Late-term clinical outcomes with zotarolimus- and sirolimus-eluting stents. 5-year follow-up of the ENDEAVOR III (A Randomized Controlled Trial of the Medtronic Endeavor Drug [ABT-578] Eluting Coronary Stent System Versus the Cypher Sirolimus-Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions)

Abstract

Objectives: This study sought to compare late safety and efficacy outcomes following percutaneous coronary revascularization with zotarolimus-eluting stents (ZES) and sirolimus-eluting stents (SES).

Background: Despite higher late lumen loss and binary restenosis with ZES compared with SES, it is uncertain whether differences in early angiographic measures translate into more disparate late clinical events.

Methods: Clinical outcomes were prospectively evaluated through 5 years in the ENDEAVOR III (A Randomized Controlled Trial of the Medtronic Endeavor Drug [ABT-578] Eluting Coronary Stent System Versus the Cypher Sirolimus-Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions) that randomized 436 patients of relatively low anatomic and clinical risk to treatment with ZES (n = 323) or SES (n = 113) and evaluated a primary endpoint of 8-month angiographic late lumen loss.

Results: At 5 years (completeness of follow-up: 95.2%), pre-specified endpoints of all-cause mortality (5.2% vs. 13.0%, p = 0.02), myocardial infarction (1.0% vs. 4.6%, p = 0.03), and the composite event rates of cardiac death/myocardial infarction (1.3% vs. 6.5%, p = 0.009) and major adverse cardiac events (14.0% vs. 22.2%, p = 0.05) were significantly lower among patients treated with ZES. Rates of target lesion (8.1% ZES vs. 6.5% SES, p = 0.68) and target vessel revascularization were similar between treatment groups. Stent thrombosis was infrequent and similar in both groups (0.7% ZES vs. 0.9% SES, p = 1.0). Between 9 months and 5 years, progression of major adverse cardiac events was significantly more common with SES than with ZES (16.7% vs. 7.8%, p = 0.015).

Conclusions: Despite initially higher angiographic late lumen loss, rates of clinical restenosis beyond the protocol-specified angiographic follow-up period remain stable with ZES compared with the rates for SES, resulting in similar late-term efficacy. Over 5 years, significant differences in death, myocardial infarction, and composite endpoints favored treatment with ZES. (The Medtronic Endeavor III Drug Eluting Coronary Stent System Clinical Trial [ENDEAVOR III]; NCT00217256).