Endovascular Treatment of Popliteal Artery Segments P1 and P2 in Patients With Critical Limb Ischemia: Initial Experience Using a Helical Nitinol Stent With Increased Radial Force

Clinical Outcomes After Drug-Coated Balloon Treatment in Popliteal Artery Disease: K-POP Registry 12-Month Results

BACKGROUND AND OBJECTIVES

The popliteal artery is generally regarded as a "no-stent zone". Limited data are available on the outcomes of drug-coated balloons (DCBs) for popliteal artery disease. This study aimed to evaluate the 12-month clinical outcomes among patients who received DCB treatment for atherosclerotic popliteal artery disease.

METHODS

This prospective, multicenter registry study enrolled 100 patients from 7 Korean endovascular centers who underwent endovascular therapy using IN.PACT DCB (Medtronic) for symptomatic atherosclerotic popliteal artery disease. The primary endpoint was 12-month clinical primary patency and the secondary endpoint was clinically driven target lesion revascularization (TLR)-free rate.

RESULTS

The mean age of the study cohort was 65.7±10.8 years, and 77% of enrolled patients were men. The mean lesion length was 93.7±53.7 mm, and total occlusions were present in 45% of patients. Technical success was achieved in all patients. Combined atherectomy was performed in 17% and provisional stenting was required in 11%. Out of the enrolled patients, 91 patients completed the 12-month follow-up. Clinical primary patency and TLR-free survival rates at 12 months were 76.0% and 87.2%, respectively. A multivariate Cox regression analysis identified female and longer lesion length as the significant independent predictors of loss of patency.

CONCLUSIONS

DCB treatment yielded favorable 12-month clinical primary patency and TLR-free survival outcomes in patients with popliteal artery disease.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02698345.

Outcomes of endovascular intervention for atherosclerotic lesions confined to the popliteal artery

OBJECTIVE

Most surgeons employ an endovascular-first approach to the treatment of peripheral arterial disease (PAD), but controversy remains regarding the ideal interventions for the management of isolated popliteal artery disease (IPAD). Indeed, there are a paucity of data that compare outcomes of popliteal stents vs other peripheral vascular interventions (PVIs). The goal of this study was to evaluate outcomes of PVIs in IPAD.

METHODS

The Vascular Study Group of New England database was queried for all IPAD PVIs performed for atherosclerotic occlusive disease from 2010 to 2021. Those with at least 1 year of follow-up data available were included for analysis. The primary endpoint was 1-year freedom from a composite target lesion (TL) treatment failure that included restenosis >50% on duplex, reintervention, or ipsilateral major amputation.

RESULTS

We included 689 procedures performed on 634 patients. Of these, 250 (36.3%) were treated with plain balloons (POBA), 215 (31.2%) had stents, 170 (24.7%) had special balloons (drug-coated, cutting, or lithotripsy), and 54 (7.8%) atherectomies were performed. Stent placement was associated with lower freedom from TL treatment failure (72.6%) than special balloon (81.2%; P = .048) and atherectomy (88.9%; P = .012), but not POBA (76.8%; P = .293). On multivariable logistic regression, stents (odds ratio, 0.637; P = .021) and preoperative P2Y12 inhibitor therapy (odds ratio, 0.683; P = .048) were both associated with lower freedom from intervention failure.

CONCLUSIONS

Popliteal stent placement is associated with a higher rate of TL treatment failure at 1 year when compared with other PVIs including special balloon angioplasty and atherectomy, but not POBA, and should therefore be avoided in favor of special balloons or atherectomy whenever feasible.

Biomimetic Stents for Infrainguinal Peripheral Arterial Disease: Systematic Review and Meta-Analysis

OBJECTIVE

Biomimetic stents are peripheral infrainguinal self expanding stents that mimic the anatomy of the vasculature and artery movement. They are indicated for use in infrainguinal arteries. This research aimed to synthesise all current evidence on the use of biomimetic stents as adjuncts for endovascular treatment of infrainguinal peripheral arterial disease (PAD), helping to guide clinical decision making.

DATA SOURCES

MEDLINE, Embase, CINAHL and Cochrane databases.

REVIEW METHODS

Random effects meta-analysis following PRISMA guidelines (PROSPERO registration CRD42022385256). Study quality was assessed using the Joanna Briggs Institute critical appraisal tools checklist, and certainty assessment through the Grading of Recommendations, Assessment, Development and Evaluation (GRADE). Endpoints included primary patency, target lesion revascularisation, stent fracture, secondary patency, and Death at one year.

RESULTS

In total, 37 studies were included in the meta-analysis (33 cohort studies, two case series, and two randomised controlled trials [RCTs]), representing 4 480 participants. Of these, 34 studies included data on the Supera (81.5% of participants) and three studies reported data on the BioMimics 3D (18.5% of participants) stents. The pooled primary patency rate of 33 studies at one year follow up was 81.4% (95% confidence interval [CI] 78.7 - 83.9%), and the pooled target lesion revascularisation rate of 18 studies at one year was 12.2% (95% CI 9.6 - 15.0%). The certainty of evidence outcome rating as qualified by GRADE was very low for both. Only one study reported a positive stent fracture rate at one year follow up of 0.4% with a certainty of evidence outcome of low.

CONCLUSION

Using biomimetic stents for infrainguinal PAD may be associated with acceptable one year primary patency and target lesion revascularisation rates, with a near negligible one year stent fracture rate. Their use should be considered in those presenting with infrainguinal PAD undergoing endovascular revascularisation. A RCT is necessary to determine their clinical and cost effectiveness.

Deformed Popliteal Artery Due to Highly Flexed Knee Position Can Cause Kinks, Creating an Unfavorable Hemodynamic State

BACKGROUND

Endovascular treatment devices of the femoropopliteal artery have evolved, improving clinical results. However, the effects of dynamic changes in the popliteal artery during knee flexion have not been sufficiently investigated. In this study we performed a 3-dimensional analysis to clarify the dynamic changes in the popliteal artery during knee flexion and their effects on hemodynamics.Methods and Results: To analyze dynamic changes in the popliteal artery in the knee flexion position, a computed tomography protocol was developed in the right-angled and maximum flexion knee positions. Thirty patients with lower extremity artery disease were recruited. V-Modeler software was used for anatomical and hemodynamic analyses. Various types of deformations of the popliteal artery were revealed, including hinge points and accessory flexions. Kinks can occur in the maximum flexion position; however, they rarely occur in the right-angled flexion position. In addition, hemodynamic analysis revealed a tendency for lower minimum wall shear stress and a higher maximum oscillatory shear index at the maximum curvature of the popliteal artery.

CONCLUSIONS

Kinks in the maximum flexion position suggested that the outcome of endovascular treatment may change in areas such as Japan, where knee flexion is customary. Hemodynamics at the maximum curvature of the popliteal artery indicated that the luminal condition was unfavorable for endovascular treatment.

Self-expanding interwoven nitinol stent in severe femoropopliteal arterial disease. Real life results of the Supera Peripheral Stent System®

PURPOSE

The excellent performance of the Supera Peripheral Stent System® by Abbott Vascular in femoropopliteal interventions has already been proven through several trials. This retrospective study aims to evaluate the durability and long-term patency of the Supera stent for the treatment of severe femoropopliteal lesions in a real-world population.

METHODS

A retrospective analysis was conducted of 136 consecutive limbs from 128 patients with atherosclerotic disease in the femoropopliteal region, treated with Supera stents between September 2010 and September 2017. As primary endpoints patency rates and freedom from target lesion revascularization (TLR) were calculated and presented using Kaplan-Meier analysis.

