Early evaluation of the infrainguinal revascularization strategy selection tool of the Global Vascular Guidelines for chronic limb-threatening ischemia patients

Primary Limb-Based Patency for Chronic Limb-Threatening Ischemia Treated with Endovascular Therapy Based on the Global Limb Anatomic Staging System

PURPOSE

To validate the correlation between the Global Limb Anatomic Staging System (GLASS) and primary limb-based patency (LBP) and to identify the risk factors associated with LBP loss.

MATERIALS AND METHODS

A single-center retrospective analysis was performed on patients with chronic limb-threatening ischemia (CLTI) who underwent endovascular therapy (EVT) between January 2018 and May 2022. All lesions were categorized into 3 groups (GLASS Stages I, II, and III). The primary LBP rates were analyzed and compared across the GLASS stages. The risk factors for the loss of primary LBP were identified using Cox regression analysis.

RESULTS

In total, 236 limbs from 231 patients were included, with 52 (22%) limbs stratified as GLASS Stage I, 59 (25%) limbs as GLASS Stage II, and 125 (53%) limbs as GLASS Stage III. The 1-year LBP rates for limbs classified as GLASS Stages I, II, and III were 78.8%, 69.5%, and 41.6%, respectively (P < .001). The long-term LBP rate was 54.2% in GLASS Stage I, 38.6% in GLASS Stage II, and 10.5% in GLASS Stage III (P < .001). Multivariate analysis revealed that GLASS stages (GLASS Stage Ⅰ vs Ⅲ, hazard ratio [HR], 0.36; 95% CI, 0.18-0.72; P = .004; GLASS Stage Ⅱ vs Ⅲ, HR, 0.47; 95% CI, 0.25-0.86; P = .02), diabetes, smoking, and sex were independently associated with LBP.

CONCLUSIONS

GLASS Stage III was associated with lower LBP rates in patients with CLTI who underwent EVT. The GLASS stages may serve as prognostic indicators for patients with CLTI after intervention.

Anatomical and clinical factors associated with infrapopliteal arterial bypass outcomes in patients with chronic limb-threatening ischemia

The aim of this study was to identify anatomical and clinical factors associated with limb-based patency (LBP) loss, major adverse limb events (MALEs), and poor amputation-free survival (AFS) after an infrapopliteal arterial bypass (IAB) surgery according to the Global Limb Anatomic Staging System. A retrospective analysis of patients undergoing IAB surgery between January 2010 and December 2021 at a single institution was performed. Two-year AFS, freedom from LBP loss, and freedom from MALEs were assessed using the Kaplan-Meier method. Anatomical and clinical predictors were assessed using multivariate analysis. The total number of risk factors was used to calculate risk scores for subsequent categorization into low-, moderate-, and high-risk groups. IABs were performed on 103 patients. The rates of two-year freedom from LBP loss, freedom from MALEs, and AFS were 71.3%, 76.1%, and 77.0%, respectively. The multivariate analysis showed that poor run-off beyond the ankle and a bypass vein caliber of < 3 mm were significantly associated with LBP loss and MALEs. Moreover, end-stage renal disease, non-ambulatory status, and a body mass index of < 18.5 were significantly associated with poor AFS. The rates of freedom from LBP loss and MALEs and the AFS rate were significantly lower in the high-risk group than in the other two groups (12-month low-risk rates: 92.2%, 94.8%, and 94.4%, respectively; 12-month moderate-risk rates: 58.6%, 84.6%, and 78.3%, respectively; 12-month high-risk rates: 11.1%, 17.6%, and 56.2%, respectively; p < 0.001, p < 0.001, and p < 0.001, respectively). IAB is associated with poor clinical outcomes in terms of LBP, MALEs, and AFS in high-risk patients. Risk stratification based on these predictors is useful for long-term prognosis.

Investigator attitudes on equipoise and practice patterns in the BEST-CLI trial

OBJECTIVES

There has been significant variability in practice patterns and equipoise regarding treatment approach for chronic limb-threatening ischemia (CLTI). We aimed to assess treatment preferences of Best Endovascular vs Best Surgical Therapy in Patients with CLTI (BEST-CLI) investigators prior to and following the trial.

