Clinical investigationEffects of metoprolol and carvedilol on cause-specific mortality and morbidity in patients with chronic heart failure—COMET
Section snippets
Methods
The COMET was a randomized, double-blind, parallel group trial comparing carvedilol with metoprolol for the treatment of chronic heart failure. Details of the study design have been published previously.14., 15. A total of 3029 patients with chronic heart failure was randomized in 316 centers in 15 European countries. Patients were recruited between December 1996 and January 1999. Follow-up was concluded in November 2002.
An end point committee classified all fatal events and cases of acute
Results
A total of 3029 patients was randomized, 1511 and 1518 to carvedilol and metoprolol, respectively. The 2 study groups were well matched (see Table I). The mean study duration was 58 ± 6 months (time from randomization to study closure). The profile of the study is shown in Figure 1 and the baseline characteristics are shown in Table I. The mean decrease in systolic blood pressure after 4 months in patients undergoing treatment was 3.8 mm Hg in the carvedilol group and 2.0 mm Hg in the
Discussion
The COMET study demonstrates that treatment of patients with chronic heart failure with carvedilol compared with metoprolol tartrate improves survival. Cardiovascular death was particularly reduced. Modes of cardiovascular death, sudden death, death caused by circulatory failure, and death caused by stroke were all reduced by carvedilol as compared with metoprolol. There was also a significant reduction in the risk of fatal or nonfatal myocardial infarctions by carvedilol.
Mode of death was
References (27)
- et al.
Prolongation of survival in congestive cardiomyopathy by beta-receptor blockade
Lancet
(1979) - et al.
Beneficial effects of metoprolol in idiopathic dilated cardiomyopathy. Metoprolol in Dilated Cardiomyopathy (MDC) Trial Study Group
Lancet
(1993) - et al.
Comparison of carvedilol and metoprolol on clinical outcomes in patients with chronic heart failure in the Carvedilol Or Metoprolol European Trial (COMET): randomised controlled trial
Lancet
(2003) - et al.
Carvedilol improves endothelium-dependent dilatation in patients with coronary artery disease
Am. Heart J.
(2000) - et al.
Cardiovascular protection and blood pressure reduction: a meta-analysis
Lancet
(2001) - et al.
Bisoprolol for the treatment of chronic heart failure: a meta-analysis on individual data of two placebo-controlled studies–CIBIS and CIBIS II. Cardiac Insufficiency Bisoprolol Study
Am. Heart J.
(2002) Do beta-blockers prolong survival in heart failure only by inhibiting the beta1-receptor? A perspective on the results of the COMET trial
J. Card. Fail.
(2003)- et al.
COMET: a proposed mechanism of action to explain the results and concerns about dose
Lancet
(2003) - et al.
Effect of chronic beta-adrenergic receptor blockade in congestive cardiomyopathy
Br. Heart J.
(1975) A randomized trial of beta-blockade in heart failure. The Cardiac Insufficiency Bisoprolol Study (CIBIS). CIBIS Investigators and Committees
Circulation
(1994)