RESULTS

Fifty-five percent were treated for claudication (IC), 45% for chronical limb threatening ischemia (CLTI). The mean treated lesion length was 143 mm (±77.8). The majority of lesions (63%) were Trans-Atlantic Inter-Society Consensus Criteria II (TASC II) C/D lesions. The overall primary patency rates at 12 and 24 months of follow-up were 72.6% and 60.8% respectively. The primary patency at 12 and 24 months for TASC II A/B lesions was respectively 86% and 75.4%. For TASC II C/D lesions primary patency at 12 and 24 months was 64% and 51.1% respectively (p = 0.001). Overall freedom from TLR after 12 and 24 months was 73.8% and 62.8% respectively. No significant patency differences were observed based on calcification rate.

CONCLUSION

Endovascular treatment of femoropopliteal disease with Supera Stent is safe, even in extensive, highly calcified lesions. Patency rates and freedom from TLR are acceptable in a real-life population.

Three-Year Real-World Outcomes of Interwoven Nitinol Supera Stent Implantation in Long and Complex Femoropopliteal Lesions

BACKGROUND

Peripheral artery disease (PAD) remains a major issue in modern societies and affects more than 200 million people around the world. Endovascular methods have been evaluated to be safe and effective in limb salvage. The Supera is able to withstand increased compression, biomechanical stress and to have higher radial force. The objective of this study is to evaluate performance, durability and 3-year patency of Supera stent implantation in severe femoropopliteal disease.

METHODS

A retrospective real-world analysis was performed with consideration of 77 patients that had a Supera stent implanted with femoropopliteal atherosclerotic disease at a single center. Among the 77 individuals, 92 Supera stents were implanted. Analysis of patients' demographics, lesions characteristics, reintervention rates and patency rates was performed.

RESULTS

The median follow-up was 33 months and ranged from 0 to 84 months. Chronic limb-threatening ischemia was observed among 43 patients. Mean lesion length was 152.8 ± 94.6 mm. Chronic total occlusions were observed in a majority of lesions. Overall, primary patency rates at 6, 12, 24 and 36 months were 85.0%, 73.6%, 59.2% and 53.2%, respectively.

CONCLUSIONS

The Supera stent is effective in the management of long and complex lesions. The results of patency rates were evaluated to be worse among lesions extending to the popliteal artery.

What should we expect from intravascular ultrasound use for complex femoropopliteal lesions?

In this review article, we summarize the clinical benefit of intravascular ultrasounds (IVUS) in the endovascular therapy (EVT) of complex femoropopliteal (FP) lesions. Due to the development of novel FP-dedicated devices, outcomes of FP-EVT have been improved. As a result, revascularization methods for the FP lesions have shifted to EVT. However, the long-term durability in complex FP lesions has not yet reached that of bypass surgery using autogenous vein. Strategies for EVT of complex FP lesions are still inconsistent and have room for improvement. Long-term results generally depend on the patient and lesion backgrounds but are also affected by the quality of the procedure. Previous reports have shown IVUS evaluation can better assess vessel size compared to conventional angiographic evaluation. In contrast to angio-guided EVT, which evaluates vessel size by inner diameter, IVUS can be evaluated it with an external elastic membrane, which leads to the selection of a more appropriate (basically, larger) size device. Conversely, angiographic evaluation underestimates the vessel size, suggesting that it may lead to insufficient result. Furthermore, IVUS can also assess the adequate guidewire route, presence of severe dissection etc. As the evidence so far shows, the use of IVUS may improve the quality of EVT procedure, resulting in improved long-term outcomes. In conclusion, despite the widespread use of IVUS in FP-EVT practice, it still conditionally applied. The purpose of IVUS in the EVT of complex FP lesions should be clarified. More evidence regarding the IVUS in complex FP lesions is needed.

Supera stent implantation for the treatment of isolated popliteal artery disease systematic review and evaluation of current endovascular strategies

<b>Introduction:</b> The anatomical location of the popliteal artery is one of the greatest challenges for percutaneous interventions. The biomechanical attributes of the vessel lead to higher rates of restenosis, stent fracture, and occlusion. Some surgeons consider the popliteal artery as a no stenting zone. Many specialists favor percutaneous transluminal angioplasty to be the first line of endovascular treatment in the popliteal artery with bail-out stent implantation if the results are suboptimal. The Supera peripheral stent system is a novel stent that has been manufactured with a high degree of flexibility and supposedly might be appropriate for implantation in the popliteal artery. </br></br> <b>Aim:</b> Evaluation of the performance of Supera stent in isolated popliteal artery disease in comparison to other methods of treatment. </br></br> <b>Methods:</b> As many as 92 articles were found in the databases and after full-text review, 4 studies matched the inclusion criteria and were evaluated. </br></br> <b>Results:</b> Primary patency rates of Supera implantation in an isolated popliteal artery at 12 months ranged from 68% to 90%. In all four studies, no stent fractures were observed. Only one study provided longer follow-up than 12 months and evaluated the performance of the Supera stent 36 months after implantation. </br></br> <b>Conclusion:</b> In conclusion, mentioned studies show promising and superior to other stent patency rates of the Supera stent regarding popliteal artery lesions. What is more, no stent fracture is promising regarding longer follow-up. However, more studies with longer follow-ups and direct comparison to other methods are required to fully evaluate Supera's performance in the popliteal artery.

A systematic review and meta-analysis of Supera interwoven nitinol stents for the treatment of infrainguinal peripheral arterial disease

INTRODUCTION

Stenting of infrainguinal lesions can be rather challenging due to the mechanical stress applied on the arteries during motion. We assessed the short-term and mid-term safety and efficacy of Supera interwoven nitinol stent for the treatment of infrainguinal arterial disease.

EVIDENCE ACQUISITION

We conducted a systematic review for articles published from December 2011 up to May 2021 regarding studies assessing the safety and efficacy of Supera interwoven nitinol stents for the treatment of infra-inguinal peripheral arterial disease. Studies that involved synchronous application of the Supera stent and drug delivering devices, or any alternative endoprosthesis were excluded. Pooled Kaplan-Meier survival curves and smoothed hazard estimates were generated. Data were meta-analyzed using a random effects model. Primary endpoints included primary patency and freedom from clinically driven target lesion revascularization (TRL). Secondary endpoints included technical success and major amputation at 1 year post intervention.

EVIDENCE SYNTHESIS

Seventeen studies with 2015 patients (65.3% males) and a mean lesion length of 137.2 mm were included. Of the total treated lesions, 44.9% involved femoropopliteal artery and 37.4% the popliteal artery. Chronic total occlusions made up 49% of the treated lesions. There were no stent fractures reported. The pooled technical success rate is 99.84% (95% CI: 99.26-100). Pooled major amputation rate at 1 year is 1.48% (95% CI: 0.47-2.87). Pooled primary patency and freedom from TLR rates at 1 year are 83.5% (95% CI: 80.24-86.54) and 90.32% (95% CI: 88.75-91.79), respectively. Pooling of individual patient data produced primary patency and freedom from TLR rates of 84.48% (95% CI: 82.66-86.11) and 90.81% (95% CI: 88.64-92.58) respectively. According to the smoothed hazard ratio estimate the risk for losing primary patency peaked between 4 and 5 months while the risk for TLR peaked between 7 and 8 months after the intervention.

