Safety and efficacy of mechanical circulatory support with Impella or intra-aortic balloon pump for high-risk percutaneous coronary intervention and/or cardiogenic shock: Insights from a network meta-analysis of randomized trials

Background: Mechanical circulatory support (MCS) with Impella or intra-aortic balloon pump (IABP) is used for high-risk percutaneous coronary intervention (PCI) and/or for cardiogenic shock (CS) due to acute myocardial infarction. We aimed to investigate the efficacy and safety of Impella or IABP when compared with no MCS using a network meta-analysis of randomized controlled trials (RCTs). Methods: EMBASE and MEDLINE were searched through February 2020 for RCT evaluating efficacy of Impella vs. IABP vs. no MCS in patients undergoing high-risk PCI or CS. The primary efficacy outcome was 30 day or in-hospital all-cause mortality whereas the primary safety outcomes were major bleeding and vascular complications. Results: Our search identified nine RCTs enrolling a total of 1,996 patients with high-risk PCI and/or CS. There was no significant difference with Impella or IABP on all-cause mortality when compared with no MCS (Impella vs. no MCS; OR:0.82 [0.35–1.90], p =.65, IABP vs. no MCS; OR:0.77 [0.47–1.28], p =.31, I² = 18.1%). Impella significantly increased major bleeding compared with no MCS (Impella vs. no MCS; OR:7.01 [1.11–44.4], p =.038, I² = 19.2%). IABP did not increase the risk of major bleeding compared with no MCS (OR:1.27 [0.75–2.16], p =.38, I² = 19.2%) but increased vascular complication compared with no MCS (OR:1.92 [1.01–3.64], p =.045, I² = 1.5%). Conclusions: Neither Impella nor IABP decreased all-cause short-term mortality when compared with no MCS for high-risk PCI and/or CS. Moreover, Impella increased major bleeding compared with no MCS.