Current state of endovascular treatment of femoro-popliteal artery disease

Navigating complexity: The Supera's triumph in femoropopliteal lesions

INTRODUCTION

The femoropopliteal sector endovascular treatment is particularly challenging due to its high tortuosity and torsional forces. Better results are still needed to ensure the long-term patency of stenting in this area. The Supera stent appears to change this paradigm.

METHODS

This single-center retrospective cohort study aims to evaluate the efficacy and safety of femoropopliteal stenting with Supera in a real-world population. Seventy-nine patients were treated between January 2015 and December 2020, and the results are reported with a median follow-up of 28 months.

RESULTS

Indications for revascularization were chronic limb-threatening ischemia with tissue loss (73.6%) or ischemic rest pain (17.7%) and claudication (7.6%). Thirty-six patients (45.6%) were classified as GLASS stage III according to the Global Limb Anatomic Staging System, with 65.8% and 30.4% in grades 3 and 4 of femoropopliteal and infrapopliteal sectors, respectively. The 36-month primary, primary-assisted, and secondary patency rates were 68.6%, 72.0%, and 79.0%, respectively, with an amputation-free survival rate of 86.6%. There was no significant difference between primary patency rates in GLASS stages I-II compared with GLASS stage III (36-month primary patency rates of 72% vs 63% respectively, p = 0.342) nor in amputation-free survival (88% vs 84%, p = 0.877). After adjusting for potential confounders, only the stent conformation significantly affected the primary patency rates, with a higher hazard of reintervention for the elongated (HR = 3.179; p = 0.36; CI 1.081-9.347) and the compressed (HR = 3.014; p = 0.42; CI 1.039-8.746) forms.

CONCLUSIONS

The 36-month patency of the Supera stents in our real-world cohort was similar to other reported series. The GLASS stage did not interfere with the stent patency, proving it is a good choice even in the most adverse anatomy patients. Only the non-nominal stent conformation affected the primary patency rates in our patients.

Optimized drug-coated balloon angioplasty of the superficial femoral and proximal popliteal arteries using the Tack Endovascular System: Tack Optimized Balloon Angioplasty (TOBA) III 24-month results in standard and long lesions

OBJECTIVE

The Tack Endovascular System is a minimal-metal dissection repair device that is purpose-built to treat post-percutaneous angioplasty (PTA) arterial dissections in patients with peripheral arterial disease (PAD). The Tack Optimized Balloon Angioplasty (TOBA) III trial evaluated the safety and effectiveness of the Tack Endovascular System in patients with superficial femoral artery (SFA) and/or proximal popliteal artery (PPA) dissection after PTA with a drug-coated balloon (DCB). The objective of this study is to report the results in the standard- (SL) and long-lesion (LL) cohorts through 24 months.

DESIGN

The TOBA III study was a prospective, multicenter, single-arm study including patients suffering from Rutherford category 2-4 PAD. Outcomes were assessed according to pre-specified lesion length in SL ( ≥ 20 mm and ≤150 mm) and LL ( > 150 mm and ≤250 mm) cohorts. Follow-up was through 24 months.

RESULTS

TOBA III enrolled 201 patients, 169 patients in the SL cohort and 32 in the LL cohort. At 24 months, the Kaplan-Meier estimates of freedom from major adverse events were 91.7% and 82.6% for the SL cohort and LL cohort, respectively. Kaplan-Meier estimates of freedom from clinically driven-target lesion revascularization (CD-TLR) were 92.3% in the SL cohort and 82.6% in the LL cohort. At 24 months, 78.8% of SL patients and 69.2% of LL patients experienced an improvement of >2 Rutherford categories (both cohorts p < 0.001). The baseline ankle-brachial index improved from 0.68 ± 0.18 to 0.93 ± 0.16 in the SL (p < 0.001) and from 0.62 ± 0.23 to 0.87 ± 0.15 in the LL cohort (p < 0.001) at 24 months.

CONCLUSION

The 24-month results of the TOBA III trial support the safety and effectiveness of the Tack Endovascular System in patients who required post-PTA dissection repair in the SFA and PPA following DCB angioplasty for claudication and rest pain. In both the SL and LL cohorts, Tack placement was associated with sustained freedom from CD-TLR through 24 months as well as sustained improvements in Rutherford categories, ankle-brachial index, and quality of life.

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.

Popliteal endarterectomy at the leg level with venous enlargement patch: about 14 cases

The incidence of lesions of the popliteal artery below the knee constitutes one of the greatest problems in revascularization of the lower limb. Firstly, this segment constitutes the departure of the leg tripod, decisive crossroads for a subsequent endovascular intervention. On the other hand, it constitutes a fairly used relay point in the event of an indication for a pedal bypass. It is assumed that the performance of a popliteal endarterectomy with an enlargement by medial approach in patients with a localized lesion at this level constitutes an effective therapeutic approach and can facilitate any gesture of crural bypass or endovascular dilation later. We present a retrospective review of all patients who underwent popliteal endarterectomy with venous patch plasty for localized popliteal disease in our institution over the past 3 years.

The Ability to Look Beyond: The Treatment of Peripheral Arterial Disease

This paper offers a practical overview of the contemporary management of patients with peripheral arterial disease presenting intermittent claudication (IC), including clinical and instrumental diagnosis, risk factors modification, medical management, and evidence-based revascularization indications and techniques. Decision making represents a crucial element in the management of the patient with IC; for this, we think a review of this type could be very useful, especially for non-vascular specialists.

Results of Excimer Laser Ablation Combined with Drug-Coated Balloon for Atherosclerotic Obliterans of Lower Extremity and Risk Factors for Loss of Primary Patency

BACKGROUND

The results of excimer laser ablation (ELA) combining with drug-coated balloon (DCB) in the treatment for atherosclerotic obliterans (ASO) remains unclear.

METHODS

Retrospectively enrolled patients who underwent ELA combined with DCB in 2 centers. The primary endpoint was primary patency, and secondary endpoints included technical success, procedure-related complications, major amputation, clinically driven target lesions reintervention (CD-TLR), measurements of ankle-brachial index (ABI), and quality of life (QoL).

RESULTS

102 patients were enrolled. The primary patency was 86.7% (95% confidence interval [CI]: 72.9%-89.0%) at 12 months and 82.6% (95% CI: 78.2%-92.1%) at 24 months. The freedom from reintervention was 87.8% (95% CI: 79.5%-92.9%) at 12 months and 86.6% (95% CI: 78.1%-92.0%) at 24 months. The ABI measurement and QoL were significantly improved at each follow-up point. Sixteen (15.7%) patients lost the primary patency. Patients losing the primary patency demonstrated higher Rutherford class (P = 0.004), worse runoff (P < 0.001), higher Peripheral Arterial Calcium Scoring System (PACSS) (P < 0.001), and smaller ratio of tube diameter to reference vessel diameter (TD/RVD) (P < 0.001) compared with patients without losing it. The run-off ≥7 (adjusted odds ratio [aOR]: 34.3; 95% CI: 2.9-398.3; P = 0.005) and TD/RVD <4.9 (aOR: 24.7; 95% CI: 1.7-359.5; P = 0.019) were independent risk factors for loss of primary patency.

CONCLUSIONS

ELA combined with DCB seemed an effective and safe treatment for ASO of lower extremity, and it could not only reduce the implantation of stent but significantly improve QoL. The run-off ≥7 and TD/RVD <4.9 were independent risk factors for loss of primary patency.

