Non-stenting strategy is not inferior to stent implantation in patients with acute ST-segment elevated myocardial infarction and high thrombus burden and intermediate stenotic culprit lesion.

Abstract

According to European Society of Cardiology (ESC) as well as American College of Cardiology/American Heart Association (ACC/AHA) guidelines, primary stenting is recommended for patients with acute ST-segment elevation myocardial infarction (STEMI); however, in-stent thrombosis is a life-threatening early adverse event that could lead to acute myocardial infarction (AMI) or even cardiac death. On the other hand, in-stent restenosis is a late adverse event that could result in recurrent readmission and revascularization. We compared a non-stenting (NS) strategy to a stenting (S) strategy in terms of incidence of major adverse cardiac events (MACEs) for patients with acute STEMI and high thrombus burden. We performed a post hoc analysis of our prior multicenter, prospective cohort study (ChiCTR1800019923) among 51 eligible patients with acute STEMI and high thrombus burden. All participants received percutaneous coronary intervention (PCI) with a deferred-stenting strategy (second procedure performed within 48-72 h after primary PCI). Either NS or S strategies were carried out among patients. Primary outcomes were follow-ups of MACEs at 1, 3, 6, and 12 months. Intravenous ultrasound (IVUS) and quantitative flow ratio (QFR) evaluation were performed. In our post hoc analysis of 51 patients (21 with NS and 30 with S), baseline clinical and interventional characteristics were well matched between the 2 groups, to the exception of culprit lesion length. Incidence of MACEs was not significantly different between the 2 strategies in-hospital (P=0.56) and in follow-ups at 1 (P=0.41), 3 (free of events), 6 (P=0.71), and 12 (P=0.68) months. Culprit lesions of NS tended to be "low-risk" [minimum lumen area (MLA) 4.27±1.02 vs. 3.80±1.32 mm2, P=0.36] and plaque burden (70.79%±6.46% vs. 76.97%±6.76%, P=0.03) when compared with culprit lesions of S in IVUS evaluation. Evaluation of QFR showed more sufficient physiological reperfusion improvement with NS than with S [two-dimensional (2D) QFR: 0.85±0.09 vs. 0.79±0.13, P=0.10 and 3D QFR: 0.86±0.08 vs. 0.78±0.15, P=0.02]. The NS strategy did not increase MACEs in-hospital and at 1, 3, 6, and 12 months. The NS can be a safe option when meeting certain criteria for patients with STEMI and a high thrombus burden.