SLR - May 2012 - Gabriel V. Gambardella
Reference: J Vasc Surg. 2011 Dec. 29 [Epub ahead of print]
Scientific Literature Review
Reviewed by: Gabriel V. Gambardella, DPM
Residency Program: Yale-New Haven Hospital
Podiatric Relevance:
Critical limb ischemia is generally manifested in extensive occlusive atherosclerotic disease at the tibio-peroneal trunk. Because the pedal arteries are relatively unharmed during this disease process, the dorsalis pedis and common plantar arteries, along with their branches, can be utilized for revascularization as a last attempt for limb preservation. The podiatric physician has the opportunity to be the first physician to identify this disease process in a patient, and can obtain the necessary consultations. Furthermore, together with vascular surgeons and the appropriate intervention to optimize distal perfusion, podiatric surgeons can play a pivotal role in the limb preservation process.
Methods:
137 inframalleolar bypass graft surgeries were performed between January 1991 and February 2010. Sixty-four percent of the patients were male and 36 percent of the patients were female, with diabetes mellitus and hypertension each being present in 68 percent of patients. All patients were diagnosed with critical limb ischemia, defined by criteria given by the Rutherford classification IV, V, and VI, which include rest pain, ischemic ulceration not exceeding an ulcer of the digits of the foot (minor tissue loss), and severe ischemic ulcers or frank gangrene (major tissue loss), respectively. Thity-six percent of the patients were current smokers, 16 percent had coronary artery disease (CAD), 8 percent had congestive heart failure (CHF), and 8 percent had chronic kidney failure not requiring dialysis.
Atherosclerotic disease in most patients involved the tibial and peroneal vessels, and diagnostic studies pre-operatively revealed patent pedal branches for intra-operative anastamosis. The limbs that were deemed salvageable demonstrated ischemic lesions not beyond the metatarsal level, or superficial calcaneus level, without extensive tissue loss. Autogenous conduits were utilized for the bypass graft. Those who were considered high-risk for surgery by a cardiologist were not eligible for the revascularization, and primary amputation was recommended. Pre-operatively, mean ankle-brachial index (ABI) was 0.39.
Results:
Sixty-eight percent of the bypasses performed were short-length grafts with the below-knee popliteal artery as the main inflow site in 12 and the medial plantar artery as the main outflow site in 13, while the remainder of outflow sites included the lateral tarsal and lateral plantar arteries. Mean follow-up was 46.3 months. The primary failure rate was 16 percent, with four early graft occlusions occurring within 30 days of the revascularization. Limb salvage rates were 81.7 percent and 69 percent at one and three years after surgery, respectively. Two out of the nine major amputations necessary were above knee. After bypass, 10 patients required minor amputations restricted to the forefoot. Of the 65.4 percent of patients who survived at three-years post-operatively, 67 percent of them preserved ambulatory function, 54 percent were able to maintain their activities of daily living, and 36 percent were dependent on a caregiver.
There was a 24 percent complication rate in the early post-operative period, including acute myocardial ischemia (2), superficial wound infection (4), and pneumonia (3). Two patients died of pneumonia within 30 days of surgery, making the surgical mortality rate 8 percent. Univariate analysis demonstrated that no variable was associated with a worse outcome in terms of secondary patency, limb salvage, and survival, including age, diabetes, hypertension, smoking, gender, and prior bypass surgery.
Conclusions:
The three-year limb salvage rate was 69 percent, and is considered satisfactory. This technique plays a role in critical limb ischemia and can be used as an alternative to limb salvage when endovascular reconstruction fails.