Outcomes of One Straight-Line Flow with and Without Pedal Arch in Patients with Critical Limb Ischemia

SLR - March 2017 - Caleb Davis

Reference: Higashimori A, lida O, Yamauchi Y, Kawasaki D, Nakamura M, Soga Y, Zen K, Yokoi Y. Outcomes of One Straight-Line Flow with and Without Pedal Arch in Patients with Critical Limb Ischemia. Catheter Cardiovasc Interv. 2016 Jan 1;87(1): 129–133.

Reviewed By: Caleb Davis, DPM
Residency Program: St. Francis Hospital and Medical Center, Hartford, CT
 

Podiatric Relevance: Limb salvage is a major part of the podiatric physician's practice. One of the major requirements for limb salvage is adequate perfusion to an area of gangrene or ulceration. The establishment of one uninterrupted infrapopliteal vessel has been established as a prerequisite for wound healing; however, some patients with single vessel runoff will still require limb amputation. Recent literature has stressed the importance of visualizing a patent pedal arch in addition to single vessel runoff in regards to wound healing.

Methods: A level III retrospective cohort study of 312 consecutive patients with critical limb ischemia (CLI) who underwent endovascular therapy. Below-the-knee angiography identified one vessel run off in 137 patients (44 percent). The authors aimed to compare the outcomes between those patients where revascularization resulted in one vessel straight-line flow into a patent pedal arch (76 limbs, Group A) versus those who attained one straight-line flow to the distal end of a tibial vessel without flow into a patent pedal arch (61 limbs, Group B). The study endpoints were amputation-free survival rate, limb salvage rate and wound healing rate at 12 months after EVT.

Results: Comparisons between groups A and B revealed no significant differences in patient characteristics, atherosclerotic risk factors or medication use. In group A, 23 patients had direct revascularization (23/76). In group B, 20 patients had direct revascularization to the site of gangrene/ulcer (20/61). There were no differences between two groups (P=0.75) in regards to direct revascularization. Amputation-free survival differed significantly between groups A and B (88.2 percent vs. 65.6 percent, respectively, P<0.01) at one year. Estimated percentage limb salvage rate differed significantly between groups A and B (98.4 percent vs. 89.3 percent, respectively, P=0.03) at one year. Wound healing rate in groups A and B were 89.4 percent and 80.6 percent P=0.11. Between the two groups, there was no observed difference in amputation-free survival in regards to which vessel was patent; posterior tibial, anterior tibial or peroneal.

Conclusions: There were statistically significant differences in this study that show limb salvage is more frequently achieved in CLI patients with one vessel runoff when there is flow into a patent pedal arch. A limitation of this study is its retrospective comparison study design. Another weak aspect of this study is a relatively short follow-up of one year. A study design with a higher level of scientific evidence, such as a prospective cohort study with longer a follow-up time, is needed.