CONCLUSIONS

This review and meta-analysis indicated the safety and efficacy of Supera stents for the treatment of challenging infrainguinal lesions in the short-term and mid-term periods, with acceptable primary patency and freedom from TLR rates. Clinicians should be aware that between 4 and 5 months patients face a higher risk for event occurrence.

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.

Mid-term results and predictors of restenosis in patients undergoing endovascular therapy for isolated popliteal artery steno-occlusive disease

Background and aim

There is only a limited number of major publications on the outcome of interventions for isolated popliteal artery stenosis. The purpose of this study was to report our results on mid-term patency and predictors of restenosis.

Patients and methods

This single-center retrospective study included 61 symptomatic patients (males, N = 33; median age, 65.1 years [IQR, 60.7–71.9 years]; Rutherford grade 4–6, N = 14) with at least two patent crural arteries, whose atherosclerotic stenoses/occlusions were treated with percutaneous transluminal angioplasty (PTA) or stenting (using self-expanding bare-metal Astron Pulsar stents) between 2011 and 2018.

Results

Twenty-six patients had PTA, while 35 underwent stenting. The median follow-up was 29 months (IQR, 10–47 months). The primary patency rates were not significantly different (P = 0.629) between PTA and stenting groups. Restenosis developed in nine patients (34.6%) in the PTA group, and in 12 (34.3%) in the stenting group. Restenotic lesions required re-intervention in nine cases (100%) in the PTA group, and in eight (66.7%) in the stenting group. Restenosis developed significantly less frequently (P = 0.010) in patients with a popliteal/P1 stent; the primary patency rates were also significantly better (P = 0.018) in patients with a popliteal/P1 stent when compared to popliteal/P2 plus multi-segment stents. Cox regression analysis identified lesion location as a predictor of in-stent restenosis (HR, 2.5; 95% CI, 1.2–5.5; P = 0.019).

Conclusion

Stenting was not superior when compared to PTA (if selective stenting was not considered as loss of patency). Follow-up should be more thorough in patients undergoing popliteal/P2 or multi-segment stenting.

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.

Popliteal Artery Angioplasty for Chronic Total Occlusions with versus without the Distal Landing Zone

BACKGROUND

The purpose of this study was to evaluate the outcome of percutaneous transluminal angioplasty in patients with critical limb ischemia due to popliteal artery (PA) chronic total occlusions depending on the presence of a patent portion of the PA distal to the occlusive lesion-the distal landing zone (DLZ).

MATERIALS AND METHODS

We retrospectively analyzed 80 patients with critical limb ischemia (all Rutherford class 5-6), who underwent percutaneous transluminal angioplasty with or without stenting for PA chronic total occlusions with no inflow disease. Baseline demographic and clinical variables, periprocedural outcome, 12-month overall survival, limb salvage, primary patency, freedom from target lesion revascularization (TLR), amputation-free survival, and freedom from major adverse limb events in DLZ versus no-DLZ lesions were assessed.

RESULTS

Of all patients (43 men; mean age 70.2 y), 40 (50%) had DLZ in the PA, whereas another 40 (50%) did not (no-DLZ). Diabetes was significantly more common among DLZ patients and was found to be a risk factor for DLZ compared with no-DLZ lesions (HR 2.58; 95% CI 1.03-6.46; P = 0.04). Other demographic and clinical variables were similar between the groups. The stenting rate was 45.0% versus 42.5% in DLZ versus no-DLZ (P = 1.0). At 12 months, there was no significant difference in primary patency (64.7% vs. 51.6%; P = 0.156), overall survival (73.4% vs. 84.0%; P = 0.283), amputation-free survival (60.0% vs. 68.8%; P = 0.432), and limb salvage rate (93.6% vs. 82.2%; P = 0.126) between DLZ and no-DLZ groups, respectively. However, freedom from TLR (92.1% vs. 67.7%; P = 0.03) and major adverse limb events (80.1% vs. 41.8%; P = 0.003) was significantly higher in DLZ compared with no-DLZ lesions (92.1% vs. 67.7%; P = 0.03).

CONCLUSIONS

Diabetes was found to be a significant risk factor for DLZ compared to no-DLZ lesions. Technical success and stenting rates were similar in DLZ versus no-DLZ patients. At 12 months, there was no significant difference in limb salvage, primary patency, and overall survival between the study groups. The DLZ lesions were associated with a significantly higher freedom from TLR than no-DLZ lesions.

Braided composite stent for peripheral vascular applications

Braided composite stent (BCS), woven with nitinol wires and polyethylene terephthalate (PET) strips, provides a hybrid design of stent. The mechanical performance of this novel stent has not been fully investigated yet. In this work, the influence of five main design factors (number of nitinol wires, braiding angle, diameter of nitinol wire, thickness and stiffness of the PET strip) on the surface coverage, radial strength, and flexibility of the BCS were systematically studied using computational models. The orthogonal experimental design was adopted to quantitatively analyze the sensitivity of multiple factors using the minimal number of study cases. Results have shown that the nitinol wire diameter and the braiding angle are two most important factors determining the mechanical performance of the BCS. A larger nitinol wire diameter led to a larger radial strength and less flexibility of the BCS. A larger braiding angle could provide a larger radial strength and better flexibility. In addition, the impact of the braiding angle decreased when the stent underwent a large deformation. At the same time, the impact of the PET strips increased due to the interaction with nitinol wires. Moreover, the number of PET strips played an important role in the surface coverage. This study could help understand the mechanical performance of BCS stent and provides guidance on the optimal design of the stent targeting less complications.

Newly approved devices for endovascular treatment of femoropopliteal disease: a review of clinical evidence

Introduction: Femoropopliteal lesions account for a significant proportion of endovascular interventions for peripheral artery disease. In this manuscript, we review the literature on the application of newly approved devices in the treatment of atherosclerotic lesions at this segment.Areas covered: New drug-coating technologies provide sustained drug-eluting over time and better scaffolds are more resistant to the increased biomechanical stress at the femoropopliteal segment. Thus, the newer drug-eluting stents (i.e. Eluvia®), nitinol interwoven stents (i.e. Supera®), and drug-coated balloons (i.e. Stellarex®) are associated with improved pharmacokinetic profiles and promising primary patency rates. A major predictor of technical failure and restenosis is the calcification of the target vessel. Recently, intravascular lithotripsy of calcified lesions at the femoropopliteal segment with the Shockwave® balloon was introduced as a feasible treatment option for these complex lesions. Finally, we also describe the Tack Endovascular System®, the first-of-its-type, for the repair of post-angioplasty dissections.Expert opinion: The use of innovative stent designs and novel drug-coating, the application of adjunctive intravascular lithotripsy, and the combined use of new devices treating complications might improve the overall outcomes of angioplasty, thereby promising favorable outcomes even for more complex lesions.

Real-World Results of Supera Stent Implantation for Popliteal Artery Atherosclerotic Lesions: 3-Year Outcome

BACKGROUND

Reports our experience for the first 50 cases of use of Supera stent for popliteal atherosclerotic lesions treatment.

METHODS

This prospective single-arm trial enrolled the first 50 limbs (46 patients) treated in our center with a Supera stent for symptomatic atherosclerotic disease of the popliteal artery. Also, a follow-up of 36 months is reported.

