Surgical and Endovascular Therapies for Below-the-Knee Peripheral Arterial Disease: A Contemporary Review

Peripheral arterial disease (PAD) represents one of the most prevalent cardiovascular disease processes and carries a high burden of morbidity and mortality. Patients with chronic limb-threatening ischemia (CLTI), the most severe manifestation of PAD, have the highest rates of cardiovascular morbidity and mortality of the overall PAD population. Patients with below-the-knee (BTK) PAD have an increased propensity toward CLTI due to small-vessel caliber and the frequently comorbid conditions of end-stage renal disease and diabetes mellitus, which tend to affect small artery beds preferentially. For those with BTK PAD with CLTI, the standard of care is revascularization. Early revascularization was performed using surgical bypass. However, endovascular techniques, starting with percutaneous transluminal angioplasty and expanding to the modern armamentarium of adjunctive devices and therapies, have become standard of care for most patients with CLTI due to BTK PAD. In this review, we will discuss the modern surgical and endovascular approaches to revascularization, as well as devices that are currently in development or preapproval study for the treatment of BTK PAD.

Randomized clinical trial to compare the efficacy of self-expanding bare metal nitinol stent and balloon angioplasty alone for below-the-knee lesions following successful balloon angioplasty: 1-year clinical outcomes

This prospective, multicenter, randomized study aimed to compare the 1-year clinical outcomes after primary stenting with self-expanding bare metal nitinol stent (SENS) and plain old balloon angioplasty (POBA) in patients with critical limb ischemia (CLI) and below-the-knee (BTK) lesions. Overall, 119 patients with CLI and BTK lesions were randomized to POBA alone (POBA group, 61 patients) or primary stenting with SENS (stenting group, 58 patients) after achieving acceptable POBA results in target BTK lesions. Clinical outcomes including amputation and revascularization rates were prospectively compared for 1 year. After 1 year, similar incidence rates of individual clinical endpoints, including cardiac death (6.5% vs. 5.1%, p > 0.999), myocardial infarction (1.6% vs. 0.0%, p > 0.999), repeat revascularization (19.6% vs. 18.9%, p = 0.922), target lesion revascularization (13.1% vs. 17.2%, p = 0.530), and amputation (4.9% vs. 0.0%, p = 0.244), were observed. POBA appeared to have acceptable treatment outcomes compared with primary stenting with SENS after 1 year in CLI patients with BTK lesions undergoing percutaneous transluminal angioplasty (PTA).

Peripheral Arterial Disease: A Narrative Review

Peripheral arterial disease (PAD) describes the partial or complete occlusion of blood flow in the distal arteries of the body. A decreased arterial patency may occur due to a reduction in the elasticity or diameter of the vessel. The goal of interventions is to decrease incidence and reduce complications by identifying and minimizing the primary causes. This paper discusses PAD affecting the aortoiliac, common femoral, and femoropopliteal arteries. In a significant portion of the population, PAD may lack usual symptoms such as limb pain, claudication, and diminished pulses. Imaging techniques become crucial to ensuring timely diagnosis, monitoring treatment effectiveness, and preventing recurrence. Duplex ultrasound (DUS) is a cheap and non-invasive preliminary technique to detect atherosclerotic plaques and grade arterial stenosis. Magnetic resonance angiography (MRA) provides the added advantage of minimizing artifacts. Digital subtraction angiography (DSA) remains the gold standard for grading the degree of stenosis but is only employed second-line to DUS or MRA due to the high dose of nephrotoxic contrast. Computed tomography angiography (CTA) is able to overcome the anatomical limitations of DUS and MRA and proves to be a suitable alternative to DSA in patients with renal disease. Preventative measures involve monitoring blood pressure, cholesterol levels, and tobacco usage. First-line treatment options include endovascular procedures as well as surgical interventions in cases of significant arterial involvement. Endovascular treatments involve the use of balloon angioplasty, drug-coated balloons, and drug-coated stents, to name a few, that serve as minimally invasive techniques to manage PAD. Surgical procedures, although more complex, are considered gold-standard treatment options for long and intricate lesions. Endovascular methods are generally preferred over surgical options as the complication risk is severely reduced and the rates of reintervention are comparable to surgical options.

The efficacy and safety of different endovascular modalities for infrapopliteal arteries lesions: A network meta-analysis of randomized controlled trials

Background

Endovascular treatment has become the first-line therapy for infrapopliteal artery occlusive disease (IPOD), while the optimal endovascular method remains to be determined. We performed a network meta-analysis (NWM) of randomized controlled trials (RCTs) to simultaneously compare the outcomes of different endovascular modalities for IPOD.

