Predictors and outcomes of restenosis following tibial artery endovascular interventions for critical limb ischemia

Revascularization Outcomes Stratified by Glycemic Control in Patients with Diabetes Mellitus and Chronic Limb-Threatening Ischemia

BACKGROUND

The prevalence of chronic limb-threatening ischemia (CLTI) has increased alongside rising rates of diabetes mellitus (DM). While diabetic patients with CLTI have worse outcomes compared to patients without diabetes, conflicting data exist on the relationship between the severity of DM and CLTI outcomes. Close inspection of the relationship between DM severity and outcomes in CLTI may benefit surgical decision-making and patient education.

METHODS

We retrospectively reviewed patients who received endovascular intervention or surgical bypass for CLTI at our multidisciplinary Limb Preservation Program from 2013 to 2019 to collect patient characteristics using Society for Vascular Surgery (SVS) reporting standards, arterial lesion characteristics from recorded angiograms, and outcomes, including survival, amputation, wound healing, and revascularization patency. Controlled DM was defined as SVS Grade 1 (controlled, not requiring insulin) and Grade 2 (controlled, requiring insulin), while uncontrolled DM was defined as SVS Grade 3 (uncontrolled), and DM severity was assessed using preoperative hemoglobin A1c (HgbA1c) values. Product-limit Kaplan-Meier was used to estimate survival functions. Univariable Cox proportional hazards analyses guided variable selection for multivariable analyses.

RESULTS

Our Limb Preservation Program treated 177 limbs from 141 patients with DM. Patients with uncontrolled DM were younger (60.44 ± 10.67 vs. 65.93 ± 10.89 years old, P = 0.0009) and had higher HgbA1c values (8.97 ± 1.85% vs. 6.79 ± 1.10%, P < 0.0001). Fewer patients with uncontrolled DM were on dialysis compared to patients with controlled DM (15.6% vs. 30.9%, P = 0.0278). By Kaplan-Meier analysis, DM control did not affect time to mortality, limb salvage, wound healing, or loss of patency. However, multivariable proportional hazards analysis demonstrated increased risk of limb loss in patients with increasing HgbA1C (hazard ratio (HR) = 1.96 [1.42-2.80], P < 0.0001) or dialysis dependence (HR = 15.37 [3.44-68.73], P = 0.0003), increased risk of death in patients with worsening pulmonary status (HR = 1.70 [1.20-2.39], P = 0.0026), and increased risk of delayed wound healing in patients who are male (HR = 0.48 [0.29-0.79], P = 0.0495). No independent association existed between loss of patency with any of the variables we collected.

CONCLUSIONS

Patients with uncontrolled DM, as defined by SVS reporting standards, do not have worse outcomes following revascularization for CLTI compared to patients with controlled DM. However, increasing HgbA1c is associated with a greater risk for early amputation. Before revascularization, specific attention to the level of glycemic control in patients with DM is important, even if DM is "controlled." In addition to aggressive attempts at improved glycemic control, those with elevated HgbA1c should receive careful education regarding their increased risk of amputation despite revascularization. Future work is necessary to incorporate the severity of DM into risk models of revascularization for the CLTI population.

The Impact of Clinical Follow-Up After Revascularization on the Outcomes of Patients with Chronic Limb Threatening Ischemia

BACKGROUND

Guidelines for optimal follow-up for patients undergoing lower extremity revascularization (LER) for peripheral arterial disease recommend multiple visits with imaging during the first year followed by yearly monitoring thereafter. Critical limb-threatening ischemia (CLTI) patients are at a greater risk for mortality and limb amputation than claudicants and thus necessitate closer monitoring. The goal of this article is to study the effects of compliance with follow-up after revascularization for patients with CLTI on major amputation rates and mortality.

METHODS

A single-center retrospective chart review of consecutive patients undergoing LER for CLTI was performed. Patients were stratified based on compliance with follow-up to compliant or noncompliant cohorts. Patient characteristics, reinterventions, and perioperative and long-term outcomes were compared between the 2 groups.

RESULTS

There were 356 patients undergoing LER and 61% (N = 218) were compliant. There was no significant difference in baseline characteristics between the 2 groups. Noncompliant patients were more likely to undergo endovascular interventions compared to compliant patients (92.8% vs. 79.4%, P = 0.03). There was no difference in perioperative outcomes between the 2 groups with overall 30-day mortality of 0.6%. After mean follow-up of 2.7 years, compliant patients had greater ipsilateral reintervention rates (49.1% vs. 34.1%, P = 0.005) and overall reintervention rates (61% vs. 44.2%, P = 0.002) compared to noncompliant patients. There was no significant difference in mortality or ipsilateral major amputations between the 2 groups.

CONCLUSIONS

Patients who were compliant with follow-up after LER for CLTI underwent more reinterventions with no difference in mortality or major limb amputation. Further research regarding the threshold for reintervention and the optimal schedule for follow-up in patients with CLTI is needed.

