PTA Versus Carbofilm-Coated Stents in Infrapopliteal Arteries: Pilot Study

Network Meta-analysis of Randomised Controlled Trials Comparing the Outcomes of Different Endovascular Revascularisation Treatments for Infra-inguinal Peripheral Arterial Disease Causing Chronic Limb Threatening Ischaemia

OBJECTIVE

The aim of this study was to compare the efficacy of different endovascular revascularisation procedures for treating chronic limb threatening ischaemia (CLTI) using network meta-analysis (NMA).

DATA SOURCES

The databases PubMed and Cochrane Central Register for Controlled Trials were searched on 14 March 2023.

REVIEW METHODS

A NMA of randomised controlled trials (RCTs) reporting the efficacy of different endovascular revascularisation techniques for treating CLTI was performed according to PRISMA guidelines. The primary and secondary outcomes were major amputation and death, respectively. Random effects models were developed and the results were presented using surface under the cumulative ranking curve plots and forest plots. A p value of ≤ .050 was considered statistically significant. The Cochrane collaborative tool was used to assess risk of bias.

RESULTS

A total of 2 655 participants of whom 94.8% had CLTI were included. Eleven trials compared plain balloon angioplasty (PBA) vs. drug coated balloon (DCB) angioplasty (n = 1 771), five trials compared bare metal stent (BMS) vs. drug coated stent (DCS) (n = 466), three trials compared atherectomy vs. DCB (n = 194), two trials compared PBA vs. BMS (n = 70), one trial compared PBA vs. atherectomy (n = 50), and one trial compared BMS vs. DCB (n = 104). None of the revascularisation strategies significantly reduced the risk of major amputation or death compared with PBA. Using the network estimates, GRADE certainty of evidence for improvement in major amputation outcomes for DCB was moderate, for atherectomy and BMS was low, and for DCS was very low compared with PBA. Risk of bias was low in 16 trials, of some concerns in six trials, and high in one trial, respectively.

CONCLUSION

There is no current evidence from RCTs to reliably conclude that BMS, DCB, DCS, or atherectomy are superior to PBA in preventing major amputation and death in patients with CLTI. Larger comparative RCTs are needed to identify the best endovascular revascularisation strategy.

Percutaneous Transluminal Angioplasty for Infrapopliteal Chronic Limb-Threatening Ischemia: A Systematic Review and Meta-analysis of Primary Patency and Binary Restenosis Rates

PURPOSE

Percutaneous transluminal angioplasty (PTA) remains the mainstay of endovascular therapy for infrapopliteal chronic limb-threatening ischemia (CLTI), but outcomes have not been well characterized using high-quality data. The aim of this meta-analysis was to provide an updated benchmark for rates of primary patency and binary restenosis after PTA using prospectively collected, predominantly core-lab adjudicated randomized controlled trial (RCT) data.

MATERIALS AND METHODS

MEDLINE, EMBASE, Cochrane Central, and ClinicalTrials.gov were queried for RCTs published through November 2022 using PTA as a control arm and including patients with infrapopliteal CLTI. Studies were excluded if >25% of patients had intermittent claudication, other vessels were included, or primary patency or binary restenosis were not outcomes. Outcomes were analyzed using random effects models. This analysis was publicly registered (PROSPERO ID#394543). No funding was utilized.

RESULTS

Seventeen RCTs were included (1048 patients, 1279 lesions). Pooled primary patency rates using data from 6 RCTs were 68% at 6 months (95% confidence interval [CI]=45%-84%) and 66% at 12 months (95% CI=51%-79%). Pooled binary restenosis rates using data from 11 RCTs were 54% at 6 months (95% CI=33%-73%) and 60% at 9 to 12 months (95% CI=39%-78%). Significant heterogeneity was present in all outcomes (I2>50%, p<0.0001). Publication bias was not observed (Egger's p>0.1).

