Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cardiomyopathies are defined as 'heart muscle diseases of unknown cause' and classified into hypertrophic, dilated and restrictive types, respectively. Hypertrophic cardiomyopathy is notable for massive ventricular hypertrophy without obvious cause, impaired diastolic and systolic function, a tendency for sudden death and a familial propensity. Dilated cardiomyopathy by contrast, demonstrates severe systolic failure progressing to congestive heart failure, with usually no familial tendency. Restrictive cardiomyopathy and diastolic heart disease represent syndromes with restriction to ventricular filling due to restrictive forces in the endomyocardium (and in constrictive pericarditis in the pericardium). The commonest cause of restrictive cardiomyopathy is endomyocardial fibrosis now usually known as hypereosinophilic endomyocardial disease. Specific heart muscle diseases are those conditions in which myocardial disease is due to a known cause: they usually produce systolic failure though occasionally a restrictive syndrome is evident. Amyloid heart disease occupies a place intermediate between cardiomyopathies and specific heart muscle diseases. The major features of the above conditions are described and current and future advances noted. Examples are the identification of the gene probably responsible for hypertrophic cardiomyopathy located on chromosome 14, and the identification of virus RNA particles in the myocardium in both myocarditis and in dilated cardiomyopathy, which strengthens the growing evidence suggesting that some cases of dilated cardiomyopathy may be due to previous myocarditis.
 ...
PMID:Cardiomyopathies and specific heart muscle diseases. Definitions, terminology, classifications and new and old approaches. 140 13

Cardiomyopathies are an important cause of congestive heart failure in the elderly, and the magnitude of the problem is compounded by changing population demographics and the frequency of congestive heart failure in the elderly. Although the data are far from complete, differences in the clinical presentations and natural history of the cardiomyopathies in older and younger patients are becoming more clearly appreciated. Dilated cardiomyopathy (DCM) is clearly more common than previously appreciated, and elderly patients have a worse prognosis than their younger counterparts with this disease. The medical management of DCM is often more difficult in the elderly, and the problem is compounded by the relatively infrequent use of cardiac transplantation as a therapeutic option. Hypertrophic cardiomyopathy is also more common than previously appreciated, and changes in left ventricular structure often create difficulties in differentiating pathologic states from physiologic. Fortunately, the prognosis for HOCM is more favorable in the elderly than in younger patients and may be partly accounted for by the different structure of the left ventricle. If needed, surgery is an option for elderly patients with medically refractory HOCM, but particular attention must be paid to the presence and severity of associated cardiovascular disease. Restrictive cardiomyopathy with diastolic dysfunction is increasingly recognized as a cause of congestive heart failure. The differentiation from systolic dysfunction is crucial, because the treatments are so markedly different. Age-related changes in diastolic function are becoming more apparent and better characterized, but standardization of age-related "normal" values is still not available. The diagnosis of restrictive heart disease should stimulate a search for an underlying cause, inasmuch as restrictive cardiomyopathy remains a diagnosis of exclusion. Advances in noninvasive imaging have led to a resurgence of interest and have enhanced our knowledge of the cardiomyopathies. Further investigation should proceed in conjunction with studies aimed at defining the characteristics and variables of "normal" aging. For the present, the enigmatic, poorly identified "cardiomyopathies" remain a problem for both young and old.
 ...
PMID:Cardiomyopathies in the elderly. 158 13

Hypertrophic cardiomyopathy is a disease characterised by massive ventricular hypertrophy, reduced diastolic function and excessive ventricular contraction. It involves sections of both ventricles, but in particular the left ventricle. Although it was initially thought that this pathology might depend on a modified systolic function, it is now widely held that the main alteration is of a diastolic type. The paper focuses on the importance of the genetic component in this cardiopathy, and stresses that the majority of patients affected by this disease and examined by the Authors had positive family histories, in line with previously published reports. In the majority of cases the pathology is transmitted in a dominant autosomic manner, although there are also sporadic episodes of non-hereditary transmission due to genetic mutation.
 ...
PMID:[Importance of the genetic aspect in hypertrophic cardiomyopathy]. 209 30

