Feasibility and Safety of Low-Dose Intra-Coronary Tenecteplase During Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction (ICE T-TIMI 49)

ABSTRACT Following primary percutaneous coronary intervention (PPCI) for ST segment elevation myocardial infarction (STEMI), microvascular perfusion is often impaired secondary to thrombotic embolization. Intracoronary (IC) fibrinolytic administration may reduce thrombotic burden and distal embolization. The ICE-T-TIMI-49 study evaluated the feasibility and safety of low-dose IC tenecteplase (TNK) during PPCI. The study randomized 40 PPCI patients to a volume matched bolus of IC TNK (4 mg) (n=20) or IC saline placebo (n=20) before and following PPCI. The primary endpoint was percent diameter stenosis of the culprit lesion following first bolus. The primary endpoint did not differ between IC placebo (median 100%, interquartile range [IQR] 83.0,100.0) and IC TNK (median 100% stenosis, IQR 91.0,100.0; p=0.522). However, the proportion of patients with reduction in thrombus following first bolus tended to be greater with IC TNK (placebo: 12.5% versus IC TNK: 40.0%, p=0.133). Following PPCI, the corrected Thrombolysis In Myocardial Infarction (TIMI) frame count (cTFC) was lower (faster) with placebo (16.0 frames [IQR 12.0,24.0] versus 24.0 frames [22.0,32.0], p=0.045) due to a trend towards greater frequency of hyperemia (cTFC