Abiomed's Impella 2.5 Heart Pump Shows Reduced Kidney Injury in High-Risk PCI

March 9, 2017—Abiomed, Inc. announced the publication of a study showing that use of hemodynamic support with the company's Impella 2.5 heart pump during high-risk percutaneous coronary intervention (HRPCI) can reduce the risk of acute kidney injury even when those patients had preexisting kidney disease and low ejection fraction (EF). The study was published by Michael P. Flaherty, MD, et al in Circulation Research (2017;120:692–700).

According to Abiomed, the new study builds upon earlier data from the PROTECT II randomized clinical trial, which found kidney injury rates were numerically lower when more contrast was used during HRPCI, and adds to the growing body of evidence of the benefits of hemodynamic support with Impella during HRPCI.

As summarized by the company, investigators in the retrospective, single-center study analyzed the procedure and clinical outcomes of 230 patients with an EF ≤ 35% before undergoing HRPCI. Half of the patients studied were supported with Impella 2.5 during their procedure and were compared with a matched-controlled cohort of 115 patients undergoing HRPCI without Impella. In the study, Impella-supported patients were more likely to present with comorbidities at baseline such as left main and three-vessel disease, and lower EF which led to longer median procedure times and greater median volume of contrast in the Impella arm.

The investigators found only 5.2% of the Impella-supported patients developed acute kidney injury​ postprocedure compared with 27.8% in the unsupported patients’ cohort, despite increased risk factors for kidney injury in the Impella arm. In addition, < 1% of Impella-supported patients required hemodialysis after the intervention compared with 6.1% of unsupported patients. This outcome suggests that patients who did not receive Impella were six times more likely to need dialysis. The mean length of stay was also longer in the unsupported group.

In Abiomed's announcement, Dr. Flaherty, the study's primary investigator commented, “A substantial number of HRPCI patients have both severely reduced left ventricular function and underlying kidney disease, and during their procedure, these patients are exposed to high levels of contrast dye, which further compromises kidney function. We found that, despite severely reduced ejection fractions and baseline chronic kidney disease, Impella-supported patients were six times less likely to develop acute kidney injury, underscoring the importance of Impella as part of a renal protective strategy during HRPCI.”

Dr. Flaherty continued, “We believe that kidney injury resulting from episodic decrease in flow during HRPCI can be reduced with Impella support and that stagnation of contrast in the renal tubules may be minimized. The use of Impella, then, is especially important as more patients undergo complete revascularization rather than staged procedures, ostensibly improving periprocedural kidney blood flow and reducing the toxic effects of contrast dye despite low EF, baseline renal insufficiency, and longer procedure times.” Dr. Flaherty is Associate Professor of Medicine and Physiology at University of Louisville School of Medicine in Louisville, Kentucky.