Background: Percutaneous ventricular assist devices (pVADs) are frequently used for the treatment of patients with cardiogenic shock (CS) due to acute myocardial infarction (AMI) and as a support in percutaneous coronary intervention (PCI) for high-risk patients. CS is a clinical condition characterized by inadequate tissue perfusion due to cardiac dysfunction and for 80% of cases it is caused by AMI with left ventricular insufficiency. CS is responsible for about 50% of deaths in patients with myocardial infarction. Usually, PCIs do not require hemodynamic support, which could be however necessary in patients undergoing high-risk PCI. Presently, available pVADs in Europe are Impella 2.5, Impella CP, HeartMate PHP, TandemHeart, PulseCath iVAC2L. The aim of this review is to evaluate the efficacy and safety of pVADs in patients with refractory CS complicating AMI or undergoing high-risk PCI.
Methods: We systematically searched for randomized controlled trials (RCTs) and controlled observational studies in PubMed, Embase and PubMed CENTRAL databases until September 2018. We included studies comparing pVADs with intra-aortic balloon pumps (IABP) or medical therapy in patients with CS complicating AMI or undergoing high-risk PCI. Researchers independently assessed records' eligibility, inclusion and methodological quality of included studies. If possible, data of included studies was combined in a meta-analysis. Risk ratio (RR) and 95% confidence interval (CI) were calculated using a random effects model.
Results: Overall, 8 studies were included. Five studies (3 RCTs and 2 observational studies) evaluated pVADs in patients with SC complicating AMI. Meta-analyses showed that 30-day mortality did not differ between patients treated with pVADs and the control group (RR 1.05, 95% CI 0.84-1.31). However, risk of major bleeding was 2 times higher in patients treated with pVADs compared to controls. Three studies evaluated pVADs in patients undergoing high-risk PCI. Due to the lack of data, it was not possible to combine study results in a meta-analysis. One RCT reported no difference in 30- and 90-day mortality between patients randomized to Impella or IABP. Two non-randomized controlled studies reported no difference in terms of in-hospital all-cause mortality between the two groups.
Conclusions: Our meta-analysis suggests similar results in terms of efficacy and safety between pVADs and control (IABP and medical therapy) for the treatment of patients with CS complicating AMI or undergoing high-risk PCI.