Outcomes in Patients Treated With Thin-Strut, Very Thin-Strut, or Ultrathin-Strut Drug-Eluting Stents in Small Coronary Vessels: A Prespecified Analysis of the Randomized BIO-RESORT Trial

Abstract

Importance: Stenting small-vessel lesions has an increased adverse cardiovascular event risk. Very thin-strut or ultrathin-strut drug-eluting stents might reduce this risk, but data are scarce.

Objective: To assess the outcome of all-comer patients with small coronary vessel lesions treated with 3 dissimilar types of drug-eluting stents.

Design: This is a prespecified substudy of the Comparison of Biodegradable Polymer and Durable Polymer Drug-eluting Stents in an All Comers Population (BIO-RESORT) trial, an investigator-initiated, randomized, patient-blinded comparative clinical drug-eluting stent trial. Patients treated with ultrathin-strut sirolimus-eluting stents, very thin-strut everolimus-eluting stents, or previous-generation thin-strut zotarolimus-eluting stents were enrolled from December 2012 to August 2015. This multicenter trial was conducted in 4 Dutch centers for cardiac intervention. Of all 3514 all-comer BIO-RESORT participants, 1506 patients with treatment in at least 1 small-vessel lesion (reference vessel <2.5 mm) were included. Data were analyzed between September 2018 and February 2019.

Main outcomes and measures: Target lesion failure at 3-year follow-up, a composite of cardiac death, target vessel-related myocardial infarction, or target lesion revascularization, analyzed by Kaplan-Meier methods.

Results: In 1452 of 1506 participants (96.4%) (1057 men [70.2%]; 449 women [29.8%]; mean [SD] age, 64.3 [10.4] years), follow-up was available. Target lesion failure occurred in 36 of 525 patients (7.0%) treated with sirolimus-eluting stents, 46 of 496 (9.5%) with everolimus-eluting stents, and 48 of 485 (10.0%) with zotarolimus-eluting stents (sirolimus-eluting vs zotarolimus-eluting hazard ratio [HR], 0.68; 95% CI, 0.44-1.05; P = .08; everolimus-eluting vs zotarolimus-eluting HR, 0.93; 95% CI, 0.62-1.39; P = .72). There was a difference in target lesion revascularizations between sirolimus-eluting and zotarolimus-eluting stents (2.1% vs 5.3%; HR, 0.40; 95% CI, 0.20-0.81; P = .009) that emerged after the first year of follow-up (1.0% vs 3.7%; P = .006); multivariate analysis showed that sirolimus-eluting stent implantation was independently associated with a lower target lesion revascularization rate at 3-year follow-up (adjusted HR, 0.42; 95% CI, 0.20-0.85; P = .02). In the everolimus-eluting stents, the revascularization rate was 4.0% (vs zotarolimus-eluting, HR, 0.74; 95% CI, 0.41-1.34; P = .31). There was no significant between-stent difference in cardiac death, target vessel myocardial infarction, or stent thrombosis.

Conclusions and relevance: Patients stented in small coronary vessels experienced fewer repeated revascularizations if treated with ultrathin-strut sirolimus-eluting stents vs previous generation thin strut zotarolimus-eluting stents. Further research is required to evaluate the potential effect of particularly thin stent struts.

Trial registration: ClinicalTrials.gov identifier: NCT01674803.

Figure 1.. Trial Profile

Information on the number of patients treated with drug-eluting stents during the period of study enrollment is given irrespective of whether these patients fulfilled the inclusion and exclusion criteria because we do not have reliable data on the total number of eligible patients. EES indicates everolimus-eluting stent; SES, sirolimus-eluting stent; ZES, zotarolimus-eluting stent.

Figure 2.. Kaplan-Meier Cumulative Event Curves for Target Lesion Failure and Its Individual Components at 3-Year Follow-up

Target lesion failure (A), a composite of cardiac death (B), target vessel-related myocardial infarction (C), or clinically indicated target lesion revascularization (D). HR indicates hazard ratio.

Figure 3.. Landmark Analyses at 1 Year for Target Lesion Failure (TLF) and Clinically Indicated Target Lesion Revascularization (TLR)

TLF until 2 years (A) and 3 years (C) of follow-up; TLR until 2 years (B) and 3 years (D) of follow-up. HR indicates hazard ratio.