Outcomes of the Japanese multicenter Viabahn trial of endovascular stent grafting for superficial femoral artery lesions

Abstract

Objective: The objective of this study was to assess 1-year safety, efficacy, and invasiveness outcomes of endovascular stent grafting of symptomatic long lesions (≥10 cm) in the superficial femoral artery (SFA) as a substitute for above-knee open bypass surgery.

Methods: This prospective, multicenter (15 hospitals) study assessed heparin-coated stent grafts for the treatment of long SFA lesions in Japanese subjects with peripheral arterial disease. Inclusion criteria were Rutherford category 2 to 5 symptoms (grade 5 without active infection), ankle-brachial index ≤0.9, and color flow duplex ultrasound-assessed SFA lesions with cumulative length ≥10 cm and ≥50% stenosis. Main efficacy and safety outcomes were primary assisted patency and adverse events, respectively. Secondary outcomes included primary patency using the surgical bypass definition, that is, blood flow through a device without requiring target lesion revascularization (TLR) to maintain or to restore flow. For comparison with prior endovascular studies, primary patency-interventional was defined as peak systolic velocity ratio <2.5 without TLR in treated lesions. Other outcomes included freedom from TLR and Vascular Quality of Life questionnaire scoring. General anesthesia avoidance and hospitalization duration were compared with historical data from 68 consecutive patients (n = 51 Rutherford 2/3 claudicants and 17 Rutherford 4/5 subjects) who underwent above-knee bypass surgery at study sites between 2002 and 2012 and met study enrollment criteria.

Results: Of 103 enrollees (74.2 ± 7.0 years old; 17.5% female; 97.1% claudicants), 100 subjects were evaluated through postoperative 12 months. Average lesion length was 21.8 ± 5.8 cm, and 65.7% were totally occluded. The whole-cohort Kaplan-Meier estimated primary assisted patency rate was 94.1% (95% confidence interval [CI], 87.3%-97.3%) at 12 months. The primary patency-surgical rate was 92.1% (95% CI, 84.8%-96.0%), the primary patency-interventional rate was 88.1% (95% CI, 80.0%-93.1%), and freedom from TLR was 93.1% (95% CI, 86.1%-96.7%). Mean ankle-brachial index increased from 0.64 ± 0.12 to 0.98 ± 0.12 at 1 month after intervention and 0.94 ± 0 .17 at 12 months (P < .0001 at both follow-ups). Target vessel revascularization, major amputation, or death did not occur through postoperative 30 days. No life- or limb-threatening intraoperative or perioperative adverse events and no acute limb ischemia cases were observed during follow-up. Vascular Quality of Life questionnaire score increased from 58.6% ± 15.7% to 72.9% ± 18.6% at 12 months (P < .0001). No stent fractures were detected. No stent graft participant required general anesthesia, and median postoperative hospital stay was 2.0 days (mean, 3.4 ± 2.9 days) in the Viabahn (W. L. Gore & Associates, Flagstaff, Ariz) claudicant subgroup, values that were significantly lower than the 76.5% general anesthesia rate (P < .0001) and 11.0 days median hospitalization stay (mean, 12.7 ± 5.3 days; P < .0001) in the 51 open bypass claudicant subjects.

Conclusions: Stent grafting appears to be a safe and less invasive alternative to above-knee bypass surgery, providing 88% to 92% primary patency at 12 months in long, complex lesions.

Trial registration: ClinicalTrials.gov NCT01575808.