Treating post-angioplasty dissection in the femoropopliteal arteries using the tack endovascular system: Tack optimized balloon angioplasty II 24-month results

OBJECTIVES

The TOBA (Tack Optimized Balloon Angioplasty) II trial is a prospective, single-arm, multicenter study that investigated Tack treatment for patients with dissection after angioplasty in the superficial femoral artery and/or proximal popliteal artery. The Tack device is a nitinol-based, short (6 mm), stent-like implant with low outward force that can be deployed in a targeted fashion to treat vascular dissection. TOBA II primary results through 12 months have been published previously. This report provides follow-up safety and efficacy results through 24 months (RC).

METHODS

The TOBA II trial enrolled 213 patients with Rutherford classification 2 to 4 and a de novo or non-stented restenotic lesion in the superficial femoral artery and/or proximal popliteal artery who developed a dissection of any grade after treatment with plain balloon or drug-coated balloon (DCB) angioplasty. Participants were followed for 30 days, 6 months, 12 months, 24 months, and 36 months following the procedure. Evaluations included clinically driven target lesion revascularization (CD-TLR), ankle-brachial index, Rutherford classification, peripheral artery questionnaire, quality of life assessed by the EQ-5D-3L, and the Walking Impairment Questionnaire.

RESULTS

At enrollment, mean age was 68.2 ± 9.1 years, 70.9% were male, and 95.8% of patients were categorized as RC 2 or 3. The distribution of balloon types in the study were standard balloons: 42.3%; and drug-coated balloons: 57.7%. At 24-month follow-up, 167 patients (78.4%) had available data. The overall survival rate at 24 months was 95.4% and there were no major amputations during this time. After 24 months of follow-up, the Kaplan-Meier freedom from CD-TLR was 77.7%. Rutherford classification, ankle-brachial index, and quality of life were significantly improved compared with baseline through 24 months.

CONCLUSIONS

The TOBA II 24-month data demonstrate durable intermediate-term outcomes with the use of the Tack Endovascular System. Tack deployment was a safe and effective therapeutic option for dissection repair following angioplasty.

Patterns of Care and Outcomes of Ambulatory Endovascular Interventions in Lower Extremity Peripheral Arterial Disease

Lower extremity endovascular intervention (LE-EVI) is gaining popularity as the primary treatment modality for patients with symptomatic peripheral artery disease refractory to noninvasive management. We examined the contemporary patterns of care, regional variation, and outcomes of ambulatory LE-EVI in the United States. The National Ambulatory Surgery Sample was analyzed to identify 266,563 records with peripheral artery disease and LE-EVI between January 1, 2016 and December 31, 2017. The mean age of the study cohort was 68.9 years and 40.5% were women. The majority of the endovascular interventions were performed at large (58.1%), urban teaching (64.1%), private not-for-profit (76.8%) centers, and the southern region accounted for most cases (43%). Periprocedural major adverse renal and cardiovascular events and other complications were 0.5% and 3.3%, respectively. Most patients (97.6%) were discharged home after the procedure. Age, female gender, uncontrolled hypertension, ischemic heart disease, heart failure, arrhythmia, chronic kidney disease, malnutrition, non-Medicare insurance, private for-profit, urban teaching facilities, and southern and midwest regions were associated with higher odds of major adverse renal and cardiovascular events. The mean charges per patient encounter were $56,500, with significant differences across various patient and facility characteristics. In conclusion, our study demonstrates the use, patterns of care, financial aspect, and overall safety of ambulatory LE-EVIs in a real-world setting.

One single drug-coated balloon for all shapes/diameters? Neointimal proliferation inhibition in porcine peripheral arteries

BACKGROUND

Long diseased vessel segments of peripheral arteries may display irregular shapes with different diameters. The aim of this study was to investigate inhibition of neointimal proliferation in porcine peripheral vessels with different diameters covered by one single hyper-compliant drug-coated balloon (HCDCB), compared to conventional drug-coated balloons (DCB), each selected according to the respective vessel diameter.

METHODS AND RESULTS

Neointimal proliferation was stimulated in proximal and distal segments of the peripheral arteries by balloon overstretch and stent implantation. Inhibition of neointimal proliferation by one single HCDCB was compared to two vessel diameter-adjusted DCB per artery and to one single uncoated hyper-compliant balloon (HCB). Sixteen HCB, 16 HCDCB, and 32 DCB were used in 16 arteries each. Quantitative angiography (QA), optical coherence tomography (OCT) and histology showed a similar anti-restenotic effect for one HCDCB compared to two vessel diameter-adjusted DCB in narrow distal and wider proximal segments (QA diameter stenosis: 18.7±12.3% vs. 22.8±15.5%, p = 0.535; OCT area stenosis: 21.4±11.6% vs. 23.6±12.3%, p = 0.850; histomorphometry diameter stenosis: 27.5±7.1% vs. 26.9±8.0%, p = 0.952) and indicated significant inhibition of neointimal proliferation by HCDCB vs. uncoated HCB (QA diameter stenosis: 18.7±12.3% vs. 30.3±16.7%, p = 0.008; OCT area stenosis: 21.4±11.6% vs. 34.7±16.0%, p = 0.004; histomorphometry diameter stenosis: 27.5±7.1% vs. 32.5±8.5%, p = 0.038).

CONCLUSIONS

HCDCB were found to be similar effective as DCB in inhibiting neointimal proliferation in vessel segments with different diameters. One single long HCDCB may allow for treatment of segments with variable diameters, and thus, replace the use of several vessel diameter-adjusted DCB.

Is open surgery still the first line of treatment for long femoropopliteal lesions?

INTRODUCTION

Treatment of long femoropopliteal lesions remains a challenge for vascular physicians as patients often present with multilevel complex pathologies and consequently face a high amputation risk and associated mortality. This review aimed to assess the current state of optimal revascularizations for the treatment of long femoropopliteal lesions.

EVIDENCE ACQUISITION

An online literature research of medical databases for original articles and review articles on open and endovascular revascularization of femoropopliteal lesions was conducted using mesh terms.

EVIDENCE SYNTHESIS

There has been an accumulation of evidence over the last years that endovascular treatment is a feasible and enduring alternative to open surgery for treatment of long femoropopliteal lesions if the lesions are restricted to the superficial femoral artery. But when disease extends to the infragenual level venous bypass remains superior with regards to long-term patency, clinical improvement and limb-salvage.

CONCLUSIONS

While the role of venous bypass as a first-line treatment might be declining, especially in frail patients or claudicants, the superior clinical improvement and amputation-free survival highlighted in several trials, demonstrate the relevance of bypass surgery. More randomized clinical trials are needed to verify the non-inferiority of endovascular treatment options to open surgery, especially when arterial disease extends below the knee.

Evaluation of safety and efficacy of the S.M.A.R.T.® Flex Vascular Stent System (OPEN study)

OBJECTIVES

The OPEN study evaluated the safety and efficacy of the S.M.A.R.T.® Flex Vascular Stent System in patients with femoropopliteal arterial disease.

BACKGROUND

Long-term data on endovascular treatments of femoropopliteal arterial disease are required to establish the repair durability.

METHODS

The OPEN study was a multicenter, single-arm, prospective study comparing primary safety and efficacy outcomes to performance goals (PG) developed for bare nitinol stents. Patients with symptoms due to a single, ≤180 mm length, de novo femoropopliteal arterial lesion with >70% stenosis were enrolled were enrolled and followed for 36 months. Subjects with lesions ≤150 mm served as the initial comparison cohort for the PG (other cohorts were analyzed if the PG was met).

RESULTS

257 subjects with lesions ≤180 mm were enrolled. The mean lesion length was 71 ± 46, and 52.5% had severe claudication. The primary safety endpoint (freedom from all-cause death, index limb amputation, and target lesion revascularization [TLR] through 30 days) was met in 98.8% (96.5%, 99.6%) of subjects in the comparison cohort, meeting the PG (88.0%). The primary efficacy endpoint (comparison cohort vessel patency at 12 months) was 68.4% (61.1%, 74.8%), where the lower limit of the 95% confidence interval did not meet the 66.0% PG. Freedom from TLR in the per-protocol cohort at 12-, 24-, 36-month was 84.7%, 74.6%, and 72.8%, respectively. The 24-month stent fracture rate was 4.3%, with no new fractures identified at 36 months.