Methods and results

The Pubmed, Embase, and Cochrane databases were used as data sources. The NWM approach used random-effects models based on the frequentist framework. In total, 22 eligible RCTs (44 study arms; 1,348 patients) involving nine endovascular modalities or combinations [balloon angioplasty (BA), drug-coated balloon (DCB), drug-eluting stent (DES), atherectomy device + BA (AD + BA), AD + DCB, balloon-expandable bare metal stent (BMS), self-expanding stent (SES), absorbable metal stents (AMS), and inorganics-coated stent (ICS)] were included. BA had a lower 12-month primary patency rate than DCB (RR 0.50, CI 0.27, 0.93) and AD + DCB (RR 0.34, CI 0.12, 0.93). AD + DCB decreased 6-month TLR compared with AMS (RR 0.15, CI 0.03, 0.90), and DES decreased it compared with BMS (RR 0.25, CI 0.09, 0.71). DCB had a lower 6-month TLR rate than AMS (RR 0.26, CI 0.08, 0.86) and BA (RR 0.51, CI 0.30, 0.89). BA had a higher 12-month TLR rate than DCB (RR 1.76, CI 1.07, 2.90). According to the value of the surface under the cumulative ranking curve (SUCRA), AD + DCB was considered the best treatment in terms of primary patency at 6 months (SUCRA = 87.5) and 12 months (SURCA = 91). AD + BA was considered the best treatment in terms of 6-month TLR (SUCRA = 83.1), 12-month TLR (SURCA = 75.8), and 12-month all-cause mortality (SUCRA = 92.5). In terms of 12-month major amputation, DES was considered the best treatment (SUCRA = 78.6), while AD + DCB was considered the worst treatment (SUCRA = 28.8). Moreover, AD + BA always ranks higher than AD + DCB in the comparison including these two combinations. Subgroup analyses of modalities without stenting did not significantly change the primary outcomes.

Conclusion

ADs showed noteworthy advantages in multiple terms for IPOD except for 12-month major amputation. AD + BA may be a better method for IPOD than AD + DCB. The efficacy and safety of ADs are worthy of further investigation.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42022331626].

The role of directional atherectomy in critical-limb ischemia

Background:

Our aim was to review the current literature of the use of directional atherectomy (DA) in the treatment of lower extremity critical-limb ischemia.

Methods:

A search for relevant literature was performed in PubMed and PubMed Central on 16 April 2020, sorted by best match. Three searches across two databases were performed. Articles were included that contained clinical and procedural data of DA interventions in lower extremity critical-limb ischemia patients. All studies that were systematic reviews were excluded.

Results:

Eleven papers were included in this review. Papers were examined under several parameters: primary patency and secondary patency, limb salvage/amputation, technical/procedural success, complications/periprocedural events, and mean lesion length. Primary and secondary patency rates ranged from 56.3% to 95.0% and 76.4% to 100%, respectively. Limb salvage rates ranged from 69% to 100%. Lesion lengths were highly varied, representing a broad population, ranging from 30 ± 33 mm to 142.4 ± 107.9 mm.

Conclusions:

DA may be a useful tool in the treatment of lower extremity critical-limb ischemia.

Analysis of Interwoven Nitinol Stenting for the Treatment of Critical Limb Ischemia: Outcomes From an Average 3-Year Follow-up Period

We assessed the clinical outcomes of patients with critical limb-threatening ischemia (CLTI) who underwent interwoven nitinol stent (Supera) implantation for significant stenoses of the femoropopliteal segment. In this retrospective cohort study, 116 consecutive patients with CLTI who were treated with Supera stents between September 2015 and March 2020 were included in this analysis. Primary endpoint analysis was completed for amputation-free survival, target lesion revascularization (TLR), and mortality. After a mean follow-up time of 3.4 years, 21 (18%) patients had undergone amputations, 3 (2.6%) died, and, overall, the amputation-free survival rate was 81%. TLR occurred in 21 (18%) patients, resulting in the freedom from target lesion revascularization of 82%. The average Wagner score for all patients was 2.8 ± 1.1. A subgroup analysis of 57 patients revealed a median ulcer size of 3.0 cm² [1.65, 9.0], with complete healing for 45 patients by 20 months. The Wagner score of this subgroup decreased by an average of 3.4 ± .9 points. Supera stents can be used together with other endovascular therapies and are a safe and effective treatment modality for CLTI.

