Chief Medical Editor's Page
Defeating SFA Disease
Despite all of the advances that have been made in the field of endovascular interventions during the past 25 years, progress in the treatment of disease in the superficial femoral (SFA) and popliteal arteries has been elusive. Much of this lack of progress can be attributed to the nature of the disease we are trying to treat. The femoropopliteal segment is probably the body’s most heavily diseased vascular bed; occlusion predominates over stenosis, and diffuse disease and heavy calcification are common. In addition, there is often coexistent disease of the below-knee run-off vessels, which negatively impacts the long-term success of our interventions. The distal SFA passes through the adductor canal, where a variety of mechanical forces are applied to the artery that can both predispose to the development of atherosclerosis but also influence the results of treatments for this atherosclerosis. The recent finding that nitinol stents implanted in the distal SFA are subject to stent-wire fractures has brought further attention to the complex nature of the forces that are applied to the vessel in this region.
Historically, the results of femoropopliteal balloon angioplasty have been suboptimal. Patency rates have been reported to be 50% to 60% at 3 to 5 years after successful PTA. Several factors have been identified that affect the long-term results of femoropopliteal PTA. These include diabetes, the length of the lesion, the status of the distal run-off vessels, and the presence of occlusion versus stenosis. The results of PTA for long occlusions or diffuse disease in the setting of diabetes and/or poor run-off are particularly unsatisfactory. One-year patency rates have been reported to be as low as 20%. This led many vascular specialists to abandon PTA as a means of treating long-segment femoropopliteal disease. The favorable results of stenting in the iliac arteries held promise that stents might be the answer for SFA disease. The early experience with first-generation stents, however, was disappointing. In the Wallstent Registry, 1-year patency rates after stenting were only 61% and decreased to 49% after 2 years. The results with stenting for long-segment disease were even more dismal.
With this issue of Endovascular Today, we see that progress is finally being made in the battle against femoropopliteal disease. Gary Ansel, MD, and Mark Mewissen, MD, give us an update on the encouraging results being seen with some of the newer nitinol stents for this application. Giancarlo Biamino, MD, the world’s foremost expert on the use of peripheral excimer laser angioplasty, makes the case for laser debulking of long SFA occlusions as a means of improving long-term patency and minimizing the need for stents.
The encouraging results of several important antirestenosis therapies will also be reviewed. Brachytherapy, proven effective for the treatment of coronary in-stent restenosis, is currently undergoing evaluation for the treatment of de novo and restenotic femoropopliteal lesions. Cryotherapy is a novel approach to the treatment of vascular disease that uses a cold balloon to simultaneously dilate and cool the vessel. A prospective, multicenter registry utilizing the CryoVascular PolarCath (Los Gatos, CA) balloon for the treatment of femoropopliteal disease was recently completed and the early results are very promising.
As you can see, there is much to talk about, and many reasons for optimism. I hope you find this issue informative and exciting.