METHODS

An electronic 60-question survey was sent to 1180 BEST-CLI investigators in 2022, after trial conclusion and before announcement of results. Investigators' preferences were assessed across clinical scenarios for both open (OPEN) and endovascular (ENDO) revascularization strategies. Vascular surgeon (VS) surgical and ENDO preferences were compared with a 2010 survey administered to prospective investigators before trial funding.

RESULTS

For the 2022 survey, the response rate was 20.2% and was comprised of VSs (76.3%), interventional cardiologists (11.4%) and interventional radiologists (11.6%). The majority (72.6%) were in academic practice and 39.1% were in practice for >20 years. During initial CLTI work-up, 65.8%, 42.6%, and 55.9% of respondents always or usually ordered an arterial duplex, computed tomography angiography, and vein mapping, respectively. The most common practice distribution between ENDO and OPEN procedures was 70/30. Postoperatively, a majority reported performing routine duplex surveillance of vein bypass (99%), prosthetic bypass (81.9%), and ENDO interventions (86%). A minority reported always or usually using the wound, ischemia, and foot infection (WIfI) criteria (25.8%), GLASS (8.3%), and a risk calculator (14.8%). More than one-half (52.9%) agreed that the statement "no bridges are burned with an ENDO-first approach" was false. Intervention choice was influenced by availability of the operating room or ENDO suite, personal schedule, and personal skill set in 30.1%, 18.0%, and 45.9% of respondents, respectively. Most respondents reported routinely using paclitaxel-coated balloons (88.1%) and stents (67.5%); however, 73.3% altered practice when safety concerns were raised. Among surgeons, 17.8%, 2.9%, and 10.3% reported performing >10 annual alternative autogenous vein bypasses, composite vein composite vein bypasses, and bypasses to pedal targets, respectively. Among all interventionalists, 8%, 24%, and 8% reported performing >10 annual radial access procedures, pedal or tibial access procedures, and pedal loop revascularizations. The majority (89.1%) of respondents felt that CLTI teams improved care; however, only 23.2% had a defined team. The effectiveness of the teamwork at institutions was characterized as highly effective in 42.5%. When comparing responses by VSs to the 2010 survey, there were no changes in preferred treatment based on Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC) II classification or conduit preference. In 2022, OPEN surgery was preferred more for a popliteal occlusion. For clinical scenarios, there were no differences except a decreased proportion of respondents who felt there was equipoise for major tissue loss for major tissue loss (43.8% vs 31.2%) and increased ENDO choice for minor tissue loss (17.6% vs 30.8%) (P < .05).

CONCLUSIONS

There is a wide range of practice patterns among vascular specialists treating CLTI. The majority of investigators in BEST-CLI had experience in both advanced OPEN and ENDO techniques and represent a real-world sample of technical expertise. Over the course of the decade of the BEST-CLI trial, there was overall similar equipoise among VSs.

Perioperative complications following open or endovascular revascularization for chronic limb-threatening ischemia in the BEST-CLI Trial

OBJECTIVE

Anticipated perioperative morbidity is an important factor for choosing a revascularization method for chronic limb-threatening ischemia (CLTI). Our goal was to assess systemic perioperative complications of patients treated with surgical and endovascular revascularization in the Best Endovascular vs Best Surgical Therapy in Patients with CLTI (BEST-CLI) trial.

METHODS

BEST-CLI was a prospective randomized trial comparing open (OPEN) and endovascular (ENDO) revascularization strategies for patients with CLTI. Two parallel cohorts were studied: Cohort 1 included patients with adequate single-segment great saphenous vein (SSGSV), whereas Cohort 2 included those without SSGSV. Data were queried for major adverse cardiovascular events (MACE-composite myocardial infarction, stroke, death), non-serious (non-SAEs) and serious adverse events (SAEs) (criteria-death/life-threatening/requiring hospitalization or prolongation of hospitalization/significant disability/incapacitation/affecting subject safety in trial) 30 days after the procedure. Per protocol analysis was used (intervention received without crossover), and risk-adjusted analysis was performed.

