FACTOID # 22: South Dakota has the highest employment ratio in America, but the lowest median earnings of full-time male employees.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Hypertrophic cardiomyopathy
Hypertrophic cardiomyopathy
Classifications and external resources
ICD-10 I42.1-I42.2
ICD-9 425.4
DiseasesDB 6373
MedlinePlus 000192
eMedicine med/290  ped/1102 radio/129

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.1,10,22,29-31 Though perhaps most famous as a leading cause of sudden cardiac death in young athletes2 HCM's more important significance is as a cause of sudden unexpected cardiac death in any age group and as a cause of disabling cardiac symptoms. The International Statistical Classification of Diseases and Related Health Problems (commonly known by the abbreviation ICD) is a detailed description of known diseases and injuries. ... The following codes are used with International Statistical Classification of Diseases and Related Health Problems. ... The International Statistical Classification of Diseases and Related Health Problems (commonly known by the abbreviation ICD) is a detailed description of known diseases and injuries. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... The Diseases Database is a free website that provides information about the relationships between medical conditions, symptoms, and medications. ... MedlinePlus (medlineplus. ... eMedicine is an online clinical medical knowledge base that was founded in 1996. ... A top-down view of skeletal muscle Muscle (from Latin musculus little mouse [1]) is contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. ... The heart and lungs, from an older edition of Grays Anatomy. ... Myocardium is the muscular tissue of the heart. ... Left ventricular hypertrophy (LVH) is the abnormal thickening of the myocardium (muscle) of the left ventricle of the heart. ... A cardiac arrest is the cessation of normal circulation of the blood due to failure of the ventricles of the heart to contract effectively during systole. ...


A cardiomyopathy is any disease that primarily affects the muscle of the heart. In HCM, the normal alignment of muscle cells is disrupted, a phenomenon known as myocardial disarray. HCM also causes disruptions of the electrical functions of the heart. HCM is believed to be due to a mutation in one of many genes that results in a mutated myosin heavy chain, one of the components of the myocyte (the muscle cell of the heart). Depending on the degree of obstruction of the outflow of blood from the left ventricle of the heart, HCM can be defined as obstructive or non-obstructive. Myocardial disarray, also known as myocyte disarray, is a term to describe the loss of the normal parallel alignment of myocytes (the muscle cells of the heart). ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... Myocyte is the technical term for a muscle cell. ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... In the heart, a ventricle is a chamber which collects blood from an atrium (another heart chamber) and pumps it out of the heart. ...


HCM is also known as idiopathic hypertrophic subaortic stenosis (IHSS) and hypertrophic obstructive cardiomyopathy (HOCM). A non-obstructive variant of HCM is apical hypertrophic cardiomyopathy 3, which is also known as nonobstructive hypertrophic cardiomyopathy and Japanese variant hypertrophic cardiomyopathy (since the first cases described were all in individuals of Japanese descent). Idiopathic means arising spontaneously or from an obscure or unknown cause. ...


While most literature so far focuses on European, American, and Japanese populations, HCM appears in all racial groups. The incidence of HCM is about 0.2% to 0.5% of the general population.

Contents

Genetics

Hypertrophic cardiomyopathy is attributed to mutation in one of a number of genes that encode for one of the sarcomere proteins (usually effecting either the α or β myosin heavy chain on chromosome 14 q11.2-3). While the severity of the disease process is dependent on the particular gene mutation, about 80% of cases are inherited in an autosomal dominant pattern. Other gene mutations that are associated with HCM include mutations in α-tropomyosin (on chromosome 15), troponin T (on chromosome 1), Troponin I (on chromosome 14), and myosin-binding protein C (on chromosome 11). The prognosis is variable, based on the gene mutation. Image of sarcomere A sarcomere is the basic unit of a cross striated muscles myofibril. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Myosin is a motor protein filament found in muscle tissue. ... Figure 1: Chromosome. ... An autosomal dominant gene is one that occurs on an autosomal (non-sex determining) chromosome. ...


