Randomized comparison of intra-aortic balloon support with a percutaneous left ventricular assist device in patients with revascularized acute myocardial infarction complicated by cardiogenic shock

Abstract

Mortality in cardiogenic shock (CS) following acute myocardial infarction (AMI) remains unacceptably high despite percutaneous coronary intervention (PCI) of the infarcted artery and use of intra-aortic balloon pump (IABP) counterpulsation. A newly developed percutaneous left ventricular assist device (VAD) (Tandem Heart, Cardiac Assist, Pittsburgh, PA, USA) with active circulatory support might have positive haemodynamic effects and decrease mortality. Patients in CS after AMI, with intended PCI of the infarcted artery, were randomized to either IABP (n=20) or percutaneous VAD support (n=21). The primary outcome measure cardiac power index, as well as other haemodynamic and metabolic variables, could be improved more effectively by VAD support from 0.22 [interquartile range (IQR) 0.19-0.30] to 0.37 W/m2 (IQR 0.30-0.47, P<0.001) when compared with IABP from 0.22 (IQR 0.18-0.30) to 0.28 W/m2 (IQR 0.24-0.36, P=0.02; P=0.004 for intergroup comparison). However, complications like severe bleeding (n=19 vs. n=8, P=0.002) or limb ischaemia (n=7 vs. n=0, P=0.009) were encountered more frequently after VAD support, whereas 30 day mortality was similar (IABP 45% vs. VAD 43%, log-rank, P=0.86). Haemodynamic and metabolic parameters can be reversed more effectively by VAD than by standard treatment with IABP. However, more complications were encountered by the highly invasive procedure and by the extracorporeal support.