Zilver PTX Post-Market Surveillance Study of Paclitaxel-Eluting Stents for Treating Femoropopliteal Artery Disease in Japan: 12-Month Results

Clinical Comparison of Drug-Coated Balloon and Drug-Eluting Stent for Femoropopliteal Lesions in Chronic Limb-Threatening Ischemia With Wounds

BACKGROUND

Endovascular therapy (EVT) with devices such as drug-coated balloons (DCBs) and drug-eluting stents (DESs) for atherosclerotic disease in the femoropopliteal (FP) artery has been established. However, EVT using drug-based devices for chronic limb-threatening ischemia (CLTI) remains challenging. The optimal device for FP lesions in patients with CLTI remains unknown. This study compared the clinical efficacy of DCB and DES in patients with CLTI and FP lesions.

METHODS AND RESULTS

This retrospective single-center study included 539 consecutive patients (562 lesions) treated with EVT between January 2018 and December 2022; 166 patients with CLTI and Rutherford Class 5 or 6 wounds underwent EVT with DCB or DES. Clinical outcomes were compared between 53 pairs after propensity score matching. There were no significant differences between the DCB and DES groups in the incidence of complete wound healing without death or major amputation (84.8% vs. 80.2%, respectively; P=0.99), primary patency (69.4% vs. 75.6%, respectively; P=0.65), and freedom from target lesion revascularization at 1 year (78.6% vs. 78.0%, respectively; P=0.92). Multivariate analysis showed that complete wound healing at 1 year is negatively associated with hemodialysis and Wound, Ischemia, and foot Infection Stage 4, but positively associated with Global Limb Anatomic Staging System FP Grade 3 or 4.

CONCLUSIONS

No significant differences in clinical outcomes were found between DCB and DES for patients with CLTI and FP lesions.

Drug-eluting devices for lower limb peripheral arterial disease

Peripheral arterial disease is the third leading cause of cardiovascular morbidity after coronary artery disease and stroke. Lower limb peripheral arterial disease commonly involves infrainguinal arteries, may impair walking ability (intermittent claudication) and may confer a significant risk of limb loss (chronic limb-threatening ischaemia), depending on the severity of ischaemia. Endovascular treatment has become the mainstay revascularisation option in both the femoropopliteal and the below-the-knee arterial segments. After crossing and preparing the lesion, treatment results in these arterial segments can be enhanced by using drug-coated devices (drug-eluting stents and drug-coated balloons) that mitigate the occurrence of restenosis. As for other medical devices, the use of drug-eluting devices is based on their demonstrated safety and efficacy profiles when applied in the distinct segments of the lower limb vasculature. In this state-of-the-art narrative review we provide an overview of the safety and efficacy of drug-coated devices when used in the femoropopliteal and below-the-knee arterial segments.

Consensus minimum core data elements adapted to peripheral vascular intervention in the drug-eluting era: Consensus report from the Registry Assessment of Peripheral Interventional Devices (RAPID) Pathways "LEAN" working group

Registry Assessment of Peripheral Interventional Devices (RAPID) initiated the Pathways Program to provide a transparent, collaborative forum in which to pursue insights into multiple unresolved questions on benefit-risk of paclitaxel-coated devices, including understanding the basis of the mortality signal, without a demonstrable potential biological mechanism, and whether the late mortality signal could be artifact intrinsic to multiple independent prospective randomized data sources that did not prespecify death as a long-term end point. In response to the directive, the LEAN-Case Report Form working group focused on enhancements to the RAPID Phase I Minimum Core Data set through the addition of key clinical modifiers that would be more strongly linked to longer-term mortality outcomes after peripheral arterial disease intervention in the drug-eluting device era, with the goal to have future mortality signals more accurately examined.

ZILVERPASS Study: ZILVER PTX Stent versus Prosthetic Above-the-Knee Bypass Surgery in Femoropopliteal Lesions, 5-year Results

PURPOSE

To report the 60-month safety and effectiveness results of a multicenter, prospective, randomized controlled trial comparing the ZILVER PTX paclitaxel-eluting stent to prosthetic above-the-knee bypass for the treatment of symptomatic TransAtlantic Inter-Society Consensus (TASC) C and D femoropopliteal lesions.

