Intraprocedural Thrombotic Events During Percutaneous Coronary Intervention in Patients With Non–ST-Segment Elevation Acute Coronary Syndromes Are Associated With Adverse Outcomes : Analysis From the ACUITY (Acute Catheterization and Urgent Intervention T

ObjectivesThe purpose of this study was to assess the prognostic impact of intraprocedural thrombotic events (IPTE) during percutaneous coronary intervention (PCI).BackgroundIschemic complications of PCI are infrequent but prognostically important. How often these events are a consequence of intraprocedural complications is unknown, with only limited data assessing the occurrence and importance of IPTE.MethodsA total of 3,428 patients who underwent PCI for non–ST-segment elevation acute coronary syndrome in the ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) trial underwent detailed frame-by-frame core laboratory angiographic analysis. An IPTE, defined as the development of new or increasing thrombus, abrupt vessel closure, no reflow, slow reflow, or distal embolization at any time during the procedure, occurred in 121 patients (3.5%).ResultsPatients with IPTE had higher in-hospital, 30-day, and 1-year major adverse cardiac event rates than patients without IPTE (25.6% vs. 6.3% in-hospital, 30.6% vs. 9.3% at 30 days, and 37.0% vs. 20.5% at 1 year; p < 0.0001 for each). An IPTE was strongly associated with Q-wave myocardial infarction and out-of-laboratory definite/probable stent thrombosis (in-hospital 3.3% vs. 0.5%, p = 0.006; 30 days 5.8% vs. 1.3%, p < 0.0001; and 1 year 6.7% vs. 2.0%, p = 0.0002). Unplanned revascularization, target vessel revascularization, and major bleeding not associated with coronary artery bypass graft surgery were also increased among patients with IPTE, as was overall 30-day mortality (3.3% vs. 0.7%, p = 0.002). Moreover, IPTE was an independent predictor of 30-day and 1-year composite death/myocardial infarction, stent thrombosis, and major adverse cardiac events.ConclusionsAlthough infrequent among patients undergoing early PCI for moderate and high-risk non–ST-segment elevation acute coronary syndrome, IPTE was strongly associated with subsequent adverse outcomes including death, myocardial infarction, and stent thrombosis.