Comprehensive Assessment of Current Management Strategies for Patients With Diabetes and Chronic Limb-Threatening Ischemia

Chronic limb-threatening ischemia (CLTI) is the most severe form of peripheral artery disease. It is estimated that 60% of all nontraumatic lower-extremity amputations performed annually in the United States are in patients with diabetes and CLTI. The consequences of this condition are extraordinary, with substantial patient morbidity and mortality and high socioeconomic costs. Strategies that optimize the success of arterial revascularization in this unique patient population can have a substantial public health impact and improve patient outcomes. This article provides an up-to-date comprehensive assessment of management strategies for patients afflicted by both diabetes and CLTI.

Comparison of femoro-popliteal plain balloon angioplasty for chronic limb threatening ischaemia in the BASIL trial and in a UK contemporary series

BACKGROUND

Since the turn of the millennium there has been a world-wide trend towards an endovascular first where possible revascularisation strategy for chronic limb threatening (CLTI). There is concern that this may be inappropriate and can result in net patient harm. The aim of this study, therefore, is to compare important clinical outcomes following femoro-popliteal plain balloon angioplasty (FP-PBA), with selective use of bare metal stents (BMS), in a contemporary series (CS) of patients treated in our unit between 2009 and 2014 with those observed following FP-PBA +/- BMS in the UK NIHR HTA-funded Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL-1, B1) trial (treated 1999-2004).

METHODS

Baseline and clinical outcome data (amputation free survival, AFS; overall survival, OS; limb salvage, LS; freedom from re-intervention, FF-R; freedom from major adverse limb events, FF-MALE) were obtained from prospectively gathered hospital data and B1 trial case record forms.

RESULTS

There were 237 CS and 218 B1 patients. CS patients were older (77 vs 73 years, p=.0002). B1 patients were more likely to be current smokers, less likely to be on best medical therapy, and underwent more extensive endovascular interventions. CS had more hospital admissions (4 vs 2, p<.0001) before they reached their primary endpoint (AFS). Immediate technical success was non-significantly higher in the CS patients (87% vs 83%, p=0.2). BMS were used in 20 (8%) CS and 2 (1%) B1 patients (p=.0002). AFS (HR = 0.64, 95%CI: 0.49 to 0.82, p = .0005) and OS (HR = 0.58, 95% CI: 0.44 to 0.76, p = .0001) were significantly worse in the CS cohort. There was no significant difference in LS, FF-R or FF-MALE.

CONCLUSIONS

CLTI patients managed in our unit (2009-2014) by means of a FP-PBA +/- BMS first where possible revascularisation strategy experience significantly worse AFS and OS than patients treated with FP-PBA +/- BMS in the B1 trial ten years earlier (1999-2004).

Anterior, posterior, or all-vessel infrapopliteal revascularization in patients with moderate-severe claudication: Insights from the LIBERTY 360 study

BACKGROUND

Little data guides revascularization of infrapopliteal peripheral arterial disease (PAD) in patients with claudication. We assessed outcomes after infrapopliteal-only intervention for claudication in the LIBERTY 360 observational study.

METHODS

In this post hoc analysis, LIBERTY 360 patients (N = 128) with claudication and isolated infrapopliteal disease undergoing endovascular revascularization were divided by territory into anterior-vessel, posterior-vessel, or all-vessel groups. Patients were followed for periprocedural, in-hospital, and long-term outcomes. Logistic regression for odds ratios, Cox proportional hazard models, ANOVA, and Kaplan-Meier estimates were utilized to compare outcomes.

RESULTS

Patients underwent anterior (N = 37), posterior (N = 76), or all-vessel (N = 15) infrapopliteal revascularization. Initial procedural success was 86%, 86%, and 69% for anterior, posterior, and all-vessel groups, respectively. Each group had improvements in Rutherford classification (RC) from baseline to 2 years (mean RC change: -1.3, -1.5, and -1.5, respectively). Compared with all-vessel intervention, both anterior and posterior groups had lower rate of major adverse events (MAE) and target vessel revascularization (TVR) at 3 years (MAE: 12% and 15% in anterior and posterior groups, respectively compared with 51% in the all-vessel group; hazard ratios and 95% CIs 0.22 [0.06-0.74], p = .015; 0.24 [0.09-0.64], p = .004). Other outcomes were similar among the three groups. The anterior group showed more improvement in pain subdomain and total VascuQoL scores compared with posterior and all-vessel groups at 2 years (p = .016, p = .020 and p = .068, p = .009, respectively).

CONCLUSIONS

Both anterior or posterior revascularization have favorable outcomes and may be beneficial for improvement of symptoms in claudicants with isolated infrapopliteal PAD.

