart rhythm problem called atrial flutter. (mayoclinic.org)
Septal defects3
- Objective: To investigate the natural history of secundum atrial septal defects (ASDs) over several years using serial echocardiographic studies. (bmj.com)
- Atrial septal defects (ASDs) constitute the second most common congenital heart lesion in both adult and paediatric populations. (bmj.com)
- 2] Amongst cases of Down syndrome, varying degrees of heart block are seen with atrioventricular septal defects while atrial septal defect is only associated with PR interval prolongation on ECG. (jpgo.org)
Episodes5
- Episodes of atrial fibrillation may come and go, or they may be persistent. (mayoclinic.org)
- Many people with atrial flutter also have episodes of atrial fibrillation. (msdmanuals.com)
- RM can provide early detection of high atrial rate episodes (AHREs) onset and enable prompt medical intervention. (jafib.com)
- Modern cardiac implantable electronic devices (CIEDs) include detailed algorithms and functions for the accurate detection of atrial high rate episodes (AHREs)[ 4 , 5 ]. (jafib.com)
- Secondary objectives include: time to first investigator evaluation of AHRE episodes, regardless of its duration, time to anticoagulant therapy onset, time to any medical reaction related to the treatment of new onset atrial arrhythmia, time to cerebral ischemia, and time to first hospitalization due to cardiovascular issues [ Table 1 ]. (jafib.com)
Persistent3
- Acute conversion of persistent atrial fibrillation during dofetilide loading does not predict long-term atrial fibrillation-free survival. (harvard.edu)
- If you have persistent atrial fibrillation, you'll need treatment such as an electrical shock or medications in order to restore your heart rhythm. (seniorhealthcarematters.com)
- The catheter-based radiofrequency ablation procedure of the atrio-ventricular node is aimed at patients suffering from persistent atrial fibrillation, in which drug therapies for rhythm and heart rate control are not effective. (af-ablation.org)
Cardioversion1
- Atrial flutter in an unstable patient should be treated immediately with synchronized cardioversion. (medscape.com)
Supraventricular1
- Clinical reports have shown that dofetilide is effective in the treatment of supraventricular tachyarrhythmias, such as atrial fibrillation and atrial flutter. (bmj.com)
Cardiac9
- Cardiac atrial fibrillation clinics have a multidisciplinary team that takes referrals and provides teaching for patients with a new or previous diagnosis of Atrial Fibrillation or Atrial Flutter. (vch.ca)
- The cardiac conduction system (and AV node part of it) coordinates myocyte mechanical activity. (wikipedia.org)
- Third-degree atrioventricular (AV) block, also referred to as third-degree heart block or complete heart block (CHB), is an abnormal heart rhythm resulting from a defect in the cardiac conduction system in which there is no conduction through the atrioventricular node (AVN), leading to complete dissociation of the atria and ventricles. (medscape.com)
- Atrial fibrillation is an irregular and rapid heart rate that can increase your risk of stroke, heart failure and other cardiac complications. (medanta.org)
- Congenital complete atrioventricular block may result from a congenital cardiac anomaly or the presence of anti-Ro and/or anti-La antibodies in women who have systemic lupus erythematosus, Sjogren's syndrome, undifferentiated autoimmune disorder, or are asymptomatic. (jpgo.org)
- Down syndrome has a high incidence of congenital cardiac anomalies, however, complete atrioventricular block is rarely seen. (jpgo.org)
- The "ablate-and-pace" approach is the approach of choice in patients with atrial fibrillation, in which a high ventricular response reduces the effectiveness of cardiac resynchronization. (af-ablation.org)
- Congenital anomalies of right atrial components can be associated with clinically significant cardiac malformations. (medscape.com)
- The heart achieves the coordinated contraction of the atrial and ventricular chambers due to the precise timing of the cardiac conduction system (CCS), a specialized complex and heterogeneous network of cells that initiate and allow propagation of action potentials through the heart. (medscape.com)
People with atrial2
- Some people with atrial fibrillation (AFib) don't notice any symptoms. (mayoclinic.org)
