Percutaneous left ventricular assist device for high-risk percutaneous coronary interventions: Real-world versus clinical trial experience

Background High-risk percutaneous coronary intervention (PCI) supported by percutaneous left ventricular assist devices offers a treatment option for patients with severe symptoms, complex and extensive coronary artery disease, and multiple comorbidities. The extrapolation from clinical trial to real-world practice has inherent uncertainties. We compared the characteristics, procedures, and outcomes of high-risk PCI supported by a microaxial pump (Impella 2.5) in a multicenter registry versus the randomized PROTECT II trial (NCT00562016). Methods The USpella registry is an observational multicenter voluntary registry of Impella technology. A total of 637 patients treated between June 2007 and September 2013 were included. Of them, 339 patients would have met enrollment criteria for the PROTECT II trial. These were compared with 216 patients treated in the Impella arm of PROTECT II. Results Compared to the clinical trial, registry patients were older (70 +/- 11.5 vs 67.5 +/- 11.0 years); more likely to have chronic kidney disease (30% vs 22.7%), prior myocardial infarction (69.3% vs 56.5%), or prior bypass surgery (39.4% vs. 30.2%); and had similar prevalence of diabetes, peripheral vascular disease, and prior stroke. Registry patients had more extensive coronary artery disease (2.2 vs 1.8 diseased vessels) and had a similar Society of Thoracic Surgeons predicted risk of mortality. At hospital discharge, registry patients experienced a similar reduction in New York Heart Association class III to IV symptoms compared to trial patients. Registry patients had a trend toward lower in-hospital mortality (2.7% vs 4.6, P =.27). Conclusions USpella provides a real-world and contemporary estimation of the type of procedures and outcomes of high-risk patients undergoing PCI supported by Impella 2.5. Despite the higher risk of registry patients, clinical outcomes appeared to be favorable and consistent compared with the randomized trial.