Primary everolimus-eluting stenting versus balloon angioplasty with bailout bare metal stenting of long infrapopliteal lesions for treatment of critical limb ischemia

Meta-analysis of outcomes from drug-eluting stent implantation in infrapopliteal arteries

BACKGROUND

Percutaneous drug-eluting stent implantation (DESI) is an emerging and promising treatment modality for infrapopliteal artery diseases (IPADs). This systematic review and meta-analysis summarizes and quantitatively analyzes the outcomes of DESI in IPADs considering the hazard ratio (HR), which is a more accurate and appropriate outcome measure than the more commonly used relative risk and odds ratio.

AIM

To explore the superiority of drug-eluting stents (DESs) vs traditional treatment modalities for IPADs.

METHODS

The following postoperative indicators were the outcomes of interest: All-cause death (ACD)-free survival, major amputation (MA)-free survival, target lesion revascularization (TLR)-free survival, adverse event (AE)-free survival, and primary patency (PP) survival. The outcome measures were then compared according to their respective HRs with 95% confidence intervals (CIs). The participants were human IPAD patients who underwent treatments for infrapopliteal lesions. DESI was set as the intervention arm, and traditional percutaneous transluminal angioplasty (PTA) with or without bare metal stent implantation (BMSI) was set as the control arm. A systematic search in the Excerpta Medica Database (Embase), PubMed, Web of Science, and Cochrane Library was performed on November 29, 2022. All controlled studies published in English with sufficient data on outcomes of interest for extraction or conversion were included. When studies did not directly report the HRs but gave a corresponding survival curve, we utilized Engauge Digitizer software and standard formulas to convert the information and derive HRs. Then, meta-analyses were conducted using a random-effects model.

RESULTS

Five randomized controlled trials and three cohort studies involving 2639 participants were included. The ACD-free and MA-free survival HR values for DESI were not statistically significant from those of the control treatment (P > 0.05); however, the HR values for TLR-free, AE-free, and PP-survival differed significantly [2.65 (95%CI: 1.56-4.50), 1.57 (95%CI: 1.23-2.01), and 5.67 (95%CI: 3.56-9.03), respectively].

CONCLUSION

Compared with traditional treatment modalities (i.e., PTA with or without BMSI), DESI for IPADs is superior in avoiding TLR and AEs and maintaining PP but shows no superiority or inferiority in avoiding ACD and MA.

Meta-analysis of outcomes from drug-eluting stent implantation in infrapopliteal arteries

BACKGROUND

Percutaneous drug-eluting stent implantation (DESI) is an emerging and promising treatment modality for infrapopliteal artery diseases (IPADs). This systematic review and meta-analysis summarizes and quantitatively analyzes the outcomes of DESI in IPADs considering the hazard ratio (HR), which is a more accurate and appropriate outcome measure than the more commonly used relative risk and odds ratio.

AIM

To explore the superiority of drug-eluting stents (DESs) vs traditional treatment modalities for IPADs.

METHODS

The following postoperative indicators were the outcomes of interest: All-cause death (ACD)-free survival, major amputation (MA)-free survival, target lesion revascularization (TLR)-free survival, adverse event (AE)-free survival, and primary patency (PP) survival. The outcome measures were then compared according to their respective HRs with 95% confidence intervals (CIs). The participants were human IPAD patients who underwent treatments for infrapopliteal lesions. DESI was set as the intervention arm, and traditional percutaneous transluminal angioplasty (PTA) with or without bare metal stent implantation (BMSI) was set as the control arm. A systematic search in the Excerpta Medica Database (Embase), PubMed, Web of Science, and Cochrane Library was performed on November 29, 2022. All controlled studies published in English with sufficient data on outcomes of interest for extraction or conversion were included. When studies did not directly report the HRs but gave a corresponding survival curve, we utilized Engauge Digitizer software and standard formulas to convert the information and derive HRs. Then, meta-analyses were conducted using a random-effects model.

RESULTS

Five randomized controlled trials and three cohort studies involving 2639 participants were included. The ACD-free and MA-free survival HR values for DESI were not statistically significant from those of the control treatment (P > 0.05); however, the HR values for TLR-free, AE-free, and PP-survival differed significantly [2.65 (95%CI: 1.56-4.50), 1.57 (95%CI: 1.23-2.01), and 5.67 (95%CI: 3.56-9.03), respectively].

CONCLUSION

Compared with traditional treatment modalities (i.e., PTA with or without BMSI), DESI for IPADs is superior in avoiding TLR and AEs and maintaining PP but shows no superiority or inferiority in avoiding ACD and MA.

Stenting versus balloon angioplasty alone in patients with below-the-knee disease: A propensity score-matched analysis

Percutaneous transluminal angioplasty (PTA) is considered an effective treatment in patients with critical limb ischemia (CLI). However, the long-term durability of below-the-knee (BTK) PTA is known to be limited. This study sought to compare the 1-year clinical outcomes following stenting versus balloon angioplasty alone in BTK lesions. This study included 357 consecutive patients (400 limbs, 697 lesions) with BTK lesions who underwent PTA from September 2010 to December 2016. All enrolled patients were treated either by stenting (stent group; 111 limbs of 102 patients) or plain old balloon angioplasty (POBA group; 289 limbs of 255 patients). Stent group includes both primary and provisional stenting. Angiographic outcomes, procedural success, complications, and clinical outcomes were compared between the two groups up to 1 year. After propensity score matching (PSM) analysis, 56 pairs were generated, and the baseline and angiographic characteristics were balanced. The procedural success and complications were similar between the two groups; however, the incidence of procedure-related perforation was higher in the POBA group than in the stenting group [5(11.9%) vs.1 (0.9%), P = 0.009]. Six- to 9-month computed tomography or angiographic follow-up showed similar incidences of binary restenosis, primary patency, and secondary patency. In the 1-year clinical follow-up, there were similar incidences of individual hard endpoints, including mortality, myocardial infarction, limb salvage, and amputation rate, with the exception of target extremity revascularization (TER), which tended to be higher in the stenting group than in the POBA group [21 (20.8%) vs. 11 (10.9%), P = 0.054]. Although there was a trend toward a higher incidence of TER risk in the stenting group, stent implantation, particularly in bail-out stenting seemed to have acceptable 1-year safety and efficacy compared to POBA alone in patients undergoing BTK PTA.

