Competing Risk Analysis of the Impact of Pedal Arch Status and Angiosome-Targeted Revascularization in Chronic Limb-Threatening Ischemia.

BACKGROUND: In the context of chronic limb-threatening ischemia, the prognostic impact of angiosome-targeted revascularization and of the status of the pedal arch are debated. METHODS: This series includes 580 patients who underwent endovascular (n = 407) and surgical revascularization (n = 173) of the infrapopliteal arteries for chronic limb-threatening ischemia associated with foot ulcer or gangrene. The risk of major amputation after infrapopliteal revascularization was assessed by a competing risk approach. A subanalysis was made separately for patients who underwent endovascular or open surgical revascularization. RESULTS: At 2 years, survival was 65.1% and leg salvage was 76.1%. Multivariable competing risk analysis showed that C-reactive protein ≥10 mg/dL, diabetes, rheumatoid arthritis, increased number of affected angiosomes, and the incomplete or total absence of pedal arch compared with complete pedal arch (CPA) were independent predictors of major amputation after infrapopliteal revascularization. Multivariable analysis showed increasing risk estimates of major amputation in patients with incomplete (subdistribution hazard ratio [SHR], 2.131; 95% confidence interval [95% CI], 1.282-3.543) and no visualized pedal arch (SHR, 3.022; 95% CI, 1.553-5.883) compared with CPA. Pedal arch was important even if angiosome-targeted revascularization was achieved: Angiosome-directed revascularization in presence of CPA had a lower risk of major amputation (adjusted SHR, 0.463; 95% CI, 0.240-0.894) compared with angiosome-directed revascularization without CPA. In the subanalysis, among patients who underwent endovascular revascularization, CPA (SHR, 0.509; 95% CI, 0.286-0.905) and angiosome-targeted revascularization (SHR, 0.613; 95% CI, 0.394-0.956) were associated with a lower risk of major amputation. CONCLUSIONS: Competing risk analysis showed that a patent pedal arch had significant impact on leg salvage and that the subset of patients undergoing endovascular procedure may most benefit of an angiosome-targeted revascularization.

Quality Control of the Foot Revascularization Using Indocyanine Green Fluorescence Imaging.

OBJECTIVES: Critical limb ischemia (CLI) is a clinical diagnosis, confirmed by objective tests, usually ankle-brachial index (ABI), toe pressure (TP) and TcPO2. Furthermore, the anatomical lesions in patients affected by CLI were visualized by ultrasound, angiography, CTA, or MRA. Indocyanine green fluorescence imaging (ICG-FI) is a diagnostic modality for assessing foot perfusion. We aimed to study the usefulness of ICG-FI in the quality control of revascularization. MATERIALS AND METHODS: One hundred and four CLI limbs in 101 patients were studied with ICG-FI using SPY Elite before and after open or endovascular revascularization. ABI and TP were also measured. After ICG-FI, assessment of circulation was done using time-intensity curve derived from the two regions of interest the one being in the plantar side of the foot and the other in the dorsal side of the foot. Three parameters were derived from the curves: maximum intensity (the absolute value of the maximum intensity); intensity rate (the value from the time-intensity curve describing the increase in maximum intensity/s) and SPY10 (the intensity achieved during the first 10 s after the foot starts to gain intensity). RESULTS: Sixty-two limbs presented category 3 of Rutherford classification, 12 limbs category 4, and 30 limbs category 5. Ninety-five technically successful procedures were achieved, 63 (66.3%) endovascular and 32 (33.7%) surgical revascularizations. In 9 (9.5%) patients, an in-line flow from the aorta to the foot was not achieved due to a failure to recanalize the occlusion (n = 7) or due to distal embolization (n = 2). ABI was not reliable in 58 patients (57.4%) mostly due to pseudohypertension and TPs in 49 (48.5%) patients mostly due to previous minor amputations. ICG-FI was successful in all patients. The mean intensity values before and after the procedure in patients who underwent successful revascularization were 81 ± 47 units and 120 ± 5 units of intensity (p < .001) and intensity rates 4.2 ± 4 and 8.0 ± 6.2 units/s (p = .001), respectively. In the PTA patients in whom the revascularization was unsuccessful, no changes were seen in the hemodynamic parameters. In 6 (8.8%) patients who underwent technically successful revascularization, the SPY values were worse after the revascularization than at the baseline. CONCLUSIONS: ICG-FI with SPY Elite provides reliable information on the increase in perfusion after revascularization, in addition to implicating possible failure if there is no improvement in the ICG-FI variables. Unlike ABI and TP, it can be performed in all patients. It gives valuable information to complement traditional assessment methods.