Comparative performance analysis of interventional devices for the treatment of ischemic disease in below-the-knee lesions: a systematic review and meta-analysis

This meta-analysis aimed to evaluate the device performance of conventional balloon catheters (POBA), drug-coated balloons (DCB), bare-metal stents (BMS), and drug-eluting stents (DES) in below-the-knee (BTK) ischemic lesions with regard to lesion characteristics. Online searches of PubMed, Web of Science, and Cochrane databases (2010–2019) were conducted for each of the test devices. Primary patency rates (pp) and major amputation rates 1 year after the use of each device were analyzed using a random-effects meta-analysis model. Meta-regression analysis was conducted to test associations between the outcomes and lesion characteristics. The analysis included 18 studies reporting on 24 separate cohorts comprising 2,438 patients. DES demonstrated the best pp among the test devices (83.6%; 95% confidence interval = 78.4–88.8%, studies = 8; I² = 66%, P = 0.005). A negative coefficient between lesion length and pp (P = 0.002) was obtained. The ratio of critical limb ischemia (CLI) patients impacted the amputation rates (P = 0.031), whereas no statistically significant difference was found between the devices. DES showed favorable pp in BTK lesions; however, as the lesion lengths using DES were short, pp in long lesions still needs to be evaluated. Shorter lesions gained better pp. A higher ratio of CLI patients resulted in increased amputation rates.

Asia-Pacific Consensus Statement on the Management of Peripheral Artery Disease: A Report from the Asian Pacific Society of Atherosclerosis and Vascular Disease Asia-Pacific Peripheral Artery Disease Consensus Statement Project Committee

BACKGROUND

Peripheral artery disease (PAD) is the most underdiagnosed, underestimated and undertreated of the atherosclerotic vascular diseases despite its poor prognosis. There may be racial or contextual differences in the Asia-Pacific region as to epidemiology, availability of diagnostic and therapeutic modalities, and even patient treatment response. The Asian Pacific Society of Atherosclerosis and Vascular Diseases (APSAVD) thus coordinated the development of an Asia-Pacific Consensus Statement (APCS) on the Management of PAD.

OBJECTIVES

The APSAVD aimed to accomplish the following: 1) determine the applicability of the 2016 AHA/ACC guidelines on the Management of Patients with Lower Extremity Peripheral Artery Disease to the Asia-Pacific region; 2) review Asia-Pacific literature; and 3) increase the awareness of PAD.

METHODOLOGY

A Steering Committee was organized to oversee development of the APCS, appoint a Technical Working Group (TWG) and Consensus Panel (CP). The TWG appraised the relevance of the 2016 AHA/ACC PAD Guideline and proposed recommendations which were reviewed by the CP using a modified Delphi technique.

RESULTS

A total of 91 recommendations were generated covering history and physical examination, diagnosis, and treatment of PAD-3 new recommendations, 31 adaptations and 57 adopted statements. This Asia-Pacific Consensus Statement on the Management of PAD constitutes the first for the Asia-Pacific Region. It is intended for use by health practitioners involved in preventing, diagnosing and treating patients with PAD and ultimately the patients and their families themselves.

Mortality in patients undergoing revascularization with paclitaxel eluting devices for infrainguinal peripheral artery disease: Insights from a network meta-analysis of randomized trials

OBJECTIVES

We aimed to evaluate whether paclitaxel eluting devices increased the risk of death in patients undergoing revascularization for infrainguinal peripheral artery disease using network meta-analyses.

METHODS

PUBMED and EMBASE were searched through April 2020 for randomized trials in patients with infrainguinal peripheral artery disease who underwent revascularization with or without a paclitaxel eluting device (balloon/stent). Short-term mortality defined as death at 6-12 months, and long-term mortality defined as death at >12 months after revascularization.

RESULTS

Our search identified 57 eligible randomized controlled studies enrolling a total of 9,362 patients comparing seven revascularization strategies (balloon angioplasty vs. bare metal stent vs. covered stent vs. paclitaxel eluting stent vs. other drug eluting stent vs. paclitaxel-coated balloon vs. bypass surgery). Overall, paclitaxel eluting stent and paclitaxel-coated balloons did not increase short-term mortality (eg, vs. balloon angioplasty: paclitaxel-coated balloon OR [95% CI] 1.21 [0.88-1.66], p = .24; paclitaxel eluting stent OR [95%CI] 1.01 [0.63-1.63], p = .97, respectively). In addition, paclitaxel eluting stent did not show significant increase in long-term mortality (eg, vs. balloon angioplasty: OR [95%CI] 1.06 [0.70-1.59], p = .79). However, paclitaxel-coated balloon showed significant increase in long-term mortality compared to balloon angioplasty and bypass (vs. balloon angioplasty: OR [95% CI] 1.48 [1.06-2.07], p = .021; vs. bypass: OR [95%CI] 1.73 [1.05-2.84], p = .031, respectively).