A Retrospective Case Series on Free Flap Reconstruction for Ischemic Diabetic Foot: The Nutrient Flap Further Explained

BACKGROUND

This retrospective case series compares the outcomes and postoperative oxygen levels in patients who underwent free flap versus primary closure/local flap reconstruction for ischemic diabetic foot wounds to determine the influence of free flap on the surrounding ischemic tissues. The authors hypothesized that the free flap would benefit the surrounding ischemic tissue as a nutrient flap by increasing the tissue oxygen content.

METHODS

The patients were divided into two groups: group 1 underwent free flap reconstruction, and group 2 underwent partial foot amputation with primary closure/local flap. Patient demographics, endovascular intervention, surgical outcome, postreconstruction intervention, and prereconstruction and postreconstruction transcutaneous oximetry were analyzed.

RESULTS

Among 54 patients, 36 were in group 1 and 18 were in group 2. There were no differences in patient demographics between the two groups. All patients had successful angioplasty. Statistical significance was noted in postreconstruction intervention in which group 2 required 2.8 ± 2.9 débridements (versus 1.2 ± 2.5 for group 1) and seven of 18 below-knee amputations (versus three of 36 for group 1) (p < 0.05). Transcutaneous partial pressure of oxygen levels were significantly higher in group 1 at 6 months after reconstruction (61.6 ± 7.5 versus 32.6 ± 5.8 mmHg) (p < 0.01).

CONCLUSION

This study shows that the role of the free flap in ischemic diabetic limb may expand beyond that of providing coverage over the vital structures, and it supports the use of the free flap as a nutrient to increase oxygen content in the ischemic diabetic foot.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Statins and Peripheral Arterial Disease: A Narrative Review

Peripheral arterial disease (PAD) is a highly prevalent atherosclerotic condition. In patients with PAD, the presence of intermittent claudication leads to a deterioration in quality of life. In addition, even in asymptomatic cases, patients with PAD are at high risk of cardiac or cerebrovascular events. Treatment of PAD is based on lifestyle modifications; regular exercise; smoking cessation; and control of cardiovascular risk factors, including hypercholesterolemia. A growing number of studies have shown that statins reduce cardiovascular risk and improve symptoms associated with PAD. Current guidelines recommend the use of statins in all patients with PAD in order to decrease cardiovascular events and mortality. However, the prescribing of statins in patients with PAD is lower than in those with coronary heart disease. This review provides relevant information from the literature that supports the use of statins in patients with PAD and shows their potential benefit in decreasing lower limb complications as well as cardiovascular morbidity and mortality.

The Global Anatomic Staging System Does Not Predict Limb Based Patency of Tibial Endovascular Interventions

OBJECTIVE

Anatomic grading systems have historically been poor predictors of patency after endovascular tibial interventions. The Global Vascular Guidelines proposed a new Global Anatomic Staging System (GLASS) to estimate one-year limb-based patency (LBP). The purpose of this study was to determine the association of GLASS with LBP following endovascular tibial interventions.

METHODS

We included all patients presenting to our multidisciplinary diabetic limb preservation service between 01/2012 and 8/2020 who underwent first-time endovascular tibial revascularization for chronic limb-threatening ischemia. Diagnostic angiograms were reviewed to define the preferred target artery pathway and assign a GLASS stage to each treated limb. One-year LBP was calculated and compared across GLASS stages using Kaplan-Meier curves with log-rank tests and Cox proportional hazards models.

RESULTS

We performed tibial revascularization in 96 limbs (5.2% rest pain, 56.3% ulcer, 37.5% gangrene), including isolated tibial interventions in 61.5% and tibial + femoropopliteal interventions in 38.5%. 15.6% of limbs were GLASS stage 1, 28.1% were GLASS stage 2, and 56.3% were GLASS stage 3. Overall, one-year LBP was 43.2 ± 6.3%, and did not differ significantly across GLASS stages (P = 0.42). The hazard ratio for failed LBP was 1.94 (95% CI 0.70-5.41) for GLASS stage 2 and 1.49 (95% CI 0.56-3.94) for GLASS stage 3 limbs (versus GLASS stage 1). When analyzed excluding the calcium modifier, LBP remained similar across GLASS stages (P = 0.72). Major amputation was uncommon, occurring in 9.3 ± 3.4% of limbs at one year, and did not significantly differ by GLASS stage (P = 0.98).

CONCLUSION

The Global Anatomic Staging System did not predict limb-based patency following tibial endovascular interventions. Given the low major amputation rates in this cohort, anatomic complexity should not preclude endovascular limb salvage efforts below the knee.