The MYH7 gene (encoding the Β-myosin heavy chain) was the first specific gene identified in familial hypertrophic cardiomyopathy. About 50 percent of all familial cases involve mutation in the MYH7 gene. In individuals without a family history of HCM, the most common cause of the disease is also mutations of the gene that produces the β-myosin heavy chain. Many different mutations in this gene have been identified, and the prognosis is dependent on the particular mutation. MYH7 is a gene associated with the generation of myosin. ...


An insertion/deletion polymorphism in the gene encoding for angiotensin converting enzyme (ACE) has been associated with some cases of HCM. The D/D (deletion/deletion) genotype of ACE is associated with more marked hypertrophy of the left ventricle and may be associated with higher risk of adverse outcomes.8,9 This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... Angiotensin-Converting Enzyme (ACE, EC 3. ...


Anatomic characteristics

Individuals with HCM have some degree of left ventricular hypertrophy. Usually this is an asymmetric hypertrophy, involving the inter-ventricular septum, and is known as asymmetric septal hypertrophy (ASH). This is in contrast to the concentric hypertrophy seen in aortic stenosis or hypertension. About 2/3 of individuals with HCM have asymmetric septal hypertrophy. Left ventricular hypertrophy (LVH) is the abnormal thickening of the myocardium (muscle) of the left ventricle of the heart. ... Aortic valve stenosis (AS) is a heart condition caused by the incomplete opening of the aortic valve. ... For other forms of hypertension see hypertension (disambiguation). ...


Many individuals with HCM demonstrate an obstruction to the outflow of blood from the left ventricle. This is known as dynamic outflow obstruction, because the degree of obstruction is variable and is dependent on the amount of blood in the ventricle immediately before ventricle systole (contraction). Systole can mean the following: Systole (medicine) is a term describing the contraction of the heart. ...


Dynamic outflow obstruction

Systolic anterior motion of the mitral valve

Echocardiogram demonstrating systolic anterior motion of the anterior leaflet of the mitral valve

Dynamic outflow obstruction (when present in HCM) is usually due to systolic anterior motion (SAM) of the anterior leaflet of the mitral valve. Systolic anterior motion of the mitral valve (SAM) was initially thought to be due to the septal subaortic bulge, narrowing the outflow tract, causing high velocity flow and a Venturi effect - a local underpressure in the outflow tract. Low pressure was thought to suck the mitral valve anteriorly into the septum. But SAM onset is observed to be a low velocity phenomenon: SAM begins at velocities no different from those measured in normals (11,12). Hence, the magnitude and importance of Venturi forces in the outflow tract are much less than previously thought, and Venturi forces cannot be the main force that initiates SAM. Recent echocardiographic evidence indicates that drag, the pushing force of flow is the dominant hydrodynamic force on the mitral leaflets (11-16). In obstructive HCM the mitral leaflets are often large (17) and are anteriorly positioned in the LV cavity (11,18) due to anteriorly positioned papillary muscles (11) that at surgery are often “agglutinated” onto the LV anterior wall by abnormal attachments (15,16). The mid-septal bulge aggravates the malposition of the valve and redirects outflow so that it comes from a lateral and posterior direction (13). The abnormally directed outflow may be visualized behind and lateral to the enlarged mitral valve, where it catches it, and pushes it into the septum (11-14). There is a crucial overlap between the inflow and outflow portions of the left ventricle (19). As SAM progresses in early systole the angle between outflow and the protruding mitral leaflet increases. A greater surface area of the leaflets is now exposed to drag which amplifies the force on the leaflets - drag increases with increasing angle relative to flow (13). An analogy is an open door in a drafty corridor: the door starts by moving slowly and then accelerates as it presents a greater surface area to the wind and finally it slams shut. The necessary conditions that predispose to SAM are: anterior position of the mitral valve in the LV, altered LV geometry that allows flow to strike the mitral valve from behind, and chordal slack (11-14). SAM may considered anteriorly directed mitral prolapse (12-14). In both conditions the mitral valve is enlarged and is displaced in systole by the pushing force of flow resulting in mitral regurgitation. The mitral valve, also known as the bicuspid valve, is a valve in the heart that lies between the left atrium (LA) and the left ventricle (LV). ...


