Clinical effect of wound depth in critical limb ischemia with tissue loss after endovascular treatment

Revascularisation of Chronic Limb Threatening Ischaemia in Patients with no Pedal Arteries Leads to Lower Midterm Limb Salvage

OBJECTIVE

Chronic limb threatening ischaemia (CLTI) involving the infragenicular arteries is treated by distal angioplasty or pedal bypass; however, this is not always possible, due to chronically occluded pedal arteries (no patent pedal artery, N-PPA). This pattern represents a hurdle to successful revascularisation, which must be limited to the proximal arteries. The aim of the study was to analyse the outcome of patients with CLTI and N-PPA after a proximal revascularisation.

METHODS

All patients with CLTI submitted to revascularisation in a single centre (2019 - 2020) were analysed. All angiograms were reviewed to identify N-PPA, defined as total obstruction of all pedal arteries. Revascularisation was performed with proximal surgical, endovascular, and hybrid procedures. Early and midterm survival, wound healing, limb salvage, and patency rates were compared between N-PPA and patients with one or more patent pedal artery (PPA).

RESULTS

Two hundred and eighteen procedures were performed. One hundred and forty of 218 (64.2%) patients were male, mean age 73.2 ± 10.6 years. The procedure was surgical in 64/218 (29.4%) cases, endovascular in 138/218 (63.3%), and hybrid in 16/218 (7.3%). N-PPA was present in 60/218 (27.5%) cases. Eleven of 60 (18.3%) cases were treated surgically, 43/60 (71.7%) by endovascular and 6/60 (10%) by hybrid procedures. Technical success was similar in the two groups (N-PPA 85% vs. PPA 82.3%, p = .42). At a mean follow up of 24.5 ± 10.2 months, survival (N-PPA 93.7 ± 3.5% vs. PPA 95.3 ± 2.1%, p = .22) and primary patency (N-PPA 53.1 ± 8.1% vs. PPA 55.2 ± 5%, p = .56) were similar. Limb salvage was significantly lower in N-PPA patients (N-PPA 71.4 ± 6.6% vs. PPA 81.5 ± 3.4%, p = .042); N-PPA was an independent predictor of major amputation (hazard ratio [HR] 2.02, 1.07 - 3.82, p = .038) together with age > 73 years (HR 2.32, 1.17 - 4.57, p = .012) and haemodialysis (2.84, 1.48 - 5.43, p = .002).

CONCLUSION

N-PPA is not uncommon in patients with CLTI. This condition does not hamper technical success, primary patency, and midterm survival; however, midterm limb salvage is significantly lower than in patients with PPA. This should be considered in the decision making process.

Scoring Model to Predict Major Amputation in Patients With Chronic Limb-Threatening Ischemia at Wound, Ischemia, and Foot Infection Clinical Stage 4 After Endovascular Therapy

PURPOSE

We investigated the predictors of major amputation (MA) at 1 year and prepared a scoring model to stratify the clinical outcomes of chronic limb-threatening ischemia (CLTI) patients at wound, ischemia, and foot infection (WIfI) clinical stage 4 after endovascular therapy (EVT).

MATERIALS AND METHODS

This study was a retrospective, observational study performed at a single center. A total of 353 CLTI patients (390 limbs) were treated with EVT between April 2007 and December 2016. Among these, limbs at WIfI clinical stages 1, 2, and 3 were excluded, and 194 limbs at WIfI clinical stage 4 (49.7%) were enrolled. The primary endpoint was major amputation (MA) free rate at 1 year. Predictors of MA at 1 year was evaluated by Cox proportional hazard analysis.

RESULTS

At 1 year, the incidence of MA was 18.0% (35 limbs). Cox proportional hazard analysis revealed that hemodialysis (hazard ratio [HR] 2.63; 95% confidence interval [CI], 1.24-5.58; p=0.012), fI3 (HR 2.54; 95% CI, 1.28-5.06; p=0.008), toe wounds (HR 0.29; 95% CI, 0.094-0.88; p=0.029), and visible blood flow to the wound (HR 0.43; 95% CI, 0.21-0.89; p=0.023) were associated with MA. We assigned 1 point for positive predictors of MA, hemodialysis, and fI3; 1 point was deducted for negative predictors of MA, toe wounds, and visible blood flow to the wound. A score of -2 or -1, was defined as the low-risk group, 0 was defined as the intermediate-risk group, and +1 or +2 were defined as the high-risk group. At 1 year, MA free rate, wound healing rate, and amputation-free survival rate were stratified according to a scoring model. MA free rate was 96.6% in low-risk, 72.4% in intermediate-risk, and 67.3% in high-risk (p<0.001); wound healing rate was 67.8% in low-risk, 27.6% in intermediate-risk, and 4.1% in high-risk (p<0.001); amputation-free survival rate was 65.3% in low-risk, 44.8% in intermediate-risk, and 18.4% in high-risk (p<0.001).