Current evidence of drug-elution therapy for infrapopliteal arterial disease

New and sophisticated endovascular devices, such as drug-eluting stents (DES) and drug-coated balloons (DCB), provide targeted drug delivery to affected vessels. The invention of these devices has made it possible to address the reparative cascade of arterial wall injury following balloon angioplasty that results in restenosis. DESs were first used for the treatment of infrapopliteal lesions almost 20 years ago. More recently, however, DCB technology is being investigated to improve outcomes of endovascular below-the-knee arterial procedures, avoiding the need for a metallic scaffold. Today, level IA evidence supports the use of infrapopliteal DES for short to medium length lesions, although robust evidence that justifies the use of DCBs in this anatomical area is missing. This review summarizes and discusses all available data on infrapopliteal drug-elution devices and highlights the most promising future perspectives.

Revisiting endovascular treatment in below-the-knee disease. Are drug-eluting stents the best option?

Patients with below-the-knee arterial disease are primarily individuals suffering from critical limb ischemia (CLI), while a large percentage of these patients are also suffering from diabetes or chronic renal failure or both. Available data from randomized controlled trials and their meta-analysis demonstrated that the use of infrapopliteal drug-eluting stents (DES), in short- to medium- length lesions, obtains significantly better results compared to plain balloon angioplasty and bare metal stenting with regards to vascular restenosis, target lesion revascularization, wound healing and amputations. Nonetheless, the use of this technology in every-day clinical practice remains limited mainly due to concerns regarding the deployment of a permanent metallic scaffold and the possibility of valid future therapeutic perspectives. However, in the majority of the cases, these concerns are not scientifically justified. Large-scale, multicenter randomized controlled trials, investigating a significantly larger number of patients than those already published, would provide more solid evidence and consolidate the use of infrapopliteal DES in CLI patients. Moreover, there is still little evidence on whether this technology can be as effective for longer below-the-knee lesions, where a considerable number of DES is required. The development and investigation of new, longer balloon-expanding or perhaps self-expanding DES could be the answer to this problem.

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.

Drug-eluting stents versus control therapy in the infrapopliteal disease: A meta-analysis of eight randomized controlled trials and two cohort studies

BACKGROUD

Drug-eluting stents (DES) have been proposed for the treatment of infrapopliteal arteries disease. However, the long-term clinical impact of DES treatment in the vascular territory still remains uncertain.

METHODS AND RESULTS

Pubmed, Embase, Cochrane data, CNKI and Wanfang Data were searched until December 20, 2016 for eligible studies according to identical strategies. Additional data were manually retrieved. STATA ver. 12.0 software were used to Meta-analyze the efficacies of DES and control treatment (BMS or PTA) for infrapopliteal arteries disease. A total of 927 patients from 10 studies (8 randomized controlled trials and 2 cohort studies) were assigned to DESs (n = 484) versus control treatment (n = 443). The results showed that infrapopliteal DES therapy yielded higher primary patency and EFS, while decreased the risk of restenosis at 12-months compared to controls significantly. At 3 years there were no significant differences between two groups, pooled RRs and 95% CI were 1.639 [0.526-5.105], P = 0.394; 1.197 [0.432-3.317], P = 0.729 and 0.992 [0.960-1.024], P = 0.661, respectively. Subgroup analysis showed that infrapopliteal DES therapy using Sirolimus-eluting stents rather than Everolimus-eluting stents provided higher clinic benefits. Infrapopliteal DES therapy yielded no significant difference for TLR, overall survival, Rutherford-Becker class improvement, limb amputation at 12-months and 3-years compared with control treatment.

CONCLUSIONS

The results of the present meta-analysis indicate the non-superiority of infrapopliteal DES therapy over control therapies (BMS/PTA) at 3 years, although short-term benefits at 12 months after DES therapy were evident. Further randomized trials with longer follow-up are required to provide the best scientific evidence regarding the preferred endovascular treatment for patients with occlusive disease of infrapopliteal arteries.

One-Year Outcomes of the Paclitaxel-Eluting, Self-Expanding Stentys Stent System in the Treatment of Infrapopliteal Lesions in Patients With Critical Limb Ischemia

Purpose: To investigate the efficacy of the paclitaxel-coated, self-expanding, nitinol Stentys Stent System in tibioperoneal lesions ≤50 mm long. Methods: The prospective, single-arm, multicenter PES-BTK-70 trial ( ClinicalTrials.gov identifier NCT01630070) evaluated the safety and efficacy of the coronary Stentys Stent System in the treatment of a stenotic or occlusive lesion ≤50 mm long in the tibioperoneal arteries of patients with critical limb ischemia (CLI). Between January 2012 and May 2013, 70 patients (mean age 74.6±9.4 years; 45 men) with CLI [Rutherford category 4 (37, 52.9%) or 5 (33, 47.1%)] received a Stentys drug-eluting stent for the treatment of infrapopliteal stenosis (60, 85.7%) or occlusion (10, 14.3%). The mean lesion length was 17.2 mm (4.0–58.5). The primary outcome measures were primary patency at 6 months (duplex ultrasound) and 12 months (angiography). Secondary outcomes included limb salvage and freedom from target lesion revascularization (TLR). Kaplan-Meier estimates of the outcomes are given with the 95% confidence intervals (CI). Results: Technical and procedure success (<30% residual stenosis without major complications) was achieved in 68 (97.1%) of 70 cases. Primary patency was 87.6% (95% CI 83.5% to 91.7%) at 6 months and 72.6% (95% CI 66.9% to 78.3%) at 1 year. Freedom from TLR was 79.1% at 1 year (95% CI 73.9% to 84.3) and limb salvage was 98.5% (95% CI 97.0 to 100.0). No stent fractures were found by core laboratory review of all follow-up imaging data available up to 12 months. Conclusion: In this study, the self-expanding, nitinol, paclitaxel-eluting, coronary Stentys stent was found to be safe and effective in the below-the-knee region, with results similar to the most recent limus-eluting stent trials.