MATERIALS AND METHODS

Patients were enrolled between October 2013 and July 2017. One of the secondary outcomes was primary patency at 60 months, defined as no evidence of binary restenosis or occlusion within the target lesion or bypass graft based on a duplex ultrasound peak systolic velocity ratio < 2.4 and no clinically-driven target lesion revascularization (TLR) in endovascular cases or reintervention to restore flow in the bypass at 60 months. Survival rates after 5 years were also analyzed.

RESULTS

220 patients (mean age 68.6 ± 10.5 years; 159 men) were included and randomized to ZILVER PTX (n = 113, 51.40%) or BYPASS group (n = 107, 48.60%). The 60-month primary patency rate was 49.3% for the ZILVER PTX group versus 40.7% for the bypass group (p = 0.6915). Freedom from TLR was 63.8% for the ZILVER PTX group versus 52.8% for the bypass group (p = 0.2637). At 5 years, no significant difference in survival rate could be seen between the ZILVER PTX and the bypass group (69.1% vs. 71% respectively, p = 0.5503).

CONCLUSION

Even at 5 years, non-inferior safety and effectiveness results of the ZILVER PTX could be seen. These findings confirmed that the use of ZILVER PTX stents can be considered as a valid alternative for bypass surgery when treating long and complex femoropopliteal lesions.

Long-Term Patient Outcomes After Femoropopliteal Peripheral Vascular Intervention in Patients With Intermittent Claudication

BACKGROUND

In patients with intermittent claudication (IC), short-term amputation rates from clinical trial data following lower extremity femoropopliteal (FP) peripheral vascular intervention (PVI) are <1% with unknown longer-term rates.

OBJECTIVES

The aim of this study was to identify revascularization and amputation rates following PVI in the FP segment and to assess 4-year amputation and revascularization rates after FP PVI for IC.

METHODS

From 2016 to 2020, 19,324 patients undergoing FP PVI for IC were included from the PINC AI Healthcare Database and evaluated by treatment level (superficial femoral artery [SFA], popliteal artery [POP], or both). The primary outcome was index limb amputation (ILA) assessed by Kaplan-Meier estimate. The secondary outcomes were index limb major amputation and repeat revascularization. HRs were estimated using Cox proportional hazard regression.

RESULTS

The 4-year index limb amputation rate following FP PVI was 4.3% (95% CI: 4.0-4.7), with a major amputation rate of 3.2% (95% CI: 2.9-3.5). After POP PVI, ILA was significantly higher than SFA alone (7.5% vs 3.4%) or both segment PVI (5.5%). In multivariate analysis, POP PVI was associated with higher ILA rates at 4 years compared with isolated SFA PVI (HR: 2.10; 95% CI: 1.52-2.91) and index limb major amputation (HR: 1.98; 95% CI: 1.32-2.95). Repeat FP revascularization rates were 15.2%; they were highest in patients undergoing both SFA and POP PVI (18.7%; P < 0.0001) compared with SFA (13.9%) and POP (17.1%) only.

CONCLUSIONS

IC patients undergoing FP PVI had 4-year rates of index limb repeat revascularization of 16.7% and ILA rates of 4.3%. Further risk factors for amputation requires further investigation.

One Year Outcomes of Zilver PTX Versus Eluvia for Femoropopliteal Disease in Real-World Practice: REALDES Study

PURPOSE

This multicenter, prospective, observational study aimed to compare Zilver PTX and Eluvia stents in real-world settings for treating femoropopliteal lesions as the differences in the 1-year outcomes of these stents have not been elucidated.

MATERIALS AND METHODS

Overall, 200 limbs with native femoropopliteal artery disease were treated with Zilver PTX (96 limbs) or Eluvia (104 limbs) at 8 Japanese hospitals between February 2019 and September 2020. The primary outcome measure of this study was primary patency at 12 months, defined as a peak systolic velocity ratio of ≤2.4, without clinically-driven target lesion revascularization (TLR) or stenosis ≤50% based on angiographic findings.

RESULTS

The baseline clinical and lesion characteristics of Zilver PTX and Eluvia groups were roughly comparable (of all limbs analyzed, approximately 30% presented with critical limb-threatening ischemia, approximately 60% presented with Trans-Atlantic Inter-Society Consensus II C-D, and approximately half had total occlusion), except for the longer lesion lengths in the Zilver PTX group (185.7±92.0 mm vs 160.0±98.5 mm, p=0.030). The Kaplan-Meier estimates of primary patency at 12 months were 84.9% and 88.1% for Zilver PTX and Eluvia, respectively (log-rank p=0.417). Freedom from clinically-driven TLR rates were 88.8% and 90.9% for Zilver PTX and Eluvia, respectively (log-rank p=0.812).

