Percutaneous short-term active mechanical support devices in cardiogenic shock: A systematic review and collaborative meta-analysis of randomized trials

Aims Evidence on the impact on clinical outcome of active mechanical circulatory support (MCS) devices in cardiogenic shock (CS) is scarce. This collaborative meta-analysis of randomized trials thus aims to investigate the efficacy and safety of percutanzeous active MCS vs. control in CS. Methods and results Randomized trials comparing percutaneous active MCS to control in patients with CS were identified through searches of medical literature databases. Risk ratios (RR) and 95% confidence intervals (95% CI) were calculated to analyse the primary endpoint of 30-day mortality and device-related complications including bleeding and leg ischaemia. Mean differences (MD) were calculated for mean arterial pressure (MAP), cardiac index (CI), pulmonary capillary wedge pressure (PCWP), and arterial lactate. Four trials randomizing 148 patients to either TandemHeart™ or Impella® MCS (n = 77) vs. control (n = 71) were identified. In all four trials intra-aortic balloon pumping (IABP) served as control. There was no difference in 30-day mortality (RR 1.01, 95% CI 0.70 to 1.44, P = 0.98, I² = 0%) for active MCS compared with control. Active MCS significantly increased MAP (MD 11.85 mmHg, 95% CI 3.39 to 20.31, P = 0.02, I² = 32.7%) and decreased arterial lactate (MD - 1.36 mmol/L, 95% CI - 2.52 to - 0.19, I² = 0%, P = 0.02) at comparable CI (MD 0.32, 95% CI - 0.24 to 0.87, P = 0.14, I² = 44.1%) and PCWP (MD - 5.59, 95% -15.59 to 4.40, P = 0.14, I² = 81.1%). No significant difference was observed in the incidence of leg ischaemia (RR 2.64, 95% CI 0.83 to 8.39, P = 0.10, I² = 0%), whereas the rate of bleeding was significantly increased in MCS compared to IABP (RR 2.50, 95% CI 1.55 to 4.04, P < 0.001, I² = 0%). Conclusion Results of this collaborative meta-analysis do not support the unselected use of active MCS in patients with CS complicating AMI.