Because the mitral valve leaflet doesn't get pulled into the LVOT until after the aortic valve opens, the initial upstroke of the arterial pulse will be normal. When the mitral valve leaflet gets pushed into the LVOT, the arterial pulse will momentarily collapse and be followed by a second rise, as the left ventricular pressure overcomes the increased obstruction that SAM of the mitral valve causes. This can be seen on the physical examination as a double tap upon palpation of the apical impulse and as a double pulsation upon palpation of the carotid pulse, known as pulsus bisferiens. In medicine, pulsus bisferiens, also bisferious pulse, is a sign where, on palpation of the pulse, a double peak per cardiac cycle can be appreciated. ...


Associated symptoms

The clinical course of HCM is variable. Many patients are asymptomatic or mildly symptomatic. The symptoms of HCM include shortness of breath, chest pain (sometimes known as angina), uncomfortable awareness of the heart beat (palpitations), lightheadedness, fatigue, fainting (called syncope) and sudden cardiac death. Dyspnea is largely due to increased stiffness of the left ventricle, which impairs filling of the ventricles and leads to elevated pressure in the left ventricle and left atrium. Symptoms are not closely related to the presence or severity of an outflow tract gradient (33). The term symptom (from the Greek syn = con/plus and pipto = fall, together meaning co-exist) has two similar meanings in the context of physical and mental health: Strictly, a symptom is a sensation or change in health function experienced by a patient. ... angina tonsillaris see tonsillitis. ... Heart rate is a term used to describe the frequency of the cardiac cycle. ... A palpitation is an abnormal, rapid beating of the heart, brought on by overexertion, disease or drugs. ... Light-headedness is a common and often unpleasant sensation of dizziness and/or feeling that one may be about to faint, which may be transient, recurrent, or occasionally chronic. ... Syncope may also refer to a linguistic phenomenon. ... Syncope has two distinct and apparantly unrelated meanings, one in linguistics and another in medicne. ... A cardiac arrest is the cessation of normal circulation of the blood due to failure of the ventricles of the heart to contract effectively during systole. ... Dyspnea (Latin dyspnoea, Greek dyspnoia from dyspnoos, short of breath) or shortness of breath (SOB) is perceived difficulty breathing or pain on breathing. ...


Risk factors for sudden death in individuals with HCM include a young age at first diagnosis (age < 30 years), an episode of aborted sudden death, a family history of HCM with sudden death of relatives, specific mutations in the genes encoding for troponin T and myosin, sustained supraventricular or ventricular tachycardia, recurrent syncope, ventricular septal wall thickness over 3 cm, hypotensive response to exercise, syncope (especially in children, and bradyarrhythmias (slow rhythms of the heart).4 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. ... Tachycardia is an abnormally rapid beating of the heart, defined as a resting heart rate of over 100 beats per minute. ... Syncope has two distinct and apparantly unrelated meanings, one in linguistics and another in medicne. ... Syncope has two distinct and apparantly unrelated meanings, one in linguistics and another in medicne. ...


Physical examination

Differentiating hypertrophic cardiomyopathy and valvular aortic stenosis
Aortic stenosis Hypertrophic cardiomyopathy
Echocardiography
Aortic valve calcification Common No
Dilated ascending aorta Common Rare
Ventricular hypertrophy Concentric LVH Asymmetric, often involving the septum
Physical examination
Murmur of AI Common No
Pulse pressure after PVC Increased Decreased
Valsalva maneuver Decreased intensity of murmur Increased intensity of murmur
Carotid pulsation Normal or tardus et parvus Brisk, jerky

The physical findings of HCM are associated with the dynamic outflow obstruction that is often present with this disease. Left ventricular hypertrophy (LVH) is the abnormal thickening of the myocardium (muscle) of the left ventricle of the heart. ... 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. ... Premature ventricular cantraction in an ECG (arrwos) 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. ... A Valsalva maneuver is any attempted exhalation against a closed glottis or against a closed mouth and nose. ... In medicine, pulsus tardus et parvus, is a sign where, on palpation of the pulse, the pulse is late (tardus) (relative to contraction of the heart) and weak/small (parvus). ...