CONCLUSIONS

The results of the Zilver PTX and Eluvia stents were not different regarding primary patency and freedom from clinically-driven TLR at 12 months after treating patients with femoropopliteal peripheral artery disease in real-world settings.

CLINICAL IMPACT

This is the first study to reveal that the Zilver PTX and Eluvia have similar results in real-world practice when the proper vessel preparation is performed. However, the type of restenosis in the Eluvia stent may differ from that in the Zilver PTX stent. Therefore, the results of this study may influence the selection of DES for femoropopliteal lesions in routine clinical practice.

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.

First peripheral drug-eluting stent clinical results from China: 1-year outcomes of the Zilver PTX China study

Purpose

The benefit of using the Zilver PTX drug-eluting stent (DES) in superficial femoral artery (SFA) lesions has been demonstrated in multiple clinical studies. This prospective, multicenter study evaluated the 1-year safety and effectiveness of the DES for the treatment of femoropopliteal lesions in a Chinese patient population.

Methods

Patients with a single de novo or restenotic SFA lesion ≤140 mm and a Rutherford classification of 2 to 4 were treated with the DES. The primary endpoint was primary patency assessed by duplex ultrasound at 1-year. Secondary endpoints included adverse events, event-free survival (EFS), and freedom from target lesion revascularization (TLR). Clinical outcomes included Rutherford classification, ankle-brachial index (ABI), and the walking impairment questionnaire (WIQ).

Results

In this study, 178 patients with symptomatic peripheral artery disease were enrolled at nine institutions in China. The average lesion length was 79.0 ± 48.6 mm (range 14.8–245.4 mm) and 50.0% of lesions were total occlusions. The 1-year primary patency rate was 81.9%. Covariate analysis revealed that lesion length (p < 0.01) was the only significant factor for patency. No paclitaxel-related adverse events or amputations were reported. The 1-year rate for EFS was 94.9% and freedom from TLR was 95.5%. Through 1-year, treatment with the DES resulted in statistically significant improvement in ABI and WIQ scores compared with pre-procedure (p < 0.001). Clinical improvement of at least 1 Rutherford class was achieved in 142 of 174 patients (81.6%).

Conclusion

This study showed promising short-term results for the treatment of SFA lesions with Zilver PTX DES in Chinese patients.

Unique identifier

ClinicalTrials.gov, identifier: NCT02171962.

Catheter based interventions for lower extremity peripheral artery disease

The field of peripheral arterial intervention has exploded over the past 20 years. Current knowledge includes a growing evidence base for treatment as well as a myriad of new interventional approaches to complex disease. This review seeks to outline the current state of the art for interventional approaches to lower extremity peripheral arterial disease.

Outcomes of the paclitaxel-eluting Eluvia stent for long femoropopliteal lesions in Asian patients with predominantly chronic limb-threatening ischemia

The fluoropolymer-coated, paclitaxel-eluting Eluvia stent has shown promising results for the endovascular treatment of femoropopliteal artery lesions in patients with claudication. The aim of the current study was to evaluate efficacy and safety outcomes of the Eluvia stent for the treatment of long femoropopliteal lesions in Asian patients. This is a single-center, retrospective study. The primary endpoint was primary patency at 1 year. Secondary outcomes were 30-days complication rate, technical success, 1-year freedom from clinically driven target lesion revascularization (CD-TLR), limb salvage, survival, amputation-free survival (AFS), wound healing, and clinical improvement. A total of 64 patients with 67 femoropopliteal lesions were included; 78% suffered from diabetes and 84% had chronic limb-threatening ischemia (CLTI). Of those with ischemic wounds, 79% did not have run-off to the foot. Mean lesion length was 193 ± 128 mm and 52% were severely calcified. Primary patency at 1 year was 84% in the overall cohort and 91% in patients with complete lesion coverage with the Eluvia stent. Technical success was achieved in 100% of the cases and 30-day complications occurred in six patients. Twelve-month freedom from CD-TLR, limb salvage, survival, and AFS were 92%, 93%, 85%, and 80%, respectively. In 80% of patients, complete wound healing was experienced and 84% had clinical improvement after 1 year. The Eluvia stent showed promising 12-month patency and clinical results for femoropopliteal treatment in this CLTI-dominant patient population with severely calcified, long lesions. Patient numbers were, however, small; larger trials are required to validate these findings. Aneurysmal change seen in some cases also needs further investigation.

