Five-year outcome after implantation of zotarolimus- and everolimus-eluting stents in randomized trial participants and nonenrolled eligible patients: A secondary analysis of a randomized clinical trial

IMPORTANCE: Long-term follow-up after a clinical trial of 2 often-used, newer-generation drug-eluting stents (DESs) in a broad patient population is of interest. Comprehensive long-term outcome of eligible nonenrolled patients has never been reported.

OBJECTIVE: To assess 5-year safety and efficacy of 2 newer-generation DESs in randomized participants with non–ST-elevation acute coronary syndromes or stable angina and to evaluate long-term outcomes of nonenrolled eligible patients treated with the same DESs.

DESIGN, SETTING, AND PARTICIPANTS: The TWENTE (Real-World Endeavor Resolute vs Xience V Drug-Eluting Stent Study in Twente) trial is an investigator-initiated, patient-blinded, randomized, comparative DES trial that enrolled patients from June 18, 2008, to August 26, 2010. Most patients had non–ST-elevation acute coronary syndromes and complex lesions. Of all 1709 eligible patients, 1391 (81.4%) were treated in the TWENTE trial with zotarolimus-eluting (ZES, n = 697) or everolimus-eluting (EES, n = 694) cobalt-chromium stents. The remaining 318 eligible patients (18.6%) were not enrolled but underwent nonrandomized treatment with the same DESs. Data were analyzed from August 26, 2015, to October 11, 2016. Event rates (percentages) were derived from log-rank analysis and may differ from straightforward calculation (nominator/denominator). The 5-year follow-up of the TWENTE participants was prespecified in the trial protocol; that of the nonenrolled participants was ad hoc.

MAIN OUTCOMES AND MEASURES: Target vessel failure (TVF), a composite of cardiac death, target vessel–related myocardial infarction, or target vessel revascularization.

RESULTS: Of 1709 eligible participants, 1233 (72.1%) were men, 476 (27.9%) were women, and mean (SD) age was 64.6 (10.6) years. Among the 1370 of 1391 TWENTE trial participants (98.5% follow-up), TVF was similar between those in the ZES (16.1%) and EES (18.1%) groups (P = .36). Stent thrombosis rates were low: definite (7 of 697 [1.0%] vs 4 of 694 [0.6%]; P = .37) and occurred after more than 1 year in 3 (0.4%) with ZES vs 4 (0.6%) with EES (P = .69). The 318 nonenrolled eligible patients (308 patients [96.9%] of whom were followed up) were older and had more advanced disease than trial participants. Their TVF rate was higher than that of trial participants (71 of 318 [23.3%] vs 233 of 1391 [17.1%]; P = .02), which partly reflects a difference in cardiac mortality (23 of 318 [7.7%] vs 60 of 1391 [4.5%]; P = .03). Similar 5-year rates were found for myocardial infarction (91 of 1391 [6.7%] vs 22 of 318 [7.2%]; P = .80) and target vessel revascularization (129 of 1391 [9.7%] vs 34 of 318 [11.4%]; P = .36) between trial participants and nonenrolled eligible patients. In all eligible patients (ie, trial participants plus nonenrolled eligible patients), the TVF rate was only slightly higher than in trial participants only (18.3% vs 17.1%).

CONCLUSIONS AND RELEVANCE: Long-term outcome data from nonenrolled eligible patients support the validity of the TWENTE trial findings and present, with the trial, a strong case for the long-term safety and efficacy of the newer-generation DESs used.

TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01066650.