RESULTS

The mean preoperative ankle-brachial index increased from 0.38 ± 0.37 before intervention to 0.63 ± 0.46 postoperatively at 12 months (P = 0.014), 0.66 ± 0.39 at 24 months (P = 0.023), and 0.74 ± 0.46 at 36 months (P = 0.029). Primary patency at 12, 24, and 36 months were 89.6%, 72.3%, and 70.2%, and primary assisted patency was 93.8%, 87.2%, and 85.1%, respectively, by Kaplan-Meier estimates. After 3 years of follow-up, age <75 years (P = 0.034) and Trans-Atlantic Inter-Society Consensus (TASC)-II D lesions (P = 0.041) constituted risk factors for stent occlusion. During the follow-up of the patients, none of them developed stent fracture as evidenced on plain radiographs during follow-up. Implantation defects did not constitute a risk factor for stent restenosis.

CONCLUSIONS

Based on the results of this study, Supera stent has shown an excellent 3-year patency in this difficult-to-treat anatomic segment. In our experience, younger patients and complex lesions (TASC-II type D) were positive significant predictors for restenosis. In our cohort, post deployment stent conformation did not influence patency. Nevertheless, further investigations, including randomized studies comparing the Supera stent with other stent platforms, drug eluting angioplasty, or atherectomy devices, are mandatory.

Demystifying the Use of Self-Expandable Interwoven Nitinol Stents in Femoropopliteal Peripheral Arterial Disease

Femoropopliteal atherosclerosis affects a significant percentage of the world population, leading to intermittent claudication and critical limb ischemia. The femoropopliteal segment has a unique set of biomechanical challenges that must be considered and overcome for treatment. The use of stents is a reality and a necessity in peripheral interventions. The success of first-generation femoropopliteal stents was limited by their rigidity and deformability. The standard nitinol stents overcame certain biomechanical challenges because of their superelasticity and thermal shape memory, although stent fracture is still an issue. Therefore, interwoven nitinol stents with helical structure have been developed, borrowing the concept from biliary stents, aiming to provide good flexibility while still maintaining a uniform cell size and significant radial strength. This unique interwoven structure gains it advantage in the femoropopliteal region. The purpose of this review article is to investigate the current published evidence of the use of self-expandable interwoven nitinol stents in femoropopliteal arterial disease and compare them with other endovascular treatment options.

Efficacy of dextran and peptide-everolimus bi-directional stent

Everolimus inhibits stent restenosis and the WKYMV (fluorescein isothiocyanate) peptide promotes endothelial homing. Dextran is a natural polymer that is widely used as a pharmaceutical agent. The purpose of this study was to develop a double-drug-coated stent using a bidirectional coating system and to examine the surface shape with in vitro experiments. Stent length was 16 mm and strut thickness was 70 µm (Chonnam National University Hospital Tiger stent). Optical and scanning electron microscopy showed good coating without cracks or bubbles. Fluorescein isothiocyanate-peptide was dip-coated on the lumen and the abluminal surface was coated with everolimus and dextran. Stents were coated with dextran, everolimus, or everolimus-dextran. The radial force and flexibility were measured to determine the mechanical properties. Contact angle testing was performed in all groups. Dextran and peptide as hydrophilic substances and everolimus as a hydrophobic substance were each coated on cover glasses (cobalt-chromium). A10 and human umbilical vein endothelial cells were used in the experiments. Water and dimethyl sulfoxide served as a control, and three drug groups were tested: peptide-everolimus, everolimus-dextran, and peptide-everolimus-dextran. Immunocytochemistry was performed to assess cell adhesion. Light intensity was plotted according to the average on nuclear staining. Experiments were conducted using 5-bromo-2'-deoxyuridine to investigate A10 and human umbilical vein endothelial cell proliferation. Cell adhesion and proliferation of peptide-everolimus-dextran were inhibited at A10, and human umbilical vein endothelial cell was found to proliferate with cell adhesion. On conclusion, dextran and peptide-everolimus bidirectional stent is effective in re-endothelialization and inhibition of cell proliferation.

Directional atherectomy with antirestenotic therapy for the treatment of no-stenting zones

Endovascular treatment for peripheral artery occlusive disease carries unresolved problem of restenosis. Treatment modalities in areas of high mechanical stress like popliteal artery and common femoral artery remains challenging. New-generation devices improved the results of stent therapy in this anatomical territory, but could impact on future surgical options if they are needed. Vessel preparation prior to drug (paclitaxel)-coated balloons (DCB) angioplasty leads to better paclitaxel penetration into the arterial wall and improved drug uptake. The "leave nothing behind" strategies, DCB angioplasty and combined directional atherectomy (DA) and antirestenotic therapy (DAART), can theoretically overcome the problems caused by the mobility of the knee joint. However, calcified and longer lesions remain a challenging subset that is less responsive to DCBs, resulting in higher provisional stent rates. For the treatment of long and calcified femoropopliteal lesions, vessel preparation with DA before DCB angioplasty seems to be safe in mid-term follow-up and might have benefits in more challenging lesion subsets that are at higher risk for acute and chronic technical treatment failure of percutaneous transluminal angioplasty, including DCB angioplasty, such as severely calcified lesions. Treatment with DA+DCB resulted in both increased technical success and fewer flow-limiting dissections compared with treatment with DCB alone. In concept of "leave nothing behind" therapies for isolated popliteal artery lesions, DAART was associated with a higher primary patency rate than DCB angioplasty alone.

Balloon Angioplasty Versus Bailout Stenting for Isolated Chronic Total Occlusions in the Popliteal Artery

Aims:

Stenting of the popliteal artery (PA) is generally considered inappropriate due to the high mechanical stress and bending of the artery during knee flexion. Nevertheless, vessel recoil remains problematic following angioplasty procedure for chronic total occlusions (CTOs) and adjunctive stenting may be required. The purpose of this study is to compare balloon angioplasty alone versus bailout stenting for isolated CTO of the PA.

Materials and Methods:

Between March 2012 and October 2016, 43 patients were treated with percutaneous transluminal angioplasty with balloon alone (PTA, n = 16) or bailout stenting percutaneous transluminal angioplasty and stenting (PTAS, n = 27) for de novo CTO of PA. There was no statistically significant difference between both groups with regard to patient demographics and lesions characteristics (calcification severity and lesion length). The median lesion lengths were 67 mm (39.5-78.5) in the PTA group and 94 mm (50-114) in the PTAS group ( p = 0.14). The primary outcome measure was primary patency; secondary outcomes were technical success, primary assisted patency, major amputation, and increased Rutherford classification.

Results:

Technical success rate was 37% and 96.3% in the PTA and PTAS groups, respectively. There was no statistical difference in 12-month primary patency rate (65.8% versus 58.7%; p = 0.15) and primary assisted patency at 12 months (75.2 versus 69.2; p = 0.47) between the 2 groups. Freedom from target lesion revascularization at 12 months was not significantly different, with 85.7% and 81.6% ( p = 0.2) in the PTA and PTAS groups, respectively. One amputation occurred in the PTA group.

Conclusion:

This small cohort suggests that stenting as a bailout procedure in CTO of the PA provides similar results to successful balloon angioplasty. Stenting should only be performed after suboptimal balloon angioplasty with vessel recoil. Due to the large lost to follow-up, strong evidence of a therapy over the other cannot be formulated. Larger studies with longer and stronger follow-up are needed to confirm those results.

Endovascular treatment for the common femoral artery: is there a challenger to open surgery?

