Microaxial Flow Pump or Standard Care in Infarct-Related Cardiogenic Shock

BackgroundThe effects of temporary mechanical circulatory support with a microaxial flow pump on mortality among patients with ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock remains unclear.MethodsIn an international, multicenter, randomized trial, we assigned patients with STEMI and cardiogenic shock to receive a microaxial flow pump (Impella CP) plus standard care or standard care alone. The primary end point was death from any cause at 180 days. A composite safety end point was severe bleeding, limb ischemia, hemolysis, device failure, or worsening aortic regurgitation.ResultsA total of 360 patients underwent randomization, of whom 355 were included in the final analysis (179 in the microaxial-flow-pump group and 176 in the standard-care group). The median age of the patients was 67 years, and 79.2% were men. Death from any cause occurred in 82 of 179 patients (45.8%) in the microaxial-flow-pump group and in 103 of 176 patients (58.5%) in the standard-care group (hazard ratio, 0.74; 95% confidence interval [CI], 0.55 to 0.99; P=0.04). A composite safety end-point event occurred in 43 patients (24.0%) in the microaxial-flow-pump group and in 11 (6.2%) in the standard-care group (relative risk, 4.74; 95% CI, 2.36 to 9.55). Renal-replacement therapy was administered to 75 patients (41.9%) in the microaxial-flow-pump group and to 47 patients (26.7%) in the standard-care group (relative risk, 1.98; 95% CI, 1.27 to 3.09).ConclusionsThe routine use of a microaxial flow pump with standard care in the treatment of patients with STEMI-related cardiogenic shock led to a lower risk of death from any cause at 180 days than standard care alone. The incidence of a composite of adverse events was higher with the use of the microaxial flow pump. (Funded by the Danish Heart Foundation and Abiomed; DanGer Shock ClinicalTrials.gov number, NCT01633502.)