Safety and superior effectiveness over two years in femoropopliteal region with drug-eluting stents

Original title: Sustained safety and effectiveness of paclitaxel-eluting stents for femoropopliteal lesions: two-year follow-up from the Zilver PTX randomized and single-arm clinical studies. Reference: Michael D. Dake et al. J Am Coll Cardiol 2013. Article in press.

Studies with long-term monitoring showed mainly the limited permeability of balloon angioplasty, especially over challenging injuries such as total occlusions or very long lesions. Stents improve the initial result but the long-term benefit remains sub-optimal showing an annual permeability of between 60% and 80%, particularly for long lesions. 

The aim of this study was to test the efficacy of self-expandable nitinol Zilver PTX paclitaxel eluting stents, (PTX Zilver, Cook Medical, Bloomington, IN), over the femoropopliteal region. The study randomized 474 patients to Zilver PTX versus balloon, another 120 patients with acute failure of balloon angioplasty were randomized as a secondary group to Zilver PTX versus a conventional self-expanding stent and finally the study had a registry of 787 patients treated primarily with Zilver PTX. In total some 1,084 patients received a paclitaxel-eluting stent. Major events were considered: death, amputation and surgical or percutaneous revascularization justified by the clinic. The event-free survival was defined as the absence of major events listed above plus the absence of worsening Rutherford classification. 

The average lesion length was 65 ± 40 mm in randomized patients and 99.5 ± 82.1 mm for patients in the register. After two years, event-free survival was 86.6% for the Zilver PTX branch versus 77.9% for the balloon branch, (p =0.02). For registry patients event-free survival was 79.3%. After two years, primary patency with Zilver PTX was 74.8% and was higher than the 53.4% of balloon angioplasty, (p <0.01), and also higher than 57.3% of balloon angioplasty requiring a provisional conventional stent due to a suboptimal result, (p <0.01).

Conclusion: 

After two years the Zilver PTX stent showed safety, permeability, clinical benefit and no adverse events related to paclitaxel both in de novo lesions as well as by restenosis in the femoropopliteal region.

Editorial Comment: 

Injuries over 140 mm were excluded which is a major limitation of the work given the frequently extensive lesions in the superficial femoral artery.There was a similar improvement regarding baseline as Rutherford class, ankle / brachial index and walking distance from the Zilver PTX stent and balloon angioplasty. The detail to keep in mind is that the balloon needs more reinterventions in order to get the same clinical result. No benefit was observed with dual antiplatelet therapy beyond 3 months, suggesting that coronary territory information should not be extrapolated to the femoropopliteal region. The study we are waiting for, is the drug-eluting stent versus drug eluting balloon and provisional conventional stent. 

SOLACI.ORG

*

Top