Clinical outcomes of drug-eluting stent use in patients with ST elevation myocardial infarction

Abstract

Aim: Randomised trials using drug-eluting stents (DES) in ST elevation myocardial infarction (STEMI) have shown mixed results, and excluded patients at the highest risk of adverse outcomes. We aimed to determine the real world clinical outcomes of DES and compare these with bare-metal stents (BMS) in an unrestricted observational study of patients presenting with STEMI.

Methods: 564 consecutive patients undergoing primary PCI for STEMI were prospectively enrolled in the Melbourne Interventional Group registry (August 2004 to May 2006). The choice of using DES was at the operator's discretion, yet restricted to patients considered at highest risk of restenosis [e.g. diabetes, long lesions (>20 mm) and small target vessels (<2.5 mm)]. Clinical, procedural, and 12-month outcomes of patients receiving DES were evaluated and compared to BMS.

Results: DES were used in 45% of patients presenting with STEMI. The rates of cardiogenic shock were similar in the DES and BMS groups (10.2 vs. 11%, p=0.71). In-hospital outcomes were not significantly different with respect to death (4.7 vs. 7.2%, p=0.23), major adverse cardiac events (MACE) (10.6 vs. 11.3%, p=0.80) or stent thrombosis (1.7 vs. 0.3%, p=0.71). At 12 months, target vessel revascularisation (TVR) in patients with DES was 10.2% vs. 7.2% in BMS (p=0.22). On propensity score adjusted multivariate analyses, the only independent predictor of 12-month MACE was presentation with cardiogenic shock (OR 2.59, 95% C.I 1.04-6.45), and the only predictor of 12-month TVR was reference vessel diameter ≤2.5 mm (OR 2.16, 95% C.I 1.06-4.33). DES use was not independently predictive of lower TVR, MACE rates or mortality. Late stent thrombosis rates were similar (DES 3.2 vs. BMS 3.8%, p=0.65).

Conclusions: Drug-eluting stents are frequently used in Australia in the high-risk setting of STEMI. While target vessel revascularisation rates were moderate in this high-risk group, there was no increased mortality, reinfarction or stent thrombosis compared to bare-metal stents.