Common femoral artery (CFA) atherosclerotic lesions currently remain one of the last limitations for adoption of endovascular repair as the first-line treatment. The bulky, eccentric, heavily calcified character of the CFA plaques, frequent involvement of the femoral bifurcation, easy surgical accessibility and last but not least, favorable long-term outcomes still make CFA disease treatment part of the surgical domain. In the last 5 years, improvement of the endovascular equipment and technical skills of the operators have led to an increase in percutaneous CFA procedures. Especially the vascular mimetic implant Supera Peripheral Stent system (Abbott Vascular), with its extreme crush resistance (if correctly implanted), seems to be an ideal tool to deal with eccentric calcified plaques, crush risk and maintaining access possibilities. The multicentric, prospective, single arm VMI-CFA Trial evaluates the outcome of treatment of symptomatic (Rutherford 2-4) CFA stenotic or occlusive lesions with the Supera Peripheral Stent System. A 6-month cumulative primary patency rate of 100% is noticed, up to 210 days. The cumulative freedom from TLR rate is 100%. Four patients died, not procedure or device related. From a clinical point of view, a tremendous switch from Rutherford 2-4 towards Rutherford 0-1 happened. No procedure nor device related adverse events are noticed. These short-term data confirm the safety and feasibility of an endovascular approach with the Supera stent to the "no-stent zone" CFA. Of course 12- and 24-month data are essential to bring more clarification in this interesting field.

Drug-Coated Balloon Angioplasty in Atherosclerosis Patients With Popliteal Artery Involvement

Purpose: To investigate outcomes of drug-coated balloon (DCB) angioplasty in endovascular interventions including or restricted to the popliteal artery. Methods: A retrospective analysis was conducted of 266 patients [median age 72 years, interquartile range (IQR) 62, 78; 166 men] treated with DCB angioplasty in 281 de novo lesions including the popliteal artery between December 2011 and January 2015 at a single center. The median lesion length was 270 mm (IQR 150, 373). The study outcomes were primary patency and predictors of restenosis [reported as the hazard ratio (HR) with 95% confidence interval (CI)]. Results: The primary patency was 77.4% at a median 12.2 months (IQR 5.7, 18.8). Independent variables associated with restenosis included baseline Rutherford category (HR 1.36, 95% CI 1.05 to 1.77, p=0.02), reference vessel diameter (HR 0.77, 95% CI 0.63 to 0.95, p=0.02), dissection (HR 1.69, 95% CI 1.022.79, p=0.04), and standard nitinol stent use (HR 2.08, 95% CI 1.14 to 3.79, p=0.02). Conclusion: Outcomes after DCB angioplasty in lesions including the popliteal artery were acceptable compared with previous studies. Further investigation with long-term follow-up is needed to confirm these results.

Treatment of femoropopliteal lesions with the AngioSculpt scoring balloon – results from the Heidelberg PANTHER registry

Abstract. Background: Treatment of calcified femoropopliteal lesions remains challenging, even in the era of drug-eluting balloon angioplasty. Lesion recoil and dissections after standard balloon angioplasty in calcific lesions often require subsequent stent implantation. Additionally, poor patency rates in calcified lesions despite the use of drug-eluting balloons may be due to the limited penetration depth of the antiproliferative drug in the presence of vascular calcium deposits. Therefore, preparation of calcified lesions with the AngioSculpt™ scoring balloon might be a valuable option either as a stand-alone treatment, followed by drug-eluting balloon angioplasty or prior to subsequent stent deployment. Patients and methods: In this retrospective, single centre registry, 124 calcified femoropopliteal lesions were treated in 101 subsequent patients. All patients were treated with scoring balloon angioplasty, either alone, in combination with drug-eluting balloons, or prior to stent deployment. The primary outcome was safety and technical success during the index procedure as well as patency at six and 12 months, as evaluated by duplex sonography. Results: Successful scoring was safely performed in all 124 lesions with the AngioSculpt™ balloon. Overall primary patency after 12 months was 81.2 %. Patency rates did not differ significantly between the three treatment strategies. Degree of calcification did not predict patency. Improved clinical outcomes (Rutherford-Becker class and ankle-brachial index) were also observed in the study cohort. Conclusions: Preparation with the AngioSculpt™ scoring balloon offers a safe and valuable treatment option for calcified femoropopliteal lesions.

Angioplasty and stenting for the proximal anastomotic stenosis of a brachio-axillary bypass graft using a helical interwoven nitinol stent: A case report

RATIONALE

Thrombosis due to anastomotic site stenosis is the most common complication in patients with brachio-axillary arteriovenous graft (AVG). Intravascular stent placement may play a special role in the salvage of dialysis grafts that have been previously performed percutaneous angioplasty or surgical procedure on the graft. Herein, we applied a novel stent named Supera which has a high degree of flexibility and resistance to external compression for treating a patient with recurrent venous anastomotic stenosis of brachio-axillary AVG.

PATIENTS CONCERNS AND DIAGNOSES

We report a case of the patient with end-stage renal disease who presented with brachio-axillary AVG malfunction.

INTERVENTIONS

The patient underwent repeated percutaneous angioplasty with thrombectomy for total graft occlusion, and we placed the Supera stent to salvage the graft.

OUTCOMES

Postprocedural Doppler ultrasonography did not show any restenosis on the 1- and 3-month follow-up periods, and average flow volume in the stent was >1000 mL/min. And he has been on dialysis for 6 months without any problems after stent placement.

LESSONS

The Supera stent is a useful treatment option of interventional procedure for recurrent venous anastomotic stenosis of brachio-axillary AVG in the clinical practice.

One-Year Outcomes Following Directional Atherectomy of Popliteal Artery Lesions: Subgroup Analysis of the Prospective, Multicenter DEFINITIVE LE Trial

Purpose: To report the effectiveness of directional atherectomy for the treatment of popliteal artery occlusive disease. Methods: This subset of the prospective, multicenter, single-arm DEFINITIVE LE trial included 158 patients (mean age 72.0±10.9 years; 82 men) who underwent directional atherectomy in 162 popliteal artery lesions between 2009 and 2011. Forty-eight (30.4%) patients were suffering from critical limb ischemia (CLI). The mean lesion length was 5.8±3.9 cm; 38 (23.5%) arteries were occluded. The primary outcome measure for patients with intermittent claudication (IC) was duplex ultrasound–defined primary patency at 1 year; the outcome for subjects with CLI was freedom from major amputation of the target limb at 1 year. Outcomes and adverse events were independently assessed. Results: Procedure success (≤30% residual stenosis) was achieved in 84.4% of treated lesions; adjunctive stenting was required in 6 (3.7%) of the 162 lesions. The 1-year primary patency rate was 75.0% (IC patients 78.2% and CLI patients 67.5%, p=0.118). The freedom from major amputation in both cohorts was 100%. In both IC and CLI patients, significant improvements were demonstrated at 1 year in the Rutherford category, walking distance, and quality of life in comparison to baseline. Conclusion: This study indicates that directional atherectomy in popliteal arteries leads to favorable technical and clinical results at 1 year for claudicant as well as CLI patients.

Femoro-Supragenicular Popliteal Bypass with a Bridging Stent Graft in a Diffusely Diseased Distal Target Popliteal Artery: Alternative to Below-Knee Popliteal Polytetrafluoroethylene Bypass

Background

Lesions in distal target arteries hinder surgical bypass procedures in patients with peripheral arterial occlusive disease.

