NationMaster - Encyclopedia: Arrhythmogenic right ventricular dysplasia

Arrhythmogenic right ventricular dysplasia (ARVD, also known as arrhythmogenic right ventricular cardiomyopathy or ARVC) is a type of nonischemic cardiomyopathy that involves primarily the right ventricle. It is characterized by hypokinetic areas involving the free wall of the right ventricle, with fibrofatty replacement of the right ventricular myocardium, with associated arrhythmias originating in the right ventricle. The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). ... // I00-I99 - Diseases of the circulatory system (I00-I02) Acute rheumatic fever (I00) Rheumatic fever without mention of heart involvement (I01) Rheumatic fever with heart involvement (I02) Rheumatic chorea (I05-I09) Chronic rheumatic heart diseases (I05) Rheumatic mitral valve diseases (I050) Mitral stenosis (I051) Rheumatic mitral insufficiency (I06) Rheumatic aortic... The right ventricle is one of four chambers (two atria and two ventricles) in the human heart. ... Myocardium is the muscular tissue of the heart. ... A cardiac arrhythmia, also called cardiac dysrhythmia, is a disturbance in the regular rhythm of the heartbeat. ...

Overview

ARVD is an important cause of ventricular arrhythmias in children and young adults. It is seen predominantly in males, and 30-50% of cases have a familial distribution. It is usually inherited in an autosomal dominant pattern, with variable expression. The penetrance is 20-35% in general, but significantly higher in Italy. Seven gene loci have been implicated in ARVD. However, about 50% of families that express ARVD that undergo genetic screening do not show linkage with any of the known chromosomal loci. It is unclear whether the pathogenesis varies with the different loci involved. A standard genetic screening test is not available. It has been suggested that this article or section be merged into Dominance relationship. ... Penetrance is a term used in genetics that describes the extent to which the properties controlled by a gene, its phenotype, will be expressed. ... Figure 1: A representation of a condensed eukaryotic chromosome, as seen during cell division. ... For the hard rock band, see Allele (band). ...

Naxos Disease

Naxos disease is an autosomal recessive variant of ARVD, described initially on the Greek island of Naxos. There, the penetrance is >90%. It involves the gene that codes for plakoglobin (a protein that is involved in cellular adhesion), on chromosome 17p. Naxos disease is described as a triad of ARVD, palmoplantar keratosis, and wooly hair. The signs of Naxos disease are more severe than with autosomal dominant ARVD. In genetics, the term recessive gene refers to an allele that causes a phenotype (visible or detectable characteristic) that is only seen in a homozygous genotype (an organism that has two copies of the same allele). ... Naxos is the largest island (428 kmÂ² ) in the Cyclades island group in the Aegean Sea, which separates Greece and Turkey. ... Penetrance is a term used in genetics that describes the extent to which the properties controlled by a gene, its phenotype, will be expressed. ... Figure 1: A representation of a condensed eukaryotic chromosome, as seen during cell division. ... Keratosis can refer to: actinic keratosis (also known as solar keratosis) seborrheic keratosis keratosis pilaris (KP) Category: ‪Disambiguation‬ ...

Incidence

The incidence of ARVD is about 1/10,000 in the general population in the United States, although some studies have suggested that it may be as common as 1/1,000. It accounts for up to 17% of all sudden cardiac deaths in the young. In Italy, the incidence is 40/10,000, making it the most common cause of sudden cardiac death in the young population.

Presentation

Up to 80% of individuals with ARVD present with syncope or sudden cardiac death. The remainder frequently present with palpitations or other symptoms due to right ventricular outflow tract (RVOT) tachycardia (a type of monomorphic ventricular tachycardia). This article or section does not cite its references or sources. ...

Symptoms are usually exercise-related. In populations where hypertrophic cardiomyopathy is screened out prior to involvement in competitive athletics, it is a common cause of sudden cardiac death. Hypertrophic cardiomyopathy, or HCM, is a disease of the myocardium (the muscle of the heart) in which a portion of the myocardium is hypertrophied (thickened) without any obvious cause. ...

The first clinical signs of ARVD are usually during adolescence. However, signs of ARVD have been demonstrated in infants. Young Men Organization Teenager and Teen also redirect here. ...

