Everolimus-eluting stent versus bare-metal stent in ST-segment elevation myocardial infarction (EXAMINATION): 1 year results of a randomised controlled trial

Abstract

Background: Everolimus-eluting stent (EES) reduces the risk of restenosis in elective percutaneous coronary intervention. However, the use of drug-eluting stent in patients with ST-segment elevation myocardial infarction (STEMI) is still controversial. Data regarding the performance of second-generation EES in this setting are scarce. We report the 1-year result of the EXAMINATION (clinical Evaluation of the Xience-V stent in Acute Myocardial INfArcTION) trial, comparing EES with bare-metal stents (BMS) in patients with STEMI.

Methods: This multicentre, prospective, randomised, all-comer controlled trial was done in 12 medical centres in three countries. Between Dec 31, 2008, and May 15, 2010, we recruited patients with STEMI up to 48 h after the onset of symptoms requiring emergent percutaneous coronary intervention. Patients were randomly assigned (ratio 1:1) to receive EES or BMS. Randomisation was in blocks of four or six patients, stratified by centre and centralised by telephone. Patients were masked to treatment. The primary endpoint was the patient-oriented combined endpoint of all-cause death, any recurrent myocardial infarction, and any revascularisation at 1 year and was analysed by intention to treat. The secondary endpoints of the study included the device-oriented combined endpoint of cardiac death, target vessel myocardial infarction or target lesion revascularisation, and rates of all cause or cardiac death, recurrent myocardial infarction, target lesion or target vessel revascularisation, stent thrombosis, device and procedure success, and major and minor bleeding. This trial is registered with ClinicalTrials.gov, number NCT00828087.

Findings: Of the 1504 patients randomised, 1498 patients were randomly assigned to receive EES (n=751) or BMS (n=747). The primary endpoint was similar in both groups (89 [11·9%] of 751 patients in the EES group vs 106 [14·2%] of 747 patients in the BMS group; difference -2·34 [95% CI -5·75 to 1·07]; p=0·19). Device-oriented endpoint (44 [5·9%] in the EES group vs 63 [8·4%] in the BMS group; difference -2·57 [95% CI -5·18 to 0·03]; p=0·05) did not differ between groups, although rates of target lesion and vessel revascularisation were significantly lower in the EES group (16 [2·1%] vs 37 [5·0%], p=0·003, and 28 [3·7%] vs 51 [6·8%], p=0·0077, respectively). Rates of all cause (26 [3·5%] for EES vs 26 [3·5%] for BMS, p=1·00) or cardiac death (24 [3·2%] for EES vs 21 [2·8%] for BMS, p=0·76) or myocardial infarction (10 [1·3%] vs 15 [2·0%], p=0·32) did not differ between groups. Stent thrombosis rates were significantly lower in the EES group (4 [0·5%] patients with definite stent thrombosis in the EES group vs 14 [1·9%] in the BMS group and seven [0·9%] patients with definite or probable stent thrombosis in the EES group vs 19 [2·5%] in the BMS group, both p=0·019). Although device success rate was similar between groups, procedure success rate was significantly higher in the EES group (731 [97·5%] vs 705 [94·6%]; p=0·0050). Finally, Bleeding rates at 1 year were comparable between groups (29 [3·9%] patients in the EES group vs 39 [5·2%] in the BMS group; p=0·19).

Interpretation: The use of EES compared with BMS in the setting of STEMI did not lower the patient-oriented endpoint. However, at the stent level both rates of target lesion revascularisation and stent thrombosis were reduced in recipients of EES.

Funding: Spanish Heart Foundation.