Which Intraprocedural Thrombotic Events Impact Clinical Outcomes After Percutaneous Coronary Intervention in Acute Coronary Syndromes?: A Pooled Analysis of the HORIZONS-AMI and ACUITY Trials

Abstract

Objectives: This study sought to determine the extent to which individual components of intraprocedural thrombotic events (IPTEs) are associated with adverse events.

Background: IPTEs occurring during percutaneous coronary intervention (PCI) are associated with adverse in-hospital and late outcomes in patients with acute coronary syndromes.

Methods: A total of 6,591 patients who underwent PCI for non-ST-segment elevation acute coronary syndromes/ST-segment elevation myocardial infarction in the ACUITY (Acute Catheterization and Urgent Intervention Triage StrategY) and HORIZONS-AMI (Harmonizing Outcomes with RevascularIZatiON and Stents in Acute Myocardial Infarction) trials underwent detailed frame-by-frame core laboratory angiographic analysis to assess for IPTEs. The associations of IPTE components with death, major bleeding, and major adverse cardiac events at 30 days were assessed using univariable analyses and multivariable models.

Results: The overall incidence of IPTEs was 7.7%, with a greater incidence in ST-segment elevation myocardial infarction patients (12.2%) compared with non-ST-segment elevation acute coronary syndromes patients (3.5%). Specific components of IPTEs included no-reflow/slow reflow in 58.0%, new/worsened thrombus in 35.3%, distal embolization in 34.9%, abrupt closure in 19.8%, and intraprocedural stent thrombosis (IPST) in 9.5% of patients. Each IPTE component was independently associated with 30-day death, major bleeding, and MACE in multivariable models, with the strongest association observed for IPST (MACE hazard ratio: 7.51 [95% confidence interval: 4.36 to 12.94]).

Conclusions: The occurrence of IPTEs is not infrequent among high-risk acute coronary syndromes patients undergoing PCI, and each IPTE component was associated with subsequent adverse events. Although IPST represented <10% of IPTE events overall, it was the component with the strongest association with adverse events.

Keywords: acute coronary syndrome(s); intraprocedural thrombotic event(s); percutaneous coronary intervention.