RESULTS

There were 1367 patients (662 OPEN, 705 ENDO) in Cohort 1 and 379 patients (188 OPEN, 191 ENDO) in Cohort 2. Thirty-day mortality in Cohort 1 was 1.5% (OPEN 1.8%; ENDO 1.3%) and in Cohort 2 was 1.3% (2.7% OPEN; 0% ENDO). MACE in Cohort 1 was 4.7% for OPEN vs 3.13% for ENDO (P = .14), and in Cohort 2, was 4.28% for OPEN and 1.05% for ENDO (P = .15). On risk-adjusted analysis, there was no difference in 30-day MACE for OPEN vs ENDO for Cohort 1 (hazard ratio [HR] 1.5; 95% confidence interval [CI], 0.85-2.64; P = .16) or Cohort 2 (HR, 2.17; 95% CI, 0.48-9.88; P = .31). The incidence of acute renal failure was similar across interventions; in Cohort 1 it was 3.6% for OPEN vs 2.1% for ENDO (HR, 1.6; 95% CI, 0.85-3.12; P = .14), and in Cohort 2, it was 4.2% OPEN vs 1.6% ENDO (HR, 2.86; 95% CI, 0.75-10.8; P = .12). The occurrence of venous thromboembolism was low overall and was similar between groups in Cohort 1 (OPEN 0.9%; ENDO 0.4%) and Cohort 2 (OPEN 0.5%; ENDO 0%). Rates of any non-SAEs in Cohort 1 were 23.4% in OPEN and 17.9% in ENDO (P = .013); in Cohort 2, they were 21.8% for OPEN and 19.9% for ENDO (P = .7). Rates for any SAEs in Cohort 1 were 35.3% for OPEN and 31.6% for ENDO (P = .15); in Cohort 2, they were 25.5% for OPEN and 23.6% for ENDO (P = .72). The most common types of non-SAEs and SAEs were infection, procedural complications, and cardiovascular events.

CONCLUSIONS

In BEST-CLI, patients with CLTI who were deemed suitable candidates for open lower extremity bypass surgery had similar peri-procedural complications following either OPEN or ENDO revascularization: In such patients, concern about risk of peri-procedure complications should not be a deterrent in deciding revascularization strategy. Rather, other factors, including effectiveness in restoring perfusion and patient preference, are more relevant.

Validity of the Global Vascular Guidelines in Predicting Outcomes Based on First-Time Revascularization Strategy

BACKGROUND

The Global Vascular Guidelines (GVG) recommend selecting an endovascular versus open-surgical approach to revascularization for chronic limb-threatening ischemia (CLTI), based on the Global Limb Anatomic Staging System (GLASS) and wound, ischemia, and foot infection (WIfI) classification systems. We assessed the utility of GVG-recommended strategies in predicting clinical outcomes.

METHODS

We conducted a single-center, retrospective review of first-time lower-extremity revascularizations within a comprehensive limb-preservation program from 2010 to 2018. Procedures were stratified by (1) treatment concordance with GVG-recommended strategy (concordant versus nonconcordant groups), (2) GLASS stages I-III, and (3) endovascular versus open strategies. The primary outcome was 5-year freedom from major adverse limb events (FF-MALE), defined as freedom from reintervention or major amputation, and secondary outcomes included 5-year overall survival, freedom from major amputation, freedom from reintervention, and immediate technical failure (ITF) during initial revascularization. Kaplan-Meier (KM) survival analysis and multivariate analysis with Cox proportional hazard models were performed on the primary and secondary outcomes.

