Impact of residual platelet reactivity on reperfusion in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.

Abstract

Whether high platelet reactivity (HPR) immediately after diagnostic angiography is associated with worse coronary reperfusion prior to and after primary percutaneous coronary intervention (PPCI) for ST-segment elevation myocardial infarction (STEMI) is unknown. This study aimed to assess the impact of P2Y12-mediated HPR on angiographic outcomes in patients with STEMI undergoing PPCI. STEMI patients undergoing PPCI and pretreated with a P2Y12 receptor antagonist underwent platelet function testing with the VerifyNow™ assay at the time of angiography. Light transmission aggregometry (LTA) was performed in a subgroup. HPR was defined according to expert consensus definitions. Pre-PCI coronary patency, thrombotic burden and indices of impaired post-PCI reperfusion were compared between HPR and non-HPR patients. Among 164 patients, the prevalence of VerifyNow™-derived HPR was 71.3% at a median (interquartile range (IQR)) of 55 (40-75) minutes after a P2Y12 inhibitor loading dose. Compared with non-HPR patients, those with HPR had significantly lower rates of pre-PCI Thrombolysis in Myocardial Infarction (TIMI) flow grades 2 or 3 (51.1% vs. 32.5%, p = 0.04), higher rates of thrombus score (TS) grade 3/4 (29.8% vs. 52.1%, p = 0.015) and 4 (14.9% vs. 32.5%, p = 0.037) and lower median (IQR) corrected TIMI frame count (cTFC; 23.2 (15.8-32.5) vs. 26.0 (21.0-35.0), p = 0.02), respectively. These findings were consistent using LTA-based data. HPR and TS grade 4 were predictors of higher cTFC. In patients with STEMI undergoing PPCI pretreated with P2Y12 receptor inhibitors, pre-PPCI HPR was found to be associated with lower pre-PCI coronary patency, higher thrombotic burden and a worse index of post-PCI coronary reperfusion.