Impella Versus Non-Impella for Nonemergent High-Risk Percutaneous Coronary Intervention

The benefit of mechanical circulatory support with Impella (Abiomed, Inc., Danvers, Massachusetts) for high-risk percutaneous coronary intervention (HR-PCI) is uncertain. PROTECT III registry data showed improved outcomes with Impella compared with historical data (PROTECT II) but lack a direct comparison with the HR-PCI cohort without Impella support. We retrospectively identified patients meeting the PROTECT III inclusion criteria for HR-PCI and compared this group (non-Impella cohort [NonIMP]) with the outcomes data from the PROTECT III registry (Impella cohort). Baseline differences were balanced using inverse propensity weighting. The coprimary outcome was major adverse cardiac events (MACE) in-hospital and at 90 days. A total of 283 patients at great risk did not receive Impella support; 200 patients had 90-day event ascertainment and were included in the inverse propensity weighting analysis and compared with 504 patients in the Impella cohort group. After calibration, few residual differences remained between groups. The primary outcome was not different in-hospital (3.0% vs 4.8%, p = 0.403) but less in NonIMP at 90 days (7.5% vs 13.8%, p = 0.033). Periprocedural vascular complications, bleeding, and transfusion rate did not differ between groups; however, acute kidney injury occurred more frequently in the NonIMP group (10.5% vs 5.4%, p = 0.023). In conclusion, under identical HR-PCI inclusion criteria for Impella use in PROTECT III, an institutional non-Impella-supported HR-PCI cohort showed similar MACE in-hospital but fewer MACE at 90 days, whereas there was no signal for periprocedural harm with Impella use. These results do not support routine usage of Impella for patients with HR-PCI.