Pathogenesis

The pathogenesis of ARVD is largely unknown. Apoptosis (programmed cell death) appears to play a large role. It is unclear why only the right ventricle is involved. The disease process starts in the subepicardial region and works its way towards the endocardial surface, leading to transmural involvement (possibly accounting for the aneurysmal dilatation of the RV). Residual myocardium is confined to the subendocardial region and the trabeculae of the RV. These trabeculae may become hypertrophied. A section of mouse liver showing an apoptotic cell indicated by an arrow // Apoptosis is a process of deliberate life relinquishment by a cell in a multicellular organism. ...

Aneurysmal dilatation is seen in 50% of cases at autopsy. It usually occurs in the diaphragmatic, apical, and infundibular regions (known as the triangle of dysplasia). The left ventricle is involved in 50-67% of individuals. If the left ventricle is involved, it is usually late in the course of disease, and confers a poor prognosis.

There are two pathological patterns seen in ARVD, Fatty infiltration and fibro-fatty infiltration.

Fatty infiltration

The first, fatty infiltration, is confined to the right ventricle. This involves a partial or near-complete substitution of myocardium with fatty tissue without wall thinning. It involves predominantly the apical and infundibular regions of the RV. The left ventricle and ventricular septum are usually spared. No inflammatory infiltrates are seen in fatty infiltration. There is evidence of myocyte (myocardial cell) degeneration and death seen in 50% of cases of fatty infiltration. Myocyte is the technical term for a muscle cell. ...

Fibro-fatty infiltration

The second, fibro-fatty infiltration, involves replacement of myocytes with fibrofatty tissue. A patchy myocarditis is involved in up to 2/3 of cases, with inflammatory infiltrates (mostly T cells) seen on microscopy. Myocardial atrophy is due to injury and apoptosis. This leads to thinning of the RV free wall (to < 3 mm thickness) Myocytes are replaced with fibrofatty tissue. The regions preferentially involved include the RV inflow tract, the RV outflow tract, and the RV apex. However, the LV free wall may be involved in some cases. Involvement of the ventricular septum is rare. The areas involved are prone to aneurysm formation. T cells are a subset of lymphocytes that play a large role in the immune response. ... A section of mouse liver showing an apoptotic cell indicated by an arrow // Apoptosis is a process of deliberate life relinquishment by a cell in a multicellular organism. ...

Ventricular arrhythmias

Ventricular arrhythmias due to ARVD typically arise from the diseased right ventricle. The type of arrhythmia ranges from frequent premature ventricular complexes (PVCs) to ventricular tachycardia (VT) to ventricular fibrillation (VF). Premature ventricular contraction (PVC), also known as ventricular premature beat (VPB) or extrasystole, is a form of irregular heartbeat in which the ventricle contracts prematurely. ... Ventricular tachycardia (V-tach or VT) is a fast rhythm that originates in one of the ventricles of the heart. ... Ventricular fibrillation (V-fib or VF) is a cardiac condition which consists of a lack of coordination of the contraction of the muscle tissue of the large chambers of the heart that eventually leads to the heart stopping altogether. ...

While the initiating factor of the ventricular arrhythmias is unclear, it may be due to triggered activity or reentry.

Ventricular arrhythmias are usually exercise-related, suggesting that they are sensitive to catecholamines. The ventricular beats typically have a right axis deviation. Multiple morphologies of ventricular tachycardia may be present in the same individual, suggesting multiple arrhythmogenic foci or pathways. Cardiac arrhythmia is a group of conditions in which the muscle contraction of the heart is irregular or is faster or slower than normal. ...

Right ventricular outflow tract (RVOT) tachycardia is the most common VT seen in individuals with ARVD. In this case, the EKG shows a left bundle branch block (LBBB) morphology with an inferior axis. ECG characteristics of a typical LBBB showing wide QRS complexes with abnormal morphology in leads V1 and V6. ...

Diagnosis

The tetralogy of Fallot is a congenital heart defect which classically has four anatomical components. ... Ebsteins anomaly is a congenital heart defect in which the opening of the tricuspid valve is displaced towards the apex of the right ventricle of the heart. ... Atrial septal defects (ASD) are a group of congenital heart diseases that enables communication between atria of the heart and may involve the interatrial septum. ...