CONCLUSIONS

The scoring model based on the predictors of MA stratified clinical outcomes in CLTI patients at WIfI clinical stage 4.

Editor's Choice - Impact of Endovascular Pedal Artery Revascularisation on Wound Healing in Patients With Critical Limb Ischaemia

OBJECTIVE

The present study investigated the impact of endovascular pedal artery revascularisation (PAR) on the clinical outcomes of patients with critical limb ischaemia (CLI).

METHODS

This retrospective analysis of a single centre cohort included 239 patients who underwent endovascular revascularisation of infrapopliteal arteries for a chronic ischaemic wound. PAR was attempted in 141 patients during the procedure. After propensity score matching, there were 87 pairs of patients with and without PAR.

RESULTS

After the matching, the two groups showed balanced baseline clinical and lesion characteristics. PAR was achieved in 60.9% of the PAR group. Direct angiosome flow was more frequently obtained in the PAR group than in the non-PAR group (81.6% vs. 34.5%; p < .001). Subintimal angioplasty (47.1% vs. 29.9%; p = .019) and pedal-plantar loop technique (18.4% vs. 0%; p < .001) were more frequent in the PAR group. At the one year follow up, the PAR group showed greater freedom from major amputation (96.3% vs. 84.2%; p = .009). The wound healing rate, overall survival, major adverse limb event, and freedom from re-intervention did not differ significantly between the two groups. However, the patient subgroup with successful PAR showed a higher wound healing rate than the non-PAR group (76.0% vs. 67.0%; p = .031). In a multivariable Cox proportional hazards regression model, successful PAR (hazard ratio [HR] 1.564, 95% confidence interval [CI] 1.068-2.290; p = .022) was identified as an independent factor associated with improved wound healing, whereas gangrene (HR 0.659, 95% confidence interval [CI] 0.471-0.923; p = .015), C reactive protein >3 mg/dL (HR 0.591, 95% CI 0.386-0.904; p = .015), and pre-procedural absence of pedal arch (HR 0.628, 95% CI 0.431-0.916; p = .016) were associated with impaired wound healing.

CONCLUSION

Successful PAR significantly improved wound healing in patients with CLI. Thus, efforts should be made to revascularise the pedal arteries, especially when the pedal arch is completely absent.

Predictors of Wound Healing Following Revascularization for Chronic Limb-Threatening Ischemia

OBJECTIVES

After surgical or endovascular revascularization, some ischemic lesions will not heal, while some others will heal at a variable period of time from the intervention, indicating a multifactorial interaction between local and systematic "wound healing-promoting" factors. Our objective was to identify predictors of wound healing following revascularization for chronic limb-threatening ischemia (CLTI).

METHODS

A literature review was performed to identify published research concerning clinical, biochemical, and noninvasive methods as predictors of wound healing time and wound-free period after surgical and endovascular revascularization for CLTI.

RESULTS

Our review indicated that potential predictors included local wound factors, wound depth, patient's comorbidities, medications, smoking and alcohol abuse, poor vessel runoff, and direct versus indirect revascularization. Among the clinical biomarkers, platelet-derived growth factor, transforming growth factor β, basic fibroblast growth factor, tumor necrosis factor α, interleukin (IL) 1, and IL-6 have been proposed as potential predictors. Furthermore, the potential of noninvasive microcirculation assessment to predict proper wound healing has been the topic of extensive investigation. Among the novel methods, transcutaneous measurement of oxygen partial pressure, skin perfusion pressure, oxygen-to-see method, indocyanine green fluorescence imaging, and multispectral optoacoustic tomography have shown promising results.