Upon auscultation, the cardiac murmur will sound similar to the murmur of aortic stenosis. However, this murmur will increase in intensity with any maneuver that decreases the volume of blood in the left ventricle (such as standing or the strain phase of a Valsalva maneuver). Auscultation is the technical term for listening to the internal sounds of the body, usually using a stethoscope. ... Front of thorax, showing surface relations of bones, lungs (purple), pleura (blue), and heart (red outline). ... Aortic valve stenosis (AS) is a heart condition caused by the incomplete opening of the aortic valve. ... A Valsalva maneuver is any attempted exhalation against a closed glottis or against a closed mouth and nose. ...


If dynamic outflow obstruction exists, physical examination findings that can be elicited include the pulsus bisferiens and the double apical impulse with each ventricular contraction. These findings, when present, can help differentiate HCM from aortic stenosis. In addition, if the individual has premature ventricular contractions (PVCs), the change in the carotid pulse intensity in the beat after the PVC can help differentiate HCM from aortic stenosis. In individuals with HCM, the pulse pressure will decrease in the beat after the PVC, while in aortic stenosis, the pulse pressure will increase. Aortic valve stenosis (AS) is a heart condition caused by the incomplete opening of the aortic valve. ... Premature ventricular cantraction in an ECG (arrwos) 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. ...


Diagnostic testing

A diagnosis of hypertrophic cardiomyopathy is based upon a number of features of the disease process. While there is use of echocardiography, cardiac catheterization, or cardiac MRI in the diagnosis of the disease, other important factors include ECG findings and if there is any family history of HCM or unexplained sudden death in otherwise healty individuals. Diagnosis (from the Greek words dia = by and gnosis = knowledge) is the process of identifying a disease by its signs, symptoms and results of various diagnostic procedures. ... The echocardiogram is an ultrasound of the heart. ... Cardiac catheterization (heart cath) is the insertion of a catheter into a chamber or vessel of the heart. ... The mri are a fictional alien species in the Faded Sun Trilogy of C.J. Cherryh. ... Lead II An electrocardiogram (ECG or EKG, abbreviated from the German Elektrokardiogramm) is a graphic produced by an electrocardiograph, which records the electrical voltage in the heart in the form of a continuous strip graph. ...


Cardiac catheterization

Pressure tracings demonstrating the Brockenbrough-Braunwald-Morrow sign
Pressure tracings demonstrating the Brockenbrough-Braunwald-Morrow sign
AO = Descending aorta; LV = Left ventricle; ECG = Electrocardiogram.

After the third QRS complex, the ventricle has more time to fill. Since there is more time to fill, the left ventricle will have more volume at the end of diastole (increased preload). Due to the Frank-Starling law of the heart, the contraction of the left ventricle (and pressure generated by the left ventricle) will be greater on the subsequent beat (beat #4 in this picture). Because of the dynamic nature of the outflow obstruction in HCM, the obstruction increases more that the left ventricular pressure increase. This causes a fall in the aortic pressure as the left ventricular pressure rises (seen as the yellow shaded area in the picture). Download high resolution version (791x680, 198 KB)An intraventricular pressure tracing in an individual with hypertrophic cardiomyopathy, demonstrating dynamic outflow tract gradient File links The following pages link to this file: Hypertrophic cardiomyopathy ... Lead II An electrocardiogram (ECG or EKG, abbreviated from the German Elektrokardiogramm) is a graphic produced by an electrocardiograph, which records the electrical voltage in the heart in the form of a continuous strip graph. ... Diastole is the period of time when the heart relaxes after contraction. ... Heart during ventricular diastole. ... The Frank-Starling law of the heart (also known as Starlings law) states that the more the ventricle is filled with blood during diastole (end-diastolic volume), the greater the volume of ejected blood will be during the resulting systolic contraction (stroke volume). ...