Clinical testing

In order to make the diagnosis of ARVD, a number of clinical tests are employed, including the electrocardiogram (EKG), echocardiography, right ventricular angiography, and cardiac MRI. â€œQRSâ€ redirects here. ... An echocardiogram. ...

Electrocardiogram

90% of individuals with ARVD have some EKG abnormality. The most common EKG abnormality seen in ARVD is T wave inversion in leads V₁ to V₃. However, this is a non-specific finding, and may be considered a normal variant in right bundle branch block (RBBB), women, and children under 12 years old. Right bundle branch block (RBBB) is a cardiac conduction abnormality seen on electrocardiogram (EKG). ...

RBBB itself is seen frequently in individuals with ARVD. This may be due to delayed activation of the right ventricle, rather than any intrinsic abnormality in the right bundle branch.

The epsilon wave is found in about 50% of those with ARVD. This is described as a terminal notch in the QRS complex. It is due to slowed intraventricular conduction. The epsilon wave may be seen on a surface EKG; however, it is more commonly seen on signal averaged EKGs.

Ventricular ectopy seen on a surface EKG in the setting of ARVD is typically of left bundle branch block (LBBB) morphology, with a QRS axis of -90 to +110 degrees. The origin of the ectopic beats is usually from one of the three regions of fatty degeneration (the "triangle of dysplasia"): the RV outflow tract, the RV inflow tract, and the RV apex. Cardiac ectopy is a disturbance of the electrical conduction system of the heart, in which beats arise from the wrong part of the heart muscle. ... ECG characteristics of a typical LBBB showing wide QRS complexes with abnormal morphology in leads V1 and V6. ...

Signal averaged ECG

Signal averaged ECG (SAECG) is used to detect late potentials and epsilon waves in individuals with ARVD.

Echocardiography

Echocardiography may reveal an enlarged, hypokinetic right ventricle with a paper-thin RV free wall. The dilatation of the RV will cause dilatation of the tricuspid valve annulus, with subsequent tricuspid regurgitation.Paradoxical septal motion may also be present. Regurgitation is blood flow in the opposite direction from normal, as the backward flowing of blood into the heart or between heart chambers. ...

Cardiac MRI

Fatty infiltration of the RV free wall can be visible on cardiac MRI. Fat has increased intensity in T1-weighted images. However, it may be difficult to differentiate intramyocardial fat and the epicardial fat that is commonly seen adjacent to the normal heart. Also, the sub-tricuspid region may be difficult to distinguish from the atrioventricular sulcus, which is rich in fat.

Cardiac MRI can visualize the extreme thinning and akinesis of the RV free wall. However, the normal RV free wall may be about 3 mm thick, making the test less sensitive.

Right ventricular angiography

Right ventricular angiography is considered the gold standard for the diagnosis of ARVD. Findings consistent with ARVD are an akinetic or dyskinetic bulging localized to the infundibular, apical, and subtricuspid regions of the RV. The specificity is 90%; however, the test is observer dependent. In medicine, a gold standard test is the diagnostic test that is regarded as definitive in determining whether an individual has a disease process. ...

Right ventricular biopsy

Transvenous biopsy of the right ventricle can be highly specific for ARVD, but it has low sensitivity. False positives include other conditions with fatty infiltration of the ventricle, such as chronic alcohol abuse and Duschenne/Becker muscular dystrophy.

False negatives are common, however, because the disease progresses typically from the epicardium to the endocardium (with the biopsy sample coming from the endocardium), and the segmental nature of the disease. Also, due to the paper-thin right ventricular free wall that is common in this disease process, most biopsy samples are taken from the ventricular septum, which is commonly not involved in the disease process.

A biopsy sample that is consistent with ARVD would have > 3% fat, >40% fibrous tissue, and <45% myocytes.

Autopsy

A post mortem histological demonstration of full thickness substitution of the RV myocardium by fatty or fibro-fatty tissue is consistent with ARVD.

Diagnostic Criteria

There is no pathognomonic feature of ARVD. The diagnosis of ARVD is based on a combination of major and minor criteria. To make a diagnosis of ARVD requires either 2 major criteria or 1 major and 2 minor criteria or 4 minor criteria.