The Prognostic Significance of Different Definitions for Angiosome-Targeted Lower Limb Revascularization.

BACKGROUND: The definition of angiosome-targeted revascularization is confusing, especially when a tissue lesion affects several angiosomes. Two different definitions of direct revascularization exist in the literature. The study aim was (1) to compare the 2 definitions of direct revascularization in patients with foot lesions involving more than one angiosome and (2) to evaluate which definition better predicts clinical outcome. METHODS: This study cohort comprises 658 patients with Rutherford 5-6 foot lesions who underwent infrapopliteal endovascular or surgical revascularization between January 2010 and July 2013. We compared the 2 angiosome-targeted definitions using multivariate analysis; the impact of each angiosome-targeted definition was adjusted for a propensity score obtained by means of nonparsimonious logistic regression. RESULTS: Direct revascularization according to definition A was performed in 367 cases (55.8%) versus 198 cases (30.1%) with definition B. The propensity-score-adjusted analysis showed that definition A of direct revascularization was associated with significantly better wound healing (P < 0.044, hazard ratio [HR] 1.291) and lower amputation rates (P < 0.047, HR 0.706), whereas definition B was associated only with significantly better wound healing (P < 0.029, HR 1.321). The prognostic ability of direct revascularization according to definition A was confirmed in a Cox proportional hazard analysis. CONCLUSIONS: Definition A of direct revascularization was associated with a significantly higher wound healing and leg salvage rate than indirect revascularization in both series. Therefore, it seems that, if the wound spreads over several angiosomes in the forefoot or heel, any angiosome involved in the wound can be targeted.

The Feasibility of Angiosome-Targeted Endovascular Treatment in Patients with Critical Limb Ischemia and Foot Ulcer.

BACKGROUND: To determine wound location according to the angiosome concept and to investigate the feasibility and success of angiosome-based revascularization in below-the-knee (BTK) arteries. METHODS: This was a retrospective study of 161 patients (67.5 ± 25.5 years, 66.5% diabetics) with critical limb ischemia and a foot ulcer, stage Rutherford 5-6, who underwent percutaneous transluminal angioplasty on BTK arteries in 2012. We evaluated feasibility of angiosome-targeted revascularization and the number of angiosomes affected by a wound in each patient. Patients were divided into 3 groups depending on how many BTK vessels were suitable for revascularization. The feasibility was analyzed in each group and in relation to number of affected angiosomes. RESULTS: The wound(s) interfered with one angiosome in only 39 (24.0%) cases. Direct flow into affected angiosome was successfully achieved in 98 (60.9%) cases. If ulceration was limited in one angiosome, the targeted revascularisation was possible in 27 cases (69.2%), if ulceration was extended over 2 angiosomes it was possible in 65 cases (86.7%), if 3 angiosomes were affected it was possible in 36 cases (85.7%), when 4 angiosomes were affected the rate dropped to 25.0% and ulceration extended over 5 angiosomes had no possibility of revascularization. CONCLUSIONS: In critical limb ischemia, the tissue lesion affects several angiosomes in majority of the cases. In thus far published literature, there is existence of more approaches of angiosome-targeted revascularization when more than one angiosome is clinically involved and therefore consensus needs to be achieved for the accurate definition.