Upon cardiac catheterization, catheters can be placed in the left ventricle and the ascending aorta, to measure the pressure difference between these structures. In normal individuals, during ventricular systole, the pressure in the ascending aorta and the left ventricle will equalize, and the aortic valve is open. In individuals with aortic stenosis or with HCM with an outflow tract gradient, there will be a pressure gradient (difference) between the left ventricle and the aorta, with the left ventricular pressure higher than the aortic pressure. This gradient represents the degree of obstruction that has to be overcome in order to eject blood from the left ventricle. Cardiac catheterization (heart cath) is the insertion of a catheter into a chamber or vessel of the heart. ... Catheter disassembled In medicine, a catheter is a tube that can be inserted into a body cavity duct or vessel. ... The largest artery in the human body, the aorta originates from the left ventricle of the heart and brings oxygenated blood to all parts of the body in the systemic circulation. ... Systole can mean the following: Systole (medicine) is a term describing the contraction of the heart. ... Aortic valve stenosis (AS) is a heart condition caused by the incomplete opening of the aortic valve. ...


The Brockenbrough-Braunwald-Morrow sign is observed in individuals with HCM with outflow tract gradient. This sign can be used to differentiate HCM from aortic stenosis. In individuals with aortic stenosis, after a premature ventricular contraction (PVC), the following ventricular contraction will be more forceful, and the pressure generated in the left ventricle will be higher. Because of the fixed obstruction that the stenotic aortic valve represents, the post-PVC ascending aortic pressure will increase as well. In individuals with HCM, however, the degree of obstruction will increase more than the force of contraction will increase in the post-PVC beat. The result of this is that the left ventricular pressure increases and the ascending aortic pressure decreases, with an increase in the LVOT gradient. Premature ventricular cantraction in an ECG (arrwos) 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. ...


While the Brockenbrough-Braunwald-Morrow sign is most dramatically demonstrated using simultaneous intra-cardiac and intra-aortic catheters, it can be seen on routine physical examination as a decrease in the pulse pressure in the post-PVC beat in individuals with HCM.


Treatment

In all patients with hypertrophic cardiomyopathy risk stratification is essential to attempt to ascertain which patients are at risk for sudden cardiac death (10,30). In those patients deemed to be at high risk the benefits and infrequent complications of defibrillator therapy are discussed; devices have been implanted in as many as 15% of patients at HCM centers. Treatment symptoms of obstructive HCM is directed towards decreasing the left ventricular outflow tract gradient and symptoms of dyspnea, chest pain and syncope. Medical therapy is successful in the majority of patients. The first medication that is routinely used is beta-blockade (metoprolol, atenolol, bisoprolol, propranolol) (10). If symptoms and gradient persist disopyramide may be added to the beta-blocker (28). Alternately verapamil may be substituted for beta-blockade. It should be stressed that most patient's symptoms may be managed medically without needing to resort to inteventions such as surgical septal myectomy, alcohol septal ablation or pacing. Severe symptoms in non-obstructive HCM may actually be more difficult to treat because there is no obvious target (obstruction) to treat. Medical therapy with verapamil, beta-blockade and diuretics may improve symptoms. Metoprolol is a beta blocker drug used in treatment of several diseases of the cardiovascular system. ... Atenolol is a drug belonging to the group of beta blockers, a class of drugs used primarily in cardiovascular diseases. ... Bisoprolol is a drug belonging to the group of beta blockers, a class of drugs used primarily in cardiovascular diseases. ... Propranolol (INN) (IPA: ) is a non-selective beta blocker mainly used in the treatment of hypertension. ... Verapamil (brand names: Isoptin®, Verelan®, Calan®) is a medical drug that acts as an L-type calcium channel blocker. ... A diuretic is any drug that tends to increase the flow of urine from the body (diuresis). ...


