Below-the-Knee Endovascular Revascularization: A Position Statement

Patients with chronic limb-threatening ischemia, the terminal stage of peripheral artery disease, are frequently afflicted by below-the-knee disease. Although all patients should receive guideline-directed medical therapy, restoration of inline flow is oftentimes necessary to avoid limb loss. Proper patient selection and proficiency in endovascular techniques for below-the-knee revascularization are intended to prevent major amputation and promote wound healing. This review, a consensus among an international panel of experienced operators, provides guidance on these challenges from an endovascular perspective and offers techniques to navigate this complex disease process.

Drug-Eluting Resorbable Scaffold versus Angioplasty for Infrapopliteal Artery Disease

BACKGROUND

Among patients with chronic limb-threatening ischemia (CLTI) and infrapopliteal artery disease, angioplasty has been associated with frequent reintervention and adverse limb outcomes from restenosis. The effect of the use of drug-eluting resorbable scaffolds on these outcomes remains unknown.

METHODS

In this multicenter, randomized, controlled trial, 261 patients with CLTI and infrapopliteal artery disease were randomly assigned in a 2:1 ratio to receive treatment with an everolimus-eluting resorbable scaffold or angioplasty. The primary efficacy end point was freedom from the following events at 1 year: amputation above the ankle of the target limb, occlusion of the target vessel, clinically driven revascularization of the target lesion, and binary restenosis of the target lesion. The primary safety end point was freedom from major adverse limb events at 6 months and from perioperative death.

RESULTS

The primary efficacy end point was observed (i.e., no events occurred) in 135 of 173 patients in the scaffold group and 48 of 88 patients in the angioplasty group (Kaplan-Meier estimate, 74% vs. 44%; absolute difference, 30 percentage points; 95% confidence interval [CI], 15 to 46; one-sided P<0.001 for superiority). The primary safety end point was observed in 165 of 170 patients in the scaffold group and 90 of 90 patients in the angioplasty group (absolute difference, -3 percentage points; 95% CI, -6 to 0; one-sided P<0.001 for noninferiority). Serious adverse events related to the index procedure occurred in 2% of the patients in the scaffold group and 3% of those in the angioplasty group.

CONCLUSIONS

Among patients with CLTI due to infrapopliteal artery disease, the use of an everolimus-eluting resorbable scaffold was superior to angioplasty with respect to the primary efficacy end point. (Funded by Abbott; LIFE-BTK ClinicalTrials.gov number, NCT04227899.).

Efficacy and Safety of Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold in Peripheral Artery Disease: A Single-Arm Meta-Analysis

PURPOSE

This study aimed to evaluate the benefits and risks of patients with peripheral artery disease (PAD) treated with Absorb everolimus-eluting bioresorbable vascular scaffold (BVS) by analyzing all the published studies on the clinical characteristics of patients with PAD.

MATERIALS AND METHODS

PubMed, Embase, and the Cochrane Library were searched for relevant studies. Efficacy, safety, and basic characteristics were analyzed.

RESULTS

Four studies were included in meta-analysis, including a total number of 155 patients with PAD. The pooled overall primary patency, freedom from target lesion revascularization (TLR), symptom resolution, and wound healing were 90%, 96%, 94%, and 86%, respectively. The pooled perioperative complication and all-cause mortality were 4% and 9%, respectively. Preoperative total occlusion was detected in 43 of 192 lesions (22%). The mean lesion length was 27.26 mm. In terms of comorbidities, the pooled percentage of hypertension, hyperlipidemia, diabetes mellitus, coronary artery disease, chronic kidney disease history, and smoking were 65%, 74%, 49%, 43%, 20%, and 57%, respectively.

CONCLUSION

Among these studies, hypertension, hyperlipidemia, and diabetes mellitus were the most common comorbidities in patients with PAD. The Absorb everolimus-eluting BVS was safe and showed the favorable clinical outcomes in both patency and TLR, especially in infrapopliteal disease with heavy calcification. The conclusions of this meta-analysis still needed to be verified by more relevant studies with more careful design, more rigorous execution, and larger sample size.

Outcomes of the paclitaxel-eluting Eluvia stent for long femoropopliteal lesions in Asian patients with predominantly chronic limb-threatening ischemia

The fluoropolymer-coated, paclitaxel-eluting Eluvia stent has shown promising results for the endovascular treatment of femoropopliteal artery lesions in patients with claudication. The aim of the current study was to evaluate efficacy and safety outcomes of the Eluvia stent for the treatment of long femoropopliteal lesions in Asian patients. This is a single-center, retrospective study. The primary endpoint was primary patency at 1 year. Secondary outcomes were 30-days complication rate, technical success, 1-year freedom from clinically driven target lesion revascularization (CD-TLR), limb salvage, survival, amputation-free survival (AFS), wound healing, and clinical improvement. A total of 64 patients with 67 femoropopliteal lesions were included; 78% suffered from diabetes and 84% had chronic limb-threatening ischemia (CLTI). Of those with ischemic wounds, 79% did not have run-off to the foot. Mean lesion length was 193 ± 128 mm and 52% were severely calcified. Primary patency at 1 year was 84% in the overall cohort and 91% in patients with complete lesion coverage with the Eluvia stent. Technical success was achieved in 100% of the cases and 30-day complications occurred in six patients. Twelve-month freedom from CD-TLR, limb salvage, survival, and AFS were 92%, 93%, 85%, and 80%, respectively. In 80% of patients, complete wound healing was experienced and 84% had clinical improvement after 1 year. The Eluvia stent showed promising 12-month patency and clinical results for femoropopliteal treatment in this CLTI-dominant patient population with severely calcified, long lesions. Patient numbers were, however, small; larger trials are required to validate these findings. Aneurysmal change seen in some cases also needs further investigation.