Important considerations for trials for peripheral arterial disease: Lessons learned from the paclitaxel mortality signal: A report on behalf of the registry assessment for peripheral interventional Devices (RAPID) Paclitaxel Pathways Program

The Registry Assessment of Peripheral Devices (RAPID) convened a multidisciplinary group of stakeholders including clinicians, academicians, regulators and industry representatives to conduct an in-depth review of limitations associated with the data available to assess the paclitaxel mortality signal. Available studies were evaluated to identify strengths and limitations in the study design and data quality, which were translated to lessons learned to help guide the design, execution, and analyses of future studies. We suggest numerous actionable responses, such as the development and use of harmonized data points and outcomes in a consensus lean case report form. We advocate for reduction in missing data and efficient means for accrual of larger sample sizes in Peripheral arterial disease studies or use of supplemental datasets. Efforts to share lessons learned and working collaboratively to address such issues may improve future data in this device area and ultimately benefit patients. Condensed Abstract: Data sources evaluating paclitaxel-coated devices were evaluated to identify strengths and limitations in the study design and data quality, which were translated to lessons learned to help guide the design, execution, and analyses of future studies. We suggest numerous actionable responses, which we believe may improve future data in this device area and ultimately benefit patients.

Long-Term Effectiveness of a Drug-Eluting Stent for Femoropopliteal In-Stent Restenosis: Subanalysis of the Zilver PTX Japan Post-Market Surveillance Study

PURPOSE

To present a subgroup analysis of patients from a large real-world study evaluating the safety and effectiveness of the Zilver PTX drug-eluting stent (DES) for treating femoropopliteal in-stent restenosis (ISR).

MATERIALS AND METHODS

This study examined patients enrolled in the Zilver PTX Japan Post-Market Surveillance Study (ClinicalTrials.gov identifier NCT02254837), a prospective, multicenter registry of 904 symptomatic patients with 1082 femoropopliteal lesions treated with the DES at 95 institutions in Japan. Five-year outcomes, including mortality, stent radiography, freedom from target lesion revascularization (TLR), and clinical benefit, were evaluated for 177 patients (mean age 74.2±8.3 years; 118 men) with 204 ISR lesions treated with the Zilver DES. Over half of the patients (108, 61.0%) were diabetic. Mean lesion length was 17.8±10.4 cm, and a third (72, 35.3%) were total occlusions. Outcome measures were all-cause mortality, thrombosis, freedom from TLR, and clinical benefit, defined as freedom from persistent or deteriorating ischemic symptoms.

RESULTS

No device-related or procedure-related deaths or paclitaxel-related adverse events were reported. All-cause mortality was 25.1% at 5 years. Stent fracture was observed in 5 stents through 5 years. The 5-year rate of freedom from clinically-driven TLR was 73.4%, and the rate of clinical benefit was 63.6%. Improvement in Rutherford category and ankle-brachial index was sustained through 5 years.

CONCLUSION

The safety and effectiveness of the Zilver PTX stent for the treatment of femoropopliteal ISR lesions demonstrated that this device provides a favorable treatment option in this difficult-to-treat subgroup.

Prediction Model for Freedom from TLR from a Multi-study Analysis of Long-Term Results with the Zilver PTX Drug-Eluting Peripheral Stent

Purpose

Develop a prediction model to determine the impact of patient and lesion factors on freedom from target lesion revascularization (ffTLR) for patients who are candidates for Zilver PTX drug-eluting stent (DES) treatment for femoropopliteal lesions.

Methods

Patient factors, lesion characteristics, and TLR results from five global studies were utilized for model development. Factors potentially associated with TLR (sex, age, diabetes, hypertension, hypercholesterolemia, renal disease, smoking status, Rutherford classification, lesion length, reference vessel diameter (RVD), popliteal involvement, total occlusion, calcification severity, prior interventions, and number of runoff vessels) were analyzed in a Cox proportional hazards model. Probability of ffTLR was generated for three example patient profiles via combinations of patient and lesion factors. TLR was defined as reintervention performed for ≥ 50% diameter stenosis after recurrent clinical symptoms.