CONCLUSIONS

This meta-analysis provides estimates for binary restenosis and primary patency following PTA utilizing prospectively collected, predominantly core-lab adjudicated data. Results demonstrate 1-year primary patency rates that are 10% to 20% higher than what has been historically used in power calculations. These new estimates will help facilitate more accurate power analysis for future RCTs.

CLINICAL IMPACT

Rates of primary patency and binary restenosis after percutaneous transluminal angioplasty (PTA) have not been well-described using high-quality data, and investigators have been utilizing estimates of 40% to 50% and 45% to 65%, respectively, when performing power calculations for trials. This meta-analysis demonstrates using high-quality, prospectively collected, and predominantly core-lab adjudicated randomized controlled trial data that actual rates of primary patency are closer to 60% up to 1 year following PTA and provides the first meta-analysis estimate of binary restenosis rates up to 1 year after PTA. These estimates will help facilitate more accurate power calculations for future RCTs in this space.

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].

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.

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.

Network meta-analysis of balloon angioplasty, nondrug metal stent, drug-eluting balloon, and drug-eluting stent for treatment of infrapopliteal artery occlusive disease

PURPOSE

We aimed to conduct a network meta-analysis of mixed treatments for the infrapopliteal artery occlusive disease.

METHODS

We searched randomized controlled trials (RCTs) regarding balloon angioplasty (BA), nondrug metal stent (NDMS), drug-eluting balloon (DEB), or drug-eluting stent (DES) in PubMed, Embase, CENTRAL, Ovid, Sinomed, and other relevant websites. We selected and assessed the trials that met the inclusion criteria and conducted a network meta-analysis using the ADDIS software.

RESULTS

We included 11 relevant trials. We analyzed data of 1322 patients with infrapopliteal artery occlusive disease, of which 351 were in the NDMS vs. DES trials, 231 in the NDMS vs. BA trials, 490 in the BA vs. DEB trials, 50 in the DEB vs. DES trials, and 200 in the BA vs. DES trials. The network meta-analysis indicated that with NDMS as the reference, DES had a better result with respect to restenosis (odds ratio [OR], 5.16; 95% credible interval [CI], 1.58-18.41; probability of the best treatment, 84%) and amputation (OR, 2.50; 95% CI, 0.81-7.11; probability of the best treatment, 61%) and DEB had a better result with respect to target lesion revascularization (TLR; OR, 3.74; 95% CI, 0.78-17.05; probability of the best treatment, 57%). Moreover, with BA as the reference, NDMS had a better result with respect to technical success (OR, 0.10; 95% CI, 0.00-1.15; probability of the best treatment, 86%).

CONCLUSION

Our meta-analysis revealed that DES is a better treatment with respect to short-term patency and limb salvage rate, NMDS may provide a better technical success, and DEB and DES are good choices for reducing revascularization.

Systematic Review and Meta-Analysis of Drug-Eluting Balloon and Stent for Infrapopliteal Artery Revascularization

Background:

Drug-eluting balloon (DEB) and drug-eluting stent (DES) have been proposed for the treatment of infrapopliteal artery disease. We performed a systematic review and meta-analysis of the current available studies investigating outcomes of DEB and DES in the treatment of infrapopliteal artery disease.

Methods:

Multiple databases were systematically searched to identify studies investigating the outcomes of DEB and DES in the treatment of patients with infrapopliteal artery disease. The quality of studies was assessed by Cochrane Collaboration method. The demographic data, risk factors, outcomes, and antiplatelet strategy were extracted.

