Below knee bare nitinol stent placement in high-risk patients with critical limb ischemia is still durable after 24 months of follow-up

Drug Eluting Stents Below the Knee: Patency, Amputation-Rate, and Mortality-A Systematic Review of the Literature

BACKGROUND

Numerous meta-analyses and multicenter randomized controlled trials have demonstrated that drug-eluting stents (DES) offer superior outcomes in terms of primary patency and limb salvage compared to other endovascular modalities such as balloon angioplasty and bare metal stents. This review aims to systematically analyze the literature on the clinical outcomes of DES for the treatment of infrapopliteal arterial occlusions.

METHODS

This study is a systematic review. Comprehensive searches were conducted in the MEDLINE, EMBASE, Ovid, Cochrane, DAR, and BVS databases. Eligible studies were those that reported outcomes of DES in the treatment of infrapopliteal arterial disease, with no restrictions on time frame, publication status, or language. The primary outcome assessed was the primary patency of the stent, while secondary outcomes included the rates of re-occlusion and mortality.

RESULTS

A total of 27 studies involving 2470 patients were included in the analysis, in which 1191 patients come from prospective multicenter studies. The mean age of the participants was 73.4 years. Approximately, 50% of the patients had diabetes mellitus and/or chronic renal failure, and 33.3% had heart disease. The fibular artery was the most frequently affected by stenosis, involved in 50.2% of cases, followed by the anterior tibial artery in 34.6% of cases and the posterior tibial artery in 15.2% of cases. The average patency rate following DES treatment was 72.2% at 12 months. The rate of re-occlusion was 21.6%, and the mortality rate was 16.6%. However, due to the heterogeneity of the sample and incomplete data, it was not possible to draw definitive correlations between patency, amputation rates, and mortality.

CONCLUSION

This systematic review and analysis revealed significant limitations due to the heterogeneity of the sample and incomplete data, preventing a comprehensive stratification of the findings. As a result, we are not yet able to fully address the research questions posed. Further studies with extended follow-up periods are needed to standardize the treatment of infrapopliteal arterial occlusions and provide more definitive conclusions.Clinical ImpactThis review assessed the efficacy and safety of drug-eluting stents for below-the-knee lesions, showing promising patency and safety results. Their use in daily practice may aid in treating lesions prone to recoil and dissection after angioplasty. Despite some data inconsistencies, the findings remain encouraging. Drug-eluting stents demonstrated better outcomes than Bare-metal Stent, supporting their consideration in clinical practice for below-the-knee vascular treatment.

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).

The role of atherectomy in BTK lesions. A systematic review

INTRODUCTION

To evaluate the current role of atherectomy techniques (ATH) in treatment of peripheral arterial disease (PAD) at below the knee (BTK) arteries.

EVIDENCE ACQUISITION

The PubMed and Embase were searched (last search on 11 September 2021) for studies reporting on the early and mid-term outcomes of ATH in BTK vessels. Analysis included the data from six studies, with a total of 1062 PAD patients treated with various ATH techniques. We compared them the ATH outcomes with the contemporaneous outcomes of plain balloon angioplasty alone or with bailout stenting. Early safety and efficacy were accessed with perioperative and 30-day technical success rate, which included the primary patency of the treated BTK arterial segment. Evaluation of clinical performance was based on target limb revascularization (TLR) and on major limb adverse events (MALEs) rates.

EVIDENCE SYNTHESIS

The current body of literature mainly includes retrospective observational studies, and the level of derived evidence is low. The mean perioperative and 30-day technical success rate was 87.3%. The mean reported TLR and MALEs rates at 12 months were 6.6% and 4.7% respectively. The relevant rates in studies reporting at 24 months were 24.3% and 31.7% while in studies reporting at 36 months the rates were 37.0% and 23.0% respectively.

CONCLUSIONS

Based in low-quality evidence, it seems that ATH in BTK vessels has a high safety, high efficacy profile and durable outcomes at 12 months. In the midterm, the clinical success of ATH is compromised by increased TLR and MALEs rates. Comparison of ATH with other endovascular techniques in BTK treatment of PAD shows a slight lead of ATH at 1-year and equivalent clinical performance in the mid-term. Overall, ATH has a significant and potentially predominant role in treatment of BTK vessels.