- Some people with atrial fibrillation have no symptoms and are unaware of their condition until it's discovered during a physical examination. (seniorhealthcarematters.com)
Depolarization1
- It occurs when the atrial depolarization fails to reach the ventricles or is conducted with an abnormally long delay. (wikipedia.org)
Fibrillation ablation1
- Is atrio-ventricular node ablation a neglected option after failure of atrial fibrillation ablation? (escardio.org)
Right atrial1
- Common findings in these patients were elevated right atrial pressure and diameters and reduced tricuspid annular plane systolic excursion (TAPSE). (jhpr.ir)
Complications1
- Diltiazem is useful for heart rate control in patients with atrial fibrillation -- irregular heartbeat that can lead to heart-related complications -- as it reduces conduction in the atrioventricular node. (yashodahospitals.com)
Atrium6
- The AV node receives two inputs from the right atrium: posteriorly, via the crista terminalis, and anteriorly, via the interatrial septum. (wikipedia.org)
- This condition has traditionally been characterized as a macroreentrant dysrhythmia with the re-entrant loop just above the atrioventricular (AV) node in the right atrium. (medscape.com)
- Within the upper right chamber of your heart (right atrium) is a group of cells called the sinus node. (seniorhealthcarematters.com)
- Through this venous access, a scaler catheter is advanced near the atrium ventricular node (compact part). (af-ablation.org)
- The left atrial appendage is the only trabeculated structure in the left atrium because, unlike the right atrium, the left atrium has no crista terminalis. (medscape.com)
- [ 1 ] The impulse is then conducted through the atrium to the atrioventricular junction from where, after a delay, the electrical signal is propagated to the ventricles along bundles of specialized conduction tissue to the distal Purkinje fibers, which ramify among the contractile myocardium. (medscape.com)
Ventricular chambers1
- Atrioventricular or AV valves are located between the atrial and ventricular chambers on each side, and they prevent backflow into the atria when the ventricles contract. (nurseslabs.com)
Patients11
- The 2011 Focused Update on the Management of Patients with Atrial Fibrillation-by the American College of Cardiology Foundation (ACCF), the AHA, and the Heart Rhythm Society (HRS)-addressed the issue of strict versus lenient rate control in patients with AF. (ahrq.gov)
- reported that miR-328 contributes to the adverse atrial electrical remodeling in dogs and patients with AF 7 . (nature.com)
- One fifth of the patients studied had an insufficient atrial rim by transthoracic echocardiogram to hold an atrial septal occluder. (bmj.com)
- Patients with chronic bifascicular block (BFB) can progress to advanced atrioventricular block (AVB), especially when syncope or a prolonged HV interval is present. (revespcardiol.org)
- These algorithms use long atrioventricular (AV) delays, which may impair AV synchrony and can potentially lead to an increased risk of AV block at higher atrial rates and predispose to mitral regurgitation in certain patients. (acc.org)
- We have created a mathematical network model of the AV node where continuous estimation of the refractory period and conduction delay from 24-hour ambulatory ECGs from patients with permanent AF (n=59) was achieved using a problem-specific genetic algorithm. (lu.se)
- Control of resting ventricular rate in patients with chronic atrial fibrillation in adults. (guidelinecentral.com)
- LANOXIN is indicated for the control of ventricular response rate in adult patients with chronic atrial fibrillation. (guidelinecentral.com)
- Kaplan-Meier survival analysis demonstrated a significant mortality increase in patients with HFrEF (6.1% in HFrEF vs. 1.5% in HFmrEF vs. 1.9% in HFpEF, p = 0.009) that was limited to patients undergoing ablation of the AV node. (uni-luebeck.de)
- In almost 50% of patients with HFrEF AV-node ablation was performed, going along with a significant increase in mortality rate. (uni-luebeck.de)
- Therefore, this procedure is an important therapeutic measure, especially in patients in whom atrial fibrillation appears to be associated with heart failure, and is very effective in controlling relapses and symptoms of heart failure. (af-ablation.org)
Mitral2
- The chronic and recurrent ones are related to underlying structural causes like atrial disease or mitral disease. (rjmatthewsmd.com)
