Angiographic characteristics of definite stent thrombosis: role of thrombus grade, collaterals, epicardial coronary flow, and myocardial perfusion.

Abstract

To characterize the prevalence of thrombus burden, collateral vessels to the infarct-related artery, epicardial coronary artery flow, and myocardial perfusion in patients with angiographically confirmed definite stent thrombosis (ST), and to define their relationship with associated treatments and outcomes. Angiographic characteristics of ST are not well defined. All cases of angiographically determined ST at five academic hospitals from 2005 to 2012 were reviewed. Demographic, procedural, and angiographic characteristics were recorded. In-hospital and 1-year follow-up data were obtained. Among 205 cases of angiographic definite ST (60 ± 8 years; 87% male), the majority presented with late/very late ST (69%) and STEMI (66%). High-risk angiographic findings at presentation included thrombus grade 4-5 (87%), absence of collateral vessels (76%), and reduced initial TIMI 3 flow (90%). Final TIMI 3 flow was achieved in 90% of patients and was associated with greater use of aspiration thrombectomy (60% vs. 25%; P = 0.003), glycoprotein IIb/IIIa inhibitors (80% vs. 30%, P < 0.001), and repeat stenting (67% vs. 10%, P < 0.001). A final myocardial perfusion grade of 2-3 was achieved in 79% of patients and was associated with greater use of aspiration thrombectomy (61% vs. 36%, P = 0.003). After multivariable logistic regression, aspiration thrombectomy (AOR 2.6, 95% CI 1.3-5.2) and implantation of a new stent (AOR 2.1, 95% CI 1.1-4.3) were associated with optimal combined epicardial flow and myocardial perfusion. At 1-year follow-up, significantly lower risk of repeat ST (HR 0.1; 95% CI 0.1,0.2; P < 0.001) among patients with initial TIMI 3 flow at index ST was observed. The majority of ST patients present with late/very late ST with high thrombus burden and STEMI. Presence of collateral vessels and low thrombus burden is cardioprotective, while reduced initial TIMI flow is associated with larger infarct size and recurrent ST. Aspiration thrombectomy and repeat stenting are associated with improved epicardial coronary artery flow and myocardial perfusion among patients treated for ST. © 2014 Wiley Periodicals, Inc.