The Mid-Term Clinical Follow-Up Using Drug-Eluting Balloons on Tibial Artery "De Novo" Lesions in Patients With Critical Limb Ischemia: A Cohort Study

RATIONALE

Restenosis due to intimal hyperplasia (IH) is a major clinical issue that affects the success of lower limb endovascular surgery. After 1 year, restenosis occurs in 40% to 60% of the treated vessels. The possibility to reduce IH using local antiproliferative drugs, such as taxols, has been the rationale for the clinical applications of drug-eluting stents and drug-eluting balloons (DEBs). The purpose of this study was to evaluate the clinical and instrumental efficacy of DEBs versus simple percutaneous transluminal angioplasty (PTA) in patients affected by chronic limb ischemia (CLI) with tibial artery "de novo" lesions.

METHODS

A retrospective analysis was performed and included all consecutive patients who underwent endovascular treatment for CLI in our centers between January 2011 and March 2013. Inclusion criteria were (1) "de novo" tibial artery stenosis and (2) Rutherford class >4. Lesions were further divided by TransAtlantic Inter-Societal Consensus (TASC) classification into groups A, B, C, and D.

RESULTS

Between January 2010 and March 2013, a total of 138 patients underwent simple PTA or DEB for CLI, and the groups were clinically and demographically homogenous. We decided to use DEBs in 70 cases. An improvement in the Rutherford Scale in cumulative and single TASC lesions classification was better in the DEB group (74% vs 51%; P = .024) at 24 months than in the PTA group. In the DEB group, the increase in ankle-brachial index was significantly higher than in the PTA group (P = .039).

CONCLUSIONS

Our experience in addition to the existing literature supports the use of DEB in patients with CLI Rutherford class >3.

Lower limb ischaemia in patients with diabetic foot ulcers and gangrene: recognition, anatomic patterns and revascularization strategies

The confluence of several chronic conditions--in particular ageing, peripheral artery disease, diabetes, and chronic kidney disease--has created a global wave of lower limbs at risk for major amputation. While frequently asymptomatic or not lifestyle limiting, at least 1% of the population has peripheral artery disease of sufficient severity to be limb threatening. To avoid the critical error of failing to diagnose ischaemia, all patients with diabetic foot ulcers and gangrene should routinely undergo physiologic evaluation of foot perfusion. Ankle brachial index is useful when measurable, but may be falsely elevated or not obtainable in as many as 30% of patients with diabetic foot ulcers primarily because of medial calcinosis. Toe pressures and skin perfusion pressures are applicable to such patients.

Long-Term Clinical Outcomes of Infrapopliteal Drug-Eluting Stent Placement for Critical Limb Ischemia in Diabetic Patients

PURPOSE

To evaluate long-term clinical outcomes of infrapopliteal drug-eluting stent (DES) placement in insulin-dependent and non-insulin-dependent diabetic patients with critical limb ischemia (CLI).

MATERIALS AND METHODS

A retrospective analysis was performed of all diabetic patients treated with infrapopliteal DES between January 2002 and September 2012. The study's primary outcome measures were patient survival and major amputation-free survival (AFS). Secondary outcome measures included technical success (defined as the creation of a straight line of blood flow to the foot arch with < 30%), identification of independent predictors of primary outcomes, infrapopliteal target limb repeat intervention-free survival, and procedure-related complications.

RESULTS

In total, 214 patients with CLI (168 men [78.5%]; mean age, 70 y ± 9) in 311 limbs, 562 arteries, and 679 lesions were treated. According to Kaplan-Meier analysis, survival rates were 90.8%, 55.5%, and 36.2%, and AFS rates were 94.9%, 90.4%, and 90.4%, respectively, at 1, 5, and 10 years. Target limb repeat intervention-free survival rates were 79.7%, 55.2%, and 49.7%, respectively, at 1, 5, and 10 years. The overall technical success rate was 97.7%. Cox multivariate analysis demonstrated that procedural failure was the only independent predictor of decreased AFS (hazard ratio [HR], 61.3; 95% confidence interval [CI], 13.8-271.9), and statin use was associated with increased survival (HR, 0.55; 95% CI, 0.31-0.98). Coronary disease (HR, 1.9; 95% CI, 1.01-3.54), dialysis (HR, 2.2; 95% CI, 1.21-4.06), and duration of diabetes (HR, 1.5; 95% CI, 1.02-2.34) were identified as independent predictors of decreased survival. Major complications occurred in four of 479 procedures (0.8%).

CONCLUSIONS

Infrapopliteal DES placement for the management of CLI in diabetic patients resulted in a 55.5% 5-year survival rate, with a 90.4% AFS at 5 and 10 years and a 50.3% repeat intervention rate at 10 years. Technical failure was associated with reduced AFS, and statin intake was associated with increased survival.