Surgical septal myectomy is the gold standard for relief of symptoms for patients who do not experience relief of symptoms from medications (10,22,25,28,30.31). It has been performed successfully for more than 25 years. Surgical septal myectomy uniformly decreases left ventricular outflow tract obstruction and improves symptoms, and in experienced centers has a surgical mortality of 1%. It involves a midline thoracotomy (general anesthesia, opening the chest, and cardiopulmonary bypass) and removing a portion of the interventricular septum (10). Surgical myectomy resection focused just on the subaortic septum, to increase the size of the outflow tract to reduce Venturi forces may be inadequate to abolish systolic anterior motion (SAM) of the anterior leaflet of the mitral valve. With this limited sort of resection the residual mid-septal bulge still redirects flow posteriorly: SAM persists because flow still gets behind the mitral valve. It is only when the deeper portion of the septal bulge is resected that flow is redirected anteriorly away from the mitral valve, abolishing SAM (21,22). With this in mind, a modification of the Morrow myectomy termed extended myectomy, mobilization and partial excision of the papillary muscles has become the excision of choice (15,16,22,23). In selected patients with particularly large redundant mitral valves, anterior leaflet plication may be added to complete separation of the mitral valve and outflow (23,24).


Alcohol septal ablation - introduced by Sigwart in 1994 - is a percutaneous technique that involves injection of alcohol into the first septal perferator of the left anterior descending artery. This is a technique with results similar to the surgical septal myectomy procedure but is less invasive, since it does not involve general anaesthesia and opening of the chest wall and pericardium (which are done in a septal myomectomy). In a select population with symptoms secondary to a high outflow tract gradient, alcohol septal ablation can reduce the symptoms of HCM.6,10,30 The coronary circulation consists of the blood vessels that supply blood to, and remove blood from, the heart muscle itself(rather than chambers). ...


The use of a pacemaker has been advocated in a subset of individuals, in order to cause asynchronous contraction of the left ventricle. Since the pacemaker activates the interventricular septum before the left ventricular free wall, the gradient across the left ventricular outflow tract may decrease. This form of treatment has been shown to provide less relief of symptoms and less of a reduction in the left ventricular outflow tract gradient when compared to surgical myectomy.7 A pacemaker (or artificial pacemaker, so as not to be confused with the hearts natural pacemaker) is a medical device designed to regulate the beating of the heart. ...


In cases that are refractory to all other forms of treatment, cardiac transplantation is an option. An organ transplant is the transplantation of an organ (or part of one) from one body to another, for the purpose of replacing the recipients damaged or failing organ with a working one from the donor. ...


Related disorders

Feline hypertrophic cardiomyopathy is the most common heart disease in cats; the disease process and genetics are believed to be similar to the disease in humans.5
The first feline marker has been discovered32 in 2005. It has been shown to be both heterozygous and homozygous present in about one third (total) of the breed, where a lot of cats seem to be a-sympthomatic. It has also been shown that about half the Maine Coon cats with clinical HCM test negative for this mutation, proving that a second mutation exists in the breed. This mutation has not been found in cats with HCM in other breeds yet. Heart disease is one of a number of different diseases which afflict the heart. ... Trinomial name Felis silvestris catus (Linnaeus, 1758) The cat (or domestic cat, house cat) is a small carnivorous mammal and a subspecies of the wild cat. ... Trinomial name Homo sapiens sapiens Linnaeus, 1758 Humans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin for wise man or knowing man) under the family Hominidae (known as the great apes). ... The Maine Coon is one of the largest breeds of domestic cat, known for its intelligence and playfulness as well as its distinctive physical appearance. ...


References

1. Richardson P, McKenna W, Bristow M, Maisch B, Mautner B, O'Connell J, Olsen E, Thiene G, Goodwin J, Gyarfas I, Martin I, Nordet P. Report of the 1995 World Health Organization/International Society and Federation of Cardiology Task Force on the Definition and Classification of cardiomyopathies. Circulation. 1996 Mar 1;93(5):841-2. (Medline abstract) (Full text)


2. Maron BJ, Thompson PD, Puffer JC, McGrew CA, Strong WB, Douglas PS, Clark LT, Mitten MJ, Crawford MH, Atkins DL, Driscoll DJ, Epstein AE. Cardiovascular preparticipation screening of competitive athletes. A statement for health professionals from the Sudden Death Committee (clinical cardiology) and Congenital Cardiac Defects Committee (cardiovascular disease in the young), American Heart Association. Circulation. 1996 Aug 15;94(4):850-6. (Medline abstract) (Full text)


3. Rivera-Diaz J, Moosvi AR. Apical hypertrophic cardiomyopathy. South Med J. 1996 Jul;89(7):711-3. (Medline abstract), (Full text)


4. Maron BJ, Cecchi F, McKenna WJ. Risk factors and stratification for sudden cardiac death in patients with hypertrophic cardiomyopathy. Br Heart J. 1994 Dec;72(6 Suppl):S13-8. (Medline abstract) and the Task Force on Sudden Cardiac Death of the European Society of Cardiology (http://www.guideline.gov/summary/summary.aspx?doc_id=2977).