Methods

Between April 2012 and October 2015, 16 patients (18 limbs) with lifestyle-limiting claudication (n=12) or chronic critical limb ischemia (n=6) underwent femoral–above-knee (AK) polytetrafluoroethylene (PTFE) bypass grafts with a bridging stent graft placement between the distal target popliteal artery and the PTFE graft. Ring-supported PTFE grafts were used in all patients with no available vein for graft material. Follow-up evaluations assessed clinical symptoms, the ankle-brachial index, ultrasonographic imaging and/or computed tomography angiography, the primary patency rate, and complications.

Results

All procedures were successful. The mean follow-up was 12.6 months (range, 11 to 14 months), and there were no major complications. The median baseline ankle-brachial index of 0.4 (range, 0.2 to 0.55) significantly increased to 0.8 (range, 0.5 to 1.0) at 12 months (p<0.01). The primary patency rate at 12 months was 83.3%. The presenting symptoms resolved within 2 weeks.

Conclusion

In AK bypasses with a diffusely diseased distal target popliteal artery or when below-knee (BK) bypass surgery is impossible, this procedure could be clinically effective and safe when used as an alternative to femoral-BK bypass surgery.

Fracture of a Supera Interwoven Nitinol Stent After Treatment of Popliteal Artery Stenosis

Purpose: To present a Supera stent fracture following treatment of popliteal artery stenosis. Case Report: A 60-year-old man previously treated with angioplasty/stenting of a popliteal artery lesion with a Supera stent presented at 8 months with in-stent occlusion that proved to be secondary to stent fracture. Conclusion: Supera interwoven nitinol stents, despite having higher radial force and conformability than classic tube stents, are not free from fracture. Moreover, due to their peculiar structure, a break in these stents results in complete loss of integrity and consequent device collapse, thus jeopardizing endovascular recanalization and relining.

Directional Atherectomy With Antirestenotic Therapy vs Drug-Coated Balloon Angioplasty Alone for Isolated Popliteal Artery Lesions

Purpose: To report a single-center study comparing drug-coated balloon (DCB) angioplasty vs directional atherectomy with antirestenotic therapy (DAART) for isolated lesions of the popliteal artery. Methods: Seventy-two patients were treated with either DCB angioplasty alone (n=31) or with DAART (n=41) for isolated popliteal artery stenotic disease between October 2009 and December 2015. The majority of patients presented with lifestyle-limiting claudication (74% vs 86%, respectively). Vessel calcification (29% vs 29%, respectively), mean lesion length (47 vs 42 mm, respectively), and number of runoff vessels were comparable between the groups. The primary outcome measure was primary patency; secondary outcomes were technical success (<30% residual stenosis or bailout stenting), secondary patency, and freedom from clinically driven target lesion revascularization (TLR). Results: The technical success rate following DCB was 84% vs 93% (p=0.24) after DAART. The 12-month primary patency rate was significantly higher in the DAART group (65% vs 82%; hazard ratio 2.64, 95% confidence interval 1.09 to 6.37, p=0.021), while freedom from TLR did not differ between the 2 treatment strategies (82% vs 94%, p=0.072). Secondary patency at 12 months was identical for both groups (96% vs 96%). Although not statistically significant, bailout stenting was more common after DCB angioplasty (16% vs 5% for DAART, p=0.13) and aneurysmal degeneration of the popliteal artery was seen more often after DAART (7% vs 0% for DCB alone, p=0.25). Popliteal artery injury was observed in 2 patients treated using DAART (5% vs 0% for DCB alone, p=0.5), whereas distal embolization rates were comparable between the groups (3% for DCB alone vs 5% for DAART, p=0.99). Conclusion: In this study, the use of DAART was associated with a higher primary patency rate compared with DCB angioplasty for isolated popliteal lesions. Nonetheless, both treatment options were associated with excellent 12-month secondary patency. Aneurysmal degeneration of the popliteal artery and increased bailout stenting could compromise the outcomes of DAART and DCB, respectively.

A Real-World Experience With the Supera Interwoven Nitinol Stent in Femoropopliteal Arteries

Purpose: To evaluate the safety and midterm patency of the Supera interwoven nitinol stent in a real-world population and determine deployment and patient-related factors that may predispose to loss of patency. Methods: A retrospective analysis was conducted of 111 consecutive limbs from 97 patients (mean age 75.3 years; 68 men) with severe atherosclerotic disease of the superficial femoral and popliteal arteries that were treated with Supera stents between June 2012 and October 2014. Half the patients had claudication (56%); the remainder had rest pain (19%) and tissue loss (26%). Forty-eight (43%) lesions were chronic total occlusions, and more than half were classified as TransAtlantic Inter-Society Consensus C (22%) or D (30%). Results: All 146 Supera stents (1.32 stents per limb) were deployed successfully, extending over a mean length of 175.5±130.5 mm to treat lesions averaging 151.5±127.1 mm long. At 30 days, Kaplan-Meier estimated freedom from death, target lesion revascularization, and amputation was 97.3%. Primary patency and freedom from clinically driven target lesion revascularization rates were 87.1% and 95.0% at 6 months, respectively, and 78.9% and 87.6% at 12 months, respectively. Four distinct mechanisms for failure were identified in the 13 limbs in which patency was lost; stent intussusception (n=4), compromised inflow or outflow (n=2), gross oversizing (n=1), and neoplastic thrombophilia (n=1); the cause of 5 occlusions could not be identified. Conclusion: In this heterogeneous group that included long and complex atheromatous femoropopliteal lesions, the Supera stent achieved excellent clinical and patency results at 1 year. Further improvement may be achieved through careful patient selection and the avoidance of deployment pitfalls.

Supera self-expanding stents for endovascular treatment of femoropopliteal disease: a review of the clinical evidence

Femoropopliteal lesions account for a significant proportion of endovascular interventions for peripheral artery disease in patients with disabling claudication or chronic limb ischemia. The femoropopliteal artery crosses two joint structures (hip and knee joints) and courses through the muscular adductor canal in the thigh, which places the artery at increased biomechanical stress. There is a critical need for stent platforms with a reduced risk of stent fracture while maintaining patency during long-term follow-up. The Supera peripheral stent system has a braided nickel–titanium alloy stent designed to withstand the unique stressors along the course of the femoropopliteal artery. This design may be associated with improved patency in association with reduced stent fracture rates on short- and medium-term follow-up. Further studies, including randomized controlled studies, comparing the Supera interwoven nickel–titanium alloy stent system with other stent platforms and angioplasty alone are needed.

Percutaneous endovascular treatment of peripheral arterial disease in Germany

PURPOSE

The general distribution of balloon angioplasty, stenting and other endovascular interventions in treating peripheral arterial disease (PAD) is unclear.

METHODS AND RESULTS

We used national statistics (DRG statistics) published by the Federal Statistical Office including data from almost all hospitals in Germany to calculate the rates and types of lower extremity endovascular procedures in 2012. In 2012 150,503 peripheral endovascular procedures were documented in Germany. The predominant procedures were percutaneous transluminal angioplasty (PTA) with 86.0% followed by thrombolysis with 7.2% and thrombectomy with 2.9%. In 50,092 (33.3%) of all peripheral endovascular procedures performed in the lower limb arteries a stent was placed: 66.7% in iliac, 34.3% in femoro-popliteal and 9.7% in cruro-pedal procedures. From these 50,092 procedures DES were coded in 3063 (6.1%) and covered stents in 1841 (3.7%). The highest rate of covered stents was placed in the aorta (8.6%) but the highest rate of DES was in the cruro-pedal arteries (23.1%).