Results

The model used records from 2227 patients. The median follow-up time was 23.9 months (range: 0.03–60.8). The Kaplan–Meier estimates for ffTLR were 90.5% through 1 year and 75.2% through 5 years. In a multivariate analysis, sex, age, Rutherford classification, lesion length, RVD, total occlusion, and prior interventions were significant factors. The example patient profiles have predicted 1-year ffTLRs of 97.4, 92.3, and 86.0% and 5-year predicted ffTLRs of 92.8, 79.5, and 64.8%. The prediction model is available as an interactive web-based tool (https://cooksfa.z13.web.core.windows.net).

Conclusions

This is the first prediction model that uses an extensive dataset to determine the impact of patient and lesion factors on ffTLR through 5 years and provides an interactive web-based tool for expected patient outcomes with the Zilver PTX DES.

Clinical Trial Registrations

Zilver PTX RCT unique identifier: NCT00120406; Zilver PTX single-arm study unique identifier: NCT01094678; Zilver PTX China study unique identifier: NCT02171962; Zilver PTX US post-approval study unique identifier: NCT01901289; Zilver PTX Japan post-market surveillance study unique identifier: NCT02254837.

Levels of Evidence

Zilver PTX RCT: Level 2, randomized controlled trial; Single-arm study: Level 4, large case series; China study: Level 4, case series; US post-approval study: Level 4, case series Japan PMS study: Level 4, large case series.

Electronic supplementary material

The online version of this article (10.1007/s00270-020-02648-6) contains supplementary material, which is available to authorized users.

Influence of Self-Expanding Paclitaxel-Eluting Stent Sizing on Neointimal Hyperplasia in Superficial Femoral Artery Lesions

BACKGROUND

Although self-expanding drug-eluting stents (DES) have recently shown superior outcomes for superficial femoral artery (SFA) lesions, optimal sizing of DES diameter in SFA intervention is unclear.Methods and Results:A total of 40 de novo SFA lesions were randomized 1:1 to receive self-expanding DES with either a 1-mm or 2-mm larger diameter than the reference vessel diameter. Follow-up optical coherence tomography (OCT) was scheduled 6 months after DES implantation to evaluate the vascular response to the stents. Volume index (VI) was defined as volume divided by stent length. The primary endpoint was neointimal VI at 6 months. Baseline reference vessel diameter was similar between the 1-mm larger diameter group and the 2-mm larger diameter group (5.0±0.8 mm vs. 4.7±0.9 mm, P=0.35). Stent diameter was 6.3±0.6 mm in the 1-mm larger group and 7.1±0.6 mm in the 2-mm larger group (P<0.0001), and stent to reference vessel diameter ratio (SV ratio) was 1.3±0.2 and 1.5±0.2 (P<0.0001), respectively. At 6-month, neointimal VI was greater in the 2-mm larger diameter group (5.5±1.5 mm²vs. 9.6±3.4 mm², P<0.001). The correlation analysis revealed that degree of neointimal VI was positively correlated with SV ratio (r=0.43, P<0.01).

CONCLUSIONS

Implantation of self-expanding DES with a considerably high SV ratio resulted in neointimal hyperplasia in SFA lesions.

Assessment of Mortality and Factors Affecting Outcome of Use of Paclitaxel-Coated Stents and Bare Metal Stents in Femoropopliteal PAD

The use of drug-coated devices in intravascular therapy is aimed at preventing neointimal hyperplasia caused by excessive proliferation of vascular smooth muscle and thereby restenosis. Although its use seemed initially promising, a recent publication has shown an increased risk of mortality with paclitaxel-coated devices, and there is an urgent need to reaffirm assessments of drug-eluting stents (DES). Objective: The aim of the study was to compare mortality and effectiveness of paclitaxel-coated stents and bare-metal stents (BMS) in the treatment of peripheral arterial disease (PAD) with long-term follow-up. Materials and methods: In a single center randomized study, 256 patients with PAD were treated intravascularly with stent implantation. Patients were randomized into two groups: the first (n = 126) were treated with DES, and the second (n = 130) were treated with BMS. The study included evaluation after the procedure, after about 6 months and 36 months. Co-morbidities, with risks for atherosclerosis, were analyzed in all patients. Patients were evaluated for clinical outcome, restenosis frequency, and safety (complications and total mortality). Results: Clinical benefit at the end of the investigation was statistically significantly better in the DES group compared with the BMS group: 85.7% versus 66.2% (p = 0.0003), respectively. Restenosis occurred significantly less frequently in patients with DES: 16.0% versus BMS: 35.0%, p = 0.012. There was no significant effect of comorbidities on the frequency of restenoses. There were no differences in all-cause mortality over the three years with paclitaxel and no-paclitaxel stents cohorts (8.7% versus 7.1%; long-rank p = 0.575). No association was found with mortality and treatment with DES or BMS. Conclusions: The use of paclitaxel-coated stents gave good clinical benefit and caused a significantly lower frequency of restenosis compared to bare-metal stents. The use of paclitaxel-coated stents did not increase mortality.