Medical therapy for cardiovascular and limb-related risk reduction in critical limb ischemia

Critical limb ischemia (CLI) constitutes the most advanced form of peripheral artery disease (PAD) and is characterized by ischemic rest pain, tissue loss and/or gangrene. Optimized medical care and risk factor modification in addition to revascularization could reduce the incidence of cardiovascular events and major adverse limb events, improving patients' quality of life and promising higher survival rates. Adequate adherence to cardioprotective medications, including antithrombotic therapy (e.g., antiplatelets, anticoagulants), cholesterol-lowering agents (e.g., statins, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors), angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), and smoking cessation should be strongly encouraged for patients with CLI. This review examines these guideline-recommended therapies in terms of cardiovascular and limb-related risk reduction in patients with CLI.

Revascularization of multiple tibial arteries is not associated with improved limb salvage

OBJECTIVE

We sought to determine the benefit of performing multiple tibial artery revascularization compared with single vessel revascularization for patients with chronic limb-threatening ischemia (CLTI).

METHODS

We performed a single-center, retrospective cohort study of all patients with CLTI treated with below-the-knee endovascular intervention from 2012 to 2019. Group 1 included patients who had undergone single tibial artery revascularization. Group 2 included patients who had undergone multiple (two or more) tibial artery revascularization. More proximal disease, if present, was treated, in addition to the tibial disease. The primary endpoint was freedom from amputation. The secondary endpoints included the reintervention rates and all-cause mortality.

RESULTS

A total of 527 limbs in 470 patients with CLTI (nonhealing ulcers, 62%; gangrene, 33%; and ischemic rest pain, 5%) were included in the present study. Of the 527 limbs, 245 (46%) had undergone single vessel revascularization and 282 (54%) had undergone multiple vessel revascularization. The mean follow-up was 19 ± 18 months. No difference was found in freedom from amputation between the two groups (68% vs 63%; P = .109). On multivariable analysis, the factors associated with amputation included dialysis (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.16-2.45), dyslipidemia (OR, 1.37; 95% CI, 0.96-1.94), and gangrene (OR, 2.08; 95% CI, 1.50-2.98). No differences were found in the reintervention rates between the two groups (21.2% vs 16.7%; P = .13). The overall survival rate was 73% in both study groups.

CONCLUSIONS

The results from the present large, single-center study have demonstrated that multiple below-the-knee vessel revascularization is not associated with improved limb salvage compared with single vessel revascularization.

"Modern Endovascular Therapy"

INTRODUCTION

The past 25 years have been witness to a revolution in how vascular care is delivered. The majority of arterial and venous interventions have converted from open surgery to minimally invasive percutaneous endovascular procedures.

METHODS

This surgical innovations symposium article reviews current endovascular therapy in multiple vascular beds with a primary focus on carotid artery occlusive disease, aortic pathologies, and lower extremity arterial occlusive disease. Mesenteric arterial occlusive disease and lower extremity venous endovascular therapies are also briefly discussed. Indications for intervention, treatment examples and outcomes analysis are presented. While not reviewed in this article, endovascular therapy has also become first line in the treatment of coronary artery disease, chronic mesenteric arterial occlusive disease, superficial venous reflux, central vein occlusion, and acute venous thrombus intervention when indicated.

CONCLUSION

Endovascular therapies are used in all vascular beds to treat the full spectrum of vascular pathologies. Aneurysm disease, atherosclerotic arterial occlusive disease, acute arterial and venous thrombosis, ongoing hemorrhage, and venous reflux are among the issues which can be addressed by endovascular means. The minimally invasive nature of endovascular treatments in what is largely a very co-morbid patient cohort is an attractive method of avoiding major procedural related morbidity and mortality.

Endovascular Therapy Provides Similar Results of Bypass Graft Surgery in the Treatment of Infrainguinal Multilevel Arterial Disease in Patients with Chronic Limb-Threatening Ischemia in All GLASS Stages

BACKGROUND

Extensive infrainguinal arterial disease still pose a challenge for technical and clinical success of percutaneous angioplasty. The purpose of this study was to compare the results of concomitant femoropopliteal and infrapopliteal percutaneous angioplasty/stenting (PTA/S) with distal bypass graft surgery (BGS) in patients with chronic limb-threatening ischemia (CLTI).

METHOD

In a single-center retrospective investigation between 2011 and 2017, 668 revascularization procedures for CLTI were reviewed. Concomitant femoropopliteal and infrapopliteal disease was identified in 153 CLTI patients, treated with BGS (48) using autogenous veins as substitute or PTA/S in a single procedure (105). A subgroup of patients with complex, extensive arterial lesions (GLASS stage III) received additional analysis. Primary outcomes were limb salvage and survival.