Results:

Nine studies were identified with 707 and 606 patients in DEB/DES and standard percutaneous balloon angioplasty (PTA)/bare metal stenting (BMS) group, respectively. The risk of target lesion revascularization (TLR; odds ratio [OR] = 0.38, 95% confidence interval [CI]: 0.23-0.63, P < .01), restenosis rate (OR = 0.30, 95% CI: 0.18-0.50, P < .01), and amputation rate (OR = 0.49, 95% CI: 0.29-0.83, P < .01) significantly decreased in the DES group. The overall survival (OR = 0.86, 95% CI: 0.56-1.32, P = .50) was similar in DES and standard PTA/BMS group; TLR (OR = 0.59, 95% CI: 0.32-1.09, P = .09), restenosis rate (OR = 0.49, 95% CI: 0.11-2.14, P = .35), amputation rate (OR = 1.32, 95% CI: 0.51-3.40, P = .57), and overall survival (OR = 1.40, 95% CI: 0.72-2.71, P = .32) were similar in DEB and standard PTA group.

Conclusion:

The present meta-analysis suggests that compared with standard PTA/BMS, DES may decrease the risk of clinically driven TLR, restenosis rate, and amputation rate without any impact on mortality. However, DEB has no obvious advantage in the treatment of infrapopliteal disease. Due to the limitations of our study, more randomized controlled trials, especially those for DEB, are necessary.

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.

Two-Year Results after Directional Atherectomy of Infrapopliteal Arteries with the SilverHawk Device

Purpose:

To report the 12- and 24-month results after directional atherectomy (DA) of below-the-knee (BTK) arterial lesions with the SilverHawk device.

Methods:

Forty-nine BTK lesions in 36 patients (58% men; mean age 70611 years) with peripheral occlusive disease of the lower limbs were treated with DA; 19 (53%) of the limbs were classified with Rutherford-Becker 4 or 5 ischemia. Target lesions were in the popliteal artery (n=6, 12%), tibioperoneal trunk (n=25, 51%), peroneal artery (n=10, 20%), anterior tibial artery (n=5, 10%), and posterior tibial artery (n=3, 6%). Nine (18%) lesions were located in a stent. Twelve lesions extended to 2 artery segments. The average degree of diameter stenosis was 89%±10% (range 70%–100%); there were 11 (22%) occlusions. The mean lesion length was 48±28 mm.

Results:

Sixteen (33%) lesions were treated after predilation; 33 (67%) lesions were treated with primary DA. All but 1 (2%) lesion could be treated with DA. In 19 (39%) lesions, additional balloon angioplasty was performed, and 2 (4%) lesions required stent implantation as a result of dissection. The mean stenosis diameter after DA was 12%±18% (range 0%–100%). After additional therapy, the mean stenosis diameter was 8%±9% (range 0%–100%). A residual stenosis ≤30% was achieved in 48 (98%) lesions. The mean ankle-brachial index significantly increased from 0.48±0.26 to 0.81±0.32 (p<0.05) before discharge and remained improved during follow-up. Primary and secondary patency rates were 67% and 91% after 1 year and 60% and 80% after 24 months. The 12-and 24-month cumulative event-free survival rates (primary patency) by Kaplan-Meier analysis were 58%±8% and 46%±9%; at the same time intervals, the cumulative survival rates (secondary patency) were 88%±6% and 73%±9%, respectively.

Conclusion:

BTK lesions can be treated successfully and safely with DA. Midterm clinical results are encouraging.

National trends for the treatment of peripheral arterial disease in Korea between 2004 and 2013

Purpose

Peripheral arterial disease (PAD) has been a major public health issue in the elderly. Advances in endovascular surgery have led to a substantial shift in the management of PAD. Although the nationwide trend of PAD treatment in the Western countries was reported, limited data have been available on this in Korea. This study examined the national trend in the treatment of PAD in Korea over the past decade.

Methods

Health Insurance Review and Assessment Service data were used. We sought to analyze trends in the open and endovascular surgery for the treatment of PAD in Medicare beneficiaries between 2004 and 2013. We also analyzed trends in each types of surgery in the lower extremity. A linear-by-linear association was performed to determine the changes of PAD treatment for this period.