Early and Midterm Experience With the Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold in Asian Patients With Chronic Limb-Threatening Ischemia: One-Year Clinical and Imaging Outcomes From the DISAPEAR Registry

Purpose: To report an experience with the Absorb bioresorbable vascular scaffold (BVS) in an Asian cohort with chronic limb-threatening ischemia (CLTI) from the DISAPEAR ( Drug Impregnated Bioresorbable Stent in Asian Population Extremity Arterial Revascularization) registry. Materials and Methods: A retrospective analysis was conducted of 41 patients (median age 64 years; 23 men) with CLTI owing to >50% de novo infrapopliteal lesions (n=53) treated with the Absorb BVS between August 2012 and June 2017. The majority of patients (37, 90%) had diabetes, 24 (59%) had ischemic heart disease, and 39 (95%) had Rutherford category 5/6 ischemia with tissue loss. The mean lesion length was 22.7±17.2 mm; 10 (24%) lesions were severely calcified. Assessments included technical success, primary patency, freedom from clinically-driven target lesion revascularization (CD-TLR), amputation-free survival, limb salvage, complete wound healing, resolution of rest pain, and resolution of CLTI without TLR at 6 and 12 months after the index intervention. Results: Overall, 69 scaffolds were implanted in the 53 lesions, with 100% technical success. There were no deaths within 30 days of the index procedure. The primary patency rates at 6 and 12 months were 95% and 86%, respectively. The corresponding rates of freedom from CD-TLR were 98% and 93%, respectively. Freedom from major amputation was 98% at both time points, and amputation-free survival was 93% and 85% at 6 and 12 months after the index procedure. Wound healing occurred in 31 patients (79%) with Rutherford category 5/6 ischemia by the end of 12 months. Conclusion: The Absorb BVS demonstrated good 1-year patency and clinical outcomes in CLTI patients with complex infrapopliteal disease.

Bioresorbable Vascular Scaffolds-Dead End or Still a Rough Diamond?

Percutaneous coronary interventions with stent-based restorations of vessel patency have become the gold standard in the treatment of acute coronary states. Bioresorbable vascular scaffolds (BVS) have been designed to combine the efficiency of drug-eluting stents (DES) at the time of implantation and the advantages of a lack of foreign body afterwards. Complete resolution of the scaffold was intended to enable the restoration of vasomotor function and reduce the risk of device thrombosis. While early reports demonstrated superiority of BVS over DES, larger-scale application and longer observation exposed major concerns about their use, including lower radial strength and higher risk of thrombosis resulting in higher rate of major adverse cardiac events. Further focus on procedural details and research on the second generation of BVS with novel properties did not allow to unequivocally challenge position of DES. Nevertheless, BVS still have a chance to present superiority in distinctive indications. This review presents an outlook on the available first and second generation BVS and a summary of results of clinical trials on their use. It discusses explanations for unfavorable outcomes, proposed enhancement techniques and a potential niche for the use of BVS.

Three-Year Results of the Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold in Infrapopliteal Arteries

Purpose: To investigate the midterm performance of the everolimus-eluting Absorb bioresorbable vascular scaffold (BVS) for the treatment of symptomatic infrapopliteal atherosclerotic disease. Methods: A single-center study prospectively enrolled 48 symptomatic patients (mean age 82.1±8.0 years; 27 men) between September 2013 and February 2018 to evaluate the Absorb everolimus-eluting BVS system in distal popliteal and tibial lesions. Mean lesion length was 20.1±10.8 mm. Following predilation, up to 2 BVS were implanted in target lesions in 55 limbs. Clinical and duplex ultrasound follow-up was performed at 1, 3, 6, 12, 24, 36, and 48 months to determine 30-day morbidity and midterm Kaplan-Meier estimates of binary restenosis, clinically-driven target lesion revascularization (CD-TLR), amputation, and mortality. Results: Seventy-one scaffolds were implanted to treat 61 lesions. Technical success was achieved in all patients, with no amputation, death, or target limb bypass surgery within 30 days of the index procedure. There was 1 early thrombotic occlusion of 2 BVS in a previously anticoagulated patient not given antiplatelet medication after the procedure. During a mean follow-up of 24.0±15.3 months, 11 (23%) patients died; the remaining 37 were available for follow-up. Binary restenosis (50%–75%) was detected in 6 (8%) scaffolds. Primary patency estimates at 12, 24, and 36 months were 92.2%, 90.3%, and 81.1%; freedom from CD-TLR estimates were 97.2%, 97.2%, and 87.3% at the same time points. No late scaffold thrombosis has been observed. The majority of the 55 limbs (51, 93%) were clinically improved; 4 (7%) were unchanged. Thirty-six (92%) of 39 limbs treated for tissue loss achieved complete wound healing, with no major amputation (limb salvage 100%). Conclusion: Midterm follow-up demonstrates excellent safety, patency, and freedom from CD-TLR rates using the Absorb bioresorbable vascular scaffold below the knee.