Meta-analysis of antiarrhythmic drug trials

During the past 15 years, the efficacy of antiarrhythmic drugs has been inv estigated for reducing premature death in patients at high risk of arrhythm ia. Whereas the benefits of beta-blocker therapy are well established, a re duction in mortality with other antiarrhythmic drugs remains unproved and i n some cases, there is evidence of increased mortality with class I and som e class III agents. A limitation of individual clinical trials is inadequat e sample size to detect significant differences between interventions. Meta -analysis, by combining results from multiple clinical trials, provides a t echnique to overcome sample size limitations and assess the benefits and li mitations of an intervention. Thirteen randomized clinical trials evaluated the role of prophylactic amiodarone in patients at risk of death from card iac arrhythmias. Whereas 3 of these studies reported a reduction in mortali ty, several others revealed no benefits of amiodarone, Because neither tria l was designed to detect reductions in total mortality, it remained unclear whether the beneficial effect of amiodarone on arrhythmic death and resusc itated ventricular fibrillation translated into a beneficial effect on tota l mortality, To address this, a meta-analysis was performed from the 13 tri als of amiodarone in patients after an acute myocardial infarction or with congestive heart failure. The results showed a significant reduction in mor tality and in arrhythmic death with amiodarone, (C)1999 by Excerpta Medica, Inc.