CONCLUSIONS

The risk factor profile of an ischemic lesion in the lower extremities with a delayed/failed healing response, following a successful revascularization, is not fully clarified. Although many predictors have been assessed so far, further research needs to be done to identify the optimal clinical and biochemical indices and the noninvasive technique assessing the microcirculation that is associated with complete wound healing.

Predictors of delayed wound healing after successful isolated below-the-knee endovascular intervention in patients with ischemic foot ulcers

OBJECTIVE

The purpose of this study was to explore the predictors of delayed wound healing and their use in risk stratification for endovascular treatment (EVT) of patients with critical limb ischemia (CLI) due to isolated below-the-knee lesions.

METHODS

Wound healing rates were analyzed retrospectively in patients who underwent successful below-the-knee percutaneous transluminal balloon angioplasty for CLI with tissue loss between May 2008 and June 2013. We also analyzed the independent predictors of delayed wound healing and their use in risk stratification.

RESULTS

The cumulative wound healing rates were 13.9%, 43.8%, 57.7%, and 65.7% at 3, 6, 9, and 12 months, respectively. Multivariate Cox proportional hazards analysis revealed the following as independent predictors of wound nonhealing after initial successful EVT: patients with end-stage renal disease receiving dialysis (hazard ratio [HR], 2.6; 95% confidence interval [CI], 1.0-6.3; P  = .04); albumin level <3.0 g/dL (HR, 2.0; 95% CI, 1.1-3.8; P  = .02); C-reactive protein level >5.0 mg/dL (HR, 3.9; 95% CI, 1.6-9.6; P = .003); major tissue loss (HR, 2.1; 95% CI, 1.3-3.4; P = .003); wound infection (HR, 1.9; 95% CI, 1.2-2.9; P = .005); gangrene (HR, 1.8; 95% CI, 1.2-2.8; P = .008); wound depth (University of Texas grade 3; HR, 3.4; 95% CI, 1.4-8.6; P = .009); duration of ulcer (≥2 months; HR, 2.9; 95% CI, 1.0-8.4; P = .048); insulin use (HR, 1.7; 95% CI, 1.0-2.8; P = .04); and lack of below-the-ankle runoff (HR, 1.9; 95% CI, 1.0-3.4; P = .04).

CONCLUSIONS

The general status of the patient and the target limb's condition are important predictors of wound nonhealing. Regarding the limb's condition, information on wound depth and duration in addition to wound extent and infection would further enable the selection of suitable CLI patients for EVT. Such information would also enable optimal wound management, leading to successful wound healing and improved limb salvage and survival rates.

Clinical Outcomes of Pedal Artery Angioplasty for Patients With Ischemic Wounds: Results From the Multicenter RENDEZVOUS Registry

OBJECTIVES

The aim of this study was to investigate the clinical outcomes of pedal artery angioplasty (PAA) for patients with critical limb ischemia.

BACKGROUND

Pedal artery disease is considered a predictor of delayed wound healing (DH) after endovascular therapy. Adjunctive PAA might improve the speed and extent of wound healing.

METHODS

Consecutive patients with critical limb ischemia (n = 257) presenting with de novo infrapopliteal and pedal artery disease were retrospectively reviewed from a multicenter registry. Patients were divided into 2 groups according to whether PAA was performed (n = 140) or not (n = 117). The rate of wound healing and time to wound healing were compared between these groups. DH score was calculated using the number of independent predictors of DH. Patients were stratified into 3 groups according to DH score: low risk (DH score = 0), moderate risk (DH score = 1 or 2), and high risk (DH score = 3). Estimated efficacy was analyzed for each risk-stratified population.

RESULTS

The rate of wound healing was significantly higher (57.5% vs. 37.3%, p = 0.003) and time to wound healing significantly shorter (211 days vs. 365 days; p = 0.008) in the PAA group. In a multivariate analysis, nonambulatory status, target wound depth (UT grade ≥2), and daily hemodialysis were revealed as predictors of DH. In the moderate-risk population, adjunctive PAA significantly improved the rate of wound healing (59.3% vs. 33.9%; p = 0.001). In the high-risk population, however, PAA did not affect wound healing.

CONCLUSIONS

Patients who underwent PAA showed a higher rate of wound healing and shorter time to wound healing, especially in the moderate-risk population. With regard to wound healing, this aggressive strategy might become a salvage procedure for patients with critical limb ischemia presenting with pedal artery disease.