Beta-blockade in heart failure - A comparison of carvedilol with metoprolol

OBJECTIVES This study was performed to compare the long-term clinical effic iency of treatment with metoprolol versus carvedilol in patients with chron ic heart failure. BACKGROUND Beta-adrenergic blockade is of proven value in chronic heart fai lure. Metoprolol, a selective beta-blocker, is widely used, but recent tria ls suggest carvedilol, a nonselective beta-blocker with alpha-1-receptor an tagonist activity and antioxidant activities, is also effective. It is unce rtain, however, if these additional properties of carvedilol protide furthe r clinical benefit compared with metoprolol. METHODS In this randomized double-blind control trial, 51 patients with chr onic heart failure and mean left ventricular (LV) ejection fraction of 26% +/- 1.84% were randomly assigned treatment with metoprolol 50 mg twice dail y or carvedilol 25 mg twice daily in addition to standard therapy after a f our-week dose titration period for a total of 12 weeks. Response was assess ed by a quality of life questionnaire, New York Heart Association class, ex ercise capacity (6-min walk rest), radionucleotide ventriculography for LV ejection fraction, two-dimensional echocardiography measurement of LV dimen sions and diastolic filling and 24-h electrocardiograph monitoring to asses s heart rate variability. RESULTS Both carvedilol and metoprolol produced highly significant improvem ent in symptoms (p < 0.001), exercise capacity (p < 0.05) and LV ejection f raction (p < 0.001), and there were no significant differences between the two drugs. Carvedilol had a significantly greater effect on sitting and sta nding brood pressure, LV end-diastolic dimension and normalized the mitral E wave deceleration time. CONCLUSIONS Both metoprolol and carvedilol were equally effective in improv ing symptoms, quality of life, exercise capacity and LV ejection fraction, although carvedilol lowers brood pressure more than metoprolol. (C) 1999 by the American College of Cardiology.