Effect of an intra-aortic balloon pump with venoarterial extracorporeal membrane oxygenation on mortality of patients with cardiogenic shock: a systematic review and meta-analysis†.

An intra-aortic balloon pump (IABP) concomitant with venoarterial extracorporeal membrane oxygenation (VA-ECMO) is frequently used to support patients with refractory cardiogenic shock (CS). Because of the lack of evidence of the adjunctive benefit, the goal of the study was to compare the effect of VA-ECMO plus IABP with that of VA-ECMO alone. Systematic searches were conducted to identify studies using PubMed, Embase, the Cochrane Library and the International Clinical Trials Registry Platform. Studies reporting on patients with adult CS treated with VA-ECMO plus IABP or VA-ECMO alone were identified and included. The primary outcome was in-hospital death. The secondary outcomes included neurological, gastrointestinal and limb-related complications. The study protocol was registered at PROSPERO (CRD42017069259). A total of 29 studies comprising 4576 patients were included. The pooled in-hospital deaths of patients on VA-ECMO were 1441/2285 (63.1%) compared with 1339/2291 (58.4%) for patients with adjunctive IABP. VA-ECMO plus IABP was associated with decreased in-hospital deaths [risk ratio (RR) 0.90; 95% confidence interval (CI) 0.85-0.95; P < 0.0001]. Moreover, IABP was related to decreased in-hospital deaths of patients with extracorporeal cardiopulmonary resuscitation, postcardiotomy CS and ischaemic heart disease (RR 0.78; 95% CI 0.64-0.95; P = 0.01; RR 0.91; 95% CI: 0.85-0.98; P = 0.008; RR 0.83; 95% CI 0.73-0.96, P = 0.009). Neurological, gastrointestinal and limb-related complications did not differ significantly between patients on ECMO with and without concurrent IABP. VA-ECMO plus IABP was associated with decreased in-hospital deaths in patients with CS.