- Johnson & Johnson-sponsored STEMI-DTU RCT found Impella CP support >40 minutes before reperfusion did not change infarct size.
- Trial protocol delayed PCI by 30 minutes.
- Pre-PCI TIMI flow and coronary perfusion pressure improved after 30 minutes of Impella support.
- Treatment arm had higher bleeding and vascular complications but no increase in 12-month mortality.
Trial overview
The STEMI-DTU randomized controlled trial tested whether left ventricular (LV) unloading with Impella CP followed by a 30-minute delay before percutaneous coronary intervention (PCI) reduces infarct size in anterior STEMI patients without cardiogenic shock.
Primary outcome
The primary endpoint was neutral: LV support plus delayed reperfusion did not reduce or increase myocardial infarct size versus immediate PCI; investigators note the hypertensive profile of enrolled patients may have limited LV unloading effect.
Key secondary findings
After 30 minutes of Impella support pre-PCI, TIMI flow and coronary perfusion pressure improved and protocol compliance was 100%; patients aged 61+ trended toward smaller infarcts (p=0.056); elevated lactate correlated with larger infarct size across the cohort.
Safety and implications
The treatment arm had higher bleeding and vascular complication rates but no increase in 12-month mortality; results support further mechanistic studies, including testing adjunct pharmacotherapies during the pre-PCI unloading window and targeted research in older or high-lactate subgroups.
