A pivotal, multicentre clinical trial is exploring the use of an Impella heart pump (Abiomed) to unload the left ventricle for 30 minutes prior to coronary revascularisation. The aim of the trial is to test the hypothesis that unloading the left ventricle for 30 minutes prior to revascularisation reduces myocardial damage from a myocardial infarction and, as a result, leads to a reduced risk of a patient developing heart failure. The enrolment of the first patient in the STEMI DTU (ST-elevation myocardial infarction door-to-unloading) randomised trial enrolment took place at Spectrum Health (Grand Rapids, USA).
A press release reports that a study in Circulation determined that 47% of women and 36% of men over the age of 45 will die within five years of their first myocardial infarction. It adds that research published in Journal of the American College of Cardiology found 75% of patients experiencing their first myocardial infarction will develop heart failure within five years. If the STEMI DTU pivotal trial produces positive results, according to the press release, it could mean that a therapy is available to annually benefit the 200,000 myocardial infarction patients in the USA and more than 4m patients outside the USA.
The multicentre, two-arm randomised controlled trial plans to enrol 668 patients undergoing treatment for a ST-segment elevation myocardial infarction (STEMI). Half the patients will be randomised to receive 30 minutes of left ventricular unloading with the US Food & Drug Administration (FDA) approved Impella CP heart pump prior to having blood flow restored to their blocked arteries. The other half will receive immediate reperfusion, the current standard of care. The primary endpoint is infarct size as a percent of left ventricular mass, measured at 3–5 days using cardiac MRI.
The press release states that a pilot safety randomised controlled trial successfully demonstrated a therapy of 30 minutes of unloading with Impella prior to reperfusion is safe and feasible. The pilot trial results were announced as a late-breaking study at the American Heart Association (AHA) 2018 Scientific Sessions and simultaneously published in Circulation.
Gregg W Stone (The Zena and Michael A Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, USA), a STEMI DTU steering committee member, says: “Patients with large anterior myocardial infarction continue to have unacceptably high rates of death and heart failure despite successful primary percutaneous coronary intervention (PCI). The STEMI DTU trial will demonstrate whether Impella unloading of the left ventricle prior to reperfusion therapy reduces infarct size and thereby improves the prognosis of this high-risk patient cohort.”