Results

The rate of open surgery per 100,000 Medicare beneficiaries decreased significantly from 8 procedures in 2004 to 6 in 2013. At the same time, endovascular surgery increased from 23 procedures in 2004 to 59 in 2013. Endovascular surgery in the lower extremity increased more than twofold, while the open surgery decreased by 39%. The rate of balloon angioplasty among endovascular surgery was increased by almost threefold, while the bypass surgery using artificial graft decreased by half.

Conclusion

Endovascular surgery is now performed more commonly than open surgery for PAD treatment. Balloon angioplasty increased by almost threefold, while the bypass surgery using artificial graft decreased by about 50%.

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.

The Importance of Patency in Patients with Critical Limb Ischemia Undergoing Endovascular Revascularization for Infrapopliteal Arterial Disease

Critical limb ischemia (CLI) represents the most severe form of peripheral arterial disease (PAD) and frequently occurs in medically frail patients. CLI patients frequently exhibit multi-segmental PAD commonly including the tibial arterial segment. Endovascular therapy has been established as first-line revascularization strategy for most CLI patients. Restenosis was reported to occur in up to more than two-thirds of CLI patients undergoing angioplasty of complex tibial arterial obstructions. Nevertheless, favorable clinical outcomes were observed for infrapopliteal angioplasty when compared with bypass surgery, despite higher patency rates for the latter. Based on these observations, infrapopliteal patency was considered to be only of secondary importance upon clinical outcomes in CLI patients. In contrast to these earlier observations, however, recent findings from two randomized clinical trials indicate that infrapopliteal patency does impact on clinical outcomes in CLI patients. The purpose of the present manuscript is to provide a critical reappraisal of the present literature on the clinical importance of tibial arterial patency in CLI patients undergoing endovascular revascularization and to discuss utility and limitations of currently available anti-restenosis technologies.

Use of the Wallstent for infrapopliteal arterial disease and varying vessel diameters

There is little description of the Wallstent to treat infrapopliteal arterial disease. This may be a viable option due to its high conformability and ability to elongate in vessels of varying diameters. This case report highlights its use in this clinical situation.

Drug-eluting stents for revascularization of infrapopliteal arteries: updated meta-analysis of randomized trials

OBJECTIVES

This study sought to undertake an updated meta-analysis of randomized trials investigating the outcomes of percutaneous revascularization with primary drug-eluting stenting in patients with atherosclerotic disease of infrapopliteal arteries.

BACKGROUND

In atherosclerotic disease of infrapopliteal arteries, drug-eluting stents (DESs) improve patency rates compared with plain balloon angioplasty or bare-metal stents (BMSs). However, the clinical impact of DES placement in this vascular territory still remains uncertain.

METHODS

We searched MEDLINE, Embase, CENTRAL (Cochrane Central Register of Controlled Trials), scientific session abstracts, and relevant Websites. The keywords used were "below the knee," "infrapopliteal artery," "angioplasty," "drug-eluting stent(s)," "bare metal stent(s)," "trial," and "randomized trial." Inclusion criteria were randomized design, intention-to-treat analysis, and a minimum of 6-month follow-up. Exclusion criteria were vessels treated other than infrapopliteal arteries; devices used other than DESs, plain balloons, or BMSs; and duplicated data. The primary endpoint was target lesion revascularization; secondary endpoints were restenosis, amputation, death, and improvement in Rutherford class.

RESULTS

A total of 611 patients from 5 trials were randomly assigned to DESs (n = 294) versus control therapy (plain balloon angioplasty/BMS implantation, n = 307). Overall, the median lesion length was 26.8 mm (interquartile range [IQR]: 18.2 to 30.0 mm) with a reference vessel diameter of 2.86 mm (IQR: 2.68 to 3.00 mm). At a median follow-up of 12 months (IQR: 12 to 36 months), DESs reduced the risk of target lesion revascularization (odds ratio [OR]: 0.31; 95% confidence interval [CI]: 0.18 to 0.54; p < 0.001), restenosis (OR: 0.25; 95% CI: 0.15 to 0.43; p < 0.001), and amputation (OR: 0.50; 95% CI: 0.26 to 0.97); p = 0.04) without a significant difference in terms of death (OR: 0.81; 95% CI: 0.45 to 1.49; p = 0.50) and Rutherford class improvement (OR: 1.36; 95% CI: 0.91 to 2.04; p = 0.13) versus control therapy.