Primary Self-EXPANDing Nitinol Stenting vs Balloon Angioplasty With Optional Bailout Stenting for the Treatment of Infrapopliteal Artery Disease in Patients With Severe Intermittent Claudication or Critical Limb Ischemia (EXPAND Study)

Purpose: To compare primary placement of a self-expanding nitinol stent to percutaneous transluminal angioplasty (PTA) with bailout stenting in infrapopliteal arteries of patients with severe intermittent claudication or critical limb ischemia (CLI). Methods: In the EXPAND trial ( ClinicalTrials.gov; identifier NCT00906022), 92 patients (mean age 72.9±9.5 years; 62 men) undergoing treatment for infrapopliteal stenosis in 11 European centers were randomized 1:1 to either self-expanding nitinol stenting with the Astron Pulsar/Pulsar-18 nitinol stent or PTA with bailout stenting. The primary endpoint was sustainable clinical improvement after 12 months, defined as a ≥1-category increase for Rutherford category 3 patients or a ≥2-category increase for CLI patients (Rutherford categories 4/5) compared with baseline. Furthermore, target lesion revascularization (TLR), mortality, and amputation were assessed after 12 months. Results: Sustained clinical improvement at 1 year was observed in 74.3% of the patients treated with primary stenting and in 68.6% of the patients treated with PTA and bailout stenting (p>0.05). Kaplan-Meier estimates of freedom from TLR (76.6% and 77.6%), mortality (7.4% vs 2.1%), and amputation [8.9% (major 6.7%) vs 13.2% (major 8.7%)] at 1 year were not significantly different. Conclusion: Primary self-expanding nitinol stenting did not show statistically different clinical outcomes compared to angioplasty with bailout stenting for infrapopliteal lesions.

Current Phase II drugs under investigation for the treatment of limb ischemia

INTRODUCTION

More than 20 million people in Europe suffer from peripheral arterial disease and nearly 3% develop critical limb ischemia (CLI). Without any medical treatment, CLI has poor prognosis, resulting in limb loss and high mortality rate. Until today, no systemic drug is available for the treatment of CLI and the gold standard method of treatment includes risk factor modification and open surgical or endovascular revascularization. Endovascular local drug delivery devices and novel antithrombotic agents, currently under investigation, aim to improve outcomes of revascularization procedures. The pioneering concept of therapeutic angiogenesis induced by gene and stem cell therapy has been proposed, in an attempt to increase ischemic tissue perfusion.

AREAS COVERED

This review summarizes local and systemic pharmacological treatment of CLI using endovascular or pharmaco-biological therapy and focuses on Phase II trials available for these drugs.

EXPERT OPINION

Novel endovascular technologies combining angioplasty and local drug-delivery continuously improve and will come to be standard of practice for the management of limb ischemia, while new antithrombotic agents will further improve outcomes. Therapeutic angiogenesis represents a safe and promising treatment option. The combination of revascularization with microcirculation improvement induced by gene or stem cell therapy could enhance limb salvage.

Contemporary crossing techniques for infrapopliteal chronic total occlusions

The synergism of technical refinement and advanced technology has significantly increased the popularity of infrapopliteal intervention. Since chronic total occlusion (CTO) is a common disorder among patients with symptomatic infrapopliteal artery disease, infrapopliteal CTO intervention is now evolving rapidly in the field of endovascular intervention. Guidewire crossing through the CTO is essential for a successful procedure. We review up-to-date infrapopliteal CTO crossing techniques based on the current literature.

Management of Infrapopliteal Arterial Disease: Critical Limb Ischemia

According to the TransAtlantic Inter-Society Consensus Document on Management of Peripheral Arterial Disease, "there is increasing evidence to support a recommendation for angioplasty in patients with critical limb ischemia and infrapopliteal artery occlusion." Management of infrapopliteal artery disease starts with diagnosis using modern preprocedural noninvasive and invasive imaging. Interventionalists need to learn the role of chronic total occlusion cap analysis and collateral zone recognition in angiosome-directed interventions for management of critical limb ischemia and be familiar with equipment and device selection and a stepwise approach for endovascular interventions. Interventionalists need to know which crossing tools to use to successfully cross-complex chronic total occlusion caps.

Paclitaxel-coated balloon angioplasty versus drug-eluting stenting for the treatment of infrapopliteal long-segment arterial occlusive disease: the IDEAS randomized controlled trial

OBJECTIVES

This study sought to report the results of a prospective randomized controlled trial comparing paclitaxel-coated balloons (PCB) versus drug-eluting stents (DES) in long infrapopliteal lesions.

BACKGROUND

DES have an established role in the treatment of short infrapopliteal lesions, whereas there is increasing evidence for the use of PCB in longer below-the-knee lesions.

METHODS

Inclusion criteria were patients with Rutherford classes 3 to 6 and angiographically documented infrapopliteal disease with a minimum lesion length of 70 mm. The primary endpoint was target lesion restenosis >50% assessed by digital angiography at 6 months. Secondary endpoints included immediate post-procedure stenosis and target lesion revascularization.

RESULTS

Fifty patients were randomized to undergo infrapopliteal PCB angioplasty (25 arteries in 25 limbs; PCB group) or primary DES placement (30 arteries in 27 limbs; DES group). Immediate residual post-procedure stenosis was significantly lower in DES (9.6 ± 2.2% vs. 24.8 ± 3.5% in PCB; p < 0.0001). At 6 months, 5 patients died (2 in PCB vs. 3 in DES; p = 1.00) and 3 suffered a major amputation (1 in PCB vs. 2 in DES; p = 1.00). In total, 44 angiograms were evaluable with quantitative vessel analysis. Binary (>50%) angiographic restenosis rate was significantly lower in DES (7 of 25 [28%] vs. 11 of 19 [57.9%] in PCB; p = 0.0457). There were no significant differences with regard to target lesion revascularization (2 of 26 [7.7%] in DES vs. 3 of 22 [13.6%] in PCB; p = 0.65). Positive vessel wall remodeling was observed in 3 cases in the PCB arm (3 of 19 [(15.8%)] vs. 0 of 19 [0%] in DES; p = 0.07).

