SLR - August 2017 - Elizabeth A. Sanders

Differential Impact of Bypass Surgery and Angioplasty on Angiosome-Targeted Infrapopliteal Revascularization

Reference: Spillerova K, Biancari F, Leppäniemi A, Albäck A, Söderström M, Venermo M. Differential Impact of Bypass Surgery and Angioplasty on Angiosome-Targeted Infrapopliteal Revascularization. Eur J Vasc Endovasc Surg. 2015 Apr; 49(4):412–419.

Scientific Literature Review

Reviewed By: Elizabeth A. Sanders, DPM
Residency Program: Boston University Medical Center; Boston, MA

Podiatric Relevance: Applying the concept of angiosomes in critical limb ischemia (CLI) and lower-extremity tissue loss has become an interesting topic in treatment planning and clinical research. Podiatric surgical planning and wound care management require a thorough understanding of pedal vascular supply, especially when revascularization is required. Complex vasculopathic patients require an organized team approach and planning amid the foot and ankle surgeon and vascular surgeon, including other specialties as well. It is essential to understand how different strategies of revascularization, especially of involved angiosomal regions, will affect wound healing and limb salvage outcome.

Methods: A retrospective study of 744 patients seen between January 2010 and July 2013 with critical limb ischemia and tissue loss graded Fontaine IV were reviewed. A review of patient records was performed using a prospectively collected database. In patients who underwent endovascular treatment involving percutaneous transluminal angioplasty, angiograms prior to and after revascularization were evaluated to determine whether the procedure had been angiosome-targeted (recanalization to the involved angiosomal artery) or not. In patients who underwent surgical bypass, preoperative MRI angiograms were reviewed. Statistical analysis was performed; differences in outcomes after bypass surgery versus angioplasty were adjusted by estimating a propensity score.

Results: Angiosome-targeted revascularization, open bypass surgery, C-reactive protein (CRP) >10 mg/dL and fewer angiosomes affected were associated with improved pedal wound healing. When results are adjusted for C-reactive protein and number of affected angiosomes via a propensity score, angiosome-targeted bypass surgery was associated with a significantly higher rate of wound healing in comparison to nonangiosome-targeted angioplasty. Impressively, nonangiosome-targeted bypass surgery obtained better wound healing rates than angioplasty independently of the angiosome-oriented strategy. Independent predictors of major amputation include a greater number of affected angiosomes, atrial fibrillation, C-reactive protein >10 mg/dL, Chronic Kidney Disease stage 5 and nonangiosome-targeted revascularization. Among patients who underwent angiosome-targeted revascularization, bypass surgery was associated with significantly improved wound healing rate but similar limb salvage rates when compared to angioplasty.

Conclusions: This is the first known study to compare open surgical versus endovascular angiosome-targeted and nonangiosome-targeted revascularization of patients with critical limb ischemia and tissue loss. Enhanced wound healing was observed in open surgical revascularization, independent of angiosome orientation compared to nonangiosome-targeted angioplasty. Interestingly, the open approach is more effective, even compared to angiosome-targeted angioplasty, perhaps because the blood flow pressure is more effective compared to angioplasty. Limb salvage was significantly improved in angiosome-targeted bypass, nonangiosome-targeted angioplasty being associated with the highest risk of major amputation. Some patients are not good candidates for open surgical repair given comorbidities and operative risks. In addition, desired anatomy of revascularization may not always be possible. Endovascular first strategy is effective, especially if there is the ability to achieve angiosome-targeted revascularization. If failure of endovascular approach is expected, such as in patients with long arterial occlusions, bypass surgery despite angiosomal orientation is the best option, especially if tissue loss involves multiple angiosomes and in the setting of an elevated C-reactive protein. Angiosomal revascularization options are important facets to consider with the vascular surgery team in podiatric surgical planning and wound care management.

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