CONCLUSIONS

In this meta-analysis of randomized trials, there was no significant increase in mortality with paclitaxel eluting stent, but there was increased risk of long-term mortality in paclitaxel-coated balloon for the treatment of infrainguinal peripheral artery disease.

Antiplatelet and Anticoagulant Use in Randomised Trials of Patients Undergoing Endovascular Intervention for Peripheral Arterial Disease: Systematic Review and Narrative Synthesis

OBJECTIVE

Randomised trials of new devices for peripheral arterial endovascular intervention are published regularly. The evidence for which antiplatelet and/or anticoagulant (antithrombotic) therapy to use after an intervention is lacking. The aim of this systematic review was to examine the antithrombotic regimens in randomised trials for peripheral arterial endovascular intervention to understand choices made and trends with time or type of device.

METHODS

Data sources were the Medline, Embase, and Cochrane Library databases. Randomised trials including participants with peripheral arterial disease undergoing any endovascular arterial intervention were included. Trial methods were assessed to determine whether an antithrombotic protocol had been specified, its completeness, and the agent(s) prescribed. Antithrombotic therapy protocols were classed as peri-procedural (preceding and during intervention), immediate post-procedural (up to 30 days following intervention), and maintenance post-procedural (therapy continuing beyond 30 days).

RESULTS

Ninety-four trials were included in narrative synthesis. Study quality was low. None of the trials justified their antithrombotic therapy protocol. Only 29% of trials had complete peri-procedural antithrombotic protocols, and 34% had complete post-procedural protocols. In total, 64 different peri-procedural protocols, and 51 separate post-procedural protocols were specified. Antiplatelet monotherapy and unfractionated heparin were the most common regimen choices in the peri-procedural setting, and dual antiplatelet therapy (55%) was most commonly utilised post procedure. Over time there has been an increasing tendency to use dual therapy (p < .001). This corresponds with the introduction of newer technologies and trials focussed on below knee intervention.

CONCLUSION

Randomised trials comparing different types of peripheral endovascular arterial intervention have a high level of heterogeneity in their antithrombotic regimens. Antiplatelet therapy needs to be standardised in trials comparing endovascular technologies to reduce potential confounding. To do this, an independent randomised trial specifically examining antiplatelet therapy following peripheral arterial endovascular intervention is needed.

Balloon Angioplasty of Infrapopliteal Arteries: A Systematic Review and Proposed Algorithm for Optimal Endovascular Therapy

Endovascular revascularization has been increasingly utilized to treat patients with chronic limb-threatening ischemia (CLTI), particularly atherosclerotic disease in the infrapopliteal arteries. Lesions of the infrapopliteal arteries are the result of 2 different etiologies: medial calcification and intimal atheromatous plaque. Although several devices are available for endovascular treatment of infrapopliteal lesions, balloon angioplasty still comprises the mainstay of therapy due to a lack of purpose-built devices. The mechanism of balloon angioplasty consists of adventitial stretching, medial necrosis, and dissection or plaque fracture. In many cases, the diffuse nature of infrapopliteal disease and plaque complexity may lead to dissection, recoil, and early restenosis. Optimal balloon angioplasty requires careful attention to assessment of vessel calcification, appropriate vessel sizing, and the use of long balloons with prolonged inflation times, as outlined in a treatment algorithm based on this systematic review. Further development of specific devices for this arterial segment are warranted, including devices for preventing recoil (eg, dedicated atherectomy devices), treating dissections (eg, tacks, stents), and preventing neointimal hyperplasia (eg, novel drug delivery techniques and drug-eluting stents). Further understanding of infrapopliteal disease, along with the development of new technologies, will help optimize the durability of endovascular interventions and ultimately improve the limb-related outcomes of patients with CLTI.

Diagnostic and Therapeutic Approaches in the Management of Infrapopliteal Arterial Disease

Chronic limb-threatening ischemia represents end-stage peripheral artery disease. It is underdiagnosed; it relies on clinical symptoms and traditional noninvasive tests, which significantly underestimate the severity of disease. Innovative techniques, approaches, technologies, and risk-assessment tools have significantly improved our ability to treat these patients and to better understand their complex disease process. For patients with chronic limb-threatening ischemia considered without options, the reengineering of deep venous arterialization procedures has shown promising results. Finally, the creation of interactive and multidisciplinary teams in centers of excellence is of paramount importance to significantly improve the care and outcomes of these patients.