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

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

Antegrade vs Crossover Femoral Artery Access in the Endovascular Treatment of Isolated Below-the-Knee Lesions in Patients With Critical Limb Ischemia

Purpose: To evaluate the safety and effectiveness of antegrade vs crossover femoral artery access in the endovascular treatment of isolated below-the-knee (BTK) lesions in patients with critical limb ischemia (CLI). Methods: Between January 2014 and December 2015, 224 high-risk patients (mean age 75.8±9.8 years; 151 men) with CLI underwent infragenicular interventions on 292 crural vessels in 3 European vascular centers. All patients had isolated TransAtlantic Inter-Society Consensus (TASC) C (n=26) or D (n=198) BTK lesions. Primary endpoints were freedom from access-related complications and technical success comparing the antegrade vs crossover access groups. Results: Balloon angioplasty was the most used treatment modality (169 vessels, 75.4%). The technical success rate was 88.4% in the entire cohort and 88.0% in the antegrade group vs 90.4% in the crossover group (p>0.99). In all patients, the technical success rate was higher for stenotic lesions (100%) vs occlusions (85.5%, p=0.002) and in patients with TASC C BTK lesions (100%) vs TASC D (86.9%, p=0.033). The overall freedom from access-related complications was 97.8%: 99% in the antegrade group and 90.6% in the crossover group (p=0.022). Larger sheath size (5/6-F vs 4-F) was associated with a significantly higher risk for access-related complications (7.1% vs 1.1%, respectively; p=0.047). Conclusion: The present multicenter study showed high technical success and a low incidence of access-related complications in the treatment of isolated BTK lesions using either antegrade or crossover femoral access. The antegrade approach with the use of a 4-F system seems to have a significantly lower rate of access-related complications.

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.

Bypass vs. Endovascular Therapy of Infrapopliteal Lesions for Critical Limb Ischemia

OBJECTIVE

This study was conducted to determine whether to perform endovascular intervention or bypass surgery as a treatment option for critical limb ischemia (CLI) with lesions in the popliteal artery or below.

SUBJECTS AND METHODS

A total of 150 patients (164 limbs) with CLI underwent endovascular intervention or bypass surgery for lesions in the popliteal artery or below at our department between May 1995 and June 2011. Therapeutic outcomes were examined by surgical technique. An indication for endovascular intervention was established with the combination of (1) poor general condition, and (2) a stenotic or occlusive lesion ≤5 cm.

RESULTS

The bypass group (group B) comprised 119 patients (99 males, 20 females) with 131 affected limbs at 46 to 89 years of age (mean: 70 years). The endovascular intervention group (group E) comprised 31 patients (25 males, 6 females) with 33 affected limbs at 47 to 89 years of age (mean: 72 years). There was no significant difference in patient demography between the two groups. Regarding preoperative complications, hypertension was observed in 54% and 61% of the subjects in groups B and E, respectively, diabetes in 36% and 55%, renal dysfunction in 29% and 58%, ischemic heart disease in 27% and 32%, and cerebrovascular disorder in 18% and 23%; renal dysfunction accounted for a significantly higher percentage in group E. As for early postoperative complications, subjects in group B experienced wound infections (6 patients), hemorrhage (2), thrombosis (2), pneumonia (1), and another complication (1), and those in group E experienced wound infections (1) and another complication (1). The hospital mortality rate was 0.8% (1 patient) for group B and 0% for group E. The 3-year cumulative primary patency rate was 72% for group B and 54% for group E; the rate was significantly higher for group B. The 3-year secondary patency rate was 82% for group B and 60% for group E. The 3-year limb salvage rate was 86% for group B and 82% for group E; there was no significant difference between the two groups. The 5-year survival rate was 57% for group B and 42% for group E; the survival rate was significantly lower for group E.

CONCLUSION

For the study population of CLI patients with lesions in the popliteal artery or below, the patency rate was higher for the bypass group than for the endovascular intervention group, whereas there was no difference in the limb salvage rate. Based on the findings in prognosis for survival, the indication for endovascular intervention at our department is believed to be appropriate. (English translation of Jpn J Vasc Surg 2013; 22: 715-718).

