Delayed Reperfusion With Left-Ventricular Support Evaluated in STEMI DTU

March 28, 2026—The STEMI DTU randomized trial of ST-elevation myocardial infarction and door-to-unloading time showed that delayed reperfusion with left-ventricular (LV) support to reduce heart damage resulted in no significant difference compared with standard immediate percutaneous coronary intervention (PCI) in patients with heart attacks at risk for a large amount of heart damage.

The findings were presented at ACC.26, the American College of Cardiology’s annual scientific session, and simultaneously published online by Navin K. Kapur, MD, et al in JACC. The trial was funded by J&J MedTech Heart Recovery, the parent company of Abiomed, Inc., manufacturer of the Impella CP system temporary circulatory assist device that was used in the study.

According to ACC, the STEMI DTU trial enrolled 527 patients (average age, 61 years; 79% men) at 55 hospitals in the United States, Canada, the United Kingdom, Germany, Italy, and Switzerland); 98% of the patients had complete blockage of the left anterior descending artery. Patients were assigned at random to receive either an LV transaxial flow pump plus a 30-minute waiting period before PCI (the intervention group) or conventional immediate PCI without a LV support pump (the control group).

The primary endpoint of the trial was the extent of patients’ heart-muscle damage, evaluated by MRI at 3 to 5 days after the procedure. The key secondary efficacy endpoint was a composite of death within a year, cardiogenic shock, heart failure, need for a heart transplant or other treatment to support the heart, and the extent of heart muscle damage. The key secondary safety endpoint was major bleeding or blood vessel complications within 30 days.

The ACC press release summarized the findings for the intervention group as follows:

• The extent of heart-muscle damage was not significantly different at 30.8% versus 31.9% for the control group.
• The 30-day rate of device-related major bleeding or blood vessel complications was 30.8% in the intervention group, exceeding the 26.5% predefined performance goal.
• The rates of any major bleeding or vascular complications were 34% versus 6% in the control group.
• Mortality at 1 year was 3.6% versus 5.1% in the control group, a nonstatistically significant difference.

The study will continue to follow patients for up to 5 years, advised ACC. The ACC press release, online here, includes further perspective on the study with commentary by STEMI DTU investigator Gregg W. Stone, MD, expanding on the findings.