Cardiomyopathies in the elderly have certain characteristic features. The dilated form appears to be less common than in younger patients. Hypertrophic cardiomyopathy is more often associated with severe and concentric hypertrophy. The prognosis of hypertrophic cardiomyopathy seems to be better in the elderly, because they appear to have a lower incidence of sudden death. Restrictive cardiomyopathies are not common in the elderly, and senile amyloid heart disease rarely, if ever, results in congestive heart failure. A syndrome of clinical heart failure with reduced diastolic compliance and preserved systolic function is more common in elderly patients.
 ...
PMID:Cardiomyopathies in the elderly. 329 76

Cardiovascular diseases responsible for sudden unexpected death in highly conditioned athletes are largely related to the age of the patient. In most young competitive athletes (less than 35 years of age) sudden death is due to congenital cardiovascular disease. Hypertrophic cardiomyopathy appears to be the most common cause of such deaths, accounting for about half of the sudden deaths in young athletes. Other cardiovascular abnormalities that appear to be less frequent but important causes of sudden death in young athletes include congenital coronary artery anomalies, ruptured aorta (due to cystic medial necrosis), idiopathic left ventricular hypertrophy and coronary artery atherosclerosis. Diseases that appear to be very uncommon causes of sudden death include myocarditis, mitral valve prolapse, aortic valve stenosis and sarcoidosis. Cardiovascular disease in young athletes is usually unsuspected during life, and most athletes who die suddenly have experienced no cardiac symptoms. In only about 25% of those competitive athletes who die suddenly is underlying cardiovascular disease detected or suspected before participation and rarely is the correct clinical diagnosis made. In contrast, in older athletes (greater than or equal to 35 years of age) sudden death is usually due to coronary artery disease, and rarely results from congenital heart disease.
 ...
PMID:Causes of sudden death in competitive athletes. 351 Feb 33

Hypertrophic cardiomyopathy is a primary myocardial disease in which symptoms may frequently result from impaired left ventricular relaxation, filling and compliance. In the present investigation, Doppler echocardiography was utilized to measure transmitral flow velocity and thereby assess left ventricular diastolic performance noninvasively in a group of 111 patients representative of the broad clinical spectrum of hypertrophic cardiomyopathy. In patients with hypertrophic cardiomyopathy, all Doppler indexes of diastolic relaxation and filling differed significantly (p less than 0.001) from those obtained in 86 control subjects without heart disease, namely, prolongation of isovolumic relaxation (94 +/- 24 versus 78 +/- 12 ms) and of the early diastolic peak of flow velocity (244 +/- 55 versus 220 +/- 28 ms), as well as slower deceleration (3.4 +/- 1.4 versus 4.9 +/- 1.3 m/s2) and reduced maximal flow velocity in early diastole (0.5 +/- 0.2 versus 0.6 +/- 0.1 m/s). As an apparent compensation for impaired relaxation and early diastolic filling, the atrial contribution to left ventricular filling was increased, as shown by increased late diastolic flow velocity (0.4 +/- 0.3 versus 0.3 +/- 0.1 m/s) and reduced ratio of maximal flow velocity in early diastole to that in late diastole (1.4 +/- 0.8 versus 2.1 +/- 0.9). The vast majority of patients with hypertrophic cardiomyopathy (91 [82%] of 111) showed evidence of impaired left ventricular diastolic performance, as assessed from the Doppler waveform. Abnormal Doppler diastolic indexes were identified with similar frequency in patients with (78%) or without (83%) left ventricular outflow obstruction, as well as in patients with (84%) or without (80%) cardiac symptoms. However, patients with nonobstructive hypertrophic cardiomyopathy showed more severe alterations in the Doppler indexes of diastolic function than did patients with obstruction. Thus, abnormal diastolic performance as assessed by Doppler echocardiography was apparent in the vast majority of the study patients with hypertrophic cardiomyopathy, independent of the presence or absence of cardiac symptoms or a subaortic pressure gradient. The high frequency with which diastolic abnormalities are identified in asymptomatic patients with hypertrophic cardiomyopathy suggests that impaired diastolic performance may be present at a time in the natural history of the disease when functional limitation is not yet evident.
 ...
PMID:Noninvasive assessment of left ventricular diastolic function by pulsed Doppler echocardiography in patients with hypertrophic cardiomyopathy. 365 41

