Six-month pivotal results of tack optimized balloon angioplasty using the Tack Endovascular System in below-the-knee arteries

Abstract

Objective: No vascular implant is commercially available in the United States to treat post-angioplasty dissections in below-the-knee (BTK) arteries. The Tack Endovascular System (Intact Vascular, Wayne, Pa) is purpose-built to repair postpercutaneous transluminal angioplasty (PTA) BTK dissections. A trial was conducted to investigate the safety and efficacy of the first-of-a-kind implantable BTK device to treat post-PTA dissections in the setting of critical limb ischemia.

Methods: The present prospective, single-arm, multicenter study evaluated the Tack Endovascular System for treating post-PTA dissections in the mid/distal popliteal, tibial, and peroneal arteries. The primary safety endpoint was major adverse limb events (MALE) plus perioperative death (POD), assessed at 30 days after the index procedure. The primary efficacy endpoint was a composite of MALE at 6 months and POD. The unpowered secondary endpoint was primary patency at 6 months. With no available on-label comparator, the primary endpoints of the present trial were determined using objective performance goals from a systematic literature search. The secondary endpoints included Tacked segment patency and target limb salvage at 6 months. The 6-month results are reported.

Results: Of the 233 patients enrolled, 117 (50.2%) had Rutherford class 5 and 78 (33.5%) had Rutherford class 4. A total of 341 post-PTA dissections were treated. Each patient received at least one Tack implant, and 100% of the dissections resolved according to the angiographic core laboratory findings. The primary safety and efficacy endpoints were both met. The rate of MALE plus POD at 30 days was 1.3% (3 of 228) and freedom from MALE at 6 months plus POD at 30 days was 95.6% (196 of 205). The 6-month Tacked segment patency was 82.1% (247 of 301) and target limb salvage was 98.5% (202 of 205). The Kaplan-Meier freedom from clinically driven target lesion revascularization and amputation-free survival at 6 months was 92.0% and 95.7%, respectively. Rutherford improvement was reported in 79.4% (158 of 199). Most (90 of 122; 73.8%) preexisting wounds had healed or were improving.

Conclusions: The Tack Endovascular System is safe and effective for treating post-PTA BTK dissections through 6 months, with favorable rates of MALE plus POD, patency, clinically driven target lesion revascularization, limb salvage, and wound healing.

Keywords: Balloon angioplasty; Critical limb ischemia; Dissection; Infrapopliteal arteries; Peripheral artery disease.