CONCLUSIONS

In focal disease of infrapopliteal arteries, DES therapy reduces the risk of reintervention and amputation compared with plain balloon angioplasty or BMS implantation without any impact on mortality and Rutherford class at 1-year follow-up.

Percutaneous transluminal angioplasty versus primary stenting in infrapopliteal arterial disease: a meta-analysis of randomized trials

BACKGROUND

Percutaneous transluminal angioplasty (PTA) and primary stenting are commonly used endovascular therapeutic procedures for the treatment of infrapopliteal arterial occlusive disease. However, which procedure is more beneficial for patients with infrapopliteal arterial occlusive disease is unknown.

METHODS AND RESULTS

We performed a meta-analysis, searching PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, ISI Web of Knowledge, and relevant websites without language or publication date restrictions for randomized trials that compared primary stenting with PTA in patients with infrapopliteal arterial occlusive disease. The keywords were "stents," "angioplasty," "infrapopliteal," "tibial arteries," and "below knee." We selected immediate technical success, primary and secondary patency, limb salvage, and patient survival as the outcomes of this meta-analysis. On the basis of the inclusion criteria, we identified six prospective randomized trials. One-year outcomes did not show any significant differences between the PTA and primary stenting groups, respectively: technical success (93.3% vs 96.2%; odds ratio [OR], 0.59; 95% confidence interval [CI], 0.24-1.47; P = .25), primary patency (57.1% vs 65.7%; OR, 0.95; 95% CI, 0.35-2.58; P = .92), secondary patency (73.5% vs 57.6%; OR, 2.08; 95% CI, 0.81-5.34; P = .13), limb salvage (82.2% vs 87.5%; OR, 0.64; 95% CI, 0.29-1.41; P = .27), and patient survival (84.0% vs 87.5%; OR, 0.79; 95% CI, 0.40-1.55; P = .49).

CONCLUSIONS

For infrapopliteal arterial occlusive disease, primary stenting has the same 1-year benefits as PTA. There is insufficient evidence to support the superiority of either method. Primary stenting is associated with a trend toward higher primary patency and lower secondary patency. Further large-scale prospective randomized trials should produce more reliable results.

Randomized trials for endovascular treatment of infrainguinal arterial disease: systematic review and meta-analysis (Part 2: Below the knee)

OBJECTIVE

To evaluate 1 to 48 month follow-up outcomes of different endovascular treatment strategies in below-the-knee (BTK) arterial segments in critical limb ischemia (CLI) patients.

METHODS

Medline and Embase were searched (last searched on 5 November 2013) for studies of randomized controlled trials comparing either balloon angioplasty (PTA) or drug-eluting balloon (DEB) with optional bailout stenting, or primary stenting using a bare stent (BS) or drug-eluting stent (DES) to one another. Methodological quality of each trial was assessed using a Cochrane Collaboration's tool, and quality of evidence was assessed using the GRADE system. Outcomes assessed were wound healing, quality of life, change in Rutherford classification, amputation, death, target lesion revascularization (TLR), bypass, binary restenosis, late lumen loss, stenosis grade, and event-free survival with follow-up periods of at least 1 month.

RESULTS

Twelve trials including 1145 patients were identified, with 90% of patients having CLI. Six BS versus PTA and two DES versus PTA trials showed low-quality evidence of equal efficacy. One trial, comparing DEB with PTA, showed moderate-quality evidence of improved wound healing (RR 1.28; 95% CI: 1.05 to 1.56; p=.01), improvement in Rutherford classification (RR 1.32; 95% CI: 1.08 to 1.60; p=.008), and lower TLR (RR 0.41; 95% CI 0.23 to 0.74; p=.002) and binary restenosis (RR 0.36; 95% CI 0.24 to 0.54; p<.0001) in diabetic patients after 12 months. Amputation and death rate did not differ significantly. For DES versus BS, most trials showed equal efficacy between strategies.