RESULTS

The mean follow-up time was 21.4 months. Patients treated with PTA/S were significantly older and with predominance of females, diabetes and chronic kidney disease. Smoking was more common in patients treated with BGS. The BGS group showed a 36-month survival rate of 73.4%, whereas the PTA/S group presented a survival of 61.3% in the same interval (P = 0.25). The 36-month cumulative limb salvage rate was 53.3 and 59.7% for BGS and PTA/S, respectively (P = 0.24). For GLASS stage III patients, 36-month limb salvage rates were 54.4% for the PTA/S group and 50.2% for the BGS group (P = 0.29). Multivariate analysis pointed poor runoff status (all endovascular patients) and diabetes (GLASS III endovascular patients) as risk factors for limb loss.

CONCLUSION

PTA/S and BGS presented similar results of limb salvage and survival in the treatment of concomitant femoropopliteal and infrapopliteal arterial disease in patients with CLTI, even for patients with extensive and complex arterial disease.

Arterial Reconstruction for Patients with Chronic Limb Ischemia Improves Ambulatory Function and Health-related Quality of Life

BACKGROUND

Arterial reconstruction (AR) for limb ischemia may improve ambulatory function (AF) and health-related quality of life (HR-QoL). However, the efficacy of AR in terms of HR-QoL varies in studies, probably because of cohort differences in disease severity, hemodynamic outcomes, and observation duration. We assessed HR-QoL for patients with various severities of ischemia in a 3-year observational study.

METHODS

We conducted a single-center 3-year observational study using Short Form 36 in patients with chronic limb ischemia. Between 2001 and 2009, 515 consecutive patients had AR, and 330 who underwent elective AR consented to the study. Of the 330 patients (claudicants 49%, critical limb ischemia [CLI] 51%), 307 underwent bypass and 23 endovascular therapy. Postal questionnaires were sent after AR, and 8 domains, the physical and mental component summary (PCS and MCS) scores, and the patient-reported AF were compared, and negative predictors were identified.

RESULTS

Overall, the MCS was minimally affected, but AF and the PCS were impaired. After AR, these measures were significantly improved, and maximum recovery was attained at 6 months. In subgroup analysis, significant predictors of a negative impact on postoperative PCS included age ≥80, CLI, physical aftereffects of stroke (PAS), and previous major amputation (PMA). Of these, PMA was associated with the lowest PCS score, followed by PAS; for these patients, AR contributed minimally to HR-QoL recovery. PCS scores of claudicants attained a maximum value at 6 months; however, PCS scores of CLI patients were significantly lower than intermittent claudication patients (P < 0.0001), and patients with major tissue loss required 2 years to attain maximum PCS recovery.

CONCLUSIONS

This 3-year observational study verified the efficacy of AR in improving AF and HR-QoL. Age ≥80, CLI, PAS, and PMA were definitive predictors, and for patients with the latter 2, AR contributed minimally to improving HR-QoL.

Statin therapy for reduction of cardiovascular and limb-related events in critical limb ischemia: A systematic review and meta-analysis

High-intensity statins are recommended for patients with peripheral artery disease (PAD). Critical limb ischemia (CLI) is the most advanced presentation of PAD. The benefit of statins in the CLI population is unclear based on the existent studies. Our objective was to perform a systematic review and meta-analysis regarding the efficacy of statin therapy in patients with CLI. PRISMA guidelines were followed. PubMed, EMBASE, and Cochrane CENTRAL databases were reviewed up to April 30, 2019. The primary outcomes included amputation rates and all-cause mortality. Secondary outcomes included primary patency rates, amputation-free survival and major adverse cardiac or cerebrovascular events (MACCE). Risk of bias was assessed with the Robins-I tool for observational studies. A random-effects model meta-analysis was performed. Heterogeneity was assessed with I2. Funnel plots and Egger’s test were used to assess publication bias. Nineteen studies including 26,985 patients with CLI were included in this systematic review. Among patients with known data on statin status, 12,292 (49.6%) were on statins versus 12,513 (50.4%) not on statins. Patients treated with statins were 25% less likely to undergo amputation (HR 0.75; 95% CI: 0.59–0.95; I2 = 79%) and 38% less likely to have a fatal event (HR 0.62; 95% CI: 0.52–0.75; I2 = 41.2%). Statin therapy was also associated with increased overall patency rates and lower incidence of MACCE. There was substantial heterogeneity in the analysis for amputation and amputation-free survival (I2 > 70%). In conclusion, statins are associated with decreased risk for amputation, mortality, and MACCE, as well as increased overall patency rates among patients with CLI. Future studies should assess whether other lipid-lowering medications in addition to high-intensity statins can further improve outcomes among patients with CLI. (PROSPERO registration number: CRD42019134160)

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Long-Term Results of Femorotibial Polytetrafluoroethylene Bypass with a Distal Vein Cuff for Critical Limb Ischemia