CONCLUSIONS

Compared with PCB in long infrapopliteal lesions, DES are related with significantly lower residual immediate post-procedure stenosis and have shown significantly reduced vessel restenosis at 6 months. PCB may produce positive vessel remodeling. (Infrapopliteal Drug-Eluting Angioplasty Versus Stenting [IDEAS-I]; NCT01517997).

Feasibility of endovascular recanalization of occluded infrapopliteal drug-eluting stents

PURPOSE

To investigate the safety and feasibility of percutaneous endovascular recanalization of late total occlusions of infrapopliteal drug-eluting stents (DES).

METHODS

A retrospective study investigated all 408 infrapopliteal stent procedures performed in 367 patients between January 2007 and October 2013 to identify those who underwent percutaneous reintervention for symptomatic infrapopliteal balloon-expandable DES occlusion. The search identified 49 patients with at least one infrapopliteal DES occlusion in 61 (14.9%) of 408 limbs. Seven (14.3%) patients were excluded from the analysis owing to asymptomatic status (n=6) and acute thrombotic occlusion (n=1), leaving 42 patients who underwent endovascular revascularization of occluded stents in 54 limbs. The study's primary outcomes were technical success and complication rates of endovascular recanalization, while secondary outcomes included limb salvage and the identification of factors influencing primary results.

RESULTS

Technical success was 90.7% (49/54 procedures). Technical failure was seen only in cases of stent collapse and overlapping native popliteal artery-infrapopliteal stent occlusion. According to Kaplan-Meier analysis, survival was 89.6%, 81.1%, and 73.5% at 1, 2, and 3 years, respectively, while limb salvage rates were 86.1%, 79.3%, and 72.7% at the same time points. There was 1 (1.8%) case of distal embolization. No factors influencing outcomes could be identified.

CONCLUSION

Percutaneous recanalization of infrapopliteal stent total occlusions is safe and feasible. Technical failure was noted in cases of stent deformation occurring at the pedal artery and in overlapping native popliteal artery-infrapopliteal stent occlusion.

Clopidogrel responsiveness in patients undergoing peripheral angioplasty

PURPOSE

To investigate the incidence and clinical significance of platelet responsiveness in patients receiving clopidogrel after peripheral angioplasty procedures.

MATERIALS AND METHODS

This prospective study included patients receiving antiplatelet therapy with clopidogrel 75 mg after infrainguinal angioplasty or stenting and who presented to our department during routine follow-up. Clopidogrel responsiveness was tested using the VerifyNow P2Y12 Assay. Patients with residual platelet reactivity units (PRU) ≥ 235 were considered as nonresponders (NR group NR), whereas patients with PRU < 235 were considered as normal (responders [group R]). Primary end points were incidence of resistance to clopidogrel and target limb reintervention (TLR)-free survival, whereas secondary end points included limb salvage rates and the identification of any independent predictors influencing clinical outcomes.

RESULTS

In total, 113 consecutive patients (mean age 69 ± 8 years) with 139 limbs were enrolled. After clopidogrel responsiveness analysis, 61 patients (53.9 %) with 73 limbs (52.5 %) were assigned to group R and 52 patients (46.1 %) with 66 limbs (47.5 %) to group NR. Mean follow-up interval was 27.7 ± 22.9 months (range 3-95). Diabetes mellitus, critical limb ischemia, and renal disease were associated with clopidogrel resistance (Fisher's exact test; p < 0.05). According to Kaplan-Meier analysis, TLR-free survival was significantly superior in group R compared with group NR (20.7 vs. 1.9 %, respectively, at 7-year follow-up; p = 0.001), whereas resistance to clopidogrel was identified as the only independent predictor of decreased TLR-free survival (hazard rate 0.536, 95 % confidence interval 0.31-0.90; p = 0.01). Cumulative TLR rate was significantly increased in group NR compared with group R (71.2 % [52 of 73] vs. 31.8 % [21 of 66], respectively; p < 0.001). Limb salvage was similar in both groups.

CONCLUSION

Clopidogrel resistance was related with significantly more repeat interventions after peripheral angioplasty procedures.

Infrapopliteal lesion morphology in patients with critical limb ischemia: implications for the development of anti-restenosis technologies

PURPOSE

To angiographically evaluate infrapopliteal arterial lesion morphology in a consecutive series of patients presenting with critical limb ischemia (CLI) and undergoing infrapopliteal angioplasty.

METHODS

A prospective analysis was undertaken of a consecutive series of CLI patients undergoing endovascular therapy in a tertiary referral center in the year 2011. Morphological assessment of baseline angiograms obtained prior to revascularization included lesion length, assessment of calcification using a semi-quantitative scoring system, and reference vessel diameter (RVD) measurement. Delta RVDs were assessed subtracting distal RVDs from proximal RVDs. A total of 197 infrapopliteal lesions in 105 CLI patients (n=106 limbs) were assessed. Of these, 136 lesions were treated by endovascular means.

RESULTS

The average length of treated lesions was 87.1±43.8 mm in stenoses and 124.0±78.3 mm in chronic occlusions (p<0.001). Mean RVD proximal to the lesions was 1.88 mm whereas it was 1.66 mm distal to the lesions (p≤0.03). Mean arterial calcification was 1.15.

CONCLUSION

This prospective angiographic series underlines the complex nature and extensive longitudinal involvement of infrapopliteal lesions in CLI patients. These findings should be taken into consideration for anti-restenosis concepts in this challenging subgroup of peripheral artery disease patients.

