Pharmacologic treatment of congestive heart failure

Abstract

Congestive heart failure is a clinical syndrome producing symptomatic deterioration, functional impairment, and shortened life span. The syndrome is complex in that it includes both peripheral and cardiac effects which contribute to the progression of heart failure. In the periphery, elevations in the sympathetic nervous system and renin-angiotensin system increase afterload and contribute to further salt and water retention. The central cardiac abnormalities include remodeling of the heart and downregulation of beta receptors. Traditional heart failure therapy has included treatment of fluid retention with diuretics, although their effect on mortality has never been addressed. The most proven therapy in heart failure is treatment with vasodilators, particularly angiotensin-converting enzyme (ACE) inhibitors. Improved survival with ACE-inhibitor therapy has been demonstrated in patients with severe heart failure (CONSENSUS), mild to moderate heart failure (SOLVD), and in comparison with vasodilator therapy with hydralazine isosorbide dinitrate (VHeFT II). Improved survival has also been noted in postmyocardial infarction when the ejection fraction is decreased (SAVE). The ACE inhibitors have now become standard therapy for heart failure regardless of severity. Additive vasodilator therapy with calcium-channel antagonists is under investigation. Inotropic therapy is controversial at present because of disappointing mortality results. The clinical mainstay digitalis remains without convincing mortality reduction data. Other inotropic agents, particularly phosphodiesterase inhibitors, have shown uniformly negative survival results. However, the new mixed action agents vesnarinone and pimobenden have shown favorable data, with vesnarinone demonstrating a mortality reduction effect. Beta-blocker therapy in heart failure has also found renewed interest, particularly with the new agents carvedolol and bucindolol which also have vasodilating properties.