Minor Criteria In cardiovascular physiology, ejection fraction (Ef) is the fraction of blood pumped out of a ventricle with each heart beat. ...

Right bundle branch block (RBBB) is a cardiac conduction abnormality seen on electrocardiogram (EKG). ... ECG characteristics of a typical LBBB showing wide QRS complexes with abnormal morphology in leads V1 and V6. ...

Natural History

There is a long asymptomatic lead-time in individuals with ARVD. While this is a genetically transmitted disease, individuals in their teens may not have any characteristics of ARVD on screening tests.

Many individuals have symptoms associated with ventricular tachycardia, such as palpitations, light-headedness, or syncope. Others may have symptoms and signs related to right ventricular failure, such as lower extremity edema, liver congestion with elevated hepatic enzymes. Unfortunately, sudden death may be the first manifestation of disease.

ARVD is a progressive disease. Over time, the right ventricle becomes more involved, leading to right ventricular failure. The right ventricle will fail before there is left ventricular dysfunction. However, by the time the individual has signs of overt right ventricular failure, there will be histological involvement of the left ventricle. Eventually, the left ventricle will also become involved, leading to bi-ventricular failure. Signs and symptoms of left ventricular failure may become evident, including congestive heart failure, atrial fibrillation, and an increased incidence of thromboembolic events.

Management

The goal of management of ARVD is to decrease the incidence of sudden cardiac death. This raises a clinical dilemma: How to prophylactically treat the asymptomatic patient who was diagnosed during family screening.

A certain subgroup of individuals with ARVD are considered at high risk for sudden cardiac death. Characteristics associated with high risk of sudden cardiac death include:

Management options include pharmacological, surgical, catheter ablation, and placement of an implantable cardioverter-defibrillator. An implantable cardioverter-defibrillator (ICD), also known as an automated implantable cardioverter-defibrillator (AICD), is a device that is implanted under the skin of patients that are at risk of sudden cardiac death due to ventricular fibrillation. ...

Prior to the decision of the treatment option, programmed electrical stimulation in the electrophysiology laboratory may be performed for additional prognostic information. Goals of programmed stimulation include: An electrophysiologic study (EPS) is one of a number of tests of the electrical conduction system of the heart performed by a cardiac electrophysiologist, a specialist in the electrical conduction system of the heart. ... Cardiac electrophysiology is the science of the electric functioning of the heart. ...

Regardless of the management option chosen, the individual is typically suggested to undergo lifestyle modification, including avoidance of strenuous exercise, cardiac stimulants (ie: caffeine, nicotine, pseudoephedrine) and alcohol. If the individual wishes to begin an exercise regimen, an exercise stress test may have added benefit.

Pharmacologic management

Pharmacologic management of ARVD involves arrhythmia suppression and prevention of thrombus formation.

Sotalol, a beta blocker and a class III antiarrhythmic agent, is the most effective antiarrhythmic agent in ARVD. Other antiarrhythmic agents used include amiodarone and conventional beta blockers (ie: metoprolol). If antiarrhythmic agents are used, their efficacy should be guided by series ambulatory holter monitoring, to show a reduction in arrhythmic events. Sotalol is a drug used in individuals with rhythm disturbances (cardiac arrhythmias) of the heart. ... Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ... Antiarrhythmic agents are a group of pharmaceuticals that are used to suppress fast rhythms of the heart (cardiac arrhythmias), such as atrial fibrillation, atrial flutter, ventricular tachycardia, and ventricular fibrillation. ... Amiodarone belongs to a class of drugs called Vaughan-Williams Class III antiarrhythmic agent. ...

While angiotensin converting enzyme inhibitors (ACE Inhibitors) are well known for slowing progression in other cardiomyopathies, they have not been proven to be helpful in ARVD. ACE inhibitors, or inhibitors of Angiotensin_Converting Enzyme, are a group of pharmaceuticals that are used primarily in treatment of hypertension and congestive heart failure, in most cases as the drugs of first choice. ...

Individuals will decreased RV ejection fraction with dyskinetic portions of the right ventricle may benefit from long term anticoagulation with warfarin to prevent thrombus formation and subsequent pulmonary embolism. Warfarin (also known under the brand names of Coumadin, Jantoven, Marevan, and Waran) is an anticoagulant medication that is administered orally or, very rarely, by injection. ...

