Evolving role of calcium channel blockers in heart failure.

Abstract

Calcium channel blockers are theoretically effective in the treatment of chronic systolic heart failure because of their actions as arteriolar dilators, antiischemic agents, and relaxants of diastolic left ventricular function, and because they may prevent progression of myocardial dysfunction. The first-generation calcium channel blockers nifedipine, verapamil, and diltiazem cause hemodynamic and clinical deterioration and may increase the frequency of cardiac events in postmyocardial infarction patients with heart failure. These drugs depress left ventricular contractility in the short term, and can activate neurohormonal systems due to their hypotensive effects. The second-generation calcium channel blocker felodipine does not activate the sympathetic nervous and renin-angiotensin systems, but has no effect on exercise capacity or mortality. Amlodipine increases exercise time and reduces symptoms and plasma norepinephrine concentration in heart failure. It also reduces morbidity and mortality in New York Heart Association class i.v. patients with nonischemic dilated cardiomyopathy, and appears to be effective as primary therapy for patients with dilated cardiomyopathy.