Current concepts in clinical therapeutics: congestive heart failure

The epidemiology and etiology, pathophysiology, diagnosis, and treatment of congestive heart failure (CHF) are reviewed. CHF affects as many as 4 million Americans and is one of the most prevalent causes of death in hospitalized patients. Major risk factors for developing CHF include advanced age, male sex, hypertension, coronary artery disease, smoking, hypercholesterolemia, diabetes mellitus, and rheumatic heart disease. Heart failure results from decreased intrinsic myocardial contractility caused by one or more of three changes: (1) altered adrenergic nervous system function, (2) impaired delivery of calcium to contractile elements in the heart, and (3) reduced myosin-ATPase activity in the myocardium. The disease is progressive, and no intervention has yet been found to stop it effectively. CHF is diagnosed based on subjective signs and symptoms and objective assessment using auscultation, ECG, chest roentgenogram, laboratory tests, and noninvasive and invasive tests. Treatment of CHF begins with restriction of physical activity and sodium intake. Pharmacologic interventions start with either digitalis glycosides or thiazide diuretics; both may be used concomitantly as the disease progresses. Current studies are focusing on the use of angiotensin-converting enzyme inhibitors as first-line agents for CHF. When CHF worsens, loop diuretics are substituted for or added to the thiazide diuretics, and vasodilators are added to reduce the workload on the heart. Other inotropic agents, including the new bipyridine derivatives, may also be used. In patients not responding to these and other aggressive therapeutic interventions, cardiac transplantation is the only option. Despite advances in management of CHF, little improvement in overall survival has been demonstrated, and no intervention has stopped or reversed the progression of CHF.