Hypertrophic cardiomyopathy is a cardiac disorder of unknown aetiology which is characterised by hypertrophy of a non-dilated left ventricle. The course of hypertrophic cardiomyopathy may be relatively benign, but the risk of sudden death due to ventricular arrhythmias is an important clinical problem. Those patients at greatest risk of sudden death appear to be those with the combination of diagnosis in childhood, a family history of hypertrophic cardiomyopathy and sudden death, and syncopal episodes. The treatment of hypertrophic cardiomyopathy-associated ventricular tachycardia with 'conventional' antiarrhythmic agents (disopyramide, quinidine, mexiletine) has seldom been successful. However, treatment of this arrhythmia with amiodarone in well-matched but non-parallel groups of patients has resulted in suppression of arrhythmia and improved survival compared with that seen with 'conventional' antiarrhythmic agents.
 ...
PMID:Does treatment influence the natural history of patients with hypertrophic cardiomyopathy? 403 53

A thorough cardiovascular evaluation is necessary to detect potentially lethal abnormalities that may predispose children and adolescents to sports-related sudden death. Hypertrophic cardiomyopathy and anomalous origin of the left coronary artery from the right sinus of Valsalva are the two most common cardiac abnormalities associated with sudden death during childhood. Other conditions potentially associated with sudden death are Marfan's syndrome, aortic valve stenosis, primary pulmonary hypertension, and arrhythmias. A detailed medical evaluation is indicated for subjects who have a history of nonvasodepressor syncope, exercise-related syncope or presyncope, angina pectoris, or known congenital or acquired heart disease. In addition, a family history of premature sudden unexpected syncope or death, hypertrophic cardiomyopathy, premature atherosclerotic heart disease, severe arrhythmias, or Marfan's syndrome or premature aortic aneurysms is an indication for a thorough cardiovascular evaluation before participation in sports.
 ...
PMID:Cardiovascular evaluation of the child and adolescent before participation in sports. 406 61

Hypertrophic cardiomyopathy (HCM), a primary heart disease, in most of the cases genetically transmitted, characterized by hypertrophy, often asymmetric, of the left ventricle (LV), presents certain peculiarities in old agers. The shape of the LV in old agers, is characterized by aorto-septal angulation, by the frequent presence of a septal bulge and the calcification of the posterior mitral ring which contributes to the narrowing of the LV ejection tract by the anterior displacement of the mitral valve. Thus, HCM in old agers can also have an acquired component associated with the mild changes of aging, which in certain conditions can lead to the appearance of some peculiar forms of disease.
 ...
PMID:Hypertrophic cardiomyopathy in old agers. Definitions and general considerations. 864 84

Hypertrophic cardiomyopathy is a human heart disease characterized by increased ventricular mass, focal areas of fibrosis, myocyte, and myofibrillar disorganization. This genetically dominant disease can be caused by mutations in any one of several contractile proteins, including beta cardiac myosin heavy chain (beta MHC). To determine whether point mutations in human beta MHC have direct effects on interfering with filament assembly and sarcomeric structure, full-length wild-type and mutant human beta MHC cDNAs were cloned and expressed in primary cultures of neonatal rat ventricular cardiomyocytes (NRC) under conditions that promote myofibrillogenesis. A lysine to arginine change at amino acid 184 in the consensus ATP binding sequence of human beta MHC resulted in abnormal subcellular localization and disrupted both thick and thin filament structure in transfected NRC. Diffuse beta MHC K184R protein appeared to colocalize with actin throughout the myocyte, suggesting a tight interaction of these two proteins. Human beta MHC with S472V mutation assembled normally into thick filaments and did not affect sarcomeric structure. Two mutant myosins previously described as causing human hypertrophic cardiomyopathy, R249Q and R403Q, were competent to assemble into thick filaments producing myofibrils with well defined I bands, A bands, and H zones. Coexpression and detection of wild-type beta MHC and either R249Q or R403Q proteins in the same myocyte showed these proteins are equally able to assemble into the sarcomere and provided no discernible differences in subcellular localization. Thus, human beta MHC R249Q and R403Q mutant proteins were readily incorporated into NRC sarcomeres and did not disrupt myofilament formation. This study indicates that the phenotype of myofibrillar disarray seen in HCM patients which harbor either of these two mutations may not be directly due to the failure of the mutant myosin heavy chain protein to assemble and form normal sarcomeres, but may rather be a secondary effect possibly resulting from the chronic stress of decreased beta MHC function.
 ...
PMID:Point mutations in human beta cardiac myosin heavy chain have differential effects on sarcomeric structure and assembly: an ATP binding site change disrupts both thick and thin filaments, whereas hypertrophic cardiomyopathy mutations display normal assembly. 910 42


1 2 3 4 5 6 7 8 9 10 Next >>