- C. They tend to be recucurrent when an underlying structural cause such as atrial disease or mitral disease is the dominant pathophysiologic factor. (rjmatthewsmd.com)
Atrio-ventricular node2
- What is the ablation procedure for modulating the atrio-ventricular node? (af-ablation.org)
- How is the ablation procedure performed for the atrio-ventricular node modulation? (af-ablation.org)
Ventricles10
- The AV node lies at the lower back section of the interatrial septum near the opening of the coronary sinus, and conducts the normal electrical impulse from the atria to the ventricles. (wikipedia.org)
- This property is important because loss of the conduction system before the AV node should still result in pacing of the ventricles by the slower pacemaking ability of the AV node. (wikipedia.org)
- Atrioventricular conduction disease (AV block) describes impairment of the electrical continuity between the atria and ventricles. (wikipedia.org)
- When atrial fibrillation happens, the atria and the ventricles or the upper and the lower chambers of the heart would not be synchronized with one another. (medanta.org)
- The atrioventricular valves are valves between the atria and the ventricles. (merckvetmanual.com)
- The atrioventricular node is an area of specialized tissue between the atria and the ventricles of the heart , which conducts the normal electrical impulse from the atria to the ventricles. (wikidoc.org)
- During atrial fibrillation, the heart's upper chambers (the atria) beat chaotically and irregularly - out of sync with the lower chambers (the ventricles) of the heart. (seniorhealthcarematters.com)
- As the signal passes from the sinus node through the atria, they contract, pumping blood from your atria into the ventricles below. (seniorhealthcarematters.com)
- As the signal passes through the AV node to the ventricles, it signals the ventricles to contract, pumping blood out to your body. (seniorhealthcarematters.com)
- This rate is too fast to allow every impulse to be conducted through the atrioventricular node to the ventricles. (msdmanuals.com)
Afib3
- Atrial fibrillation (AFib) is an irregular and often very rapid heart rhythm. (mayoclinic.org)
- The treatments for AFib and atrial flutter are similar. (mayoclinic.org)
- Atrial fibrillation (AF or afib) is a type of heart rhythm disorder, or arrhythmia . (everydayhealth.com)
Nodal3
- The blood supply of the AV node is from the atrioventricular nodal branch. (wikipedia.org)
- Cystic tumour of atrioventricular nodal region (CTAVN) CTAVN is of endodermal origin and occurs exclusively in the area of the AV node, tricuspid valve, and interatrial septum. (wikipedia.org)
- The blood supply of the AV node is from a branch of the right coronary artery in 85% to 90% of individuals (a branch off of the posterolateral artery , the AV nodal artery , and from a branch of the left circumflex artery in 10% to 15% of individuals. (wikidoc.org)
Dofetilide3
- Dofetilide increased the atrial and ventricular effective refractory periods, as well as the antegrade and retrograde effective refractory period of the accessory pathway. (bmj.com)
- 9 , 10 Studies have shown that dofetilide prolongs both atrial and ventricular monophasic action potential durations and increases atrial and ventricular effective and functional refractory periods. (bmj.com)
- Because of its selective class III antiarrhythmic effect, dofetilide has no effect on atrioventricular conduction or sinus node function. (bmj.com)
Refractoriness1
- The proposed method enables analysis of circadian variation in AV node conduction delay and refractoriness from 24h ambulatory ECG, which can be used to monitor and possibly predict the effect of rate control drugs. (lu.se)
Congenital2
- Congenital complete atrioventricular block is a rare disorder with an incidence of 1 in 22,000 live births. (jpgo.org)
- 3] Congenital complete atrioventricular block may be diagnosed antenatally as early as 16 weeks gestation. (jpgo.org)
Chambers8
- The signal travels through the heart's upper chambers to the atrioventricular (AV) node. (mayoclinic.org)
- In atrial fibrillation, electrical signals fire from many locations in the upper chambers, causing them to beat chaotically. (mayoclinic.org)
- Since the AV node doesn't prevent all of these chaotic signals from entering the lower chambers, the heart beats faster and irregularly. (mayoclinic.org)
- During atrial fibrillation, the heart's upper chambers - called the atria - beat chaotically and irregularly. (mayoclinic.org)