CONCLUSION

Pure PTA is still the most frequently performed procedure in peripheral arteries and in only one third of all procedures was a stent placed in Germany in 2012.

Stenting of femoropopliteal lesions using interwoven nitinol stents

OBJECTIVE

The Supera stent (Abbott Laboratories, Abbott Park, Ill) has a unique biomimetic design allowing axial and longitudinal flexibility and fracture resistance. The aim of this retrospective study was to assess the midterm patency of Supera stents used to treat patients with superficial femoral and popliteal arterial disease by a single practice.

METHODS

From April 2010 to December 2011, 53 patients and 59 limbs with symptomatic femoropopliteal lesions underwent angioplasty and stenting with the Supera stent. Five patients had no follow-up and were excluded. Demographics of the patients, radiographic images, morphologic features of the lesions, procedural reports, reinterventions, and follow-up clinical visit notes were reviewed. Primary patency was defined as clinical resolution of symptoms with no secondary interventions. Primary and secondary patency rates at 12, 24, and 36 months were estimated by Kaplan-Meier analysis.

RESULTS

A total of 48 patients (42 men, six women; 54 limbs; mean age, 64.3 years [range, 51-87]) received Supera stents and had at least one follow-up visit as part of their treatment for femoropopliteal disease. Primary indications for intervention included claudication, rest pain, and tissue loss, at rates of 54% (29 of 54), 26% (14 of 54), and 20% (11 of 54), respectively; 22% of lesions were TransAtlantic Inter-Society Consensus type A or B and 78% were type C or D. Mean lesion length was 24.0 cm (range, 3-51). Mean follow-up was 27.5 months (range, 1-45). The ankle-brachial index increased from 0.58 ± 0.20 preoperatively to 0.77 ± 0.18 postoperatively (P = .00004). Primary, primary assisted, and secondary patency rates at latest follow-up were 79.6%, 88.9%, and 92.3%, respectively. Cumulative primary patency rates by Kaplan-Meier analysis at 12, 24, and 36 months were 85.6%, 83.1%, and 76.7%, respectively. Secondary patency rates by Kaplan-Meier estimates at 12, 24, and 36 months were 93.8%, 93.8%, and 89.3%, respectively. No stent fractures were found at the time of any reinterventions. Long lesions >30 cm (n = 18) showed equivalent patency to lesions of 1 to 15 cm (n = 18) and lesions 15 to 30 cm in length (n = 18).

CONCLUSIONS

Our midterm results show that Supera stents are durable in treating femoropopliteal lesions, with notably high patency rates in patients with long lesion lengths.

Stent Placement vs. Balloon Angioplasty for Popliteal Artery Treatment

Purpose: To investigate the 2-year technical and clinical results of primary nitinol stent placement in comparison with percutaneous transluminal angioplasty (PTA) in the treatment of de novo lesions of the popliteal artery. Methods: The ETAP study (Endovascular Treatment of Atherosclerotic Popliteal Artery Lesions: balloon angioplasty vs. primary stenting; www.ClinicalTrials.gov identifier NCT00712309) is a prospective, randomized trial that enrolled 246 patients (158 men; mean age 72 years) who were randomly assigned to receive a nitinol stent (n=119) or PTA (n=127) for lesions averaging 42.3 mm in length. The results of the primary study endpoint were published. Secondary outcome measures and endpoints included primary patency (freedom from duplex-detected target lesion restenosis), target lesion revascularization (TLR), secondary patency, changes in ankle-brachial index and Rutherford class, and event-free survival (freedom from target limb amputation, TLR, myocardial infarction, and death). Results: In total, 183 patients (89 stent and 94 PTA) were available for the 2-year analysis. The primary patency rate was significantly higher in the stent group (64.2%) than in the PTA group (31.3%, p=0.0001). TLR rates were 22.4% and 59.5%, respectively (p=0.0001). When provisional stent placement in the PTA arm was not considered as TLR and loss in patency, the differences prevailed between the study groups but were not significant (64.2% vs. 56.1% for primary patency, respectively; p=0.44). A significant improvement in ABI and Rutherford category was observed at 2 years in both groups. Conclusion: In treatment of obstructive popliteal artery lesions, provisional stenting reveals equivalent patency in comparison to primary stenting. However, the 2-year results of this trial suggest the possibility of a shift toward higher patency rates in favor of primary stenting.

Atheromatous occlusive lesions of the popliteal artery treated with stent grafts: predictive factors of midterm patency

BACKGROUND

Because of its location, the popliteal artery is exposed to important biomechanical constraints, inducing a specific risk of thrombosis of stents, little studied in the literature. The objective of this monocentric retrospective study was to evaluate the patency of stents implanted in the popliteal artery to treat atheromatous lesions and the risk factors predisposing to thrombosis.

METHODS

Between January 2009 and July 2013, all the patients receiving stents for a residual stenosis or a complication of angioplasty in the popliteal artery or the distal anastomosis of a femoropopliteal bypass were included retrospectively and in an intention to treat. Forty-six patients (17 women), with a 71.5 years median age (range, 45-90 years), including 17 diabetic patients (37%) and 7 hemodialysis patients (15%), were operated in 51 limbs for claudication (n = 25, 49%), critical ischemia (n = 18, 35%), or acute ischemia (n = 8, 16%). Thirty stenoses >70% (59%) and 21 thromboses (41%) were treated with 56 autoexpandable stents, with an average diameter of 6 mm (range, 5-8 mm) and an average length of 5 cm (range, 4-15 cm), including 39 lesions in P1 (above the patella), 8 in P2 (articular), and 4 in P3 (distal popliteal artery). The following factors were analyzed according to univariate and multivariate models: age, gender, Society for Vascular Surgery score, symptomatology, type and location of lesion, number of stents deployed, and dimension of stents.

RESULTS

Technical success was of 98% (n = 50), including 1 insufficient result of the endovascular treatment. At 30 days, one patient treated for critical ischemia died (2%) and one residual popliteal stenosis was treated by bypass (2%). After a 27.6 ± 10.07 month follow-up, restenosis (>50%) was detected in 5 cases including 4 asymptomatic and a popliteal thrombosis occurred in 9 cases, including 3 asymptomatic cases. Eight secondary interventions were necessary, including 4 endovascular procedures, 3 bypasses, and only 1 major amputation (thigh). The primary and secondary patencies at 12 months and 24 months were 80% and 65%, and 90% and 74%, respectively. The multivariate analysis showed that the type of lesion (stenosis versus occlusion; odds ratio [OR], 5.1; 95% confidence interval [CI], 1.2-22.9, P = 0.032) and the number of stents implanted (1 vs. 2 stents; OR [95% CI], 12.7 [1.8-88.5]; P = 0.011) were independent predictive factors of secondary thrombosis.

CONCLUSIONS

The endovascular treatment of the atheromatous popliteal lesions appears to be a satisfactory alternative. The implantation of 1 stent in the popliteal artery is recommended in the event of popliteal occlusion, whereas for a stenosis, it must be reserved for patients with residual stenosis or in the event of complications of angioplasty, such as dissection or elastic recoil. Stent must be single, with deployment of a long stent in the event of long lesion.

SUPERA interwoven nitinol Stent Outcomes in Above-Knee IntErventions (SAKE) study

PURPOSE

To report experience with the novel interwoven-wire self-expanding nitinol SUPERA stent (IDEV Technologies, Inc/Abbott Laboratories, Inc, Webster, Texas) for the treatment of severely diseased superficial femoral and popliteal arteries.

