Antiarrhythmic effect of carvedilol after acute myocardial infarction: results of the Carvedilol Post-Infarct Survival Control in Left Ventricular Dysfunction (CAPRICORN) trial.
OBJECTIVE
Whether beta-blockers reduce atrial arrhythmias and, when added to an angiotensin-converting enzyme (ACE) inhibitor, ventricular arrhythmia is unknown.


BACKGROUND
Ventricular and atrial arrhythmias are common after acute myocardial infarction (AMI) and are associated with a poor prognosis. Angiotensin-converting enzyme inhibitors reduce the incidence of both types of arrhythmia.


METHODS
The antiarrhythmic effect of carvedilol was examined in a placebo-controlled multicenter trial, the Carvedilol Post-Infarct Survival Control in Left Ventricular Dysfunction (CAPRICORN) study, which enrolled 1,959 patients with reduced left ventricular systolic function after AMI, 98% of whom were treated with an ACE inhibitor.


RESULTS
The incidence of atrial fibrillation/flutter was 53 to 984 (5.4%) in the placebo group and 22 to 975 (2.3%) in the carvedilol group, giving a carvedilol/placebo hazard ratio (HR) of 0.41 (95% confidence interval [CI] 0.25 to 0.68; p = 0.0003). The corresponding rates of ventricular tachycardia/flutter/fibrillation were 38 to 984 (3.9%) and 9 to 975 (0.9%) (HR 0.24, 95% CI 0.11 to 0.49; p < 0.0001).


CONCLUSIONS
Carvedilol has a powerful antiarrhythmic effect after AMI, even in patients already treated with an ACE inhibitor. Carvedilol suppresses atrial as well as ventricular arrhythmias in these patients.
McMurray
John
J
Department of Cardiology, Western Infirmary, Glasgow, United Kingdom. j.mcmurray@bio.gla.ac.uk <j.mcmurray@bio.gla.ac.uk>
Køber
Lars
L
Robertson
Michele
M
Dargie
Henry
H
Colucci
Wilson
W
Lopez-Sendon
Jose
J
Remme
Willem
W
Sharpe
D Norman
DN
Ford
Ian
I
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000517:prevention & control*; D002227:Carbazoles / Q000627:therapeutic use*; D000077261:Carvedilol; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications*; D011412:Propanolamines / Q000627:therapeutic use*; D011446:Prospective Studies
D000319:Adrenergic beta-Antagonists; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol