Abiomed‘s Impella 2.5 Percutaneous Circulatory Support System, the world’s smallest left ventricle heart pump, has received conditional approval from the FDA to begin MINI-AMI, “a prospective, randomized, controlled multi-site trial to assess the potential role of the Impella® 2.5 in reducing infarct size in patients with ST-elevation myocardial infarction (STEMI).” As we have reported before, the device has already been approved by the FDA for use in patients for up to six hours, to augment cardiac output by as much as 2.5 liters per minute in patients with acute left ventricular failure, who are also suffering from ongoing acute MI.
More about the study:
The primary objective of this study is to evaluate whether the adjunctive use of the Impella 2.5 for 24 hours following primary percutaneous intervention (PCI) for STEMI has the potential to limit the infarction of at-risk myocardium compared to primary PCI with routine post-PCI care. According to the American Heart Association (AHA), 400,000 patients in the U.S. suffer from STEMIs every year.
“This pilot study will determine whether the Impella 2.5 can be the first device to actually shrink infarct size," said Principle Investigator Jeffrey Moses, M.D., New York-Presbyterian Hospital and Columbia University Medical Center. “Today, heart attack survivors can suffer considerable subsequent disability from damaged heart muscle. The intent of this study is to investigate the unique unloading capabilities of Impella 2.5 and its effect in potentially reducing infarct size and improving quality of life for patients.”
The primary endpoint of the study will be a cardiac MRI-assessed ratio of the final infarct area to the total area of myocardium that was at risk. This ratio will be measured at three to five days after treatment and then again at 90 days. A total of 50 patients at five hospital sites will be randomized to Impella 2.5 support or the institution’s standard of care with no circulatory support post-PCI. The study is based on the hypothesis that Impella’s ability to directly unload the left ventricle will reduce overall infarct area relative to the total area at risk which has been demonstrated in previous animal studies.
The MINI-AMI study will enroll patients with acute anterior STEMI or large inferior STEMI, primary PCI performed within five hours of the onset of symptoms, patients undergoing emergent primary PCI of one culprit lesion in one major coronary vessel, and successful revascularization of the native coronary artery at the end of PCI.
In other, more negative news, Abiomed has ended the Protect II trial of Impella 2.5, “based on a futility determination at the planned interim analysis regarding the primary end-point, which the company views as likely to be due to unanticipated confounding variables related to the use of rotational atherectomy,” according to a press release. In other words, the reason for suspension were unanticipated events that resulted from overtly enthusiastic cardiologists adding atherectomies to the angioplasty. The following was released by the company:
“Atherectomy was an unanticipated variable which resulted from the operators’ decision to ‘do more with Impella.’ Our investigators had unblinded knowledge of the treatment arm after randomization,” said William O’Neill, M.D., University of Miami and Principal Investigator of the PROTECT II study. “It is interesting that operators felt that they could do more complex interventions once randomized to Impella and this in and of itself is an important finding.”
More from MassDevice: Over-eager docs prompt Abiomed to halt Protect II trial …;
Dow Jones Newswires: Abiomed Ends Impella Study On Unanticipated Variable …
Press releases: Abiomed Receives Conditional FDA Approval for Study with Impella 2.5 in Reducing Heart Muscle Damage Following PCI in STEMI Patients…; Abiomed Ends Protect II Study and Announces Interim Results, Detailed Clinical Analysis to Be Presented at ACC 2011 …
Product page: Impella 2.5
Flashbacks: Impella 2.5 Heart Pump Given Green Light in US; Impella Percutaneous VAD to be Studied for Acute MI Patients; impella® recover LV; Impella Recover Devices Approved in Germany for Reimbursement