5. Kittleson MD, Meurs KM, Munro MJ, Kittleson JA, Liu SK, Pion PD, Towbin JA. Familial hypertrophic cardiomyopathy in maine coon cats: an animal model of human disease. Circulation. 1999 Jun 22;99(24):3172-80. (Medline abstract) Animal model refers to a non-human animal with a disease that is similar to a human condition. ...


6. Brilakis ES, Nishimura RA. Severe pulmonary hypertension in a patient with hypertrophic cardiomyopathy: response to alcohol septal ablation. Heart. 2003 Jul;89(7):790. (Medline abstract)


7. Ommen SR, Nishimura RA, Squires RW, Schaff HV, Danielson GK, Tajik AJ. Comparison of dual-chamber pacing versus septal myectomy for the treatment of patients with hypertropic obstructive cardiomyopathy: a comparison of objective hemodynamic and exercise end points. J Am Coll Cardiol. 1999 Jul;34(1):191-6. (Medline abstract)


8. Doolan G, Nguyen L, Chung J, Ingles J, Semsarian C. Progression of left ventricular hypertrophy and the angiotensin-converting enzyme gene polymorphism in hypertrophic cardiomyopathy. Int J Cardiol. 2004 Aug;96(2):157-63. (Medline abstract)


9. Marian AJ, Yu QT, Workman R, Greve G, Roberts R. Angiotensin-converting enzyme polymorphism in hypertrophic cardiomyopathy and sudden cardiac death. Lancet. 1993 Oct 30;342(8879):1085-6. (Medline abstract)


10. Maron B. Hypertrophic cardiomyopathy: a systematic review. JAMA 2002. 287: 1308-20.


11. Jiang L, Levine RA, King ME, Weyman AE. An integrated mechanism for systolic anterior motion of the mitral valve in hypertrophic cardiomyopathy based on echocardiographic observations. Am Heart J 1987;113:633-44.


12. Sherrid MV, Gunsburg DZ, Moldenhauer S, Pearle G. Systolic anterior motion begins at low left ventricular outflow tract velocity in obstructive hypertrophic cardiomyopathy. J Am Coll Cardiol 2000;36:1344-54.


13. Sherrid MV, Chu Ck, DeLia E, Mogtader A, Dwyer Jr. EM, An echocardiographic study of the fluid mechanics of obstruction in hypertrophic cardiomyopathy. J Am Coll Cardiol 1993;22:816-25.


14. Levine RA, Vlahakes GJ, Lefebvre X, et al. Papillary muscle displacement causes systolic anterior motion of the mitral valve. Circ 1995;91:1189-95.


15. Messmer BJ. Extended myectomy for hypertrophic obstructive cardiomyopathy. Ann Thorac Surg 1994;58:575-7.


16. Schoendube FA, Klues HG, Reith S, Flachskampf FA, Hanrath P, Messmer BJ. Long-term clinical and echocardiographic follow-up after surgical correction of hypertrophic obstructive cardiomyopathy with extended myectomy and reconstruction of the subvalvular mitral apparatus. Circ 1995;92:II-122-7.


17. Klues HG, Maron BJ, Dollar AL, Roberts WC. Diverstiy of structural mitral valve alterations in hypertrophic cardiomyopathy. Circulation 1992;85:1651-60.


18. Henry WL, Clark CE, Griffith JM, Epstein SE. Mechanism of left ventricular outflow obstruction in patients with obstructive asymmetric septal hypertrophy (idiopathic hypertrophic subaortic stenosis). Am J Cardiol 1975;35:337-45.