CONCLUSION

The results show promising long-term safety and effectiveness for the S.M.A.R.T.® Flex Vascular Stent System in patients with femoropopliteal arterial disease.

Twelve-month safety and effectiveness of TCD-17187 drug-coated balloon for the treatment of atherosclerotic lesions in the superficial femoral and proximal popliteal artery

PURPOSE

The aim of this preapproval trial was to evaluate the 12-month safety and effectiveness of the TCD-17187 drug-coated balloon (DCB) for the treatment of atherosclerotic lesions in the superficial femoral artery (SFA) and/or proximal popliteal artery (PA).

METHODS

This was a prospective, multicenter, core laboratory adjudicated, single-arm trial. From October 2019 to November 2020, a total of 121 symptomatic peripheral artery disease patients with SFA and/or proximal PA lesions were enrolled. The primary effectiveness endpoint was 12-month primary patency defined as freedom from restenosis as determined by duplex ultrasonography in the absence of clinically driven target lesion revascularization (CD-TLR). The safety endpoint was the major adverse event (MAE) rate defined as freedom from a composite of device- and procedure-related death within 30 days, and index limb major amputation and/or CD-TLR through follow-up.

RESULTS

Average age was 74.5 ± 7.3 years and the frequency of diabetes mellitus was 67.5%. Average lesion length and vessel diameter were 106.0 ± 52.6 and 5.2 ± 0.8 mm, respectively. The frequency of chronic total occlusion and bilateral calcification was 17.5% and 50.8% of patients, respectively. The 12-month primary patency rate calculated by Kaplan-Meier analysis was 81.1%, while 12-month freedom from CD-TLR was 95.8%. The MAE rate at 30 days was 1.7% and all events comprised CD-TLR. There were no instances of device- or procedure-related deaths, major amputations, or thrombosis throughout the 12-month evaluation period.

CONCLUSION

This preapproval trial confirmed the safety and effectiveness of TCD-17187 DCB in the treatment of atherosclerotic lesions in the SFA and/or proximal PA.

Long-Term Results of Endovascular Treatment with Nitinol Stents for Femoropopliteal TASC II C and D Lesions

Background and Objectives: The feasibility of endovascular treatment (EVT) for Trans-Atlantic Inter-Society Consensus (TASC) II C and D femoropopliteal artery lesions has been described, but no prospective study has performed a long-term follow-up. The aim of this study was to report the long-term results of nitinol stents (NS) for the treatment of long femoropopliteal lesions. Materials and Methods: A single-center prospective, randomized controlled trial (RCT) comparing EVT with NS and vein bypass surgery was previously performed. The EVT group’s follow-up was extended and separately analyzed with primary patency as the primary endpoint. The secondary endpoints were technical success, secondary patency, reinterventions, limb salvage, survival, complications, and clinical improvement. Results: Between 2016 and 2020, 109 limbs in 103 patients were included. A total of 48 TASC II C and 61 TASC II D lesions with a mean lesion length of 264 mm were reported. In 53% of limbs, the indication for treatment was chronic limb-threatening ischemia. The median follow-up was 45 months. Technical success was achieved in 88% of cases, despite 23% of the lesions being longer than 30 cm (retrograde popliteal access in 22%). At four-year follow-up, primary patency, secondary patency, and freedom from target lesion revascularizations were 35%, 48%, and 58%, respectively. Limb salvage and survival were 90% and 80% at 4 years. Clinical improvement of at least one Rutherford category at the end of follow-up was achieved in 83% of limbs. Conclusions: This study reports the longest follow-up of endovascular treatment with nitinol stents in femoropopliteal TASC II C and D lesions. The results emphasize the feasibility of an endovascular-first strategy, even in lesions beyond 30 cm in length, and clarify its acceptable long-term durability and good clinical outcomes. Large multicenter RCTs with mid- and long-term follow-up are needed to investigate the role of different endovascular techniques in long femoropopliteal lesions.

State-of-the-Art Endovascular Therapies for the Femoropopliteal Segment: Are We There Yet?

Peripheral arterial disease is an increasingly prevalent condition with significant associated morbidity, mortality, and health care expenditure. Endovascular interventions are appropriate for most patients with either ongoing symptoms of intermittent claudication despite lifestyle and medical optimization or chronic limb-threatening ischemia. The femoropopliteal segment is the most common arterial culprit responsible for claudication and the most commonly revascularized segment. Endovascular approaches to revascularization of the femoropopliteal segment are advancing with an evolving landscape of techniques for arterial access, device-based therapies, vessel preparation, and intraprocedural imaging. These advances have been marked by debate and controversy, notably related to the safety of paclitaxel-based devices and necessity of atherectomy. In this review, we provide a critical overview of the current evidence, practice patterns, emerging evidence, and technological advances for endovascular intervention of the femoropopliteal arterial segment.

Intensive exercise therapy for restenosis after superficial femoral artery stenting: the REASON randomized clinical trial

Endovascular treatment (EVT) is the main treatment for peripheral artery disease (PAD). Despite advances in device development, the restenosis rate remains high in patients with femoropopliteal lesions (FP). This study aimed to evaluate the effectiveness of exercise training in reducing the 1-year in-stent restenosis rate of bare metal nitinol stents for FPs. This prospective, randomized, open-label, multicenter study was conducted from January 2017 to March 2019. We randomized 44 patients who had claudication with de novo stenosis or occlusion of the FP into an intensive exercise group (n = 22) and non-intensive exercise group (n = 22). Non-intensive exercise was defined as walking for less than 30 min per session, fewer than three times a week. We assessed exercise tolerance using an activity meter at 1, 3, 6, and 12 months, and physiotherapists ensured maintenance of exercise quality every month. The primary endpoint was instant restenosis defined as a peak systolic velocity ratio > 2.5 on duplex ultrasound imaging. Kaplan–Meier analysis was used to evaluate the data. There were no significant differences in background characteristics between the groups. Six patients dropped out of the study within 1 year. In terms of the primary endpoint, intensive exercise significantly improved the patency rate of bare nitinol stents at 12 months. The 1-year freedom from in-stent restenosis rates were 81.3% in the intensive exercise group and 47.6% in the non-intensive exercise group (p = 0.043). No cases of stent fracture were observed in the intensive exercise group. Intensive exercise is safe and reduces in-stent restenosis in FP lesions after endovascular therapy for PAD. Clinical trial registration: University Hospital Medical Information Network Clinical Trials Registry (No. UMIN 000025259).

Endovascular treatment of femoro-popliteal disease with the Supera stent: results of a multicenter study

Background: Even though many types of stents have been tested in superficial femoral artery (SFA) and popliteal artery (PA), most of these devices have provided an unsatisfactory outcome, probably due their unsuitable anatomical and physiological characteristics. The Supera peripheral stent (Abbott Vascular, Santa Rosa, CA, USA) is a braided interwoven nitinol device specifically designed for treating atherosclerotic lesions of the femoro-popliteal segment. The aim of this multicenter retrospective study was to describe the effectiveness of Supera stents in the management of femoral-popliteal atherosclerotic lesions and to critically analyze our findings in the context of current and past literature.

