Angiographic Stent Thrombosis After Routine Use of Drug-Eluting Stents in ST-Segment Elevation Myocardial Infarction. The Importance of Thrombus Burden

Objectives: This study sought to investigate the impact of thrombus burden on the clinical outcome and angiographic infarct-related artery stent thrombosis (IRA-ST) in patients routinely treated with drug-eluting stent (DES) implantation for ST-segment elevation myocardial infarction (STEMI). Background: There are limited data for the safety and effectiveness of DES in STEMI. Methods: We retrospectively analyzed 812 consecutive patients treated with DES implantation for STEMI. Intracoronary thrombus burden was angiographically estimated and categorized as large thrombus burden (LTB), defined as thrombus burden ≥2 vessel diameters, and small thrombus burden (STB) to predict clinical outcomes. Major adverse cardiac events (MACE) were defined as death, repeat myocardial infarction, and IRA reintervention. Results: Mean duration of follow-up was 18.2 ± 7.8 months. Large thrombus burden was an independent predictor of mortality (hazard ratio [HR] 1.76, p = 0.023) and MACE (HR 1.88, p = 0.001). The cumulative angiographic IRA-ST was 1.1% at 30 days and 3.2% at 2 years, and continued to augment beyond 2 years. It was significantly higher in the LTB compared with the STB group (8.2% vs. 1.3% at 2 years, respectively, p < 0.001). Significant independent predictors for IRA-ST were LTB (HR 8.73, p < 0.001), stent thrombosis at presentation (HR 6.24, p = 0.001), bifurcation stenting (HR 4.06, p = 0.002), age (HR 0.55, p = 0.003), and rheolytic thrombectomy (HR 0.11, p = 0.03). Conclusions: Large thrombus burden is an independent predictor of MACE and IRA-ST in patients treated with DES for STEMI.