Endovascular Intervention for the Treatment of Trans-Atlantic Inter-Society Consensus (TASC) D Femoropopliteal Lesions: A Systematic Review and Meta-Analysis

PURPOSE

Advancements in the endovascular treatment of femoropopliteal atherosclerotic lesions have led to treatment of more complex lesions, particularly long lesions. The aim of this study was to determine the meta-analytic primary patency and need for re-intervention among patients treated for very long lesions (>200 mm) at the femoropopliteal segment and to identify potential risk factors for loss of patency.

METHODS

This study was performed according to the PRISMA guidelines. A random effects model meta-analysis was conducted, and the I-square was used to assess heterogeneity.

RESULTS

Fifty-one studies comprised of 3029 patients were included. The mean lesion length was 269 mm. The primary patency rate at 30 days, 6 m, 1-, 2- and 5-years of follow-up was 98%, 76%, 62%, 55%, and 39% respectively. The incidence of TLR was 16% at one year and 32% at two years. The secondary patency rate at 1, 2, 3 and 5 years was 85%, 71%, 64%, and 64% respectively. Heparin bonded ePTFE covered stents (69%) and paclitaxel eluting stents (73%) demonstrated higher 1-year primary patency rates than self-expanding nitinol stents (55%) or uncoated percutaneous transluminal angioplasty (PTA) with provisional stenting (54%). Lesions treated with a heparin bonded ePTFE covered stent had statistically significant higher odds of remaining patent at 1-year of follow-up (OR: 2.74; 95%CI: 1.63-4.61; p < 0.001) than lesions treated with BMS or PTA. Patients with long femoropopliteal lesions causing critical limb ischemia (CLI) developed restenosis or occlusion more often than patients treated for claudication (HR: 1.63; 95%CI: 1.06-2.49; p = 0.026) during an average follow-up of 26 months.

CONCLUSION

Primary stenting of femoropopliteal TASC D lesions using drug eluting stents or covered stents results in sustained patency over time. PTA or uncoated nitinol stents demonstrated lower patency rates. However, additional comparative studies are needed to determine the efficacy of newer technologies for the treatment of complex femoropopliteal lesions and provide evidence for the most optimal treatment approach.

Current developments in endovascular therapy of peripheral vascular disease

More than 200 million people worldwide have peripheral artery disease (PAD) or its most severe manifestation, critical limb ischemia (CLI). While endovascular treatment has become first line therapy in most cases, a number of challenges remain for optimal treatment of femoropopliteal (FP) or infrapopliteal (IP) disease, especially when these lesions are severely calcified, chronic total occlusions (CTOs) or in-stent restenosis (ISR). Continued evolution of technologies has significantly improved the outcomes for endovascular treatment. A number of new devices are in the pipeline right now, including new paclitaxel eluting stents and balloons, intravascular lithotripsy to treat severely calcified lesions, adventitial delivery of anti-restenotic agents to limit restenosis rates, and percutaneous femoro-popliteal bypass.

Endovascular treatment of atherosclerotic lesions in the superficial femoral artery and proximal popliteal artery using the sinus-SuperFlex-635 stent: twelve-month results from the HERO Registry

BACKGROUND

The aim of this study was to evaluate the safety and performance of the sinus-SuperFlex-635 self-expandable nitinol stent (Optimed GmbH) for the treatment of steno-occlusive lesions in the superficial femoral artery (SFA) and proximal popliteal artery (PPA).

METHODS

The prospective, multicenter, observational HERO study recruited 117 eligible patients (83 men; mean age 69.4±9.7y) from 7 centers in Belgium.

