Assessing Vascular Surgery Options In Patients With PAD
Without effective intervention, PAD can lead to chronic limb ischemia, a condition characterized by intermittent claudication, poor healing capability in the presence of a wound and eventual amputation.10 Traditionally, vascular surgeons have treated PAD with techniques such as open surgical bypass, surgical endarterectomy, balloon angioplasty and stent placement. While each of these procedures has its advantages in a given patient population, each also has a fair share of shortcomings that warrant the use of a better approach in the management of PAD.
Open surgical bypass produces quite favorable long-term clinical results for the treatment of lower limb PAD.11 However, one must consider the invasiveness of such a procedure in the face of the comorbidities that often affect patients with PAD. Complications encountered in open bypass include a prolonged hospital stay, the need for rehabilitation, increased wound complications (ischemic or infectious wounds and surgical dehiscence), prolonged healing time (> three months) and a delayed return to normal activity.12
Even though the mortality rate associated with the bypass procedure itself is not very high, the morbidity linked to bypass often disqualifies certain high-risk patients (those patients with multiple comorbidities) from undergoing the procedure. Goshima, Mills and Hughes reported a revisionary procedure rate of 49.3 percent (112 out of 318 patients) within six months of patients undergoing a bypass.12
Endarterectomy, the surgical removal of plaque from a narrowed artery, is an effective method for the removal of well-defined atheromatous plaque from the vessel lumen. Although this is less invasive than open surgical bypass, the procedure does not lend itself well to the type of ill defined, dispersive lesions frequently encountered in the lower extremity.13 Endarterectomy does remain a viable option for occlusion of upper extremity vessels, such as the carotid artery. While balloon angioplasty has long been the mainstay in minimally invasive treatment of PAD, it is plagued by poor long-term patency rates and an up to 60 percent rate of vessel dissection, requiring stent placement.14 The primary reason for the failure of angioplasty is restenosis (defined as a 50 percent or greater lumen loss at a two-year follow-up), which is caused by intimal barotraumas, hyperplasia and plaque recoil.13,15 Certain modifications to angioplasty have produced procedures such as brachytherapy, cryoplasty and cutting balloons to minimize restenosis rates. These procedures have yet to show significant improvements on the traditional angioplasty in order for them gain widespread clinical use.16
The efficacy of stent placement is limited due to plaque mobilization or shifting, which can lead to restenosis in another location. This is especially a problem in ostial areas and areas of vessel bifurcation.17 A 2005 study of stent fractures after stenting in the femoropopliteal area showed a fracture rate of 37.2 percent, leading to restenosis in 32.8 percent and total reocclusion in 34.4 percent of these cases.18