Calcium antagonists and sympathetic activity in congestive heart failure

Objective To review the sympathetic abnormalities occurring in heart failur e, their pathophysiological importance and clinical relevance, and the effe cts of drug treatment, with particular reference to calcium antagonists. Sympathetic activation in heart failure Indirect and direct approaches to s tudy sympathetic function in humans have documented conclusively that sympa thetic activation represents a hallmark of cardiac failure syndrome. Eviden ce indicates that sympathetic overactivity is associated with, and probably caused by, a baroreflex impairment and that it has adverse effects on pati ents' prognosis and survival. Goals of drug treatment in congestive heart failure In the past, drug treat ment in heart failure was aimed at improving patients' survival by ameliora ting cardiac hemodynamics, It is now established that a major goal of thera peutic intervention is also to reduce sympathetic activation characterizing heart failure. Calcium antagonists in heart failure Studies with short-acting calcium anta gonists show that they enhance sympathetic activation and that this has an adverse effect on patients' survival. In contrast, third generation calcium antagonists such as amlodipine, which have a slow onset and long duration of action, do not adversely affect sympathetic function and reflex cardiova scular control. Indeed, evidence suggests calcium antagonists with this pro file may exert favorable clinical effects. (C) 1998 Lippincott Williams & W ilkins.