- Atrial fibrillation is an irregular and often rapid heart rate that occurs when the two upper chambers of your heart (atria) experience chaotic electrical signals. (seniorhealthcarematters.com)
- Normally, the impulse travels first through the atria and then through a connecting pathway between the upper and lower chambers of your heart called the atrioventricular (AV) node. (seniorhealthcarematters.com)
- In atrial fibrillation, the upper chambers of your heart (atria) experience chaotic electrical signals. (seniorhealthcarematters.com)
- HN - 2008 BX - Lateral Sinus MH - Atrial Septum UI - D054087 MN - A07.541.459.249 MS - The thin membrane-like muscular structure separating the right and the left upper chambers (HEART ATRIA) of a heart. (bvsalud.org)
Electrical5
- It is also reported that human PITX2 insufficiency results in cellular and molecular changes leading to atrial electrical and structural remodeling linked to arrhythmogenesis 6 . (nature.com)
- In a typical heart, a tiny group of cells at the sinus node sends out an electrical signal. (mayoclinic.org)
- The His bundle is an isolated structure, a continuation of the AV node that provides a connection for the electrical impulse to travel from the AV node to the right and left ventricle via the right and left bundles, respectively. (acc.org)
- The resulting electrical activity is chaotic rather than organized and thus, the atrial walls quiver rather than contract. (msdmanuals.com)
- During atrial flutter, unlike in atrial fibrillation, electrical activity in the atria is coordinated. (msdmanuals.com)
Syndrome1
- The neonate was later incidentally diagnosed to have Down syndrome with atrial septal defect. (jpgo.org)
Conduction system1
- Such condition may be caused by dysfunctions of the sinu-atrial (SA) node, the atrio-ventricular (AV) node, or other parts of the heart's conduction system. (biotronik.com)
Symptoms8
- If you have symptoms of atrial fibrillation, make an appointment for a health checkup. (mayoclinic.org)
- The main goal of treatment for atrial fibrillation (AF) is to treat symptoms and/or arrhythmia-induced heart failure. (biomedcentral.com)
- What are the signs and symptoms of atrial fibrillation? (everydayhealth.com)
- Atrial fibrillation is considered to be a dangerous health condition, even if it doesn't cause symptoms. (everydayhealth.com)
- Atrial fibrillation causes noticeable symptoms in many people, but some experience no symptoms at all. (everydayhealth.com)
- What are the symptoms for atrial fibrillation? (seniorhealthcarematters.com)
- If you have any symptoms of atrial fibrillation, make an appointment with your doctor. (seniorhealthcarematters.com)
- Your doctor may order an electrocardiogram to determine if your symptoms are related to atrial fibrillation or another heart rhythm disorder (arrhythmia). (seniorhealthcarematters.com)
Treatment3
- Treatment for atrial fibrillation may include medicines, therapy to shock the heart back to a regular rhythm and procedures to block faulty heart signals. (mayoclinic.org)
- E. The chronic or long standing PSVT'S like atrial flutter or fibrillation do not revert without treatment,often fail to revert even with attempted treatment and if reverted will often recur despite therapy. (rjmatthewsmd.com)
- Although atrial flutter is a different arrhythmia, the treatment is quite similar to atrial fibrillation. (seniorhealthcarematters.com)
Heartbeat4
- She has atrial fibrillation or A-fib, a type of rapid, irregular heartbeat. (epnet.com)
- The normal range for heartbeat is 60-100 per minute, whereas during atrial fibrillation, your heartbeat could be in the range of 100-175 per minute. (medanta.org)
- The two primary goals for atrial fibrillation are resetting the rhythm of heartbeat and preventing blood clots. (medanta.org)
- The sinus node produces the impulse that normally starts each heartbeat. (seniorhealthcarematters.com)
Beats per mi3
- Atrial rates are generally between 240 and 360 beats per minute (bpm) without medications. (medscape.com)
- While a normal resting heart rate is 60 to 100 beats per minute (bpm), atrial fibrillation can cause your atria to beat 300 to 600 times per minute. (everydayhealth.com)
- For most people who are not being treated, every second atrial impulse gets to the ventricules, resulting in a ventricular rate of about 150 beats per minute. (msdmanuals.com)