Below-the-ankle angioplasty and stenting for limb salvage: anatomical considerations and long-term outcomes

PURPOSE

To report the long-term angiographic and clinical results in a series of below-the-ankle (BTA) angioplasty procedures and to present some biomechanical issues related to the unique anatomical geometry of the ankle.

METHODS

We performed a retrospective analysis of BTA angioplasty procedures. Clinical end points included technical success, patient mortality, salvage of the treated foot, and repeat target lesion revascularization. Imaging end points included primary patency, binary restenosis of the target lesion at the 50% threshold, and stent integrity (stent fracture, deformation, or collapse). Univariate subgroup analysis was performed.

RESULTS

In total, 40 limbs in 37 patients (age 73.5 ± 8.2 years) with critical limb ischemia were included and 42 inframalleolar lesions (4.2 ± 1.4 cm) were analyzed. Technical success was achieved in 95.2% (40 of 42). Provisional stent placement was performed in 45.2% (19 of 42). Two patients died, and two major amputations occurred up to 3 years. At 1 year, overall primary vessel patency was 50.4 ± 9.1%, lesion binary restenosis rate was 64.1 ± 8.3%, and repeat intervention-free survival was 93.6 ± 4.3% according to life table analysis of all treated lesions. Pairwise subgroup analysis showed that BTA self-expanding stents were associated with significantly higher restenosis and poorer primary patency compared to plain balloon angioplasty or sirolimus-eluting balloon-expandable stents. Significant deformation and/or fracture of balloon-expandable stents placed BTA were identified in five of 11. Dynamic imaging showed that the dorsalis pedis artery is kinked during foot dorsiflexion, whereas the distal posterior tibial artery is kinked during plantar flexion of the foot.

CONCLUSION

BTA angioplasty for critical limb ischemia treatment is safe and feasible with satisfactory long-term results. BTA stent placement must be reserved for bailout indications.

Systematic review of infrapopliteal drug-eluting stents: a meta-analysis of randomized controlled trials

INTRODUCTION

Drug-eluting stents (DES) have been proposed for the treatment of infrapopliteal arterial disease. We performed a systematic review to provide a qualitative analysis and quantitative data synthesis of randomized controlled trials (RCTs) assessing infrapopliteal DES.

MATERIALS AND METHODS

PubMed (Medline), EMBASE (Excerpta Medical Database), AMED (Allied and Complementary medicine Database), Scopus, CENTRAL (Cochrane Central Register of Controlled Trials), online content, and abstract meetings were searched in September 2012 for eligible RCTs according to the preferred reporting items for systematic reviews and meta-analyses selection process. Risk of bias was assessed using the Cochrane Collaboration's tool. Primary endpoint was primary patency defined as absence of ≥50 % vessel restenosis at 1 year. Secondary outcome measures included patient survival, limb amputations, change of Rutherford-Becker class, target lesion revascularization (TLR) events, complete wound healing, and event-free survival at 1 year. Risk ratio (RRs) were calculated using the Mantel-Haenszel fixed effects model, and number-needed-to-treat values are reported.

RESULTS

Three RCTs involving 501 patients with focal infrapopliteal lesions were analyzed (YUKON-BTX, DESTINY, and ACHILLES trials). All three RCTs included relatively short and focal infrapopliteal lesions. At 1 year, there was clear superiority of infrapopliteal DES compared with control treatments in terms of significantly higher primary patency (80.0 vs. 58.5 %; pooled RR = 1.37, 95 % confidence interval [CI] = 1.18-1.58, p < 0.0001; number-needed-to-treat (NNT) value = 4.8), improvement of Rutherford-Becker class (79.0 vs. 69.6 %; pooled RR = 1.13, 95 % CI = 1.002-1.275, p = 0.045; NNT = 11.1), decreased TLR events (9.9 vs. 22.0 %; pooled RR = 0.45, 95 % CI = 0.28-0.73, p = 0.001; NNT = 8.3), improved wound healing (76.8 vs. 59.7 %; pooled RR = 1.29, 95 % CI = 1.02-1.62, p = 0.04; NNT = 5.9), and better overall event-free survival (72.2 vs. 57.3 %; pooled RR = 1.26, 95 % CI = 1.10-1.44, p = 0.0006; NNT = 6.7).

CONCLUSION

DES for focal infrapopliteal lesions significantly inhibit vascular restenosis and thereby improve primary patency, decrease repeat procedures, improve wound healing, and prolong overall event-free survival.

Peripheral applications of drug-coated balloons: past, present and future

Drug-coated balloon (DCB) technologies represent the latest and hottest development in the field of endovascular treatment of peripheral arterial disease. Initial experience with paclitaxel-coated balloon use in the femoral artery has demonstrated lower mid-term restenosis and superior mid-term clinical outcomes in terms of improved wound healing and reduced repeat angioplasty rates compared with standard balloon angioplasty. Many companies are presently developing and/or improving DCB catheters and therefore ongoing, technical improvements of the already existing platforms, new drugs, and innovative carriers are expected. The ongoing basic research studies and various multicenter randomized, controlled trials that are currently in progress will offer valuable scientific insights regarding the long-term effectiveness and other crucial issues, such as efficacy in various vascular beds, optimal balloon dosage, and post angioplasty antiplatelet therapy. Future applications of these devices also could include in-stent restenosis, anastomotic stenosis of surgical bypass, and benign stenoses of the central venous system. The authors envision that DCB angioplasty will evolve to a major paradigm shift in the endovascular treatment of occlusive vascular diseases.

