Comparison of Clinical and Angiographic Outcomes After Saphenous Vein Graft Angioplasty Using Coronary Versus ‘Biliary’ Tubular Slotted Stents

Abstract

Background Saphenous vein graft (SVG) angioplasty using 15-mm articulated, tubular slotted stents results in low (0% to 20%) residual diameter stenoses and infrequent (<5%) major complications. A “biliary” stent design with greater radial compressive strength, enhanced visibility, and more variable sizing (diameter and length) has been approved for noncoronary indications. A comparison of outcomes after coronary versus biliary stent placement in SVG stenoses has not been performed. The purpose of this study was to compare the angiographic and clinical results after SVG angioplasty using these two balloon-expandable, tubular slotted stent designs. Methods and Results During a 3-year period, 231 patients with 305 SVG lesions were treated using Palmaz-Schatz coronary (n=108) or biliary (n=123) stents. Cineangiograms were reviewed using qualitative morphological and quantitative angiographic methods. Time-dependent clinical outcome (freedom from death, Q-wave myocardial infarction, or the need for repeat coronary bypass surgery or SVG angioplasty) was assessed using Kaplan-Meier life-table methods. Unstable angina ( P <.001) and recent myocardial infarction ( P =.001) were present more often in patients undergoing biliary stent versus coronary stent placement. Biliary stent–treated SVG lesions were more frequently de novo ( P =.001), ostial in location ( P =.002), ≥10 mm in length ( P =.009), thrombus containing ( P =.001), and ulcerated ( P <.001) than coronary stent–treated SVG lesions. Angiographically, biliary stent–treated lesions had larger reference vessel diameter (3.43±0.59 mm versus 3.10±0.64 mm, P <.001), higher balloon-to-artery ratio (1.15±0.16 mm versus 1.07±0.19, P =.0001), and lower residual diameter stenosis (6±17% versus 14±11% in coronary stent–treated patients; P <.001). Procedural success rates were high (95%), in-hospital major complications were uncommon (<3%), and follow-up clinical outcomes were favorable (6-month event-free survival ≈80%) in both groups. Conclusions Despite frequent short-term ischemic syndromes and unfavorable lesion characteristics, both biliary and coronary cohorts have similarly favorable short-term procedural results and long-term clinical outcomes. The increased strut thickness of the biliary stent confers greater fluoroscopic visibility and radial compressive strength in exchange for decreased stent flexibility and added technical demand in stent deployment. Extreme caution is recommended with biliary stent placement in the treatment of SVG lesions as clinical results are highly operator dependent.