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.

Meta-analysis of outcomes of endovascular treatment of infrapopliteal occlusive disease with drug-eluting stents

PURPOSE

To review emerging evidence regarding the use of bare metal (BMS) vs. drug-eluting stents (DES) in the treatment of infrapopliteal occlusive disease.

METHODS

A systematic review of the literature was undertaken to identify all studies comparing stent treatments of infragenicular vessels in patients with chronic lower limb ischemia. Validated methods to assess the methodological quality of the included studies were applied. Outcome data were pooled, and combined overall effect sizes were calculated using fixed or random effects models. The search identified 4 randomized clinical trials and 2 observational studies reporting on 544 patients (287 treated with DES and 257 treated with BMS). Data are presented as the odds ratio (OR) with 95% confidence interval (CI) and the number-needed-to-treat (NNT).

RESULTS

Primary patency, freedom from target lesion revascularization, and clinical improvement at 1 year were significantly higher in the DES recipients compared to patients treated with BMS (OR 4.511, 95% CI 2.897 to 7.024, p<0.001, NNT 3.5; OR 3.238, 95% CI 2.019 to 5.192, p<0.001, NNT 6.0; and OR 1.792, 95% CI 1.039 to 3.090, p=0.036, NNT 7.3, respectively). No significant differences in limb salvage and overall survival at 1 year were identified between the groups (OR 2.008, 95% CI 0.722 to 5.585, p=0.181; OR 1.262, 95% CI 0.605 to 2.634, p=0.535, respectively). Sensitivity analyses investigating the potential effects of study design and type of DES on the combined outcome estimates validated the results.

CONCLUSION

Our analysis has demonstrated superior short-term results with DES compared with BMS, expressed by increased patency and freedom from target lesion revascularization. The influence of this finding on clinical surrogate endpoints, such as limb salvage, remains unknown.

Interventional radiology in the diabetic lower extremity

Most of what we know today for interventional techniques for revascularization in patients with DF disease is derived from our knowledge on CLI in patients with PAD. There are today no dedicated randomized controlled trials on interventional treatment of DF. It is, however, clear that huge progress in interventional techniques has been obtained during the past decade. In most institutions, the nonsurgical option is the current first choice. As the aim of treatment is ulcer healing through temporary increase in blood flow, it is still unclear what the contribution of new stent and drug-eluting technologies will have on the clinical outcome of DF treatment. Long-term follow-up studies, dedicated to patients with an arterial DF problem, have to be performed before we can evaluate all these new technologies.

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

INTRODUCTION

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

What would surgeons like from materials scientists?

Surgery involves the repair, resection, replacement, or improvement of body parts and functions and in numerous ways, surgery should be considered human engineering. There are many areas in which surgical materials could be improved, but surgeons are generally unaware of materials available for use, while materials scientists do not know what surgeons require. This article will review some of the areas where surgeons and materials scientists have interacted in the past and will discuss some of the most pressing problems which remain to be solved. These include better implant materials for hernia repair, breast reconstruction, the treatment of diabetes, vascular stenting and reconstruction, and electrical pacing devices. The combination of tissue engineering and nanomaterials has great potential for application to nearly every aspect of surgery. Tissue engineering will allow cells or artificial organs to be grown for specific uses while nanotechnology will help to ensure maximal biocompatibility. Biosensors will be combined with improved electrodes and pacing devices to control impaired neurological functions.

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

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

Retrograde approach for endovascular salvage of an infrapopliteal vein bypass

Endovascular treatment through femoropopliteal and infragenicular percutaneous transluminal angioplasty, both in native vessels and in bypass salvage, has been an emerging technique in recent years. However, in some cases, a difficult anterograde access in distal occlusions has limited the technical success of this procedure. Combined subintimal arterial flossing with antegrade-retrograde intervention is used as a resource technique to obtain precise recanalization in these cases. Here, we present the case of a retromalleolar access of the posterior tibial artery, based on subintimal arterial flossing with antegrade-retrograde intervention technique, to achieve femoral-posterior tibial bypass salvage.