Oxygen Therapy in Patients with Acute Myocardial Infarction: A Systemic Review and Meta-Analysis

Objective: Oxygen therapy is frequently used for patients with acute myocardial infarction. The aim of this study is to perform a systematic review and meta-analysis to compare the outcomes of oxygen therapy versus no oxygen therapy in post–acute myocardial infarction settings. Methods: A systematic search of electronic databases was conducted for randomized studies, which reported cardiovascular events in oxygen versus no oxygen therapy. The evaluated outcomes were all-cause mortality, recurrent coronary events (ischemia or myocardial infarction), heart failure, and arrhythmias. Summary-adjusted risk ratios (RRs) were calculated by the random effects DerSimonian and Laird model. The risk of bias of the included studies was assessed by Cochrane scale. Results: Our meta-analysis included a total of 7 studies with 3842 patients who received oxygen therapy and 3860 patients without oxygen therapy. Oxygen therapy did not decrease the risk of all-cause mortality (pooled RR, 0.99; 95% confidence interval [CI], 0.81-1.21; P =.43), recurrent ischemia or myocardial infarction (pooled RR, 1.19; 95% CI, 0.95-1.48; P =.75), heart failure (pooled RR, 0.94; 95% CI, 0.61-1.45; P =.348), and occurrence of arrhythmia events (pooled RR, 1.01; 95% CI, 0.85-1.2; P =.233) compared with the no oxygen arm. Conclusions: This meta-analysis confirms the lack of benefit of routine oxygen therapy in patients with acute myocardial infarction with normal oxygen saturation levels.