Design and methods: In this study we enrolled only patients who satisfied the inclusion criteria: i) patients affected by chronic obstructive arterial disease (COAD) grade II, as per Rutherford classification; ii) patients treated with endovascular revascularization and Supera stent implantation in the femoro-popliteal axis. We retrospectively analyzed the Doppler Ultra-sound (US) follow- up at 12-24 and 36 months to detect the vascular occlusions. The primary patency, primary patency assisted and TLR were described statistically analyzed by survival analysis and the demographic data, clinical data, device safety following stenting were described as frequency and mean value.

Results: 105 endovascular procedures on 99 patients for femoro-popliteal stenting with Supera were performed in four Italian hospitals. The median follow-up was 39 months (range 6-72), with primary patency rate of 83.1%, 74.3% and 69.5% at 12, 24 and 36 months after the procedure. The primary patency assisted was 89.9%, 76.8% and 73.4% in the same period, while the freedom from TLR values were 92.7%, 91.5% and 89.5% at 12, 24 and 36 months after the procedure, respectively. The mortality rate recorded at 12 months from the Supera implantation was 2.8% (3 out of 99 patients enrolled).

Conclusions: Our data were in agreement with the current literature, showing the non-inferiority Supera stent in relation to the other stent available. Supera stent showed an excellent safety, effectiveness profile and high durability for the treatment of PAD patients with femoro-popliteal artery disease.

Percutaneous Femoropopliteal Bypass: 2-Year Results of the DETOUR System

PURPOSE

This study investigated the 2-year safety and effectiveness of the PQ Bypass DETOUR system as a percutaneous femoropopliteal bypass.

MATERIALS AND METHODS

Seventy-eight patients with 82 long-segment femoropopliteal lesions were enrolled in this prospective, single-arm, multicenter study. The DETOUR system deployed Torus stent grafts directed through a transvenous route. Eligible patients included those with lesions of >10 cm and average of 371±55 mm. Key safety endpoints included major adverse events (MAEs) and symptomatic deep venous thrombosis in the target limb. Effectiveness endpoints included primary patency defined as freedom from ≥50% stenosis, occlusion, or clinically-driven target vessel revascularization (CD-TVR), primary assisted, and secondary patency.

RESULTS

Chronic total occlusions and severe calcium occurred in 96% and 67% of lesions, respectively. Core laboratory-assessed total lesion length averaged 371±51 mm with a mean occlusion length of 159±88 mm. The rates of technical and procedural success were 96%, with satisfactory delivery and deployment of the device without in-hospital MAEs in 79/82 limbs. The MAE rate was 22.0%, with 3 unrelated deaths (4%), 12 CD-TVRs (16%), and 1 major amputation (1%). Deep venous thrombosis developed in 2.8% of target limbs, and there were no reported pulmonary emboli. Primary, assisted primary, and secondary patency rates by the Kaplan-Meier analysis were 79±5%, 79±5%, and 86±4%, respectively.

CONCLUSIONS

The PQ Bypass DETOUR system is a safe and effective percutaneous alternative to femoropopliteal open bypass with favorable results through 2 years. The DETOUR system provides a durable alternative to conventional endovascular modalities and open surgery for patients with long, severely calcified, or occluded femoropopliteal lesions.

Comparison of Prosthetic and Vein Bypass with Nitinol Stents in Long Femoropopliteal Lesions

BACKGROUND

Guidelines for the treatment of long femoropopliteal lesions are not based on a high level of evidence and recent randomized controlled trials (RCTs) challenge vein bypass (VBP) as the recommended therapy. This study compared prosthetic (PTFE) bypass, VBP and angioplasty with nitinol stents in long femoropopliteal lesions.

METHODS

Pooled data from a RCT and a retrospective database with the same inclusion criteria were analyzed with primary and secondary patency as well as freedom from target lesion revascularization (TLR) as primary endpoints.

RESULTS

Between 2016 and 2018 a total of 172 lesions were treated in three groups (PTFE: n = 62, VBP: n = 55, stent: n = 55). Clinical and lesion characteristics were similar with mean lesion lengths between 260 and 279mm. Technical success rate in the stent group was 87%. There were no significant differences between the groups in patency rates, freedom from TLR, limb salvage and survival during 2-year follow-up. The primary patency rates for the PTFE, VBP and stent groups were 50%, 56% and 60% at 2 years. The PTFE group had significantly less complications compared to the other groups and a shorter hospital-stay compared to the VBP group. Clinical improvement was significantly better in the PTFE and VBP group compared to the stent group.

CONCLUSIONS

The 2-year results indicate that the role of VBP as the recommended therapy for long femoropopliteal lesions may not be unchallenged due to the similar results in all three groups. Further RCTs are needed to determine the best revascularization modality for long femoropopliteal lesions.

Predictive Factors for Restenosis Following Stent-Supported Endovascular Therapy with Intravascular Ultrasound Evaluation for Femoropopliteal Chronic Total Occlusion

PURPOSE

To determine the predictive factors for in-stent restenosis (ISR) following stent-supported endovascular therapy (EVT) with intravascular ultrasound (US) evaluation for femoropopliteal chronic total occlusion.

MATERIALS AND METHODS

This was a single-center, retrospective, observational study. The study included 276 lesions in 251 patients who underwent stent-supported EVT with intravascular ultrasound evaluation for femoropopliteal chronic total occlusion from July 2012 to June 2019. The wire passage route was assessed using intravascular US, and lesions were classified accordingly into 2 groups: intraluminal and subintimal passage. In this study, the intraluminal group was further divided into 3 subgroups by severity of calcification: none, <180°, and ≥180° circumferential. The subintimal group was further divided into 2 subgroups: subintimal passage without or with calcification. The primary outcome measure was ISR. Cox proportional hazards regression was used to determine the association of clinical characteristics with ISR rates.

RESULTS

The mean follow-up period was 19 months ±16, during which time ISR was observed in 31% of lesions. After multivariate analysis, an increased degree of plaque burden (hazard ratio [HR] = 1.101) and subintimal passage with calcification (HR = 3.408) were associated with an increased risk of ISR; a larger distal external elastic membrane area (HR = 0.898) and use of a stent graft (HR = 0.130) were significantly associated with a reduced risk of ISR.

CONCLUSIONS

This study revealed that factors associated with ISR after stent-supported EVT with intravascular US evaluation were distal external elastic membrane area, plaque burden, subintimal passage with calcification, and use of a stent graft.

Overview of the Virtual 2021 FDA's Circulatory System Devices Advisory Panel on Lutonix 014 Drug-Coated Percutaneous Transluminal Angioplasty Catheter for Below-the-Knee Lesions in Critical Limb Ischemia

Peripheral artery disease, along with subsequent critical limb ischemia (CLI), is highly prevalent, increases with age, and carries high morbidity and mortality. Specific devices for treatment of below-the-knee (BTK) lesions are limited. On February 17, 2021, the United States Food and Drug Administration convened a virtual meeting of the Circulatory System Devices Panel of the Medical Devices Advisory Committee to consider a premarket approval application for the Lutonix 014 Drug-Coated Balloon Percutaneous Transluminal Angioplasty Catheter (Becton, Dickinson and Company, Franklin Lakes, New Jersey) for the treatment of obstructive de novo or non-stented restenotic lesions in BTK vessels (popliteal, tibial, and peroneal arteries) in patients with CLI. We summarize the presentations and the panel deliberations, including voting outcome and recommendations for risk versus benefit.

A Budget Impact Model for the use of Drug-Eluting Stents in Patients with Symptomatic Lower-Limb Peripheral Arterial Disease: An Australian Perspective

Purpose

Improvement in long-term outcomes through innovative, cost-effective medical technologies is a focus for endovascular procedures aimed at treating symptomatic lower-limb peripheral arterial disease (PAD). The advent of drug-eluting stents (DES) has improved symptomatic PAD treatment via a reduction in high rates of target lesion revascularisation (TLR). The present study aimed to compare the 5-year financial impact of treatment with Eluvia, a new paclitaxel-eluting stent, versus treatment with Zilver PTX, a drug-coated stent, among patients in Australia by developing a budget impact model (BIM).

