Treatment Options Remain Limited For SFA In-Stent Restenosis

By Sharon Worcester  

BOSTON -- The problem of superficial femoral artery in-stent restenosis is common and not easily solved, Dr. Ronald Waksman said at a symposium sponsored by the American Heart Association.

About a third of patients develop in-stent restenosis. And though potential treatments exist, the data supporting their use in this location are sorely lacking, said Dr. Waksman of the MedStar Research Institute, Washington.

"Don't be seduced by all these technologies. ... Think twice before you put a stent in," he advised.

A number of approaches--such as balloon angioplasty, laser angioplasty, sonotherapy, and directional and rotational atherectomy--consistently failed as treatments for coronary artery in-stent restenosis, with about a 50% recurrence rate.

A more promising approach is brachytherapy, which works well in the coronary arteries, and is, in fact, the only approved therapy for coronary artery in-stent restenosis. There is some evidence that it may be helpful in the superficial femoral artery, but there are limitations. The systems are complex and not widely available, and patients often have to be sent to a radiation oncologist for treatment, Dr. Waksman explained.

Other approaches deserve further study. Limited data suggest that endoluminal grafting, cryotherapy, systemic therapy, photodynamic therapy, and gene therapy may have promise. Systemic therapy with rapamycin and high-dose steroids for inflammation has been shown to have some beneficial effects on restenosis, and photodynamic therapy appears capable of obliterating neointimal formations. With the right dose, these treatments could have potential, Dr. Waksman said.

Based on current evidence, however, the "stent concept is not working well in superficial femoral arteries," he said, adding: "This is the motivation to go to biodegradable stents." Early results of studies of bioabsorbable stents are impressive, and offer the best hope for treatment, particularly if a drug to prevent restenosis is added, he concluded.

Dr. Omaida Velazquez, assistant professor of surgery, division of vascular surgery, Hospital of the University of Pennsylvania, Philadelphia, commented on this article: "The problem of critical limb ischemia (CLI) introduces yet another dimension to the subtle and complex clinical judgments required to determine if a patient may benefit from stenting of the SFA. In patients with CLI resulting in wounds, gangrene, infection, or rest pain, all available data indicate that limb salvage rates after SFA interventions are much higher than mid- and long-term term patency rates.

"That is, the acute limb threatening situation may be overcome by relatively short, yet adequate patency. This must be kept in mind since many of the endovascular techniques available for angioplasty or recannalizing the SFA may have an occasional obligatory need for stenting in order to achieve intraprocedural technical success.

"These new technologies vary widely in their ability to address each different extent of disease from short/focal lesions to long/diffuse lesions, to chronic occlusions, to multifocal and multilevel disease. Given the complete absence of head-to-head randomized prospective studies, an in-depth familiarity with the strengths and limitations of each of these new modalities is essential for achieving an optimal treatment algorithm that incorporates the old and the new technologies and ideally matches the tool to the disease extent.

"Until we learn more about these new treatment options, it is important to avoid the trap of recommending only the tool most familiar, most accessible, or most economical," Dr. Velazquez added.