Mortality benefit with remote ischemic preconditioning in STEMI: a frequentist and Bayesian meta-analysis of randomized controlled trials

Abstract

Abstract Introduction Myocardial infarction related morbidity and mortality remains substantial despite perpetual improvement in patient care. Remote ischemic preconditioning among patients with myocardial infarction has exhibited to improve surrogate markers of ischemia. However, its effect on all-cause mortality is not well established. Purpose An updated frequentist and Bayesian meta-analysis of randomised control trials [RCTs] investigating remote ischemic preconditioning among patients with ST segment elevation myocardial infarction [STEMI] and its effect on all-cause mortality. Methods A systematic search across PubMed, EMBASE and Cochrane databases was performed. The inclusion criteria was RCTs comparing remote ischemic preconditioning with standard treatment juxtaposed to standard treatment alone among patients with STEMI and reporting all-cause mortality. Data extraction was carried out by two independent authors and looked for reproducibility. Inverse variance method with Paule-Mandel estimator for tau2 and Hartung-Knapp adjustment was used to calculate Risk Ratio with 95% confidence interval. Heterogeneity was assessed using I2 statistics. We estimated the robustness of our pooled effect size using Bayesian meta-analysis. A weakly informative prior [normal (0, 1) for intercept and uniform (0, 2) for standard deviation] and 20000 iterations [10000 warm-up + 10000 sampling] were used for Bayesian meta-analysis. We used meta ( ) and brm ( ) package in R for frequentist and Bayesian meta-analysis, respectively. All statistical analysis was carried out using R statistical software version 3.6.2. The certainty of evidence was assessed using Grading of Recommendations, Assessment, Development and Evaluations (GRADE). Results Five RCTs comprising a total of 6043 patients [3010 intervention and 3033 controls] were included in the final analysis. The largest included RCT was the CONDI-2/ERIC-PPCI 2019 trial. Remote ischemic preconditioning among patients with STEMI had no effect on all-cause mortality at follow-up [RR=0.70, 95% confidence interval = 0.26–1.87, I2=60%] [Figure 1, Panel A]. Similar results were obtained from hierarchical Bayesian meta-analysis [RR=0.55, 95% credibility interval = 0.23–1.38] [Figure 1, Panel B]. Low certainty of evidence as per GARDE, reports no benefit of remote ischemic preconditioning in reducing the risk of all-cause mortality in STEMI. Conclusion Remote ischemic preconditioning among patients with STEMI has no effect on all-cause mortality at follow-up. Figure 1 Funding Acknowledgement Type of funding source: None