19. Schwammenthal E, Levine RA. Dynamic subaortic obstruction: a disease of the mitral valve suitable for surgical repair? J Am Coll Cardiol 1996;28:203-6.


20. Roberts CS, McIntosh CL, Brown PS, Cannon RO III, Gertz SD, Clark RE. Reoperation for persistent outflow obstruction in hypertrophic cardiomyopathy. Ann Thorac Surg 1991;51:455-60.


21. Nakatani S, Schwammenthal E, Lever HM, Levine RA, Lytle BW, Thomas JD. New insights into the reduction of mitral valve systolic anterior motion after ventricular septal myectomy in hypertrophic obstructive cardiomyopathy. Am Heart J 1996;131:294-300.


22. Sherrid M, Chaudhry FA, Swistel DG. Obstructive hypertrophic cardiomyopathy. Echocardiography, pathophysiology, and the continuing evolution of surgery for obstruction. Annals of Thoracic Surgery 2003;75:620-32.


23. Balaram SK, Sherrid MV, DeRose JJ, Hillel Z, Winson G, Swistel DG. Beyond extended myectomy for hypertrophic cardiomyopathy: The RPR (Resection-Plication-Release) Repair. Annals of Thoracic Surgery 2005;80: 217-223.


24. McIntosh CL, Maron BJ, Cannon RO, Klues H. Initial results of combined anterior mitral valve plication and ventricular septal myotomy-myectomy for relief of left ventricular outflow obstruction in patients with hypertrophic cardiomyopathy. Circ 1992;86:suppl II:II-60-7.


25. Morrow AF. Hypertrophic subaortic stenosis. Operative methods utilized to relieve left ventricular outflow obstruction. J Thorac Cardiovasc Surg 1978;76: 423-30.


26. Williams WG, Wigle ED, Rakowski H, Smallhorn J, LeBlanc J, Trusler GA. Results of surgery for hypertrophic obstructive cardiomyopathy. Circulation 1987; 76: V104-8.


27. Joyce FS, Lever HM, Cosgrove DM. Treatment of hypertrophic cardiomyopathy by mitral valve repair and septal myectomy. Ann Thorac Surg 1994;57(4):1025-7.


28. Sherrid MV, Barac I, McKenna WJ, Eliott M, Dickie S, Chojnowska L, Casey S, Maron BJ. Multicenter study of the efficacy and safety of disopyramide in obstructive hypertrophic cardiomyopathy. J Am College of Cardiol 2005; 45:1251-58.


29. Wigle D, Sasson Z, Henderson MA, Ruddy TD, Fulop J, Rakowski H, Williams WG. Hypertrophic cardiomyopathy. The importance of the site and the extent of hypertrophy. A review. Progress in Cardiovascular Diseases 1985;28:1-83.


30. Wigle ED, Rakowski H, Kimball BP, Williams WG. Hypertrophic cardiomyopathy - clinical spectrum and treatment. Circulation 1995;92:1680-1692.


31. Maron BJ, McKenna WJ, Danielson GK, Kappenberger LJ, Kuhn HJ, Seidman CE, Shah PM, Spencer WH III, Spirito P, Ten Cate FJ, Wigle ED. American College of Cardiology/European Society of Cardiology clinical expert consensus document on hypertrophic cardiomyopathy. J Am Coll Cardiol. 2003;42:1687-713.


32. Meurs KM, Sanchez X, David RM, Bowles NE, Towbin JA, Reiser PJ, Kittleson JA, Munro MJ, Dryburgh K, Macdonald KA, Kittleson MD., Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus (Medline abstract).


33. Braunwauld E. The Cardiomyopathies, in Braunwald's Heart Disease, 7th ed, D Zipes, et al (eds). Philadelphia, Saunders, 2005.


External links


  Results from FactBites:
 
Hypertrophic Cardiomyopathy | AHealthyMe.com (729 words)
Cardiomyopathy is an ongoing disease process that damages the muscle wall of the lower chambers of the heart.
Hypertrophic cardiomyopathy is a form of cardiomyopathy in which the walls of the heart's chambers thicken abnormally.
Hypertrophic cardiomyopathy is the result of abnormal growth of the heart muscle cells.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m