Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hypertrophic cardiomyopathy is characterized by abnormalities of the myocardium, and the activation and conduction tissues, that may have separate manifestations, but often occur together in complex clinical pictures. The subaortic gradient, although not always present, is the most classical manifestation of the disease, with its typical dynamic behavior, changing with preload, afterload and contractility. In most cases it is due to systolic motion of the mitral valve against the septum in systole, but in a few it is caused by midventricular "constriction". Alteration of diastolic ventricular function is important, and probably the main cause of heart failure, that is usually accompanied by normal systolic function. Mitral insufficiency is common in the obstructive forms, due to the abnormal mitral valve motion, but in some cases it may be due to structural abnormalities of the valve. There may be systolic constriction, or nonatherosclerotic occlusion of the intramyocardial coronary arteries, causing myocardial infarction and ventricular aneurysms, that may lead to systolic dysfunction. The electrocardiogram is rarely normal. Hypertrophy patterns, deeply inverted T waves, deep Q waves, QRS slurring suggestive of WPW syndrome without true preexcitation are the most common manifestations. Rhythm disturbances are common and include sinus node dysfunction, superconductor atrioventricular node or heart block. Atrial fibrillation is frequent and may have catastrophic consequences, including systemic embolism. Non-sustained ventricular arrhythmias are often present, but its predictive value for sudden death is unclear. Monomorphic ventricular tachycardia is infrequent, and programmed stimulation is more likely to precipitate polymorphic ventricular tachycardia of difficult clinical interpretation. Sudden death may be due to multiple mechanisms, and it is difficult to predict and prevent.
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PMID:[Hemodynamic and electrophysiologic changes in hypertrophic cardiomyopathy]. 868 13

Results of recent clinical trials allow an evidence-based approach to ventricular arrhythmias (VAs). The implantable cardioverter-defibrillator (ICD) has clearly established its role in the secondary prevention of VA and should be considered first-line therapy in patients surviving episodes of potentially lethal VAs. It has also been clearly shown that in these patients, antiarrhythmic drug selection by means of serial Holter recording or electrophysiologic study does not improve survival. Antiarrhythmic drug therapy (including amiodarone) as primary prevention in high-risk patients (eg, those who have experienced a myocardial infarction or who have heart failure) has thus far not reduced the mortality rate. In contrast, use of the ICD as a primary preventative strategy has reduced the mortality rate in patients after myocardial infarction who have reduced left ventricular function, nonsustained ventricular tachycardia, and inducible ventricular tachycardia during electrophysiologic study. Thus, patients fitting this clinical profile are best served by implantation of an ICD. Monomorphic ventricular tachycardia occurs rarely in patients without heart disease. These arrhythmias are best treated with catheter ablation therapy, a treatment with a high rate of success and a low rate of complications.
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PMID:Ventricular Arrhythmias. 1109 37