Stent outcomes for infrapopliteal arterial occlusive disease

This study aimed to determine if the different stent types used in the treatment of infrapopliteal arterial occlusive disease provide any significant advantage over one another at 6 and 12-month follow-up. Consecutive patients undergoing stenting of infrapopliteal lesions were enrolled into a non-randomised prospective registry and followed-up for 1 year. Outcome measures included binary restenosis, target lesion revascularisation, major amputation, and change in Rutherford-Becker score and ankle-brachial index (ABI).Thirty-three patients were enrolled including four patients with bilateral disease. There were 20 target vessels in the drug-eluting stent (DES) group, 13 target vessels in the balloon-expandable bare metal stent (BE-BMS) group and 14 target vessels in the self expandableb are metal stent (SE-BMS) group. Most of the patients in the study were octogenarians except in the SE-BMS group where the mean age was 73 ± 9 years. At 12 months, seven patients had died (DES = 6, BE-BMS = 1) from cardiac and cancer-related diseases. In-stent and peri-stent binary restenosis were non-statistically different between all three groups. There was a nonstatistically significant trend towards higher target vessel revascularisation in the BE-BMS group. Survival curves in all stent types demonstrated restenosis to occur within the first 6 months post-procedure. There was no significant difference in the change in Rutherford-Becker score or ABI between the groups. No major limb amputations occurred during the 12-month period. In conclusion,we did not detect a significant difference in stent performance between the different stent types used to treat infrapopliteal arterial occlusive disease. The choice of stent did not seem to affect patient survival or major amputation-free survival at 1-year follow-up.

Bifurcation stenting after failed angioplasty of infrapopliteal arteries in critical limb ischemia: techniques and short-term follow-up

OBJECTIVES

To report on the efficacy of drug eluting stents (DES) in below the knee lesions involving arterial bifurcations after failed angioplasty.

BACKGROUND

DES have become a mainstay in the treatment of below the knee lesions. However, little is known about the efficacy of DES in infrapopliteal lesions involving the arterial bifurcations. This is the first report on the endovascular treatment of below-the knee bifurcations.

METHODS

11 patients with critical lower limb ischemia and complex infrapopliteal atherosclerotic disease underwent provisional DES placement in infrapopliteal bifurcation lesions. Clinical and angiographic follow-up data were prospectively collected in all patients.

RESULTS

Technical success was achieved in all cases. After 6 months, the two vessel primary patency (2VPP) rate was 54.5% and the 1VPP rate was 81.8%. Between baseline and the follow-up, mean ankle-brachial index increased from 0.31 ± 0.10 to 0.68 ± 0.16, and mean Rutherford-Becker class decreased from 4.73 ± 0.20 to 3.00 ± 1.41 (P < 0.001 for both comparisons).

CONCLUSIONS

Bifurcation stenting techniques, that are described for the coronary arteries can be also performed in the infrapopliteal arteries. However, early reocclusion was frequent in this case series, when stenting was performed in a bail-out setting. If balloon angioplasty alone leads to no sufficient results in bifurcation lesions, a single stent strategy could also be considered.

Evaluation of below-the-knee drug-eluting stents with frequency-domain optical coherence tomography: neointimal hyperplasia and neoatherosclerosis

PURPOSE

To report the use of intravascular frequency-domain optical coherence tomography (FD-OCT) to detect and characterize in-stent neointimal tissue following infrapopliteal drug-eluting stent (DES) placement in patients suffering from critical limb ischemia.

METHODS

This prospective study included 12 patients (7 men; mean age 72.8±7.2 years) who had previously received 21 infrapopliteal sirolimus- or everolimus-eluting stents. The patients returned for regular angiographic follow-up or presented with clinical relapse of symptoms over a mean follow-up of 13.5±7.3 months (range 6-33), at which time FD-OCT imaging was performed. Study endpoints were technical imaging success, defined as successful FD-OCT acquisition and visualization of the arterial lumen and complete vessel wall, and the detection and characterization of in-stent neointimal hyperplasia according to widely accepted OCT criteria.

RESULTS

OCT imaging was successfully completed in 19 of the 21 stents. Binary in-stent restenosis (ISR>50%) was detected in 10/19 stents. Percent restenosis was higher after longer follow-up (60.6%±19.8% ≥1 year vs. 35.3%±20.6% <1 year, p=0.03) and in symptomatic vs. asymptomatic patients (61.5%±20.4% vs. 37.2%±19.3%, p=0.04). Neoatherosclerosis findings included lipid-laden neointima (16/19), neointimal neovascularization (13/19), neointimal calcifications (6/19), and thrombus (5/19); no cases of thin-cap fibroatheroma were identified. Neointimal calcifications were more frequent after ≥12 months of follow-up compared to <12 months (46.6% vs. 0%, p=0.02).

CONCLUSION

FD-OCT of the infrapopliteal arteries following DES placement is safe and feasible and may demonstrate features of developing neointimal neoatherosclerosis. The latter might play a key role as a mechanism of below-the-knee ISR and warrants further investigation.

Cost-effectiveness analysis of infrapopliteal drug-eluting stents

INTRODUCTION

There are no cost-utility data about below-the-knee placement of drug-eluting stents. The authors determined the cost-effectiveness of infrapopliteal drug-eluting stents for critical limb ischemia (CLI) treatment.

METHODS

The event-free individual survival outcomes defined by the absence of any major events, including death, major amputation, and target limb repeat procedures, were reconstructed on the basis of two published infrapopliteal series. The first included spot Bail-out use of Sirolimus-eluting stents versus bare metal stents after suboptimal balloon angioplasty (Bail-out SES).The second was full-lesion Primary Everolimus-eluting stenting versus plain balloon angioplasty and bail-out bare metal stenting as necessary (primary EES). The number-needed-to-treat (NNT) to avoid one major event and incremental cost-effectiveness ratios (ICERs) were calculated for a 3-year postprocedural period for both strategies.