RESULTS

Of 281 first-time revascularizations for CLTI, 251 (89.3%) were endovascular and 186 (66.2%) were in the concordant group, with a mean clinical follow-up of 3.02 ± 2.40 years. Within the concordant group alone, 167 (89.8%) of revascularizations were endovascular. The concordant group had a higher rate of chronic kidney disease (60.8% vs. 45.3%, P = 0.02), WIfI foot infection grade (0.81 ± 1.1 vs. 0.56 ± 0.80, P = 0.03), and WIfI stage (3.1 ± 0.79 vs. 2.8 ± 1.2, P < 0.01) compared to the non-concordant group. After both KM and multivariate analyses, there were no significant differences in 5-year FF-MALE or overall survival between concordant and non-concordant groups. There was higher freedom from major amputation in the non-concordant group on KM analysis (83.9% vs. 74.2%, P = 0.025), though this difference was non-significant on multivariate analysis (hazard ratio [HR]: 0.49, 95% confidence interval [CI]: 0.21-1.15, P = 0.10). The open group had lower MALE compared to the endovascular group (HR: 0.39, 95% CI: 0.17-0.91, P = 0.029) attributed to a lower reintervention rate in the open group (HR: 0.31, 95% CI: 0.11-0.87, P = 0.026). GLASS stage was not associated with significant differences in outcomes, but the severity of GLASS stage was associated with ITF (2.1% in stage 1, 6.4% in stage 2, and 11.7% in stage 3, P = 0.01).

CONCLUSIONS

In this study, CLTI treatment outcomes did not differ significantly based on whether treatment was received in concordance with GVG-recommended strategy. There was no difference in overall survival between the endovascular and open groups, though there was a higher reintervention rate in the endovascular group. The GVG guidelines are an important resource to help guide the management of CLTI patients. However, in this study, both concordance with GVG guidelines and GLASS staging were found to be indeterminate in differentiating outcomes between complex CLTI patients treated primarily with an endovascular-first approach. The revascularization approach for a CLTI patient is a nuanced decision that must take into account patient anatomy and clinical status, as well as physician skill and experience and institutional resources.

Angiosome Oriented or Least Diseased Vessel, Which Is the Optimal Target Arterial Path for Endovascular Revascularisation in Patients With Diabetic Foot Ulcers?

OBJECTIVE

The aims were to determine whether, when treating diabetic foot ulcers (1), selecting an angiosome directed (AD) vessel as the target arterial path (TAP) when candidate vessels have comparably severe disease impacts outcomes and (2) whether a more severely affected AD vessel or a less severely affected non-angiosome directed (NAD) vessel should be chosen.

METHODS

This was a retrospective observational study. Patients with diabetic foot ulcers who had undergone endovascular revascularisation in the institution between January 2016 and May 2020 and had been followed up for two years were included. Eligible patients were identified retrospectively and relevant data were collected from the institution's electronic medical records. The severity of the lesions was classified using the Global Limb Anatomic Staging System (GLASS). Outcomes between various subgroups were compared according to the severity of the lesions to determine the optimal TAP choice in each case.

RESULTS

The study cohort comprised 215 patients (216 limbs). The affected limbs were classified as follows: 93 (43.1%) as GLASS 1 - 2 AD; 27 (12.5%) as GLASS 1 - 2 NAD, 62 (28.7%) as GLASS 3 AD, and 34 (15.7%) as GLASS 3 NAD groups. In the GLASS 1 - 2 group, rates of ulcer healing, survival, and amputation free survival were higher and time to healing shorter in the AD than NAD group. In the GLASS 3 group, there were no significant differences between the AD and NAD groups for any studied outcome measures, including ulcer healing and overall survival. Using a more severely diseased AD as the TAP did not achieve significantly better outcomes than using a less severely affected NAD vessel.

CONCLUSION

Selecting the AD vessel may achieve better outcomes when two candidate TAPs belong to GLASS 1 - 2, whereas selecting the least diseased vessel as the TAP regardless of AD or NAD status may be preferable in other situations.

A systematic review and meta-analysis of GLASS staging system in the endovascular treatment of chronic limb-threatening ischemia

OBJECTIVE

The objective of this study was to evaluate the application of the Global Anatomic Staging System (GLASS) in the endovascular treatment of chronic limb-threatening ischemia (CLTI).