Angioplasty versus stenting for infrapopliteal arterial lesions in chronic limb-threatening ischaemia

BACKGROUND

Chronic limb-threatening ischaemia (CLTI) is a manifestation of peripheral arterial disease (PAD) that includes chronic ischaemic rest pain or ischaemic skin lesions, ulcers, or gangrene for longer than two weeks. The severity of the disease depends on the extent of arterial stenosis and the availability of collateral circulation. Treatment for CLTI aims to relieve ischaemic pain, heal ischaemic ulcers, prevent limb loss, improve quality of life, and prolong survival. CLTI due to occlusive disease in the infrapopliteal arterial circulation (below-knee circulation) can be treated via an endovascular technique by a balloon opening the narrowed vessel, so called angioplasty, with or without the additional deployment of a scaffold made of metal alloy or other material, so called stenting. Endovascular interventions in the infrapopliteal vasculature may improve symptoms in patients with CLTI by re-establishing in-line blood flow to the foot. Controversy remains as to whether a balloon should be used alone to open the vessel, or whether a stent should also be deployed.

OBJECTIVES

To determine the efficacy and safety of percutaneous transluminal angioplasty (PTA) alone versus PTA with stenting of infrapopliteal arterial lesions (anterior tibial artery, posterior tibial artery, fibular artery (formerly known as peroneal artery), and common tibioperoneal trunk) for patients with chronic limb-threatening ischaemia (CLTI).

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, and AMED databases, as well as World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 25 June 2018. We applied no language restrictions.

SELECTION CRITERIA

We planned to include randomised or quasi-randomised controlled trials comparing PTA versus PTA with a stent and including patients aged 18 years or over with CLTI. We defined CLTI as Fontaine stage III (ischaemic rest pain) and IV (ischaemic ulcers or gangrene) or consistent with Rutherford category 4 (ischaemic rest pain), 5 (minor tissue loss), and 6 (major tissue loss), with stenotic (> 50% luminal loss) or occluded infrapopliteal artery, including tibiofibular trunk, anterior tibial artery, posterior tibial artery, and fibular artery. We included all types of stents irrespective of design (e.g. bare-metal, drug-eluting, bio-absorbable).

DATA COLLECTION AND ANALYSIS

Two review authors (CC-TH and GNCK) independently selected suitable trials, assessed trial quality, and extracted data. An additional third review author (MLvD) assessed trial quality and, when necessary, acted as arbiter for study selection and data extraction. Outcomes included technical success of the procedure, procedural complications, patency, major amputation, and mortality. We assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

We included in the review seven trials with 542 participants. One trial randomised limbs to undergo PTA alone or PTA with stent placement, and the remaining studies randomised participants. Five trials with 476 participants show that the technical success rate was greater in the stent group than in the angioplasty group (odds ratio (OR) 3.00, 95% confidence interval (CI) 1.14 to 7.93; 476 lesions; 5 studies; I² = 23%). Meta-analysis of three eligible trials with 456 participants did not show a clear difference in short-term (within six months) patency between infrapopliteal arterial lesions treated with PTA and those treated with PTA and stenting (OR 0.88, 95% CI 0.37 to 2.11; 456 lesions; 3 studies; I² = 77%). Results also did not show clear differences between treatment groups in procedure complication rate (OR 0.87, 95% CI 0.01 to 53.60; 360 participants; 5 studies; I² = 85%), rate of major amputations at 12 months (OR 1.34, 95% CI 0.56 to 3.22; 306 participants; 4 studies; I² = 0%), and rate of mortality at 12 months (OR 0.71, 95% CI 0.43 to 1.17; 497 participants; 6 studies; I² = 0%). Heterogeneity between studies was high for the outcomes procedure complications and primary patency. The overall methodological quality of the trials included in this review was moderate due to selection and performance bias. Studies used different regimens for pretreatment and post-treatment antiplatelet/anticoagulant medication. We downgraded the certainty of the overall evidence for all outcomes by one level to moderate due to inconsistency of results across studies and large confidence intervals (small numbers of trials and participants).

