Prognostic Significance of Coronary Thrombus in Patients Undergoing Percutaneous Coronary Intervention for Acute Coronary Syndromes : A Subanalysis of the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) Trial

ObjectivesThe objective of this study is to investigate the incidence and clinical implications of thrombus on baseline angiography among patients presenting with non–ST-segment elevation acute coronary syndromes (ACS) undergoing percutaneous coronary intervention (PCI).BackgroundGiven current advances in the pharmacological and mechanical treatment of ACS patients managed with an early invasive strategy, the incidence and prognostic importance of pre-procedural lesion thrombus is warranted.MethodsIn the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial, a total of 3,627 patients with moderate- and high-risk ACS undergoing PCI had their baseline and final post-PCI angiograms analyzed by an independent angiographic core laboratory.ResultsPatients with thrombus (n = 530 [15%]) compared with those without thrombus had higher rates of impaired final epicardial coronary flow (final Thrombolysis In Myocardial Infarction [TIMI] flow grade 3: 89.6% vs. 97.1%, p < 0.0001). Thrombus was an independent predictor of 30 day death (odds ratio [OR]: 3.16 [95% confidence interval (CI): 1.20 to 8.37], p = 0.02), and myocardial infarction (MI) at 30 days (OR: 1.62 [95% CI: 1.17 to 2.24], p = 0.003) and at 1 year (OR: 1.56 [95% CI: 1.16 to 2.08], p = 0.003). Patients with thrombus had significantly higher rates of stent thrombosis (ST) compared with patients without thrombus at 30 days (2.8% vs. 1.1%, p = 0.002) and at 1 year (3.7% vs. 1.8%, p = 0.003), and thrombus was an independent predictor of ST at both 30 days (OR: 2.61 [95% CI: 1.38 to 4.91]) and 1 year (OR: 2.98 [95% CI: 1.64 to 5.42]).ConclusionsPre-procedural thrombus was present in 15% of moderate- and high-risk ACS patients undergoing PCI in the ACUITY trial. Baseline thrombus predicts increased ischemic complications at 30 days including a 3-fold increased risk of death as well as MI up to 1 year. Further evaluation of adjunctive pharmacotherapy is needed in this high-risk population.