Catheter ablation

Catheter ablation may be used to treat intractable ventricular tachycardia. It has a 60-90% success rate.^[1] Unfortunately, due to the progressive nature of the disease, recurrence is common (60% recurrence rate), with the creation of new arrhythmogenic foci. Indications for catheter ablation include drug-refractory VT and frequent recurrence of VT after ICD placement, causing frequent discharges of the ICD. An implantable cardioverter-defibrillator (ICD), also known as an automated implantable cardioverter-defibrillator (AICD), is a device that is implanted under the skin of patients that are at risk of sudden cardiac death due to ventricular fibrillation. ...

Implantable cardioverter-defibrillator

An ICD is the most effective prevention against sudden cardiac death. Due to the prohibitive cost of ICDs, they are not routinely placed in all individuals with ARVD. An implantable cardioverter-defibrillator (ICD), also known as an automated implantable cardioverter-defibrillator (AICD), is a device that is implanted under the skin of patients that are at risk of sudden cardiac death due to ventricular fibrillation. ...

Since ICDs are typically placed via a transvenous approach into the right ventricle, there are complications associated with ICD placement and follow-up.

Due to the extreme thinning of the RV free wall, it is possible to perforation the RV during implantation, potentially causing pericardial tamponade. Because of this, every attempt is made at placing the defibrillator lead on the ventricular septum. Cardiac tamponade, also known as pericardial tamponade, is a medical emergency condition where liquid accumulates in the pericardium in a relatively short time. ...

After a successful implantation, the progressive nature of the disease may lead to fibro-fatty replacement of the myocardium at the site of lead placement. This may lead to undersensing of the individual's electrical activity (potentially causing inability to sense VT or VF), and inability to pace the ventricle.

Cardiac transplant surgery

Cardiac transplant surgery is rarely performed in ARVD. It may be indicated if the arrhythmias associated with the disease are uncontrollable or if there is severe bi-ventricular heart failure that is not manageable with pharmacological therapy.

Family screening

All first degree family members of the affected individual should be screened for ARVD. This is used to establish the pattern of inheritance. Screening should begin during the teenage years unless otherwise indicated. Screening tests include:

References

1. Fontaine G, Gallais Y, Fornes P, Hebert JL, Frank R. Arrhythmogenic right ventricular dysplasia/cardiomyopathy. Anesthesiology. 2001 Jul;95(1):250-4. (Medline abstract)

2. Corrado D, Basso C, Thiene G. Arrhythmogenic right ventricular cardiomyopathy: diagnosis, prognosis, and treatment. Heart. 2000 May;83(5):588-95. (Medline abstract)

3. McRae AT 3rd, Chung MK, Asher CR. Arrhythmogenic right ventricular cardiomyopathy: a cause of sudden death in young people. Cleve Clin J Med. 2001 May;68(5):459-67. (Medline abstract)