CONCLUSION

Based on low- to moderate-quality evidence, PTA with optional bailout stenting using BS should remain the preferred strategy in treating CLI patients with BTK arterial lesions. Before other strategies can be implemented, larger and high-quality RCTs assessing clinically relevant outcomes are needed.

Does patency matter in patients with critical limb ischemia undergoing endovascular revascularization?

Restenosis is the major drawback in patients undergoing tibial angioplasty. In contrast to earlier observations, tibial patency was shown to impact on clinical outcomes in current randomized trials and is thus attributed more importance. Accordingly, intentions to reduce tibial restenosis have been intensified. Both drug-eluting balloons (DEB) and drug-eluting stents (DES) were shown to reduce tibial restenosis when compared with its plain counterparts. However, both endovascular technologies have its limitations for tibial arterial application. While DEB technology may not address elastic recoil, a pathophysiological mechanism frequently observed in tibial arteries and a significant contributor to restenosis, currently available DES do not fully address tibial arterial lesion morphology. Purpose of the present manuscript is to outline the problem and the incidence of tibial arterial restenosis, its importance on clinical outcomes and to provide an overview on technical developments aimed at its prevention.

Systematic review and meta-analysis of additional technologies to enhance angioplasty for infrainguinal peripheral arterial occlusive disease

Background

There are several additional techniques designed to enhance conventional percutaneous transluminal balloon angioplasty (PTA). This systematic review assessed current evidence on the clinical effectiveness of additional techniques for infrainguinal peripheral arterial occlusive disease (PAD).

Methods

Relevant electronic databases, including MEDLINE, were searched in May 2011. The population comprised participants with symptomatic PAD undergoing endovascular treatment for disease distal to the inguinal ligament. Interventions were additional techniques compared with conventional PTA. Main outcome measures were restenosis and need for reintervention. Randomized clinical trials (RCTs) of clinical effectiveness were assessed for quality and data were extracted. Where appropriate, meta-analysis was undertaken to produce risk ratios (RRs).

Results

Forty RCTs were selected. Meta-analysis showed a significant benefit in reducing restenosis rates at 6 months for self-expanding stents (RR 0·49) and drug-coated balloons (RR 0·40), and at 12 months for endovascular brachytherapy (RR 0·63). There was also evidence that use of a stent-graft significantly reduced restenosis compared with PTA, as did drug-eluting stents compared with bare-metal stents. Meta-analysis showed that use of drug-coated balloons was associated with significantly lower reintervention rates than PTA alone at 6 months (RR 0·24) and 24 months (RR 0·27) of follow-up. There was also evidence of significantly lower reintervention rates for self-expanding stents at 6 months. Other techniques did not show significant treatment effects for restenosis or reintervention.

Conclusion

The conclusions of this review should be tempered by small sample sizes, lack of clinical outcome measures and differing outcome definitions, making direct comparison across trials difficult. However, self-expanding stents, drug-eluting stents and drug-coated balloons appeared to be the most promising technologies worthy of future study.

Endovascular techniques in limb salvage: stents

In patients with critical limb ischemia, the first-line approach for limb salvage has shifted over the past decade from bypass surgery to endovascular intervention. Stenting for the treatment of lower-extremity arterial occlusive disease is an important tool and continues to evolve, with new stent designs and technologies that have been developed to provide superior patency rates and limb salvage. In this article, we discuss the role of peripheral stenting in the treatment of patients with critical limb ischemia, including a review of the relevant current literature and the future directions of such interventions.