Objective: Although autologous veins are the first-choice conduit for femorotibial artery bypass, if there are no appropriate autologous veins, we perform femorotibial artery bypass using polytetrafluoroethylene (PTFE) with a distal vein cuff for patients with critical limb ischemia (CLI). This study examined the long-term outcomes of femorotibial artery bypass using PTFE with a Miller's cuff. Materials and Methods: Using prospectively collected data for 444 distal bypasses, a retrospective analysis was conducted for 32 femorotibial PTFE bypasses with a Miller's cuff (PTFE-Miller's cuff) performed for patients with CLI from April 1994 to December 2016. Results: Primary and secondary patency rates of PTFE-Miller's cuff at 3 years were 35.8% and 51.2%, respectively. Limb salvage rate of PTFE-Miller's cuff at 3 years was 71.0%. Conclusion: Although the patency rate was low and failed to yield satisfactory results, the limb salvage rate remained relatively high. Femorotibial PTFE bypass with a Miller's cuff was a useful technique of limb salvage for patients with CLI in whom an appropriate autologous vein could not be used.

The Society for Vascular Surgery practice guidelines on follow-up after vascular surgery arterial procedures

Although follow-up after open surgical and endovascular procedures is generally regarded as an important part of the care provided by vascular surgeons, there are no detailed or comprehensive guidelines that specify the optimal approaches with regard to testing methods, indications for reintervention, and follow-up intervals. To provide guidance to the vascular surgeon, the Clinical Practice Council of the Society for Vascular Surgery appointed an expert panel and a methodologist to review the current clinical evidence and to develop recommendations for follow-up after vascular surgery procedures. For those procedures for which high-quality evidence was not available, recommendations were based on observational studies, committee consensus, and indirect evidence. Recognizing that there are numerous published reports on the role of duplex ultrasound for surveillance of infrainguinal vein bypass grafts, the Society commissioned a systematic review and meta-analysis on this topic. The panel classified the strength of each recommendation and the corresponding quality of evidence on the basis of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system: recommendations were graded either strong or weak, and the quality of evidence was graded high, moderate, or low. The resulting recommendations represent a wide variety of open surgical and endovascular procedures involving the extracranial carotid artery, thoracic and abdominal aorta, mesenteric and renal arteries, and lower extremity arterial revascularization. The panel also identified many areas in which there was a lack of high-quality evidence to support their recommendations. This suggests that there are opportunities for further clinical research on testing methods, threshold criteria, and the role of surveillance as well as on the modes of failure and indications for reintervention after vascular surgery procedures.

Recurrence of Critical Limb Ischemia After Endovascular Intervention in Patients with Diabetic Foot Ulcers

Objective: To establish the rate of clinical recurrence of critical limb ischemia (CLI) in diabetic patients with ischemic foot ulcers (DFUs) treated by percutaneous transluminal angioplasty (PTA). Approach: The study group was composed of 304 patients with ischemic DFUs treated by PTA. We evaluated the rate of clinical recurrence of CLI requiring a second PTA (repeated PTA [rePTA]), the factors related to CLI relapse, and the outcomes of rePTA patients. The follow-up was 12.5 ± 6.6 months. Results: Seventy-four of 304 patients (24.3%) needed rePTA. The mean time to rePTA was 3.5 ± 0.64 months. rePTA group in comparison with no rePTA group had lower rate of healing (28.5% vs. 71.9% p = 0.0001), higher rate of ulcer recurrence (20% vs. 10.3% p = 0.03), major amputation (24.3% vs. 4.3% p = 0.0005), and death (33.3% vs. 7.9% p = 0.002). Glycated hemoglobin, type A1C (HbA1c; 2.2 [1.9-2.7] p = 0.02) and dialysis (1.5 [1.4-3.6] p = 0.006) were independently associated to clinical recurrence of CLI after PTA. Innovation: To identify the outcomes of patients with clinical recurrence of CLI and the clinical factors involved to reduce the rate of restenosis after endovascular treatment and improve the rate of limb salvage. Conclusions: Clinical recurrence of CLI is associated with a high rate of nonhealing ulcer recurrence, major amputation, and death. Dialysis and impaired glycemic control were independent predictors of CLI relapse after endovascular treatment.

Impact of Tibial Runoff on Outcomes of Endovascular Treatment for Femoropopliteal Atherosclerotic Lesions

Objectives:

The aim of this study is to investigate the impact of tibial runoff on outcomes of femoropopliteal interventions for atherosclerotic lesions.

Methods:

A retrospective review of 243 endovascular procedures for femoropopliteal atherosclerotic lesions on 243 limbs of 197 patients was performed.

