0459: Super-Minimalist Immediate Mechanical Intervention (Super-MIMI) study

Purpose To evaluate the safety of extended-delay stenting (>7 days between procedures) in the setting of percutaneous coronary intervention (PCI) for acute ST-segment elevation myocardial infarction (STEMI). Methods This ongoing prospective observational study is being conducted in STEMI patients with a high thrombus burden in the infarct-related artery (IRA). Patients are enrolled if the operator decides to try to restore the best TIMI flow with the thinnest tool and defer stent implantation for >7 days under optimal anticoagulation to reduce thrombus burden. The primary endpoint is the composite of reocclusion of the IRA or sudden death between the two procedures, and deterioration of the flow (from the final flow achieved after the first procedure to the initial flow at the second procedure). Results Between January 2014 and January 2015, 127 patients (of 135 we will enroll) were enrolled at 14 centres: 110 were men and the mean age±SD was 57.1±13.0 years. 98 patients underwent a primary PCI as the first procedure and 29 patients underwent PCI after fibrinolysis. The final TIMI flow at the first procedure was 3 in 119 patients, 2 in 7 patients, and 1 in 1 patient and the residual culprit lesion was 61±24%. Glycoprotein IIb/IIIa inhibitor in 42 patients. The second procedure was performed between 7 and 26 days after the first. None of the patients died between the two procedures; 1 patient experienced a reocclusion of the IRA In all cases, initial TIMI flow in the IRA (at the start of the second procedure) was the same as or better than the final flow after the first procedure. A stent was implanted in 80 patients, whereas no significant lesion was documented in 47 patients. Final results will be presented at the meeting. Conclusions In PCI for acute STEMI, when the thrombus burden is high, stenting delayed by 7-26 days with intensive antithrombotic cover appears safe, with only 1 of 130 patients developing an IRA reocclusion.