Endo Techniques, Surgery, Combos: All Have Role in CLI

By Sharon Worcester  

BOSTON -- Endovascular and surgical options both have a place in the treatment of critical limb ischemia, and approaches that combine the two are increasingly being used to optimize care, Dr. Michael S. Conte said at a symposium sponsored by the American Heart Association.

The goals of treatment in patients with critical limb ischemia (CLI) are pain relief, wound healing, preservation of a functional limb, and minimization of global risk for other major cardiovascular events.

Pain in these patients can be very difficult to treat, and most are truly suffering and grateful for any treatments that relieve pain. Wound healing is also important, because lower extremity wounds are a crucial source of ongoing morbidity, pain, and limb dysfunction, he said.

Ultimately, though, the goal is preservation of a functional limb with its associated promise for independence and maintenance of quality of life.

In patients with favorable anatomy, and especially those considered to be at high surgical risk, percutaneous revascularization strategies are being used with increasing frequency. Although many questions remain about the value of endovascular therapy, and a great deal more study is needed, it is the "new rage" in the treatment of peripheral arterial disease, said Dr. Conte, director of vascular surgery research at Brigham and Women's Hospital, Boston.

"All of us are doing it more often and more aggressively, and I think that as long we're doing it carefully and following our outcomes closely, it is a reasonable option in well-selected patients," he said.

In patients with aortoiliac disease, for example, endovascular options have assumed a primary role. Data suggest there are excellent long-term results with angioplasty and stenting in this area, particularly with Transatlantic Intersociety Consensus (TASC) A and B lesions.

However, in patients with more challenging anatomy, such as those with diffuse infrainguinal disease, and in those who have failed prior endovascular procedures, surgical bypass with vein remains the preferred method.

Based on the experience at Brigham and Women's Hospital over the past 20 years with patients undergoing lower extremity infrainguinal vein bypass, there is an increasing burden of comorbid disease in this patient population. About half present with tissue loss, two-thirds are diabetic, and many have already had coronary artery bypass.

Yet, in more than 1,600 patients, primary graft patency for infrainguinal bypass using autogenous vein is in the range of 65% at 5 years. With the use of duplex surveillance and reinterventions prophylactically, secondary patency rates increase to greater than 70% at 5 years, and limb salvage is in excess of 80% in the CLI population, he said.

Endovascular techniques in the setting of diffuse infrainguinal disease continue to be plagued by the problem of restenosis, and until this problem is solved, it will remain a major barrier to achieving more effective results with these techniques, Dr. Conte said.

Combination approaches are being used increasingly to shorten the length of graft or otherwise facilitate a simpler operation, and may provide greater efficiency in the revascularization strategy.

In some patients, primary amputation may be the best treatment option, Dr. Conte said, explaining that in those who have no good options for treatment of ongoing pain and nonhealing wounds, amputation can provide a possible return to a functional lifestyle. Patients who are nonambulatory or have extremely poor functional status also are candidates for primary amputation.

Medical therapy also is important for patients with CLI. While drug studies have generally failed to identify a direct pharmacologic approach to improve limb salvage, several studies suggest that critical cardioprotective medications are severely underutilized in this population. For example, antiplatelet therapy and statins were significantly underprescribed in at least two major studies of CLI patients.

"We have a long way to go in terms of more aggressive medical therapy in our patients with advanced [peripheral arterial disease]," Dr. Conte said.

Therapeutic angiogenesis is another treatment option that has been under intensive investigation. It shows promise, but requires a great deal more investigation, he noted.

"Direct limb revascularization really is where the focus should be in treating these patients," according to Dr. Conte.

He added that proper care of patients with critical limb ischemia requires a multidisciplinary clinical approach, as well as careful postprocedural surveillance. Often reinterventions and aggressive wound management are required to achieve durable limb salvage.