Results:

The distribution rates of good tibial runoff (runoff score <7) and poor tibial runoff (runoff score ≥7) were 37.0% and 63.0%, respectively. In the poor tibial runoff group, the patients were older ( P = .019), and the proportion of male was lower ( P = .014). There was a significantly higher proportion of rest pain or tissue loss ( P < .001), and the prevalence of stroke ( P = .031) and renal insufficiency ( P = .005) was significantly higher in the poor runoff group. After femoropopliteal intervention, the amputation-free survival ( P = .03) and freedom from ischemia ( P = .003) were significantly lower in the poor runoff group. The interventions targeting below-the-knee (BTK) lesions performed concomitantly for critical limb ischemia or tissue loss with poor tibial runoff did not show a significant advantage in terms of freedom from ischemia; however, minor trends of longer lasting freedom from ischemia were observed when BTK intervention was combined.

Conclusion:

The patients with poor runoff showed significantly lower amputation-free survival and freedom from ischemia. In poor tibial runoff limbs with critical limb ischemia or tissue loss, BTK intervention did not demonstrate additional significant beneficial outcomes; however, there was a minor trend of longer lasting freedom from ischemia after concomitant BTK intervention.

Outcomes of reintervention for recurrent symptomatic disease after tibial endovascular intervention

OBJECTIVE

Tibial interventions for critical limb ischemia are now commonplace. Restenosis and occlusion remain barriers to durability after intervention. The aim of this study was to examine the patient-centered outcomes of open and endovascular reintervention for symptomatic recurrent disease after a primary isolated tibial endovascular intervention.

METHODS

A database of patients undergoing isolated primary lower extremity tibial endovascular interventions between 2006 and 2016 was retrospectively queried. Patients with recurrent critical ischemia (Rutherford 4 and 5) were identified. Outcomes in this cohort were analyzed, and three groups were defined: endovascular reintervention (ie, a repeated tibial or pedal endovascular intervention), bypass (bypass to a tibial or pedal vessel), and primary amputation (ie, above- or below-knee amputation) on the ipsilateral leg. Patient-oriented outcomes of clinical efficacy (absence of recurrent signs or symptoms of critical ischemia, maintenance of ambulation, and absence of major amputation), amputation-free survival (survival without major amputation), and freedom from major adverse limb events (above-ankle amputation of the index limb or major reintervention, such as new bypass graft or jump or interposition graft revision) were evaluated after the reintervention.

RESULTS

There were 1134 patients (56% male; average age, 59 years) who underwent primary tibial intervention for critical ischemia, and 54% presented with symptomatic restenosis and occlusion. Of the 513 patients with recurrent disease, 58% presented with rest pain and the remainder with ulceration. A repeated tibial endovascular intervention was performed in 64%, open bypass in 19%, and below-knee amputation in 17%. Bypass was employed in patients with a good target vessel, venous conduit, and good pedal runoff. Patient-centered outcomes were better in the bypass group compared with the reintervention group (amputation-free survival, 45% ± 9% vs 27% ± 9% [P < .01]; major adverse limb events, 50% ± 9% vs 31% ± 9% [P < .05]; clinical efficacy, 60% ± 7% vs 30% ± 9% [P < .01], mean ± standard error of the mean at 5 years).

CONCLUSIONS

Tibial interventions for critical ischemia are associated with a high rate of reintervention. In patients with good target vessel, venous conduit, and good pedal runoff, bypass appears more durable than repeated tibial endovascular intervention.

Circulating mircoRNA-21 as a predictor for vascular restenosis after interventional therapy in patients with lower extremity arterial occlusive disease

The present study was designed to investigate the role of circulating miRNA-21 (miR-21) in vascular restenosis of lower extremity arterial occlusive disease (LEAOD) patients after interventional therapy. A total of 412 LEAOD patients were enrolled randomly in the present study. According to computed tomography angiography (CTA) and ankle-brachial index (ABI), patients were assigned into the restenosis group and the non-restenosis group. miR-21 expression was detected with quantitative real-time PCR (qRT-PCR) before and after patients underwent interventional therapy. A follow-up period of 6 months was achieved. A receiver operating characteristic (ROC) curve was drawn and the area under the curve (AUC) was calculated to assess the predictive value of miR-21 in vascular restenosis. Patients were older in the restenosis group than in the non-restenosis group. The percentages of patients with diabetes and hypertension were higher in the restenosis group than in the non-restenosis group, and the Fontaine stage exhibited a significant difference between the two groups. miR-21 expression was higher in the restenosis group than in the non-restenosis group. miR-21 expression level was related to age, diabetes and hypertension in the restenosis group. Using miR-21 to predict vascular restenosis yielded an AUC of 0.938 (95% confidence interval (CI): 0.898–0.977), with Youden index of 0.817, sensitivity of 83.5% and specificity of 98.2%. Logistic regression analysis revealed that diabetes and miR-21 expression were the major risk factors for vascular restenosis of LEAOD. miR-21 can be used as a predictive indicator for vascular restenosis of LEAOD after interventional therapy.

