Revascularization of a specific angiosome for limb salvage: does the target artery matter?
Ischemic wounds of the lower extremity can fail to heal despite successful revascularization. The foot can be divided into six anatomic regions (angiosomes) fed by distinct source arteries arising from the posterior tibial (three), anterior tibial (one), and peroneal (two) arteries. This study investigated whether bypass to the artery directly feeding the ischemic angiosome had an impact on wound healing and limb salvage. Retrospective analysis was performed for 52 nonhealing lower extremity wounds (48 patients) requiring tibial bypass over a 2-year period. Preoperative arteriograms were reviewed to determine arterial anatomy relative to each wound's specific angiosome and bypass anatomy. Patients were divided into two groups; direct revascularization (DR, bypass to the artery directly feeding the ischemic angiosome) or indirect revascularization (IR, bypass unrelated to the ischemic angiosome). Wound outcome was analyzed with regard to the endpoints of complete healing, amputation, or death unrelated to the wound. Time to healing was also noted for healed wounds. Based on preoperative arteriography, 51% (n = 27) of the wounds received DR to the ischemic angiosome, while 49% (n = 25) underwent IR. There were no statistically significant differences in the comorbidities of the two groups. Revascularization was via tibial bypass using the saphenous vein (n = 34, 65%) or polytetrafluoroethylene with a distal vein patch (n = 18, 35%). Bypasses were performed to the anterior tibial (n = 22, 42%), posterior tibial (n = 17, 33%), or peroneal (n = 13, 25%) arteries based on the surgeon's judgment. One bypass failed in the perioperative period and was excluded from the analysis. The remaining bypasses were patent at the time of wound analysis. Due to a 17% mortality rate during follow-up, 43 wounds were available for endpoint analysis. This analysis demonstrated that 77% of wounds (n = 33) progressed to complete healing and 23% of wounds (n = 10) failed to heal with resultant amputation. In the DR group, there was 91% healing with a 9% amputation rate. In the IR group, there was 62% healing with a 38% amputation rate (p = 0.03). In those wounds that did heal, total time to healing was not significantly different--DR 162.4 days versus IR 159.8 days (p = 0.95). Revascularization plays a crucial role in the treatment of ischemic lower extremity wounds. We believe that direct revascularization of the angiosome specific to the anatomy of the wound leads to a higher rate of healing and limb salvage. Although many factors must be considered in choosing the target artery for revascularization, consideration should be given to revascularization of the artery directly feeding the ischemic angiosome.