METHODS

We performed systematic research between June 2019 and February 2022, including articles investigating the relationship of GLASS classification with the outcomes of endovascular interventions in the treatment of CLTI. Data from the included studies were pooled and meta-analyzed. The primary endpoints were limb-based patency (LBP) at 1-year follow-up and immediate technical failure (ITF). Secondary endpoints included major amputation. We performed subgroup analysis between studies that reported on calcium modifier inclusion during GLASS classification and studies that did not.

RESULTS

Eleven studies, including 1816 patients (1975 limbs) met the inclusion criteria. The pooled ITF rates for GLASS stages I, II, and III are 5.52% (95% confidence interval [CI], 3.74%-8.07%), 7.39% (95% CI, 5.32%-10.18%), and 21.07% (95% CI, 13.48%-31.39%) respectively. The pooled LBP for GLASS stages I, II, and III are 68.43% (95% CI, 53.44%-80.37%), 41.52% (95% CI, 18.91%-68.37%), and 38.64% (95% CI, 19.83%-61.57%). The relative risk (RR) for ITF regarding composite GLASS I and II stages vs GLASS III is 3.96 (95% CI, 1.96-7.98). The RR for LBP of GLASS I and II versus GLASS stage III is 1.51 (95% CI, 0.86-2.64). Pooled major amputation rates for the composite GLASS I, II and GLASS III stages are 7.62% (95% CI, 5.44%-10.58%) and 15.43% (95% CI, 11.72%-20.05%) respectively, whereas the RR between GLASS I, II, and GLASS III stages is 1.84 (95% CI, 1.18-2.87).

CONCLUSIONS

Our study demonstrated that patients with CLTI undergoing endovascular interventions classified as GLASS stage III had almost a four-fold risk increase for ITF and 1.84 times the risk of major amputation compared with stages I and II. Additionally, GLASS classification correctly predicted ITF for all three stages, whereas it failed to predict stage I and II LBP outcomes. Safe conclusions regarding LBP cannot be drawn due to the low quality and small number of the included studies, necessitating further research. Furthermore, we displayed the importance of calcium moderator inclusion in the accurate classification of GLASS.

Open Proximal Endarterectomy with Retrograde Access and Stenting: A Novel Technique for Lower Extremity Revascularization

BACKGROUND

Treatment of chronic limb threatening ischemia (CLTI) poses a significant clinical challenge despite recent medical advancements. Chronic total occlusion (CTO) lesions make endovascular approaches to CLTI particularly challenging. Open proximal exposure with retrograde access and stenting (OPERAS) aims to solve this challenge through retrograde subintimal crossing of a CTO with direct visualization of proximal re-entry into the true lumen. We describe this novel technique and present its efficacy in eight patients.

METHODS

We conducted a retrospective case series at a single tertiary academic center. Data for patients who received OPERAS intervention included demographics, peri-operative details, and follow-up information. Statistical analysis was performed on length of stay, major post-operative complications, further intervention, clinical progression at 1 year, and amputation-free survival at 1 year. Immediate technical failure (ITF) and limb-based patency (LBP) at 1 year were calculated.

RESULTS

Nine limbs underwent OPERAS between January 2019 and March 2020. Inflow was achieved with common femoral artery endarterectomy. All limbs underwent balloon angioplasty and stenting of the SFA, and seven underwent the same procedure in the popliteal artery. ITF was 0% for all nine cases. There were no major post-operative complications, and ankle-brachial index significantly improved pre-and post-operatively (P < .001). Eight limbs (88.9%) sustained amputation-free survival at 1 year, and overall LBP was 67% at 1 year.

CONCLUSION

Our study presents a hybrid revascularization option to address severe, anatomically complex limbs (GLASS III) that lack a single autogenous conduit for open surgical revascularization. OPERAS addresses a main point of technical failure of subintimal techniques by directly visualizing the wire in the true lumen. Our data suggest that OPERAS can be effective to: (1) improve technical success of luminal re-entry following a subintimal approach; (2) address inflow concurrently with severe femoropopliteal disease; and (3) can be utilized when distal tissue loss is involved.