Predictors for Better Blood-Flow Restoration of Long-Segmental Below-the-Knee Chronic Total Occlusions after Endovascular Therapy in Diabetic Patients

OBJECTIVE

To prospectively investigate predictors for good restoration of blood flow of below-the-knee (BTK) chronic total occlusions (CTOs) after endovascular therapy in diabetes mellitus (DM) patients.

MATERIALS AND METHODS

A total of 120 long-segmental (≥ 5 cm) BTK, CTOs in 81 patients who underwent recanalization were included in this study. After angioplasty, blood-flow restoration was assessed using modified thrombolysis in myocardial ischemia grades and classified as good flow (grade 3) and poor flow (grade 1/2). One hundred and six CTOs with successful recanalization were divided into a good flow group (GFG; n = 68) and poor flow group (PFG; n = 38). Multivariate logistic regression analyses were undertaken to determine independent predictors of blood-flow restoration. Receiver operating characteristic curves were constructed to determine the best cutoff value. The prevalence of target-lesion restenosis during follow-up was compared between two groups.

RESULTS

Univariate analyses suggested that CTOs in GFG were characterized by lighter limb ischemia (p = 0.03), shorter course of ischemic symptoms (p < 0.01) and lesion length (p = 0.04), more frequent use of intraluminal angioplasty (p = 0.03), and higher runoff score (p < 0.01) than those in PFG. Multivariate regression analyses suggested that distal runoffs (p = 0.001; odds ratio [OR], 10.32; 95% confidence interval [CI]: 4.082-26.071) and lesion length (p < 0.001; OR, 1.26; 95% CI: 1.091-1.449) were independent predictors for good flow restoration. Kaplan-Meier analyses at 12 months showed a higher prevalence of non-restenosis in GFG (p < 0.01).

CONCLUSION

Distal runoffs and lesion length are independent predictors for good flow restoration for long-segmental BTK, CTOs in DM patients who receive endovascular therapy.

Time to Wound Healing and Major Adverse Limb Events in Patients with Critical Limb Ischemia Treated with Endovascular Revascularization

BACKGROUND

There are few studies that quantify the impact of time to wound healing on outcomes after endovascular revascularization of critical limb ischemia (CLI).

METHODS

In this retrospective study, 179 patients with CLI and tissue loss were assessed for adverse events after endovascular therapy. Associations between time to wound healing and outcomes were determined via Cox proportional hazards analysis. The long-term probability of events was assessed with Kaplan-Meier analysis. The primary end point was major adverse limb events (MALE-major amputation, surgical endarterectomy, or bypass). Secondary end points were major amputation, need for repeat endovascular therapy, and mortality.

RESULTS

After multivariable adjustment for time-dependent wound healing, age, renal function, diabetes, and Rutherford class, independent predictors of MALE included the presence of an unhealed wound (hazard ratio [HR], 5.2; 95% confidence interval (CI), 2.3-11.8; P < 0.0001) and creatinine ≥ 2.0 (HR, 2.4; 95% CI, 1.4-4.3; P = 0.003). On Kaplan-Meier analysis, the probability of MALE was greater in patients with unhealed wounds compared with healed wounds (log-rank P < 0.0001). Patients whose wounds healed within 4 months had a lower probability of MALE than patients who did not heal by 4 months (log-rank, P = 0.04). Unhealed wounds were also independently associated with major amputation (HR, 9.0; 95% CI, 2.6-31.1; P = 0.0004), and patients whose wounds healed by 3 months had less major amputation (log-rank, P = 0.04). Unhealed wounds were independently associated with increased risk of mortality (HR, 42.7; 95% CI, 5.7-319.0; P = 0.002) but not repeat revascularization.

CONCLUSIONS

Unhealed wounds are an independent risk factor for MALE, major amputation, and mortality after endovascular treatment of CLI. Wound healing within 3 months is associated with less risk of major amputation, and within 4 months less risk of MALE. A focus should be on achieving wound healing as fast as possible in this population.

Safety and efficacy of cell-based therapy on critical limb ischemia: A meta-analysis

BACKGROUND AIMS

Critical limb ischemia (CLI) is a major health problem worldwide, affecting approximately 500-1000 people per million per annum. Cell-based therapy has given new hope for the treatment of limb ischemia. This study assessed the safety and efficacy of cellular therapy CLI treatment.

METHODS

We searched the PubMed, Embase and Cochrane databases through October 20, 2015, and selected the controlled trials with cell-based therapy for CLI treatment compared with cell-free treatment. We assessed the results by meta-analysis using a variety of outcome measures, as well as the association of mononuclear cell dosage with treatment effect by dose-response meta-analysis.

