Haemodynamic efficacy of microaxial left ventricular assist device in cardiogenic shock: a systematic review and meta-analysis

The Impella percutaneous mechanical circulatory support device is designed to augment cardiac output and reduce left ventricular wall stress and aims to improve survival in cases of cardiogenic shock. In this meta-analysis we investigated the haemodynamic effects of the Impella device in a clinical setting. We systematically searched all articles in PubMed/Medline and Embase up to July 2019. The primary outcomes were cardiac power (CP) and cardiac power index (CPI). Survival rates and other haemodynamic data were included as secondary outcomes. For the critical appraisal, we used a modified version of the U.S. Department of Health and Human Services quality assessment form. The systematic review included 12 studies with a total of 596 patients. In 258 patients the CP and/or CPI could be extracted. Our meta-analysis showed an increase of 0.39 W [95% confidence interval (CI): 0.24, 0.54], (p = 0.01) and 0.22 W/m(2) (95% CI: 0.18, 0.26), (p < 0.01) for the CP and CPI, respectively. The overall survival rate was 56% (95% CI: 0.50, 0.62), (p = 0.09). The quality of the studies was moderate, mostly due to the presence of confounders. Our study suggests that in patients with cardiogenic shock, Impella support seems effective in augmenting CP(I). This study merely investigates the haemodynamic effectiveness of the Impella device and does not reflect the complete clinical impact for the patient.