MATERIALS AND METHODS

Consecutive patients with severely diseased superficial femoral and popliteal arteries who received SUPERA stents (n = 80 patients [98 limbs]; mean age, 70.8 y; 80% male) were retrospectively identified. Patients were followed for an average of 14.3 months after intervention.

RESULTS

Total occlusions were present in 39% of the lesions, 21% had tissue loss, and 61% demonstrated calcification on fluoroscopy. Patients were prescribed dual antiplatelet therapy (aspirin and clopidogrel) for at least 30 days unless contraindicated, followed by aspirin alone indefinitely. The mean (± SD) lesion length was 143 mm (± 98). Based on need for clinical intervention, primary patency was 96.9% at 6 months and 85.8% at 12 months (Kaplan-Meier estimates). Assisted primary patency and secondary patency rates at 12 months were 96.8% and 100%, respectively. Ankle-brachial index increased from 0.60 at baseline to 0.83 at last follow-up (P < .001). No stent fractures were found by fluoroscopy inspection in 19 limbs (16 patients) that required reintervention.

CONCLUSIONS

Based on experience with multiple operators at a single clinical center, the interwoven nitinol stent design provides a viable option for high-grade obstructive disease in the femoropopliteal artery.

Endovascular treatment of lesions in the below-knee popliteal artery

BACKGROUND

Endovascular interventions are increasing; however, there are little data regarding outcomes of complex interventions involving the below-knee popliteal/P3 artery. This study evaluated the short-term and long-term results and predictors of success of below-knee popliteal artery endovascular interventions.

METHODS

This was a retrospective review of a prospectively maintained endovascular lower extremity database of all patients with below-knee popliteal interventions from 2004 to 2012. Patient demographics, angiographic findings, interventions, primary and secondary patency, limb loss, and mortality were recorded. Analysis was performed using Kaplan-Meier life-table and multivariate analysis, with P < .05 indicating significance.

RESULTS

There were 221 patients (56% male) with below-knee popliteal/P3 artery lesions. Mean age was 73 ± 11.2 years. Claudication was present in 22% and critical limb ischemia (CLI) in 78%. Mean lesion length was 10 ± 8.5 cm, with 45% having total occlusions. Treatment included percutaneous transluminal angioplasty (PTA) with or without a stent (47%), atherectomy (ATH) with or without PTA/stent (52%), and stenting with PTA and ATH (3%). Complications included embolization (0.4%), hematoma (2.7%), pseudoaneurysm (1.3%), and dissection (7%). Freedom from restenosis (peak systolic velocity ratio >2.4) was 65% at 1 year. Independent predictors of restenosis were CLI (hazard risk [HR], 4.4; 95% confidence interval [CI], 1.9-9.9) and stenting combined with PTA and ATH (HR, 2.7; 95% CI, 1.01-7.4). Primary assisted and secondary patencies were 95% and 85% at 1 year. ATH with PTA had lower short-term restenosis in diabetic patients compared with nondiabetic patients (95% vs 78% at 4 months). Limb loss was 18% at 4 years. Mortality was 24% at 4 years. Statin use was protective against primary restenosis (HR, 0.39; 95% CI, 0.23-0.67) and death (HR, 0.5; 95% CI, 0.28-1.0).

CONCLUSIONS

Endovascular intervention for lesions involving the below-knee popliteal artery is a safe and effective therapy for claudication and CLI. Diabetic patients benefit most from ATH with PTA. Statin use is protective against restenosis and mortality and should be the standard of care in patients undergoing peripheral endovascular interventions.

Evaluation of the 4-French Pulsar-18 Self-expanding Nitinol Stent in Long Femoropopliteal Lesions

PURPOSE

To evaluate the patency and the freedom of target lesion revascularization of the 4-French Pulsar-18 self-expandable (SE) nitinol stent for the treatment of long femoropopliteal occlusive disease in a two-center, prospective, all-comers registry with a follow-up period of 12 months.

METHODS

This registry enrolled 36 patients with symptomatic femoropopliteal long lesions for recanalization and implantation of the 4-French Pulsar-18 SE nitinol stent. Routine follow-up examination including duplex ultrasound was performed after 6 and 12 months. Primary patency was defined as no binary restenosis on duplex ultrasound (Peak systolic velocitiy ration (PSVR) <2.5) and no target lesion revascularization was performed within 12 months’ follow-up. No drug-eluting devices were allowed in this registry.

RESULTS

Average lesion length of the femoropopliteal segment was 182.3 ± 51.8 mm. Mean stent implantation length was 181.5 ± 35.4 mm. Total occlusion was present in 46 of the 48 (95.8%) treated lesions. Involvement of popliteal segment I–III was present in 3 (6.3%) lesions. The primary patency after 6 and 12 months was 87.5% and 85.4%, respectively. The clinically driven overall freedom from target lesion revascularization (fTLR) was 89.6% after 6 months and 87.5% after 12 months. ABI, pain-free walking distance and Rutherford category, all improved significantly (P < 0.001) after 6 and 12 months. The primary patency rate in patients with diabetes (P = 0.18) and renal insufficiency (P = 0.3) was not significantly lower as compared to the overall primary patency.

CONCLUSIONS

In this two-center, all-comers registry, the use of the Pulsar-18 SE nitinol stent for endovascular intervention of femoropopliteal disease with a mean lesion length of 182.3 ± 51.8 mm showed promising primary patency and fTLR rates after 6 and 12 months. Diabetes and renal insufficiency had no negative impact on the patency rate.

Stent Placement Versus Balloon Angioplasty for the Treatment of Obstructive Lesions of the Popliteal Artery

Background—

Stenting has been shown to improve patency after femoral artery revascularization compared with balloon angioplasty. Limited data are available evaluating endovascular treatment for obstructive lesions of the popliteal artery.

Methods and Results—

This prospective, randomized, multicenter trial compared primary nitinol stent placement to percutaneous transluminal balloon angioplasty in patients with peripheral artery disease Rutherford-Becker class 2 to 5 who had a de novo lesion in the popliteal artery. The primary study end point was 1-year primary patency, defined as freedom from target-lesion restenosis (luminal narrowing of ≥50%) as detected by duplex ultrasound. Secondary end points included target-lesion revascularization rate and changes in Rutherford-Becker class. Provisional stent placement was considered target-lesion revascularization and loss of primary patency. Two hundred forty-six patients were included in this trial. The mean target-lesion length was 42.3 mm. One hundred ninety-seven patients were available for the1-year follow-up. The 1-year primary patency rate was significantly higher in the group with primary nitinol stent placement (67.4%) than in the percutaneous transluminal balloon angioplasty group (44.9%, P =0.002). Target-lesion revascularization rates were 14.7% and 44.1%, respectively ( P =0.0001); however, when provisional nitinol stent placement was not considered target-lesion revascularization and loss in patency, no significant differences prevailed between the study groups (67.4% versus 65.7%, P =0.92 for primary patency). Approximately 73% of patients in the percutaneous transluminal balloon angioplasty group and 77% in the nitinol stent group showed an improvement of ≥1 Rutherford-Becker class ( P =0.31).

Conclusions—

Primary nitinol stent placement for obstructive lesions of the popliteal artery achieves superior acute technical success and higher 1-year primary patency only if provisional stenting is considered target-lesion revascularization. Provisional stenting as part of a percutaneous transluminal balloon angioplasty strategy has equivalent 1-year patency and should be preferred over primary stenting.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00712309.