AUTHORS' CONCLUSIONS

Trials show that the immediate technical success rate of restoring luminal patency is higher in the stent group but reveal no clear differences in short-term patency at six months between infrapopliteal arterial lesions treated with PTA with stenting versus those treated with PTA without stenting. We ascertained no clear differences between groups in periprocedural complications, major amputation, and mortality. However, use of different regimens for pretreatment and post-treatment antiplatelet/anticoagulant medication and the duration of its use within and between trials may have influenced the outcomes. Limited currently available data suggest that high-quality evidence is insufficient to show that PTA with stent insertion is superior to use of standard PTA alone without stenting for treatment of infrapopliteal arterial lesions. Further studies should standardise the use of antiplatelets/anticoagulants before and after the intervention to improve the comparability of the two treatments.

The Contemporary Role of Stents and Angioplasty for the Treatment of Infrapopliteal Disease in Critical Limb Ischemia

PURPOSE OF REVIEW

Critical limb ischemia (CLI) is associated with significant morbidity, mortality, and increased health care expenses. Revascularization has a central role in the treatment of CLI. Following publication of BASIL (bypass versus angioplasty in severe ischemia of the leg) trial a decade ago, an "endovascular first" approach had gained momentum and the technologies available for endovascular therapy have exponentially increased. Both the development of technology and technique, highlighted in this review, have allowed operators to treat complex infrapopliteal lesions which are central to CLI pathology.

RECENT FINDINGS

The role of atherectomy remains controversial but for calcified lesions it has become an accepted adjunctive tool for plaque modification. The place of drug delivery technologies requires further trials. The use of a drug-coated balloon (DCB) makes intuitive sense; however, choice of excipient, lower limit of vessel size, and impact on remodeling and thrombosis remain uncertain. The optimal treatment of infrapopliteal disease remains an area of active investigation. The endpoints in CLI trials continue to be challenging and calibration of patency in relation to wound healing remains a moving target. In addition, unaccounted variables continue to confound interpretation of CLI trials-including quality and nature of wound care, status of pedal-plantar loop patency, and management of underlying diabetes and other comorbidities. In summary, these challenges will also need to be addressed as the CLI field continues to mature in the twenty-first century.

2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines with recommendations to improve cardiovascular health. These guidelines, based on systematic methods to evaluate and classify evidence, provide a cornerstone of quality cardiovascular care.

In response to reports from the Institute of Medicine1 ,2 and a mandate to evaluate new knowledge and maintain relevance at the point of care, the ACC/AHA Task Force on Clinical Practice Guidelines (Task Force) modified its methodology.3 –5 The relationships among guidelines, data standards, appropriate use criteria, and performance measures are addressed elsewhere.5

2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines with recommendations to improve cardiovascular health. These guidelines, based on systematic methods to evaluate and classify evidence, provide a cornerstone of quality cardiovascular care.

In response to reports from the Institute of Medicine1 ,2 and a mandate to evaluate new knowledge and maintain relevance at the point of care, the ACC/AHA Task Force on Clinical Practice Guidelines (Task Force) modified its methodology.3 –5 The relationships among guidelines, data standards, appropriate use criteria, and performance measures are addressed elsewhere.5

Comparative Effectiveness of Plain Balloon Angioplasty, Bare Metal Stents, Drug-Coated Balloons, and Drug-Eluting Stents for the Treatment of Infrapopliteal Artery Disease: Systematic Review and Bayesian Network Meta-analysis of Randomized Controlled Trials

PURPOSE

To report a Bayesian network meta-analysis of randomized controlled trials (RCTs) comparing bare metal stents (BMS), paclitaxel-coated balloons (PCBs), and drug-eluting stents (DES) with balloon angioplasty (BA) or with each other in the infrapopliteal arteries.

METHODS

Sixteen RCTs comprising 1805 patients with 1-year median follow-up were analyzed. Bayesian random effects binomial models were employed (WinBUGS). Relative treatment effects were expressed as odds ratios (ORs) with 95% credible intervals (CrI), and the cumulative rank probabilities were calculated to provide hierarchies of competing treatments. Quality of evidence (QoE) was assessed with the GRADE (grading of recommendations assessment, development, and evaluation) system. Sensitivity, heterogeneity, and consistency analyses were performed.

