Q Are angiotensin-receptor blockers (ARBs) equivalent to or better than angiotensin-converting enzyme (ACE) inhibitors in the treatment of heart failure?
A Juanita Reigle, RN, MSN, ACNP, replies:
ACE inhibitors reduce mortality and morbidity in patients with chronic heart failure and left ventricular systolic dysfunction.1,2 The evidence is so compelling that for patients with left ventricular systolic dysfunction, the prescription of an ACE inhibitor at hospital discharge is used by various regulatory agencies as a quality indicator.
The mechanism of these benefits is likely due to the inhibition of angiotensin II production and a decrease in the breakdown of bradykinin. Angiotensin II is a potent vasoconstrictor that has deleterious effects on the failing heart by increasing oxidative demands, promoting cell growth, stimulating vascular and left ventricular remodeling, and triggering proteinuria.3 Bradykinin stimulates the release of nitric oxide and prostacyclin, both potent vasodilators that may account for the beneficial...