Impella Unloading Fails to Reduce Infarct Size in Anterior STEMI Without Shock

The STEMI Door-to-Unload (DTU) trial found that unloading the left ventricle with Impella CP 30 minutes before PCI in patients with anterior STEMI without cardiogenic shock did not reduce infarct size compared with PCI alone. Importantly, the Impella strategy delayed reperfusion (about 40 minutes to PCI and ~47 minutes total ischemic time) and increased major bleeding (≈30%) and vascular complications, with no improvement in secondary outcomes. The study concludes Impella is not recommended for infarct-size reduction in this population, though it remains relevant for cardiogenic shock; future research may explore alternative strategies.