RESUMO
BACKGROUND: It is controversial as to whether nicorandil would have cardioprotective effects in patients with acute myocardial infarction (AMI) who are undergoing reperfusion therapy. A meta-analysis was performed to study the impacts of nicorandil on functional outcomes after AMI. METHODS AND RESULTS: Randomized prospective cohort or retrospective cohort publications were identified up to October 2007 by means of a computer search of MEDLINE and Google Scholar databases. Two reviewers checked the quality of the studies and extracted data regarding patient and disease characteristics, study design, functional parameters such as Thrombolysis In Myocardial Infarction (TIMI) flow grade after reperfusion, left ventricular ejection fraction (LVEF) and left ventricular end-diastolic volume index (LVEDVI). Seventeen studies were included for the meta-analysis in this study. Nicorandil treatment reduced the incidence of TIMI flow grade < or =2 in 1,337 patients of 10 studies (risk ratio 0.63; 95% confidence interval (CI) 0.44 to 0.91). While no beneficial effect was observed on the peak creatine kinase value, nicorandil treatment was associated with greater LVEF (by 3.7%, 95%CI 1.8 to 5.7%), and lower LVEDVI (by 8.8 ml/kg, -14.4 to -3.3 ml/kg) in 905 patients of 11 studies. CONCLUSIONS: The meta-analysis demonstrated that nicorandil treatment adjunctive to reperfusion therapy has beneficial effects on microvascular function and on functional recovery after AMI.