External links

Category: Cardiomyopathy Diagram of the human circulatory system. ... Pathology (from Greek pathos, feeling, pain, suffering; and logos, study of; see also -ology) is the study of the processes underlying disease and other forms of illness, harmful abnormality, or dysfunction. ... This article or section does not cite any references or sources. ... In kidney, as a result of benign arterial hypertension, hyaline (pink, amorphous, homogeneous material) accumulates in the wall of small arteries and arterioles, producing the thickening of their walls and the narrowing of the lumens - hyaline arteriolosclerosis. ... While most forms of hypertension have no known underlying cause (and are thus known as essential hypertension or primary hypertension), in about 10% of the cases, there is a known cause, and thus the hypertension is secondary hypertension (or, less commonly, inessential hypertension). ... Renovascular hypertension (or renal hypertension) is a form of secondary hypertension. ... It has been suggested that this article or section be merged with Coronary heart disease. ... Prinzmetals angina, also known as variant angina or angina inversa, is a syndrome typically consisting of angina (cardiac chest pain) at rest that occurs in cycles. ... Acute myocardial infarction (AMI or MI), more commonly known as a heart attack, is a disease state that occurs when the blood supply to a part of the heart is interrupted. ... Dresslers syndrome is a form of pericarditis that occurs in the setting of injury to the heart or the pericardium (the outer lining of the heart). ... Pulmonary circulation is the portion of the cardiovascular system which carries oxygen-depleted blood away from the heart, to the lungs, and returns oxygenated blood back to the heart. ... Cor pulmonale is a medical term used to describe a change in structure and function of the right ventricle of the heart as a result of a respiratory disorder. ... The pericardium is a double-walled sac that contains the heart and the roots of the great vessels. ... Pericarditis is inflammation of the sac surrounding the heart, the pericardium. ... Cardiac tamponade, also known as pericardial tamponade, is a medical emergency condition where liquid accumulates in the pericardium in a relatively short time. ... In the heart, the endocardium is the innermost layer of tissue that lines the chambers of the heart. ... Grays Fig. ... Endocarditis is an inflammation of the inner layer of the heart, the endocardium. ... Mitral regurgitation (MR), also known as mitral insufficiency, is the abnormal leaking of blood through the mitral valve, from the left ventricle into the left atrium of the heart. ... Mitral valve prolapse (MVP) is a heart valve condition marked by the displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole. ... Mitral stenosis is a narrowing of the orifice of the mitral valve of the heart. ... Aortic valve stenosis (AS) is a heart condition caused by the incomplete opening of the aortic valve. ... Aortic insufficiency (AI), also known as aortic regurgitation (AR), is the leaking of the aortic valve of the heart that causes blood to flow in the reverse direction during ventricular diastole, from the aorta into the left ventricle. ... Pulmonary valve stenosis is a medical condition in which outflow of blood from the right ventricle of the heart is obstructed at the level of the pulmonic valve. ... Myocardium is the muscular tissue of the heart. ... In medicine (cardiology), myocarditis is inflammation of the myocardium, the muscular part of the heart. ... Dilated cardiomyopathy or DCM (also known as congestive cardiomyopathy), is a disease of the myocardium (the muscle of the heart) in which a portion of the myocardium is dilated, often without any obvious cause. ... Hypertrophic cardiomyopathy, or HCM, is a disease of the myocardium (the muscle of the heart) in which a portion of the myocardium is hypertrophied (thickened) without any obvious cause. ... Restrictive cardiomyopathy (RCM) is the least common cardiomyopathy. ... The normal electrical conduction in the heart allows the impulse that is generated by the sinoatrial node (SA node) of the heart to be propagated to (and stimulate) the myocardium (Cardiac muscle). ... First degree AV block or PR prolongation is a disease of the electrical conduction system of the heart in which the PR interval is lengthened. ... Second degree AV block is a disease of the electrical conduction system of the heart. ... Third degree AV block, also known as complete heart block, is a defect of the electrical system of the heart, in which the impulse generated in the atria (typically the SA node on top of the right atrium) does not propagate to the ventricles. ... Bundle branch block refers to a disorder of the hearts electrical conducting system. ... ECG characteristics of a typical LBBB showing wide QRS complexes with abnormal morphology in leads V1 and V6. ... Right bundle branch block (RBBB) is a cardiac conduction abnormality seen on electrocardiogram (EKG). ... Bifascicular block is a conduction abnormality in the heart where two of the three main fascicles of the His/Purkinje system are blocked. ... Trifascicular heart block is the triad of first degree heart block, right bundle branch block, and either left anterior or left posterior hemi block seen on an electrocardiogram (EKG). ... Wolff-Parkinson-White syndrome (WPW) is a syndrome of pre-excitation of the ventricles of the heart due to an