Methods

A BIM was developed from an Australian public hospital payer perspective using Australian national cost weights (AUD), published literature, and public hospital audit data. Clinical outcomes, including clinically driven TLRs (CD-TLRs), adverse events, and length of stay, were based on the 2-year results of the IMPERIAL trial, which compared Eluvia DES to Zilver PTX.

Results

Assuming EVP eligibility rate of 80% and DES uses rate ranging from 10 to 28% (superficial femoral artery lesions only), the 5-year model forecasted a treatment population between 14,428 and 40,399 patients. The model estimated 1499–4198 fewer CD-TLRs and 16,515–46,243 fewer hospital days with Eluvia DES use. This translated to 5-year potential savings of $4.3–$12.1 million to the Australian public hospital payer attributable to reduced CD-TLRs for Eluvia DES and $33.1–$92.6 million to Australian public hospitals owing to reduced adverse events and hospital bed days.

Conclusion

Eluvia DES use as treatment for symptomatic lower-limb PAD could lead to potential savings for the Australian public healthcare system based on improved patient outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00270-021-02848-8.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Long-term results of endovascular reconstruction for aortoiliac occlusive disease

Background

Open surgery is the gold standard for the treatment of aortoiliac occlusive disease (AIOD). Endovascular therapy has emerged as an attractive alternative for AIOD due to its minimal invasiveness. The aims of the present study were to investigate the long-term patency of endovascular treatment and to compare the outcomes of Transatlantic Inter-Society Consensus II (TASC II) A/B and C/D lesions.

Methods

Patients with AIOD (n=156) were enrolled in this retrospective cohort study. Patency rates were assessed at 12, 36, and 60 months after the procedure. Parameters for comparisons between TASC II A/B and C/D lesions included primary patency, secondary patency, freedom from target lesion revascularization (TLR), the technical success rate, the rate of complications, and risk factors for in-stent restenosis.

Results

For all patients, the technical success rate was 98.7%, the complication rate was 4.5%, and the mean follow-up period was 35.7 months. At 12, 36, and 60 months after the procedure, the primary patency rates were 96.5%, 88.3%, and 80.4%, respectively. The secondary patency rates were 99%, 96.4%, and 88%, respectively. The rates of freedom from TLR were 97.5%, 91.6%, and 89.6%. No significant differences were observed between A/B and C/D lesions in terms of primary patency (P=0.443), secondary patency (P=0.393), or freedom from TLR (P=0.481).

Conclusions

Endovascular reconstruction is effective and safe for AIOD, and should be the first-line treatment option for patients with TASC II A-D aortoiliac lesions.

Evaluation of the role of peripheral artery plaque geometry and composition on stent performance

Peripheral stent fracture is a major precursor to restenosis of femoral artery atherosclerosis that has been treated with stent implantation. In this work, we validate a workflow for performing in silico stenting on a patient specific peripheral artery with heterogeneous plaque structure. Six human cadaveric femoral arteries were imaged ex vivo using intravascular ultrasound virtual histology (IVUS-VH) to obtain baseline vessel geometry and plaque structure. The vessels were then stented and the imaging repeated to obtain the stented vessel lumen area. Finite element (FE) models were then constructed using the IVUS-VH images, where the material property constants for each finite element were calculated using the proportions of each plaque component in the element, as identified by the IVUS-VH images. A virtual stent was deployed in each FE model, and the model lumen area was calculated and compared to the experimental lumen area to validate the modeling approach. The model was then used to compare stent performance for heterogeneous and homogeneous artery models, to determine whether plaque geometry or composition had added effects on stent performance. We found that the simulated lumen areas were similar to the corresponding experimental values, despite using generic material constants. Additionally, the heterogeneous and homogeneous lumen areas were also similar, implying that plaque geometry is a stronger predictor of stent expansion performance than plaque composition. Comparing stent stress and strain for heterogeneous and homogeneous models, it was found that stress from these two models had a strong linear correlation, while the strain correlation was weaker but still present. This implies that stent performance may be predicted with a simple homogeneous material models accounting for overall geometry of the plaque, providing that stent fatigue is calculated using stress criteria.

Stents in the femoropopliteal territory: prevalence of fractures and their consequences

OBJECTIVE

Endovascular treatment for femoropopliteal arterial disease has made revascularization procedures less invasive, but the self-expanding stents used can suffer great wear in arteries with extreme mobility. To evaluate the prevalence of fractures in stents implanted in the femoropopliteal segment, to identify predisposing factors and consequences on arterial patency.

METHOD

between March and June 2019, thirty patients previously operated for femoropopliteal obstruction underwent stent X-rays in anteroposterior and lateral views to detect fractures and Doppler to analyze arterial patency.

RESULTS

we observed 12 cases with fractures (33.3%): 1 type I (2.8%), 3 type II (8.3%), 5 type III (13.9%), 3 type IV (8.3%) and no type V. According to the TASC II we had 1 in group B (8.3%), 6 in group C (50%) and 5 in group D (41.6%) p <0.004. The number of stents per limb was 3.1 (± 1.3) in cases of fracture versus 2.3 (± 1.3) in cases without fracture (p = 0.08). The extension was 274.17mm (± 100.94) in cases of fracture and 230.83mm (± 135.44) in cases without fracture (p = 0.29). On Doppler we had: 17 patients (47.2%) without stenosis, 9 patients (25%) with stenosis> 50% and 10 patients (27.8%) with occlusion (p = 0.37). There was no correlation between fracture and arterial obstruction (p = 0.33).

CONCLUSION

stent fractures are a frequent finding in the femoropopliteal area (33.3%), being more prevalent in cases of more advanced disease (C and D). There was no association between the finding of fracture and arterial obstruction.

Effect of conservative treatment in aortoiliac occlusive disease

Objective: To determine the effect of primary conservative treatment without revascularization in patients with proven aortoiliac occlusive disease (AIOD) presenting with intermittent claudication (IC).Background: The initial treatment of IC should focus on supervised exercise therapy (SET) and pharmacotherapy. Nowadays, primary endovascular revascularization (EVR) has become increasingly popular in patients with all types of AIOD. But in daily practice, EVR is often performed without initially extensive exercise.Method: This is a single centre retrospective study from December 2012 to September 2017. Primary outcomes were maximum walking distance (MWD) and patient satisfaction. Secondary outcomes were revascularization rate and mortality.Results: Twenty-four patients were included. Mean age was 64 years (SD: 9). Mean follow-up was 28 months (SD: 17). Nineteen patients (80%) had SET. In 18 (75%) patients, the MWD was improved compared to the initial situation. In five (21%) patients, the MWD stayed the same. The MWD of one (4%) patient decreased. Overall satisfaction rate was 87%. Three patients (13%) were not satisfied with the conservative treatment and eventually got an EVR. There was no disease related death.Conclusions: Conservative treatment, especially with SET, has acceptable subjective symptom outcomes in selected patients with AIOD. It could be a good alternative treatment for certain patients with AIOD and IC.

Novel diagnostic and imaging techniques in endovascular iliac artery procedures

INTRODUCTION

Endovascular revascularization has become the preferred treatment for most patients with iliac artery obstructions, with a high rate of clinical and technical success.

AREAS COVERED

This review will describe novel developments in the diagnosis and treatment of iliac artery obstructions including the augmentation of preprocedural imaging with advanced flow models, image fusion techniques, and state-of-the-art device-tracking capabilities.

EXPERT OPINION

The combination of these developments will change the endovascular field within the next 5 years, allowing targeted iliac treatment without the need for radiographic imaging or iodinated contrast media.

