Final results from a postmarket registry of an iliac leg graft with a continuous, spiral nitinol stent.

Objective: To evaluate clinical outcomes from a postmarket registry of the Zenith Spiral-Z abdominal aortic aneurysm iliac leg graft with a continuous, spiral nitinol stent that was designed for improved conformability, kink, and migration resistance.

Methods: This prospective, multicenter registry was designed to evaluate physician-reported outcomes of the Spiral-Z leg graft in up to 600 patients who underwent endovascular repair of abdominal aortic or aortoiliac aneurysms at up to 30 investigative sites in the United States and Canada. Study outcomes were focused on iliac limb occlusion, limb-related reintervention, limb-related endoleak, component separation, and device integrity. Short-term data were collected during an interval of 1 to 6 months, with longer term data collected at 12 months.

Results: Between March 2012 and March 2015, 599 patients (mean age 74 ± 8 years; 87% male; 26% with aortoiliac aneurysm) were treated, with Spiral-Z iliac leg grafts placed in 564 left iliac arteries and 559 right iliac arteries. The mean iliac inner diameters (both left and right) were 9 ± 3 mm; moderate/severe occlusive disease, calcification, and vessel tortuosity were present in 14%, 25%, and 36% and 15%, 25%, and 34% of the left and right iliac arteries, respectively. Iliac artery adjunctive procedures (iliac artery angioplasty and/or stent placement) were performed intraoperatively in 112 patients (19%; bilateral in 52 patients). Mortality within 30 days was 1.7% (10/599); cumulative mortality at 1 year was 6.2% (37/599). There were no aortic ruptures and only one open conversion (0.2%). Limb occlusions occurred in 11 of 599 patients (2%; 3 within 30 days and 8 after 30 days, all unilateral, none had received procedural iliac artery adjuncts at implantation); of these, 7 patients underwent reinterventions. Other limb-related reinterventions were performed on eight patients for nonocclusive kink, compression, or thrombus (six within 30 days and three after 30 days). In total, 13 patients (2%) underwent 15 limb-related reinterventions (7 for occlusions and 8 for nonocclusive causes). In one patient, a distal type I endoleak and device migration (>10 mm) involving a right iliac leg was noted at the 12-month follow-up visit. No other limb-related endoleak, migration, component separation, or stent fracture was reported during a mean follow-up of 11 ± 6 months.

Conclusions: The Spiral-Z leg graft demonstrated excellent patency and required infrequent limb-related reinterventions in routine clinical care in a postmarket registry.