PROTECT I study results evaluating the feasibility and effectiveness of Impella 2.5 circulatory assist device in high-risk percutaneous coronary intervention (PCI) procedures have been published. The study named A Prospective Feasibility Trial Investigating the Use of the Impella 2.5 System in Patients Undergoing High-Risk Percutaneous Coronary Intervention (The PROTECT I Trial) founded that the Impella 2.5 system is safe, easy to use, and provides hemodynamic support during high-risk PCI. The trial enrolled 20 patients undergoing high-risk PCI at seven centers between July 2006 and April 2007. Patients 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 Impella 2.5 is a FDA 510(k) cleared device in June 2008 for partial circulatory support for periods up to six hours. The device is percutaneously inserted in the catheterization lab (cath lab) via the femoral artery into the left ventricle. Abiomed is also conducting two US clinical studies comparing the Impella 2.5 to the IABP (Protect II for high-risk percutaneous coronary intervention, or PCI; and Recover II for acute myocardial infarction, AMI or heart attack).