Endovascular stents: a review of their use in peripheral arterial disease

Technological advances in the past decade have shifted revascularization strategies from traditional open surgical approaches toward lower-morbidity percutaneous endovascular treatments for patients with lower extremity peripheral arterial disease (PAD). The continuing advances in stent design, more than any other advances, have fueled the growth of catheter-based procedures by improving the safety, durability, and predictability of percutaneous revascularization. Although the 2007 TransAtlantic Inter-Society Consensus (TASC) guidelines recommend endovascular therapy for type A and B aortoiliac and femoropopliteal lesions, recent developments in stent technology and increased experience of interventionists have suggested that a strategy of endovascular therapy first is appropriate in experienced hands for TASC type D lesions. The role of endovascular interventions is also expanding in the treatment of limb-threatening ischemia.

Chronic critical limb ischemia

BACKGROUND

Some 40 000 lower limb amputations are performed in Germany each year, 70% of them in diabetics. About 80% of all major amputations may be preventable with the use of new interventional and vascular surgical procedures, particularly on the arteries of the leg and foot. We present the current state of the art in revascularization techniques and evaluate their usefulness for preservation of the lower limb.

METHODS

This overview is based on the guidelines for the diagnosis and treatment of peripheral artery disease (PAD) and diabetic foot syndrome (DFS) that have been issued by the American Heart Association (AHA), the American College of Cardiology (ACC), the German Society of Angiology (DGA), the Trans-Atlantic Intersociety Consensus (TASC II), the German Society of Vascular Surgery (DGG), and the German Diabetes Society (DDG). A selective search in PubMed for relevant articles that appeared from 2000 to 2011 was conducted with the search terms "pedal bypass," "vascular intervention crural pedal," and "crural-pedal revascularization."

RESULTS

Most of the data on crural and pedal revascularization are derived from small-scale studies. The few comparative studies of interventional treatments and bypass surgery have not revealed any significant differences in outcome, but all studies of revascularization have shown good success rates for lower limb preservation.

CONCLUSION

Though the data are still sparse, the high reported rates of limb preservation imply that peripheral revascularization techniques can play a major role in the treatment of chronic critical limb ischemia (CLI). Therefore, these techniques are recommended without exception by the current guidelines.

Randomized comparison of everolimus-eluting versus bare-metal stents in patients with critical limb ischemia and infrapopliteal arterial occlusive disease

OBJECTIVE

Critical limb ischemia, the most severe form of peripheral arterial disease, results in extremity amputation if left untreated. Endovascular recanalization of stenotic or occluded infrapopliteal arteries has recently emerged as an effective form of therapy, although the duration of patency is typically limited by restenosis. Recently, it has been suggested that drug-eluting stents originally developed for the coronary arteries might also be effective in preventing restenosis in the infrapopliteal arteries. This prospective, randomized, controlled clinical trial tested the hypothesis that treatment of infrapopliteal arterial occlusive lesions with an everolimus-eluting stent (Xience V) would provide superior patency to treatment with a bare-metal stent (Multi-Link Vision).

METHODS

A sample size of 140 patients was planned to be enrolled at five European investigative sites. The primary end point was arterial patency at 12 months, defined as the absence of ≥50% restenosis based on quantitative analysis of contrast angiography.

RESULTS

Between March of 2008 and September of 2009, 74 patients were treated with Xience V and 66 patients were treated with Vision. After 12 months, the primary patency rate after treatment with Xience V was 85% compared with 54% after treatment with Vision (P = .0001). Treatment with Xience V significantly reduced mean in-stent diameter stenosis (21% ± 21% vs 47% ± 27%; P < .0001) and mean in-stent late lumen loss (0.78 ± 0.63 vs 1.41 ± 0.89 mm; P = .001). There were no differences in the percentage of patients receiving a designation of Rutherford class 0 or 1 at the 12-month follow-up visit (56% for Vision, vs 60% for Xience V; P = .68). Major extremity amputations were rare in both groups (two for Vision and one for Xience V). The use of the Xience V stent significantly reduced the need for repeat intervention: freedom from target lesion revascularization was 91% for Xience V vs 66% for Vision (P = .001).

