Study Supports Safety of Door to Unloading With Abiomed's Impella CP System in STEMI Patients
November 11, 2018—Abiomed, Inc. announced the results of a trial investigating "door to unloading" (DTU) with the company's Impella CP system in patients with acute myocardial infarction. Results were presented by Navin Kapur, MD, at the 2018 American Heart Association (AHA) scientific sessions held November 10–12 in Chicago, Illinois. The study findings were simultaneously published online by Dr. Kapur et al in Circulation.
The multicenter, prospective, randomized controlled DTU trial enrolled 50 patients to investigate the safety and feasibility of left ventricular unloading with Abiomed’s Impella CP for 30 minutes before reperfusion or Impella use followed by immediate reperfusion in patients presenting with anterior ST-segment elevation myocardial infarction (STEMI) without cardiogenic shock.
According to Abiomed, the study found that unloading first and delaying reperfusion by 30 minutes did not increase 30-day major adverse cardiovascular and cerebrovascular events or infarct size compared to the immediate reperfusion arm of the trial.
The investigators reported that it is feasible to delay reperfusion in a STEMI patient in a clinical trial, as demonstrated by a 100% adherence to the 30-minute unloading protocol and 100% Impella CP insertion success in both study arms. Additionally, unloading the left ventricle for 30 minutes before reperfusion appears to reduce infarct size as a percentage of area at risk among patients with an ST-segment elevation sum > 6.
Dr. Kapur and William O'Neill, MD, are Coprincipal Investigators of the study. Dr. Kapur is Executive Director of the CardioVascular Center for Research and Innovation at Tufts Medical Center in Boston, Massachusetts. Dr. O’Neill is Medical Director of the Center for Structural Heart Disease at Henry Ford Hospital in Detroit, Michigan.
In Abiomed's announcement, Dr. Kapur commented, “If a reduction of infarct size from unloading before reperfusion is confirmed in a future trial, this concept would enhance the existing guidelines of immediate reperfusion for STEMI patients. 75% of patients experiencing their first heart attack will develop heart failure within 5 years, so new approaches are needed to reduce infarct size and prevent heart failure. Preclinical nonhuman datasets show unloading the left ventricle prior to reperfusion activates a cardioprotective program that reduces reperfusion injury and could improve the current standard of care.”
Dr. O'Neill added, “This safety and feasibility study gives us hope that we can help STEMI heart attack patients in the future by unloading the heart muscle with delayed revascularization. The planned pivotal randomized controlled trial will further examine whether unloading with Impella CP for 30 minutes prior to reperfusion will potentially slow down or avoid the development of heart failure.”
Abiomed noted that the safety and feasibility study design was approved by the FDA, with an independent steering committee and data and safety monitor overseeing the trial and a blinded clinical events committee independently adjudicating study endpoints. Infarct size was evaluated using a cardiac magnetic resonance imagingMRI technique assessed at a blinded core lab.
The company also announced that it will move forward with a pivotal, multicenter, prospective, randomized controlled trial comparing unloading with delayed reperfusion to the current standard of care (immediate reperfusion without Impella). The pivotal trial, conducted with the agreement of the FDA, is planned to begin in 2019.