The effect of milrinone on mortality in adult patients underwent CABG surgery: A systematic review of randomized clinical trials with meta-analysis and trial sequential analysis

Abstract Background: As an inodilator, milrinone is commonly used for patients underwent coronary artery bypass graft surgery (CABG) because of its effectiveness in decreasing cardiac index and mitral regurgitation. This study was to perform a systematic meta-analysis of existing studies in the past 20 years to evaluate the impact of milrinone on mortality in patients underwent CABG surgery. Methods: We performed a systematic literature search on the application of milrinone in patients underwent CABG surgery, which published between 1997 and 2017 in BioMed Central, PubMed, EMBASE, and the Cochrane Central Register. The included literatures should be set as milrinone compared to a group receiving either placebo or standard treatment, and further compare to systemic administration. Results: The network meta-analysis included 723 patients from 16 randomized clinical trials. Overall, there was no significant difference in mortality between the milrinone group and the placebo/standard care group when patients underwent CABG surgery. Besides that, 9 trials (with 440 randomized patients), 4 trials (with 212 randomized patients), and 10 trials (with 470 randomized patients) reported that the occurrence of myocardial infarction (MI), myocardial ischemia, and arrhythmias in the milrinone group were decreased comparing with the placebo/standard care group, respectively. Between the milrinone treatment and placebo/standard care groups, the occurrence of myocardial infarction, myocardial ischemia, arrhythmias was all significantly different. However, the occurrence of stroke and renal failure, duration of inotropic support (h), need for intra-aortic balloon pump (IABP), and mechanical ventilation (h) between these two groups showed no differences. Conclusions: Based on the current results, milrinone might be unable to decrease the mortality in adult CABG surgical patients, but can significantly ameliorate the occurrence of MI, myocardial ischemia, and arrhythmias compared with placebo-treated patients. These results provide evidence for further clinical application of milrinone and therapy strategies for CABG surgery. However, along with milrinone application in clinical use, sufficient randomized clinical trials need to be collected, and the potential benefit and adverse effects should be analyzed and reevaluated.