RESULTS

Overall event-free survival was significantly improved in both strategies (hazard ratio (HR) [confidence interval (CI)]: 0.68 [0.41-1.12] in Bail-out SES and HR [CI]: 0.53 [0.29-0.99] in Primary EES). Event-free survival gain per patient was 0.89 (range, 0.11-3.0) years in Bail-out SES with an NNT of 4.6 (CI: 2.5-25.6) and a corresponding ICER of 6,518<euro> (range 1,685-10,112<euro>). Survival gain was 0.91 (range 0.25-3.0) years in Primary EES with an NNT of 2.7 (CI: 1.7-5.8) and an ICER of 11,581<euro> (range, 4,945-21,428<euro>) per event-free life-year gained. Two-way sensitivity analysis showed that stented lesion length >10 cm and/or DES list price >1000<euro> were associated with the least economically favorable scenario in both strategies.

CONCLUSIONS

Both strategies of bail-out SES and primary EES placement in the infrapopliteal arteries for CLI treatment exhibit single-digit NNT and relatively low corresponding ICERs.

Long-term outcomes following primary drug-eluting stenting of infrapopliteal bifurcations

PURPOSE

To investigate the outcomes following primary deployment of drug-eluting stents (DES) for the treatment of infrapopliteal bifurcation lesions in patients suffering from critical limb ischemia (CLI).

METHODS

This was a retrospective study of a registry enrolling all patients suffering from chronic infrapopliteal artery disease and undergoing treatment of tibial bifurcation lesions with DES using 3 techniques: balloon and stent (single stent), T-shape double-stent, and culotte double-stent. The analysis included 39 CLI patients (32 men; mean age 69 ± 10 years) who underwent primary stenting of 41 infrapopliteal bifurcations. Most patients (29, 70.7%) were classified as Rutherford category 4. The mean lesion length was 31.3 ± 13.1 mm. The primary endpoints were amputation-free survival, target lesion revascularization (TLR)-free survival, angiographic 2-vessel primary patency (2VPP), and 1-vessel primary patency (1VPP). Secondary endpoints included survival and angiographic binary restenosis. A Cox regression analysis was performed to identify independent predictors influencing outcomes

RESULTS

Technical success was achieved in all cases. The mean clinical and angiographic follow-up intervals were 47.5 ± 14.8 and 17.5 ± 12.5 months, respectively. According to the Kaplan-Meier analysis, overall survival, amputation-free survival, and TLR-free survival estimates were 79.5%, 84.3%, and 58.0%, respectively, at 5 years. At 12, 24, and 36 months, the 2VPP rates were 77.2%, 47.5%, and 33.9%, and the 1VPP rates were 84.0%, 65.5%, and 54.5%, respectively. Binary restenosis rates were 26.4%, 57.3%, and 82.2% at 12, 24, and 36 months; restenotic lesions were mainly detected at the origin of the bifurcations. The regression model did not identify any independent predictors influencing outcome.

CONCLUSION

DES application for below-the-knee bifurcation lesions was safe and resulted in satisfactory long-term angiographic and clinical outcomes comparable to those reported following infrapopliteal endovascular treatment.

Endovascular treatment of critical ischemia in the diabetic foot: new thresholds, new anatomies

This review discusses the role of endovascular treatment in diabetic patients with critical limb ischemia (CLI). Angioplasty of the femoropopliteal region achieves similar technical success and limb salvage rates in diabetic and nondiabetic patients. Angioplasty in as many as possible tibial vessels is accompanied by more complete and faster ulcer healing as well as better limb salvage rates compared to isolated tibial angioplasty. Targeted revascularization of a specific vessel responsible for the perfusion of a specific ulcerated area is a promising new approach: it replaces revascularization of the angiographically easiest-to-access tibial vessel, even if this is not directly responsible for the perfusion of the ulcerated area, by revascularization of area-specific vascular territories. In conclusion, the endovascular approach shows very high efficacy in ulcer healing for diabetic patients with CLI. Larger prospective studies are now needed to estimate the long-term results of this approach.

Sirolimus-eluting stents for treatment of infrapopliteal arteries reduce clinical event rate compared to bare-metal stents: long-term results from a randomized trial

OBJECTIVES

The study investigated the long-term clinical impact of sirolimus-eluting stents (SES) in comparison with bare-metal stents (BMS) in treatment of focal infrapopliteal lesions.

BACKGROUND

There is evidence that SES reduce the risk of restenosis after percutaneous infrapopliteal artery revascularization. No data from randomized trials are available concerning the clinical impact of this finding during long-term follow-up.

METHODS

The study extended the follow-up period of a prospective, randomized, multicenter, double-blind trial comparing polymer-free SES with placebo-coated BMS in the treatment of focal infrapopliteal de novo lesions. The main study endpoint was the event-free survival rate defined as freedom from target limb amputation, target vessel revascularization, myocardial infarction, and death. Secondary endpoints include amputation rates, target vessel revascularization, and changes in Rutherford-Becker class.

RESULTS

The trial included 161 patients. The mean target lesion length was 31 ± 9 mm. Thirty-five (23.3%) patients died during a mean follow-up period of 1,016 ± 132 days. The event-free survival rate was 65.8% in the SES group and 44.6% in the BMS group (log-rank p = 0.02). Amputation rates were 2.6% and 12.2% (p = 0.03), and target vessel revascularization rates were 9.2% and 20% (p = 0.06), respectively. The median (interquartile range) improvement in Rutherford-Becker class was -2 (-3 to -1) in the SES group and -1 (-2 to 0) in the BMS group, respectively (p = 0.006).

CONCLUSIONS

Long-term event-free survival, amputation rates, and changes in Rutherford-Becker class after treatment of focal infrapopliteal lesions are significantly improved with SES in comparison with BMS. (YUKON-Drug-Eluting Stent Below the Knee-Randomised Double-Blind Study [YUKON-BTX]; NCT00664963).