RESULTS

A total of 129 stents were successfully deployed in 121 lesions in 117 patients (100%). The patients presented with symptomatic ≥50% stenosis or chronic total occlusion (CTO) (30.6%). Mean lesion length was 71.4±56.3 mm. Moderate to severe calcification was present in 82.6% of the lesions. Acute lesion success (<30% residual stenosis) was achieved in 96.0%. There were no in-hospital serious adverse events. Duplex ultrasound-driven primary patency at 12 months was recorded in 84 of 107 (78.5%) lesions. The overall target lesion revascularization (TLR) rate was 8.4% at 12 months; the target extremity revascularization (TER) rate was 4.7%. Clinical assessment at 12 months demonstrated improvement by at least 1 Rutherford class, without the need for TLR (i.e. primary sustained clinical improvement) in 83.9% of patients and with the need for TLR in 90.6% of patients (i.e. secondary sustained clinical improvement).

CONCLUSIONS

Based on the high primary patency, low stent fracture rate and significant clinical improvement, combined with refined stent design and long stent availability, the sinus-SuperFlex-635 self-expandable nitinol stent proves its value in the treatment of complex femoropopliteal lesions.

ZILVERPASS Study: ZILVER PTX Stent vs Bypass Surgery in Femoropopliteal Lesions

Purpose: To report the 12-month results of a multicenter, prospective, randomized controlled trial to determine if the ZILVER PTX paclitaxel-eluting stent was noninferior in terms of safety and efficacy compared with surgical bypass. Materials and Methods: This is a study in symptomatic TransAtlantic Inter-Society Consensus (TASC) C and D femoropopliteal lesions comparing endovascular ZILVER PTX stenting vs surgical bypass surgery using a prosthetic graft ( ClinicalTrials.gov identifier NCT01952457). Between October 2013 and July 2017, 220 patients (mean age 68.6±10.5 years; 159 men) were enrolled and randomized to the ZILVER PTX treatment group (113, 51.4%) or the bypass treatment group (107, 48.6%). Most of the lesions were occlusions (208, 94.5%); the mean lesion length was 247.1±69.3 mm. The primary outcome measure was primary patency at 12 months, defined as no evidence of binary restenosis or occlusion within the target lesion or bypass graft based on a duplex-derived peak systolic velocity ratio <2.4 and no clinically-driven target lesion revascularization (TLR) in endovascular cases or reintervention to restore flow in the bypass. Results: The estimated 12-month primary patency rate was 74.5% (95% CI 66.3% to 82.7%) for the ZILVER PTX group vs 72.5% (95% CI 63.7% to 81.3%) for the bypass arm (p=0.998). Freedom from TLR at 12 months was 80.9% (95% CI 73.3% to 88.5%) for the ZILVER PTX group vs 76.2% (95% CI 68.0% to 84.4%) for the bypass group (p=0.471). The 30-day complication rate was significantly lower in the ZILVER PTX group (4.4% vs 11.3%, p=0.004). Also, procedure time and hospital stay were significantly shorter in the ZILVER PTX group (p<0.001 for both). Conclusion: With noninferior patency results, a lower complication rate, and shorter procedures and hospital stays, paclitaxel-eluting stenting might become a recommended treatment for long TASC C and D femoropopliteal lesions.

Effectiveness and Safety of a Paclitaxel-Eluting Stent for Superficial Femoral Artery Lesions up to 190 mm: One-Year Outcomes of the Single-Arm IMPERIAL Long Lesion Substudy of the Eluvia Drug-Eluting Stent

Purpose: To report the clinical effect of a drug-eluting stent on femoropopliteal occlusive disease in patients with long lesions. Materials and Methods: The global IMPERIAL Long Lesion substudy (ClinicalTrials.gov identifier NCT02574481) is a prospective, single-arm, multicenter trial of the Eluvia Drug-Eluting Vascular Stent for treating femoropopliteal lesions >140 mm and ≤190 mm in length. Fifty patients (mean age 68.2 years; 32 men) with long lesions (mean length 162.8±34.7 mm) were enrolled; 20 patients had diabetes. Fourteen of the lesions were severely calcified and 16 were occluded. Primary patency (duplex ultrasound peak systolic velocity ratio ≤2.4 in the absence of clinically-driven target lesion revascularization or bypass of the target lesion) and major adverse events [30-day all-cause death and 1-year target limb major amputation or target lesion revascularization (TLR)] were assessed at 12 months. Results: At 12 months, no deaths, target limb amputations, or stent thrombosis had occurred. The Kaplan-Meier estimate of primary patency was 91.0% (95% CI 82.5% to 99.6%). The MAE-free rate at 12 months was 93.5% due to 3 clinically-driven TLRs. The corresponding Kaplan-Meier estimate of freedom from TLR was 93.9% (95% CI 87.2% to 100%). Conclusion: The IMPERIAL Long Lesion substudy demonstrated excellent patency and safety through 1 year among patients with long femoropopliteal occlusive disease treated with the Eluvia stent.