Nitinol Stent Versus Bypass in Long Femoropopliteal Lesions: 2-Year Results of a Randomized Controlled Trial

OBJECTIVES

This study sought to compare patency rates and clinical outcomes of nitinol stents and primary vein bypass in long femoropopliteal lesions.

BACKGROUND

An endovascular-first strategy for long femoropopliteal lesions is widely recommended without sufficient data comparing it with bypass surgery. Nitinol stents are widely used as the standard endovascular therapy.

METHODS

A single-center randomized controlled trial was performed with the primary endpoints of technical success, primary and secondary patency. Secondary endpoints were limb salvage, survival, complications, and clinical improvement.

RESULTS

A total of 110 limbs (55 per group) in 103 patients were treated. Baseline and lesion characteristics were similar, with a mean lesion length of 276 mm. Critical limb threatening ischemia was the indication for treatment in 49% of limbs in both groups. Technical success was achieved in 87% in the stent group. During a 2-year follow-up, patency rates, limb salvage, survival and complications showed no significant differences between both groups. At 24 months, primary and secondary patency rates for the stent group were 60% and 72% versus 56% and 73% in the bypass group, respectively. Clinical improvement was significantly better in the bypass group.

CONCLUSIONS

There were no significant differences regarding patency rates, limb salvage, survival, or complications after 2 years. Technical success and clinical improvement in the bypass group were significantly better, but the promising results of the stent group suggest that an endovascular-first strategy for femoropopliteal lesions up to 30 cm may be reasonable. Mid- as well as long-term results need to be awaited.

PTA and Stenting of Femoropopliteal Trunk With Cordis Smartflex Stent System: A Single-Center Experience

Introduction:

The aim of this study is to describe our experience in the treatment of femoropopliteal occlusive disease with percutaneous transluminal angioplasty (PTA) followed by stenting with S.M.A.R.T. Flex vascular stent system.

Materials and Methods:

From June 2014 to October 2018, 80 patients were treated at our Institution for intermittent claudication, critical, or acute limb ischemia due to total occlusion or long diffused lesions of the femoropopliteal segment. Main study end points are primary patency, target lesion revascularization, and stent fractures; secondary end points are major amputation rate, procedure-related bleeding, incidence of intrastent restenosis, and primary assisted patency after reintervention.

Results:

Mean follow-up time was 21 months (range 2-48 months). Primary patency rate was 80% (64 patients of 80), with mean covered lesion length of 8.2 cm. The deployment of a single stent was obtained for 57 (89%) patients, with a mean stent length of 9.86 cm. Of 80 patients, 2 (2.5%) had early stent occlusion within first 48 hours after the procedure, while 4 (5%) of 80 patients experienced stent occlusion within first 6 months. Of 80 patients, 6 (7.5%) had an intrastent restenosis detected at duplex ultrasound with a primary-assisted patency after simple re-PTA procedures of 83.3% at 12 months.

Discussion:

In the literature, primary patency after PTA and stenting of the femoropopliteal trunk seems to be related to several variables, such as number of stents used, specific stent length, diameters, type and length of lesions, type of pathology (if acute or chronic), and number of preoperatory patent below-the-knee vessels. In this study, we try to analyze each single factor in order to understand their role in predisposing specific stent restenosis.

Conclusions:

S.M.A.R.T. Flex vascular stent system has shown good results in terms of primary patency in the treatment of calcified lesions both at SFA and at popliteal level. However, in our experience, stent patency seems to be significantly poorer in patients presenting with acute limb ischemia associated with chronic atherosclerotic disease as well as for lesions located in the mid-distal part of the popliteal artery and both when number of stents increases or number of runoff vessel decreases.

Drug-Eluting Versus Bare-Metal Stent Implantation With or Without Cilostazol in the Treatment of the Superficial Femoral Artery

BACKGROUND

New-generation bare-metal nitinol (BNS) and drug-eluting stents have improved long-term outcomes in patients undergoing endovascular therapy for femoropopliteal lesions. Furthermore, cilostazol reduces in-stent restenosis (ISR) after first-generation BNS implantation for femoropopliteal lesions.

METHODS AND RESULTS

We studied 255 patients with femoropopliteal lesions treated at 25 cardiovascular centers. Patients were randomly assigned to the BNS group (Misago stent implantation without cilostazol), BNS with cilostazol group (Misago stent implantation with cilostazol), or drug-eluting stents group (Zilver PTX stent implantation without cilostazol). Primary end point was 1-year restenosis noted using duplex ultrasound (peak systolic velocity ratio, >2.0). Secondary end point was major adverse limb events (limb-related death, target lesion revascularization, major amputation, and major bleeding). During the 1-year follow-up, 12 patients (4.7%) died and 237 (92.9%) had relevant ultrasound findings. The 1-year ISR rate did not differ significantly among the BNS, BNS with cilostazol, and drug-eluting stents groups (28.4% versus 12.2% versus 21.0%; P=0.052). Although the 1-year ISR rate was significantly lower in the BNS with cilostazol group than in the BNS group, it was similar to that in the drug-eluting stents group ( P=0.16). Major adverse limb event was significantly higher in the BNS group (16.9% versus 6.5% versus 6.3%; P=0.034); however, target lesion revascularization and major bleeding were similar (9.7% versus 5.1% versus 3.6%; P=0.25, 4.8% versus 1.2% versus 2.4%; P=0.37, respectively).

CONCLUSIONS

Misago stent implantation with cilostazol showed a comparable 1-year ISR rate with Zilver PTX. Cilostazol reduced the 1-year ISR rate after endovascular therapy when used with new-generation BNS.

CLINICAL TRIAL REGISTRATION

URL: http://www.umin.ac.jp/ctr/ . Unique identifier: UMIN 000010071.

The current state of surgical bypass versus drug eluting stents for long femoropopliteal occlusive lesions

Considerable advances have been made over the last decade in the management of patients with peripheral artery disease. Historically, endovascular treatment has been the accepted approach for short lesions and surgical bypass for long, complex femoropopliteal lesions. However, bypass surgery holds significant risk of mortality and morbidity for the patient. That toll includes prolonged hospitalization, as well as the potential for wound healing and systemic complications, all of which are intensified by the ageing population. Advances in endovascular devices, such as drug eluting stents present an alternative, minimally invasive treatment option which may more suitable for complex lesions in a high-risk population. The aim of this review is to discuss the current literature which addresses surgical bypass and drug eluting stents, particularly for the treatment of long, complex femoropopliteal disease.

Drug-coated balloon versus plain old balloon angioplasty in femoropopliteal disease: An updated meta-analysis of randomized controlled trials

BACKGROUND

Drug-coated balloon (DCB) angioplasty has emerged as a mainstay of therapy for the treatment of peripheral arterial disease (PAD) involving the superficial femoral and popliteal arteries. We performed a meta-analysis including all available randomized controlled trials (RCTs) to date which compare DCB to plain balloon angioplasty (POBA) in femoropopliteal disease (FPD).

METHODS

Five databases were analyzed including EMBASE, PubMed, Cochrane, Scopus, and Web-of-Science from January 2000 to September 2018 for RCTs comparing DCB to POBA in patients with FPD. Heterogeneity was determined using Cochrane's Q-statistics. Random effects model was used.

RESULTS

Twenty-two RCTs, including five trials of in-stent restenosis (ISR) intervention, with 3,217 patients were included in the analysis. Mean follow-up was approximately 21.6 ± 14.4 months. Overall, DCB use was associated with a 51% reduction in target vessel revascularization (TLR) when compared to POBA at follow-up (relative risk [RR]: 0.49, 95% confidence interval [CI]: 0.40-0.61, P < 0.0001). Rates of TLR were 45% lower in the DCB group when compared to POBA in patients with ISR (RR: 0.55, 95% CI: 0.37-0.81, P = 0.002). DCB was associated with lower rates of binary stenosis, late lumen loss and higher primary safety endpoints. Major amputation and mortality were not different between DCB and POBA.