RESULTS

There was high QoE that infrapopliteal DES significantly reduced restenosis compared with BMS (OR 0.26, 95% CrI 0.12 to 0.51) and BA (OR 0.22, 95% CrI 0.11 to 0.45). Likewise, DES significantly reduced target lesion revascularization (TLR) compared with BA (OR 0.41, 95% CrI 0.22 to 0.75) and BMS (OR 0.26, 95% CrI 0.15 to 0.45). Paclitaxel-coated balloons also reduced TLR compared with BA (OR 0.55, 95% CrI 0.34 to 0.90) and BMS (OR 0.35, 95% CrI 0.18 to 0.67), but QoE was low to moderate. BA had lower TLR than BMS (OR 0.63, 95% CrI 0.40 to 0.99) with high QoE. DES was the only treatment that significantly reduced limb amputations compared with BA (OR 0.58, 95% CrI 0.35 to 0.96), PCB (OR 0.51, 95% CrI 0.26 to 0.98), or BMS (OR 0.38, 95% CrI 0.19 to 0.72) with moderate to high QoE. DES also significantly improved wound healing compared with BA (OR 2.02, 95% CrI 1.01 to 4.07) or BMS (OR 3.45, 95% CrI 1.41 to 8.73) with high QoE. Results were stable on sensitivity and meta-regression analyses without any significant publication bias or inconsistency.

CONCLUSION

Infrapopliteal DES were associated with significantly lower rates of restenosis, TLR, and amputations and improved wound healing compared to BA and BMS. DES also significantly reduced amputations compared with PCB.

[Treatment of below the knee lesions: Broadening the limits of vascular surgery]

One third of patients with critical limb ischemia (CLI) has below the knee lesions and requires a restoration of direct blood flow into the foot. However, many of these patients are ineligible for open surgery. The primary goals thus become pain relief and limb salvage over patency. The angiosome concept helps determine the target artery to treat in priority. The endovascular approach has decreased morbidity and mortality rates compared to distal bypass surgery; while subintimal retrograde, trans-collateral and loop techniques push the limits of open surgery by reopening the plantar arch, thereby improving run-off. Early restenosis phenomena after angioplasty have been improved by the use of - limus drug eluting balloons and balloon expandable stents in case of flow limiting dissection or recoil with increased limb salvage rates. Moreover, drug-eluting stents have been proposed, and allow a reduction in reintervention and in-stent restenosis rates in short lesions; however, results on amputation rates or survival are limited. Vessel preparation is a key to overcoming some current limitations, including atherectomy, which increases technical success rates and reduces restenosis rates, especially in calcified lesions, chronic total occlusions and restenosis. These advanced techniques in distal endovascular revascularization have revolutionized limb salvage and support the interest of an endovascular first approach in CLI treatment.

Single-Center Experience With Lutonix Drug-Coated Balloons in Infrapopliteal Arteries

Purpose: To examine patient outcomes following the use of the Lutonix drug-coated balloon (DCB) in patients undergoing endovascular intervention in below-the-knee (BTK) arteries. Methods: A retrospective chart review identified 248 patients who were treated for symptomatic peripheral artery disease with the Lutonix DCB between May 2013 and October 2014. Forty patients were lost to follow-up, leaving 208 patients (mean age 74.1±9.7 years; 138 men) with evaluable data for outcome analysis. The patient cohort suffered from either severe claudication (38.6%) or critical limb ischemia (CLI; 61.4%) in 220 limbs. Almost two-thirds (140, 63.6%) of the 220 target lesions were total occlusions, and 37 (17.8%) of all patients had occlusion of all 3 BTK vessels before intervention. Results: Over a median 9-month follow-up, target lesion revascularization occurred in 15.9% of patients with an average time to first reintervention of 8 months. In total, 39 amputations were performed in 31 limbs. However, 17 of these amputations were preplanned minor amputations below the ankle; only 9 (4.1%) major amputations occurred corresponding to 6.6% of the CLI cohort. Freedom from the composite of death or major amputation was estimated as 92% and 85% at 6 and 12 months, respectively, by Kaplan-Meier analysis. In the full cohort, improvement of at least 1 Rutherford category was seen in 130 (59.1%) limbs after 1 year or at the last follow-up, with 104 (80.0%) of those limbs showing an improvement of ≥2 categories. Conclusion: From this single-center experience, the Lutonix DCB shows therapeutic promise in a disease state where new treatment options are needed.

Endovascular Treatment of Infrapopliteal Peripheral Artery Disease

Endovascular treatment of infrapopliteal disease is focused on the treatment of patients with rest pain or critical limb ischemia (CLI) due to severe atherosclerotic disease. While the evidence base surrounding the comparative effectiveness of endovascular intervention vs. surgery is lacking, many operators have adopted an "endovascular first" approach to the treatment of infrapopliteal atherosclerotic disease due to the lower morbidity of these procedures. This manuscript reviews current data on the endovascular treatment of CLI, including a comparison of endovascular and surgical approaches, current indications for and outcomes with balloon angioplasty of infrapopliteal PAD, angiosome-guided revascularization, and emerging technologies to improve long-term vessel patency after endovascular intervention.