RESULTS

Twenty-five trials were included. For the primary evaluation index, cell-based therapy significantly reduced the rate of major amputation (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.32-0.60, P = 0.000) and significantly increased the rate of amputation-free survival (OR 2.80, 95% CI 1.70-4.61, P = 0.000). Trial sequence analysis indicated that optimal sample size (n = 3374) is needed to detect a plausible treatment effect in all-cause mortality. Cell-based therapy significantly improves ankle brachial index, increases the rate of ulcer healing, increases the transcutaneous pressure of oxygen, reduces limb pain and improves movement ability. Subgroup analysis indicated heterogeneity is caused by type of control, design bias and transplant route. In the dose-response analysis, there was no significant correlation between cell dosage and the therapeutic effect.

CONCLUSIONS

Cell-based therapy has a significant therapeutic effect on CLI, but randomized double-blind placebo-controlled trials are needed to improve the credibility of this conclusion. Assessment of all-cause mortality also requires a larger sample size to arrive at a strong conclusion. In dose-response analysis, increasing the dosage of cell injections does not significantly improve the therapeutic effects of cell-based therapy.

Use of Tapered Balloons to Recanalize Occluded Below-the-Knee Arteries in Diabetic Patients with Critical Limb Ischemia

BACKGROUND

The aim of this study was to evaluate the outcome of tapered balloon use in recanalization of long occlusions of below-the-knee (BTK) arteries in diabetic patients with critical limb ischemia (CLI).

METHODS

Forty-nine occluded BTK arteries in 35 diabetic patients with CLI were revascularized in our Diabetic Foot Center between January and September 2014 using tapered balloons. Twelve-month outcomes were evaluated in terms of healing of the lesions, survival, limb salvage, primary patency, primary assisted patency, and secondary patency.

RESULTS

The patients were predominantly male (27/35, 77.1%) with a mean age of 70.9 years (±10.3 standard deviation [SD]). During the follow-up (mean duration 12.4 months ± 4 SD), healing of the lesions was obtained in 27 of the 35 cases (77.1%). Estimated 12-month survival and limb salvage were 85.7% and 91.1%, respectively. Estimated 12-month primary patency, primary assisted patency, and secondary patency were 78.3%, 79%, and 88.9%, respectively. Univariate analysis demonstrated that the presence of chronic renal failure affected survival (P = 0.005), and assignment to Rutherford class 6 affected limb salvage (P = 0.005), primary patency (P < 0.001), and primary assisted patency (P < 0.001). Furthermore, the presence of coronary artery disease affected primary patency (P = 0.001) and primary assisted patency (P = 0.05).

CONCLUSIONS

Tapered balloons are a safe and effective means to recanalize long occlusions of BTK arteries in diabetic patients with CLI. Outcomes are poorer in patients with major tissue loss and with a history of coronary artery disease. Further experience with larger groups is needed to validate these outcomes.

[Distal revascularization in diabetic patients with chronic limb ischemia]

Diabetes mellitus is an independent risk factor for peripheral artery disease. Life expectancy is 41 months for diabetic patients with an ischemic ulcer. The characteristics of diabetic arteriopathy make its treatment more difficult than in non-diabetic patients. Few data are available about the surgical treatment of arteriopathy in diabetic patients (including angioplasty or bypass), especially in case of distal arteriopathy. The choice of the procedure depends on multiple factors such as the disease localization, its extent, distal blood flow and vascular disease-related surgical risk. The principal aim of revascularisation is to restore direct flow to the foot in order to ensure wound healing and limb salvage. With percutaneous endoluminal angioplasty, limb salvage can be achieved in more than 80% of patients at 1-3 years. The percutaneous procedure is less invasive than open surgery, there are fewer complications, and morbidity and mortality rates are reduced; moreover, a second procedure remains possible in the future. With bypass surgery, the rate of limb salvage exceeds 80% at five years. Nevertheless, peri-operative mortality reaches 3% and arterial anatomy, patient-related risks factors or venous graft availability may be limitations. New endovascular techniques especially designed for the distal arteries of the lower limbs enable very distal revascularization with morbidity and mortality rates lower than with surgery.

Clinical Predictors of Long-Term Outcomes in Patients With Critical Limb Ischemia Who have Undergone Endovascular Therapy

Clinical predictors of long-term outcomes in patients with critical limb ischemia (CLI) treated with endovascular therapy (EVT) remain unclear. In this study, clinical predictors of long-term outcomes in EVT-treated patients with CLI were investigated. In this prospective, observational study, we analyzed a total of 253 Taiwanese patients with CLI with 314 limbs who underwent EVT between 2005 and 2012. Cox models were used to estimate hazard ratios of death, limb loss, and sustained clinical success (SCS). Multivariate analysis showed that age, atrial fibrillation (AF), end-stage renal disease (ESRD), and albumin were significant predictors of mortality. Patients with coronary artery disease and low albumin levels had a significant risk of major limb amputation, while AF, ESRD, and albumin were significant, independent predictors of SCS. In addition to previously reported predictors, we showed that AF and malnutrition can be used to predict long-term outcome in EVT-treated patients with CLI.