The United States StuDy for EvalUating EndovasculaR TreAtments of Lesions in the Superficial Femoral Artery and Proximal Popliteal By usIng the Protégé EverfLex NitInol STent SYstem II (DURABILITY II).

OBJECTIVE

Angioplasty and stenting are options for revascularization of symptomatic femoral popliteal disease. Although angioplasty alone is effective in short lesions, longer lesions are often treated with stents. Multiple overlapping stents are expensive and may be associated with stent fracture. This trial evaluated the safety and efficacy of a single self-expanding stent up to 20 cm in length in patients with atherosclerotic disease of the superficial femoral artery (SFA) and proximal popliteal artery.

METHODS

Patients with lesions >4 cm and <18 cm were enrolled in this nonrandomized, prospective, multicenter trial that evaluated the Protégé EverFlex Self-Expanding Peripheral Stent System (Covidien, Plymouth, Minn). The study's primary end points were the 30-day major adverse event rate and duplex ultrasound-assessed patency at 1 year. These were compared with published performance goals. A preplanned analysis was conducted for the primary effectiveness end points at 1 year. Follow-up, including history, ankle-brachial index, patient-reported outcomes, duplex ultrasound assessment, and radiographs, is planned through 3 years. There was core laboratory review of angiograms, ultrasound scans, and plain radiographs. A subgroup of patients was studied with graded treadmill testing.

RESULTS

The study enrolled 287 patients (66% male; mean age, 68 years) with stenotic, restenotic, or occluded lesions of the SFA at 44 investigational sites in the United States and Europe. Systemic comorbidities included hypertension (88%), hyperlipidemia (86%), diabetes (43%), and prior SFA intervention (41%). The mean lesion length measured by the core laboratory was 89 mm. The mean normal-to-normal lesion length measured by sites was 110 mm. A total of 303 stents were implanted, and 95% of patients received a single stent. No major adverse events occurred at 30 days. At 1 year, primary outcome of duplex ultrasound stent patency was 67.7% in evaluable patients, and among 1-year secondary outcomes, the mean ankle-brachial index increased by 0.25. Walking Improvement Questionnaire scores improved in pain by 33.7, distance by 37.1, speed by 18.6, and stair climbing by 24.7. The Kaplan-Meier estimate of primary patency was 77.2%, primary assisted patency was 86.9%, and secondary patency was 87.3%. Rutherford clinical category improved in 83.5% of patients. Stent fracture rate was 0.4%. Matched absolute claudication distance was 412 feet greater and was not statistically different in this subgroup of 29 individuals.

CONCLUSIONS

The results of DURABILITY II (StuDy for EvalUating EndovasculaR TreAtments of Lesions in the Superficial Femoral Artery and Proximal Popliteal By usIng the Protégé EverfLex NitInol Stent SYstem II) suggest that a new single stent strategy is safe and effective for the treatment of long lesions of the SFA and proximal popliteal arteries at 1 year.