Researchers from Brigham and Women's Hospital (Boston, MA, USA), Massachusetts General Hospital (MGH; Boston, USA), the Texas Heart Institute (Houston, USA), and four other hospitals enrolled 20 patients undergoing high-risk PCI in the PROTECT I study between July 2006 and April 2007. Eligible patients for implantation of the Impella 2.5 circulatory assist device had left ventricular ejection fraction (EF) of less than 35% and were required to undergo PCI on either an unprotected left main coronary artery or the last patent coronary conduit. The primary safety end point was the incidence of major adverse cardiac events at 30 days; the primary efficacy end point was freedom from hemodynamic compromise during PCI, defined as a decrease in mean arterial pressure below 60 mm Hg for over 10 minutes.

The results of the study showed that the Impella 2.5 device was implanted successfully in all patients. The mean duration of circulatory support was 1.7 hours. Mean pump flow during PCI was 2.2 liters per minute. At 30 days, the incidence of major adverse cardiac events was 20%; 2 patients had a periprocedural myocardial infarction (MI), and 2 patients died at days 12 and 14. There was no evidence of aortic valve injury, cardiac perforation, or limb ischemia. Two patients (10%) developed mild, transient hemolysis without clinical sequelae. None of the patients developed hemodynamic compromise during PCI. The study was published in the February 2009 issue of the Journal of American College of Cardiology (JACC).

"The Impella 2.5 is poised to change the standard of care in our efforts to combat heart disease and its devastating after-effects," said participating cardiologist Igor Palacios, M.D., director of interventional cardiology at MGH. "The PROTECT I trial enrolled a very sick patient population and demonstrated that the device works and validated its impressive safety profile, showing no valve, blood or vascular damage, no instances of stroke and a low adverse event rate."

The Impella 2.5, a product of Abiomed (Danvers, MA, USA) is intended for partial circulatory support for periods of up to six hours. It is inserted percutaneously in the catheterization lab via the femoral artery into the left ventricle. Up to 2.5 liters of blood per minute are delivered by the pump from the left ventricle into the ascending aorta, providing the heart with active support in critical situations. The device has been approved by the European Community (CE Marking) and the U.S. Food and Drug Administration (FDA), among others.

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Brigham and Women's Hospital
Massachusetts General Hospital
Texas Heart Institute
Abiomed