CONCLUSIONS

Use of DCBs is associated with improved vessel patency and a lower risk of TLR when compared to POBA in patients with FPD, especially in the setting of ISR. There was no difference in mortality between DCB and POBA in our meta-analysis. Extended follow-up of the available RCT data will be essential to analyze long-term device-related mortality.

Self-Expanding Nitinol Stent vs Percutaneous Transluminal Angioplasty in the Treatment of Femoropopliteal Lesions: 3-Year Data From the SM-01 Trial

Purpose: To report the midterm outcomes of a trial comparing self-expanding nitinol stents to percutaneous transluminal angioplasty (PTA) with provisional stenting in the treatment of obstructive disease in the superficial femoral and popliteal arteries. Materials and Methods: The SM-01 study ( ClinicalTrials.gov identifier NCT01183117), a single-blinded, multicenter, randomized controlled trial in Japan, enrolled 105 consecutive patients with de novo or postangioplasty restenotic femoropopliteal lesions; after removing protocol violations (1 from each group), 51 patients (mean age 74±8 years; 36 men) in the stent group and 52 patients (mean age 73±8 years; 35 men) in the PTA group were included in the intention-to-treat analysis. The groups were well-matched at baseline. Patients were followed to 36 months with duplex imaging. Three-year primary patency was assessed based on a duplex-derived peak systolic velocity ratio <2.5. Freedom from clinically-driven target vessel revascularization (TVR) and target lesions revascularization (TLR) were estimated using the Kaplan-Meier method. Results: The technical success rate was higher (100% vs 48%, p<0.001) and the frequency of vascular dissection was lower (4% vs 31%, p<0.001) in the stent group. The S.M.A.R.T stent group had a higher 3-year primary patency rate (73% vs 51%, p=0.033). Freedom from clinically-driven TVR and TLR were not significantly different between the groups. Conclusion: The S.M.A.R.T. stent maintained a higher primary patency rate than PTA at 3 years in this randomized trial; the need for clinically-driven revascularization was similar for both therapies.

Management of isolated femoropopliteal in-stent restenosis

OBJECTIVE

The optimal catheter-directed therapy for femoropopliteal in-stent restenosis (ISR) remains controversial with limited durability. The natural history of untreated ISR is not well characterized. We evaluated the midterm outcomes of patients with asymptomatic isolated femoropopliteal ISR who were observed under a surveillance program.

METHODS

Patients treated with isolated femoropopliteal stents from January 2009 to December 2013 were retrospectively investigated for the development of ISR. ISR was classified on the basis of duplex ultrasound criteria, with >50% defined as peak systolic velocity (PSV) twice that of the normal vessel and >75% as PSV >400 cm/s or four times the normal PSV. Asymptomatic patients with ISR of >50% were tracked for progression to high-grade (>75%) stenosis, occlusion, need for reintervention, and amputation.

RESULTS

Asymptomatic ISR of >50% was identified in 62 (15.3%) of 402 patients with isolated femoropopliteal stents. The mean time for development of ISR was 22.1 (±20.1) months. The mean age was 72 (±9.7) years, and 34 (55.7%) patients were female. Thirty-one (50%) patients were diabetic, 18 (29.1%) were smokers, and 8 (12.9%) had chronic kidney disease. Indications for treatment were claudication in 49 (79.0%), tissue loss in 9 (14.5%), and rest pain in 4 (6.4%) patients. TransAtlantic Inter-Society Consensus (TASC) A lesions were treated in 13 (21%) patients, TASC B lesions in 24 (38.7%), and TASC C lesions in 25 (40.3%). Three-vessel runoff was identified in 25 (40.3%) patients, two-vessel runoff in 18 (29.0%), and one-vessel runoff in 19 (30.6%). Under surveillance, ISR of >50% progressed to >75% or occlusion in 20 (32.3%) patients. The mean time to progression was 17.4 months, and the mean overall follow-up was 33.1 months. Reintervention was required in 22 (35.0%) patients, with an average of 1.95 (range, 1-4) interventions per patient. Reintervention was undertaken in 19 (86%) patients for claudication and in 3 (18%) patients for critical limb ischemia. One patient required an amputation despite previous reintervention for progression. Progression to >75% stenosis was predictive of need for reintervention (P = .004).

CONCLUSIONS

Under a surveillance program, asymptomatic patients with femoropopliteal ISR of >50% may be observed with a low risk of limb loss. Given the slow rate of progression and the poor durability of reintervention, surveillance with delayed intervention may be warranted.

Impact of Tibial Runoff on Outcomes of Endovascular Treatment for Femoropopliteal Atherosclerotic Lesions

Objectives:

The aim of this study is to investigate the impact of tibial runoff on outcomes of femoropopliteal interventions for atherosclerotic lesions.

Methods:

A retrospective review of 243 endovascular procedures for femoropopliteal atherosclerotic lesions on 243 limbs of 197 patients was performed.

Results:

The distribution rates of good tibial runoff (runoff score <7) and poor tibial runoff (runoff score ≥7) were 37.0% and 63.0%, respectively. In the poor tibial runoff group, the patients were older ( P = .019), and the proportion of male was lower ( P = .014). There was a significantly higher proportion of rest pain or tissue loss ( P < .001), and the prevalence of stroke ( P = .031) and renal insufficiency ( P = .005) was significantly higher in the poor runoff group. After femoropopliteal intervention, the amputation-free survival ( P = .03) and freedom from ischemia ( P = .003) were significantly lower in the poor runoff group. The interventions targeting below-the-knee (BTK) lesions performed concomitantly for critical limb ischemia or tissue loss with poor tibial runoff did not show a significant advantage in terms of freedom from ischemia; however, minor trends of longer lasting freedom from ischemia were observed when BTK intervention was combined.

Conclusion:

The patients with poor runoff showed significantly lower amputation-free survival and freedom from ischemia. In poor tibial runoff limbs with critical limb ischemia or tissue loss, BTK intervention did not demonstrate additional significant beneficial outcomes; however, there was a minor trend of longer lasting freedom from ischemia after concomitant BTK intervention.

A case complicated by floating fractured stent 141 months after nitinol stent implantation in the superficial femoral artery

An 80-year-old man received the implantation of a self-expanding stent (Luminexx, Bard, Inc., Murray Hill, NJ, USA) for an in-stent restenosis (ISR) lesion in the superficial femoral artery. However, angiography 141 months after the Luminexx stent implantation showed 90% ISR and a floating fractured stent in the Luminexx site. Furthermore, the floating fractured stent strut itself was completely separated and flowed toward the posterior tibial artery. The stent strut was removed by a catheter for removing intravascular foreign substances. <Learning objective: We report a case of a floating fractured stent 141 months after stent implantation in the superficial femoral artery (SFA). Although this case is rare, in endovascular therapy with stenting for SFA, it is necessary to consider the risk of stent fracture in the very late phase.>.

The Lutonix® drug-coated balloon: A novel drug delivery technology for the treatment of vascular disease

Local drug delivery of an anti-proliferative drug from balloon catheter systems to the site of arterial injury has been attempted repeatedly over the years with limited success in drug uptake and retention. Accessibility of the drug at the site is critical to combat the body's response to the procedural trauma of angioplasty. Recently, formulations have been designed which achieve delivery of therapeutic doses of the anti-proliferative drug paclitaxel to arteries with higher efficiency and longer tissue retention. These formulations succeed through formation of a drug reservoir in the artery wall enabling release after the initial angioplasty procedure. These formulations have become the cornerstone of several drug coated balloon (DCB) technologies which have found an initial, broad therapeutic application in the treatment of stenosis of the superficial femoral artery (SFA). DCBs achieve drug delivery while leaving no implant behind and represent a new class of combination products developed at the interface of engineering, chemistry and medical science. This review article summarizes the development of the LUTONIX® drug coated balloon catheter. The introduction of DCB technology has provided clinicians and patients with new SFA treatment options while ongoing clinical evidence in additional vascular beds is generated.