CONCLUSIONS

Treatment of the infrapopliteal occlusive lesions of critical limb ischemia with everolimus-eluting stents reduces restenosis and the need for reintervention compared with bare metal stents.

Tibial intervention for critical limb ischemia

Diagnosis and treatment of critical limb ischemia (CLI) is increasingly important as the average age of the world population and the incidence of diabetes and metabolic syndrome increases. Fortunately, most patients will not progress to this stage of peripheral arterial disease, yet if left untreated, there is a high risk of future cardiovascular events. At the point of ischemic rest pain or tissue loss, there are significant implications for morbidity and mortality. There is a high prevalence of multisegment occlusive disease in the CLI patient with the infrapopliteal vessels frequently involved. Revascularization of the affected limb is of utmost importance as the prospects of wound healing and relief of ischemic rest pain are poor without reestablishing continuous flow to the distal extremity. With the advent of endovascular devices designed to treat this vexing problem, the ability to successfully treat this difficult patient population with less procedural morbidity has been greatly enhanced.

Peripheral artery disease. Part 2: medical and endovascular treatment

The treatment of peripheral artery disease (PAD) focuses on risk factor modification, cardiovascular event reduction, limb viability, and symptom improvement. Hypertension, hyperlipidemia, and diabetes mellitus should all be controlled to recommended target levels, and smoking cessation is vital. Antiplatelet therapies, such as aspirin or clopidogrel, should be administered in all patients unless contraindicated. Whenever possible, patients who present with claudication should be offered a regimen comprised of both medical and exercise therapy, which often results in substantial improvement in symptoms. For patients presenting with more-advanced disease, such as acute limb ischemia, critical limb ischemia, and severely-limiting symptoms of PAD, revascularization is often necessary. As a result of the rapid evolution in endovascular revascularization technology and expertise, many patients with PAD can be treated percutaneously. Therefore, in this Review, we will focus on medical therapy and endovascular revascularization of patients with PAD, with reference to surgical bypass in specific clinical scenarios.

Sirolimus-eluting stents vs. bare-metal stents for treatment of focal lesions in infrapopliteal arteries: a double-blind, multi-centre, randomized clinical trial

AIMS

Preliminary reports indicate that sirolimus-eluting stents reduce the risk of restenosis after percutaneous infrapopliteal artery revascularization. We conducted a prospective, randomized, multi-centre, double-blind trial comparing a polymer-free sirolimus-eluting stent with a placebo-coated bare-metal stent in patients with either intermittent claudication or critical limb ischaemia who had a de-novo lesion in an infrapopliteal artery.

METHODS AND RESULTS

161 patients were included in this trial. The mean target lesion length was 31 ± 9 mm. The main study endpoint was the 1-year primary patency rate, defined as freedom from in-stent-restenosis (luminal narrowing of ≥50%) detected with duplex ultrasound if not appropriate with angiography. Secondary endpoints included the 6-month primary patency rate, secondary patency rate, and changes in Rutherford-Becker classification after 1 year. Twenty-five (15.5%) patients died during the follow-up period. One hundred and twenty-five patients reached the 1-year examinations. The 1-year primary patency rate was significantly higher in the sirolimus-eluting stent group (80.6%) than in the bare-metal stent group (55.6%, P= 0.004), and the 1-year secondary patency rates were 91.9 and 71.4% (P= 0.005), respectively. The median (interquartile range) change in Rutherford-Becker classification after 1 year was -2 (-3 to -1) in the sirolimus-eluting stent group and -1 (-2 to 0) in the bare-metal stent group, respectively (P= 0.004).

CONCLUSION

Mid-term patency rates of focal infrapopliteal lesions are substantially improved with sirolimus-eluting stent compared with bare-metal stent. Corresponding to the technical results, the changes in Rutherford-Becker classification reveal a significant advantage for the sirolimus-eluting stent.