accessory pathway known as the Bundle of Kent. ... Lown-Ganong-Levine syndrome (LGL) is a syndrome of pre-excitation of the ventricles due to an accessory pathway providing an abnormal electrical communication from the atria to the ventricles. ... The long QT syndrome (LQTS) is a heart disease in which there is an abnormally long delay between the electrical excitation (or depolarization) and relaxation (repolarization) of the ventricles of the heart. ... This article or section does not cite any references or sources. ... A supraventricular tachycardia (SVT) is a rapid rhythm of the heart in which the origin of the electrical signal is either the atria or the AV node. ... AV nodal reentrant tachycardia (AVNRT) is a type of reentrant tachycardia (fast rhythm) of the heart. ... Ventricular tachycardia (V-tach or VT) is a fast rhythm that originates in one of the ventricles of the heart. ... Atrial flutter is a rhythmic, fast rhythm that occurs in the atria of the heart. ... Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ... Ventricular fibrillation (V-fib or VF) is a cardiac condition which consists of a lack of coordination of the contraction of the muscle tissue of the large chambers of the heart that eventually leads to the heart stopping altogether. ... pac This page meets Wikipedias criteria for speedy deletion. ... Premature ventricular contraction (PVC), also known as ventricular premature beat (VPB) or extrasystole, is a form of irregular heartbeat in which the ventricle contracts prematurely. ... Sick sinus syndrome, also called Bradycardia-tachycardia syndrome is a group of abnormal heartbeats (arrhythmias) presumably caused by a malfunction of the sinus node, the hearts natural pacemaker. ... Cardiomegaly is a medical condition wherein the heart is enlarged. ... Although ventricular hypertrophy may occur in either the left or right or both ventricles of the heart , left ventricular hypertrophy (LVH) is more commonly encountered. ... Left ventricular hypertrophy (LVH) is the abnormal thickening of the myocardium (muscle) of the left ventricle of the heart. ... Right ventricular hypertrophy (RVH) is a form of ventricular hypertrophy affecting the right ventricle. ... Section of an artery An artery or arterial is also a class of highway. ... An arteriole is a blood vessel that extends and branchs out from an artery and leads to capillaries. ... The word capillary is used to describe any very narrow tube or channel through which a fluid can pass. ... Renal artery stenosis is the narrowing of the renal artery. ... Aortic dissection is a tear in the wall of the aorta (the largest artery of the body). ... Raynauds phenomenon (RAY-noz), in medicine, is a vasospastic disorder causing discoloration of the fingers, toes, and occasionally other extremities, named for French physician Maurice Raynaud (1834 - 1881). ... Raynauds disease (RAY-noz) is a condition that affects blood flow to the extremities which include the fingers, toes, nose and ears when exposed to temperature changes or stress. ... Buergers disease (also known as thromboangiitis obliterans) is an acute inflammation and thrombosis (clotting) of arteries and veins of the hands and feet. ... Intermittent claudication is a cramping sensation in the legs that is present during exercise or walking and occurs as a result of decreased oxygen supply. ... In medicine, hereditary hemorrhagic telangiectasia (HHT), also known as Rendu-Osler-Weber syndrome, is a genetic disorder that leads to vascular malformations. ... In the circulatory system, a vein is a blood vessel that carries blood toward the heart. ... Lymph originates as blood plasma lost from the circulatory system, which leaks out into the surrounding tissues. ... Lymph nodes are components of the lymphatic system. ... Thrombosis is the formation of a clot or thrombus inside a blood vessel, obstructing the flow of blood through the circulatory system. ... Phlebitis is an inflammation of a vein, usually in the legs. ... This article is about Deep-vein thrombosis. ... A venous thrombosis is a blood clot that forms within a vein. ... In medicine (gastroenterology and hepatology), Budd-Chiari syndrome is the clinical picture caused by occlusion of the hepatic vein. ... It has been suggested that this article or section be merged into deep vein thrombosis. ... Paget-Schroetter disease (also Paget-von SchrÃ¶tter disease) refers to deep vein thrombosis of an upper extremity vein, including the axillary vein or subclavian vein. ... Vein gymnastics in the barefoot park Dornstetten, Germany. ... This article or section is in need of attention from an expert on the subject. ... In medicine (gastroenterology), esophageal varices are extreme dilations of sub mucosal veins in the mucosa of the esophagus in diseases featuring portal hypertension, secondary to cirrhosis primarily. ... Cross section showing the pampiniform plexus Varicocele is an abnormal enlargement of the veins in the scrotum draining the testicles. ... Gastric varices are dilated submucosal veins in the stomach. ... Caput medusae means dilated veins around the umbilicus. ... Superior vena cava syndrome (SVCS) is a result of obstruction of the superior vena cava. ... Lymphadenopathy is swelling of one or more lymph nodes. ... Lymphedema (AmE), also known as Lymphoedema (BrE), or lymphatic obstruction, is a condition of localized fluid retention caused by a compromised lymphatic system. ...

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