Four-Year Postmarket Trial Results Support Abbott Vascular's Xience V EES in Bifurcation Lesions

September 28, 2015—Four-year results from the XIENCE V USA study of real-world patients with bifurcation lesions (BIF) receiving Abbott Vascular’s Xience V everolimus-eluting stents (EES) were published online ahead of print by James B. Hermiller, MD, et al in Catheterization and Cardiovascular Interventions.

This subgroup analysis of real-world patients with BIF receiving EES demonstrated continued low rates of clinical outcomes in the BIF subgroup at 4 years with no incremental stent thrombosis increase from 2 to 4 years, concluded the investigators in Catheterization and Cardiovascular Interventions.

According to the investigators, the XIENCE V USA study has previously demonstrated safety and efficacy of the Xience V EES in a large, prospective study of a real-world, unselected patient population; however, there are limited long-term data regarding EES performance in high-risk patients with BIF. Therefore, the objective of this analysis was to evaluate the long-term safety and effectiveness of EES in patients with BIF from the XIENCE V USA study.

The Xience V USA Study was a single-arm, prospective, multicenter, real-world study of patients (n = 5,054) undergoing percutaneous coronary intervention with EES. Baseline data and clinical outcomes at 4 years were evaluated in the subgroup of patients with one or more BIF who did not undergo a staged procedure. Coprimary endpoints were Academic Research Consortium (ARC) definite/probable stent thrombosis and a composite of cardiac death and ARC-defined myocardial infarction. Endpoints were adjudicated by an independent clinical events classification group.

The investigators reported that of 4,768 patients who did not undergo a staged procedure, 511 (10.7%) patients had BIF, and 4,257 (89.3%) patients did not have BIF. Follow-up data were available in 4,459 patients (466 BIF, 3,993 non-BIF). Through binary outcome analysis, the overall definite/probable stent thrombosis rates at 1 year were higher in the BIF group (1.84% vs 0.76%; P = .03). 

However, at 4 years, the difference in cumulative rates of ARC definite/probable stent thrombosis (BIF 2.3% vs non-BIF 1.4%; P = .13) remained the same as the rates at 1 year, with no incremental definite/probable stent thrombosis in BIF patients from 2 to 4 years. The 4-year rates of composite cardiac death and myocardial infarction were 13.5% for patients with BIF versus 14.1% for patients without BIF (P = .78). At 4 years, target lesion failure (19.1% vs 18.3%; P = .66) and ischemia-driven target lesion revascularization (10.2% vs 10.1%; P = .89) were comparable between the two groups, stated the investigators in Catheterization and Cardiovascular Interventions.