Enrollment commences in MINI-AMI study of Impella in STEMI patients

Abiomed, Inc. (NASDAQ: ABMD), a leading provider of breakthrough heart support technologies, today announced the first patient enrolled in MINI-AMI, an FDA prospective, randomized, controlled multi-center study to assess the role of 24-hours of direct unloading of the left ventricle with Impella® 2.5 support to reduce infarct size in patients with ST-elevation myocardial infarction (STEMI) without cardiogenic shock. The patient was enrolled at the Texas Heart Institute at St. Luke's Episcopal Hospital in Houston and implanted by Guilherme Silva, M.D.

“The MINI-AMI study will give us a first look at the potential benefit of Impella in this large patient population, which is currently untreated by any type of direct ventricular support.”

MINI-AMI is a feasibility study designed with the exploratory intent to determine whether direct unloading of the left ventricle can be effective in treating this stable STEMI patient population, which represents 330,000 patients a year, according to the American College of Cardiology (ACC) and American Heart Association (AHA) 2009 Guidelines for STEMI and percutaneous coronary intervention (PCI). Although this study is not powered to show a statistical difference in the primary endpoint, the results will provide guidance towards future larger investigations. The study will enroll a total of 60 acute myocardial infarction (AMI) patients requiring primary PCI, including 10 roll-in patients at a maximum of five institutions. Patients will be randomized to PCI+Impella vs. PCI-only arms. The study will assess the infarct size using a magnetic resonance imaging (MRI) technique.

"We are very excited to be the first to enroll in the exploration of infarct size reduction," said Andrew Civitello, M.D, principal investigator at Texas Heart Institute at St. Luke's Episcopal Hospital. "The MINI-AMI study will give us a first look at the potential benefit of Impella in this large patient population, which is currently untreated by any type of direct ventricular support."

Relative to this stable STEMI patient population, results were recently released from the Counterpulsation to Reduce Infarct Size Pre-PCI Acute Myocardial Infarction (CRISP AMI) trial. The CRISP AMI trial determined that routine intra-aortic balloon pump (IABP) placement prior to reperfusion in patients with STEMI without cardiogenic shock, did not reduce myocardial infarct size. A total of 337 patients were randomized at 30 sites, with one group receiving IABP+PCI and the other group receiving PCI treatment alone. The median infarct size was 37.5% in patients treated with PCI-only and trended larger in the IABP+PCI arm with 42.1% infarct size.

Although the recently published CRISP AMI results did not show an infarct size reduction or clinical benefit of IABP and further discourages its routine use in this category of patients, the study itself has provided insight on the extent of the infarct size in stable STEMI patients and measuring outcomes of AMI beyond the survival benefit.

"The large infarcts observed in the CRISP AMI trial overall emphasize a significant clinical need for patients who are treated within recommended door-to-balloon times and still sustain significant myocardial damage. It is a great example of the need for an effective myocardial salvage strategy which can be provided through direct ventricular unloading by a device such as Impella," said Jeff Moses, M.D., Columbia University Medical Center/New York-Presbyterian Hospital and co-principal investigator of the MINI-AMI study.

The CRISP-AMI trial results were published online by the Journal of the American Medical Association and were recently discussed in a TCTMD webcast on September 13.

Source Abiomed, Inc.