[Subintimal recanalization. Indications, technique and results]

CLINICAL/METHODICAL ISSUE

This article gives an overview of the current importance of so-called subintimal recanalization in the lower extremities.

STANDARD RADIOLOGICAL METHODS

The primary technical goal of endovascular interventions in the lower extremities is the endoluminal restoration of blood circulation from the iliac arteries into the feet.

METHODICAL INNOVATIONS

If endoluminal recanalization of e.g. high-grade flow-relevant stenoses or chronic total occlusion (CTO) is technically not possible, subintimal recanalization is a promising option and the only remaining minimally invasive alternative. During subintimal recanalization a channel is intentionally generated in the vessel wall (dissection) in order to bypass e. g. a chronic vascular occlusion over as short a distance as possible.

PERFORMANCE

The technical success rate for subintimal recanalization of CTO of the lower extremities is 65-100 %. Technical failure occurs in approximately 25 % using the catheter and wire technique and is caused in most cases by difficulties in reaching the true lumen after the subintimal passage (the so-called re-entry).

ACHIEVEMENTS

Compared to conventional subintimal recanalization, in recent years so-called re-entry devices have expanded the technical possibilities and depending on the medical experience and training level of the physician, provide an improvement in the technical success rate, a lower complication rate, a reduction of fluoroscopy time and the amount of necessary contrast medium but also result in higher costs.

PRACTICAL RECOMMENDATIONS

Subintimal recanalization, whether carried out conventionally with a catheter and wire or using re-entry devices, of high-grade stenoses or CTO in the lower extremities provides a high technical success rate but requires an experienced and trained physician who is capable of operating the elaborate materials and mastering any possible complications.

High dose-rate brachytherapy for the treatment of lower extremity in-stent restenosis

OBJECTIVE

Historically, edge stenosis and late thrombosis limited the effectiveness of adjunctive endovascular brachytherapy (EVBT) for in-stent restenosis (ISR) after percutaneous transluminal angioplasty (PTA) and stenting. We evaluated an updated protocol of PTA and EVBT for ISR among patients with lower extremity occlusive disease.

METHODS

This is a retrospective, single-center review of patients treated with PTA and EVBT for ISR in the iliac and femoropopliteal segments between 2004 and 2012. A dose of 20 Gy was given at a depth of 0.5 mm beyond the radius of the largest PTA balloon using iridium 192, with at least 2-cm-long margins of radiation coverage proximal and distal to the injured area. Stents were assessed for patency by duplex ultrasound imaging at 1, 3, 6, 9, 12, and 18 months and then yearly. The primary end point was freedom from ≥50% restenosis in the treated segment at 6 months, 1 year, and 2 years. Patency data were estimated using the Kaplan-Meier method. Secondary end points were early and late thrombotic occlusion.

RESULTS

Among 42 consecutive cases in 35 patients of EVBT for ISR in common or external iliac (9 [20.8%]) and superficial femoral or popliteal (33 [76.7%]) arteries, or both, 21 patients (50%) had claudication, asymptomatic hemodynamically significant stenoses were identified on duplex ultrasound imaging in 16 (38.1%), and 4 (9.8%) had critical limb ischemia. Mean treated length was 23.5 ± 12.3 cm over a mean duration of 16.1 ± 9.6 minutes. There was one technical failure (2.3%). Median post-EVBT follow-up time was 682 days (range, 1-2262 days). There were two (4.9%) and five (11.9%) cases of early and late thrombotic occlusions, respectively. There was one death, believed to be secondary to acute coronary syndrome. Primary, assisted primary, and secondary patency in the entire cohort was 75.2%, 89.1%, and 89.1%, respectively, at 1 year and 63.7%, 80.6%, and 85.6%, respectively, at 2 years.

CONCLUSIONS

This contemporary protocol of PTA and adjunctive EVBT for lower extremity ISR, which is updated from those used in prior trials and includes a surveillance strategy that identifies at-risk stents for reintervention before occlusion, may be a promising treatment for lower extremity ISR at institutions where a close collaboration between vascular surgeons and radiation oncologists is feasible.

Comparable 2-Year Restenosis Rates Following Subintimal and Intraluminal Drug-Eluting Stent Implantation for Femoropopliteal Chronic Total Occlusion

Purpose: To report midterm outcomes after subintimal vs intraluminal drug-eluting stent (DES) implantation for femoropopliteal (FP) chronic total occlusion (CTO). Methods: This subanalysis of the prospective, multicenter ZEPHYR study (ZilvEr PTX for tHe Femoral ArterY and Proximal Popliteal ArteRy) included 176 patients (mean age 74±8 years; 130 men) with 192 de novo FP CTOs that were evaluated by intravascular ultrasound after successful guidewire crossing. The primary outcome was the 2-year restenosis rate after subintimal (n=73) or intraluminal (n=119) DES implantation. Propensity score matching extracted 61 matched pairs (mean age 75 years; 49 men) for patency analysis to minimize baseline intergroup differences. Restenosis rates are reported with the 95% confidence interval (CI). Results: The 1-year restenosis rates in the groups with subintimal and intraluminal DES implantation were 45% (95% CI 32% to 59%) and 35% (95% CI 22% to 49%), respectively (p=0.352), whereas the corresponding rates at 2 years were not significantly different (p=0.648) at 56% (95% CI 41% to 71%) and 51% (95% CI 34% to 68%). Baseline characteristics had no significant interaction effect on the association of subintimal angioplasty with restenosis risk. Conclusion: In FP CTO, 2-year restenosis rates were comparable after subintimal or intraluminal DES implantation.

Morbidity of femoropopliteal bypass surgery

A systemic review of published reports on the incidence of early (<30 days) adverse events occurring after above- or below-knee femoropopliteal bypass surgery was conducted to provide contemporary outcomes data for comparative reporting. A total of 38 articles were included describing 6,374 femoropopliteal bypasses in 6,007 patients. Fifty-two percent were male and the mean age was 64.6 years (range, 40 to 93 years). The various studied types of complications were reported in 10 to 34 of 38 articles and definitions were often missing. The overall 30-day morbidity rate was 36.8%. The wound infection rate was 7.8% (range, 0.0 to 17.4%) accompanied with dermal necrosis in 0.4%. Graft infection was described in 2.4% (range, 0.0 to 5.3%) of cases. Postoperative bleeding was seen in 7.4% (range, 0.0 to 26%), of which 2.5% required return to surgery. Occlusions were reported in 12.0% (range, 0.0 to 59%). Lymphedema occurred in 2.9% (range, 0.0 to 9.6%) of cases and surgical site seroma formation occurred in 2.0% (range, 1.0% to 3.0%). Overall 30-day mortality rate was 2.3% (range 0.0 to 4.3%). Pooled data comparing vein grafts and prosthetic grafts revealed no significant difference (P = .10; risk ratio = 0.82; 95% confidence interval, 0.66-1.03; I(2) = 0%) in the incidence of complications. This review confirmed the morbidity of femoropopliteal bypass surgery is inconsistently reported and definitions are lacking. Because one-third of patients can be expected to experience an adverse event after femoropopliteal bypass grafting, standards on defining and reporting complications are necessary if comparative outcome standards are developed.