Clinical outcomes of ST-Elevation myocardial infarction secondary to stent thrombosis treated by percutaneous coronary intervention.

Abstract

Background: Previous studies suggest that rates of morbidity and mortality are higher in ST-elevation myocardial infarction (STEMI) caused by stent thrombosis (ST) compared to those caused by a de novo lesion. Methods: We studied data from 3,963 patients presenting with STEMI enrolled in the Melbourne Interventional Group registry between 2009 and 2016. They were divided into definite ST group (n = 128) and de novo group (n = 3,835). Short and long-term outcomes were compared. Results: Compared to the de novo group, patients with ST had higher rates of previous myocardial infarction (82% vs. 8.6%, p < 0.001). The majority of ST were very late (>365 days), followed by late (31-365 days) and early ST (64%, 19% and 17%), respectively. Interestingly, the ST group presented with less out-of-hospital cardiac arrest (OHCA) (4.7% vs. 11.5%, p < 0.01) and had shorter symptom-onset-to-door time (STDT), median (IQR) (101 min, 71-162 vs. 114 min, 75- 210, p = 0.03) with no differences in door-to-balloon time, median (IQR) (66 min, 43-79 vs. 67 min, 44-96, p = 0.9), leading to shorter symptom-to-balloon time, median (IQR) (184 min, 132-239 vs. 194 min, 141-291, p = 0.051). There were no significant differences between outcomes for in-hospital, 30-day, 12-months and (NDI-linked) long-term mortality between the two groups. ST was not an independent predictor of 30-day MACE on multivariate analysis (HR 0.8, CI 0.4-1.8, p = 0.75). Conclusion: Patients presenting with STEMI caused by definite ST had similar outcomes to those caused by de novo lesions. A shorter STDT may represent earlier recognition of symptoms in the ST group and possibly contributed to their similar outcome with the de novo group.