Impact of IVUS-Derived Vessel Size on Midterm Outcomes After Stent Implantation in Femoropopliteal Lesions

Purpose: To identify intravascular ultrasound (IVUS) findings that predict midterm stent patency in femoropopliteal (FP) lesions. Materials and Methods: A retrospective analysis was undertaken of 335 de novo FP lesions in 274 consecutive patients (mean age 72.4±8.2 years; 210 men) who had IVUS assessment before and after successful stent implantation. The mean lesion length was 13.2±9.8 cm. The primary outcome was primary patency at 24 months, defined as freedom from major adverse limb event (MALE) and in-stent restenosis (ISR). MALE was defined as major amputation or any target lesion revascularization (TLR). ISR was defined by a peak systolic velocity ratio >2.4 by duplex ultrasonography. Logistic regression analyses were performed to identify independent predictors of stent patency at 24 months; the results are presented as the odds ratio (OR) and 95% confidence interval (CI). Receiver operator characteristic (ROC) curve analysis was performed to determine the optimal threshold for prediction of stent patency at 24 months. Results: Over the 24-month follow-up, 18 (7%) patients died and 43 (15%) of 286 lesions were responsible for MALE (42 TLRs and 1 major amputation). Primary patency was estimated at 82.5% (95% CI 78.1% to 86.9%) at 12 months and 73.2% (95% CI 67.9% to 78.5%) at 24 months. Multivariable analysis revealed that longer lesion length (OR 0.89, 95% CI 0.82 to 0.97, p<0.01) was an independent predictor of declining patency, while cilostazol use (OR 3.45, 95% CI 1.10 to 10.78, p=0.03) and increasing distal reference external elastic membrane (EEM) area (OR 1.18, 95% CI 1.02 to 1.37, p=0.03) were associated with midterm stent patency. ROC curve analysis identified a distal reference EEM area of 29.0 mm² as the optimal cut-point for prediction of 24-month stent patency (area under the ROC curve 0.764). Kaplan-Meier estimates of 24-month primary patency were 83.7% (95% CI 78.3% to 89.2%) in lesions with a distal EEM area >29.0 mm² vs 53.1% (95% CI 42.9% to 63.3%) in those with a distal EEM area ≤29.0 mm² (p<0.001). Conclusion: In FP lesions with a larger distal vessel area estimated with IVUS, stent implantation can be considered as a reasonable treatment option, with the likelihood of acceptable midterm results.

1-Year All-Comers Analysis of the Eluvia Drug-Eluting Stent for Long Femoropopliteal Lesions After Suboptimal Angioplasty

OBJECTIVES

The aim of this study was to assess the performance of the fluoropolymer-based paclitaxel-eluting stent (PES) in long femoropopliteal lesions.

BACKGROUND

The new-generation fluoropolymer-based PES showed promising outcomes in short femoropopliteal lesions. The main feature of the stent is its controlled and sustained paclitaxel release over 12 months. However, the safety and efficacy of this technology in longer femoropopliteal lesions remain unclear.

METHODS

Between March 2016 and March 2017, 62 patients were included in this analysis. Indications for fluoropolymer-based PES deployment were insufficient luminal gain or flow-limiting dissection after plain old balloon angioplasty in a femoropopliteal lesion. Primary patency, freedom from target lesion revascularization, amputation-free survival, and paclitaxel-related adverse events were retrospectively analyzed for up to 1 year of follow-up.

RESULTS

Lesions were de novo in 84% of patients. Mean lesion length was 20 ± 12 cm, and 79% of the lesions (n = 49) were chronic total occlusions. Moderate or severe calcification was present in 42% of the lesions (n = 26). Stent implantation involved the distal superficial femoral artery and the proximal popliteal artery in 76% (n = 47) and 44% (n = 27) of patients, respectively. The Kaplan-Meier estimate of primary patency and freedom from target lesion revascularization was 87%. Amputation-free survival was 100% for patients with claudication (n = 32 [52%]) and 87% in patients with critical limb ischemia (n = 30 [48%]) (hazard ratio: 6.3; 95% confidence interval: 1.25 to 31.54; p = 0.052). Five aneurysm formations of the treated segments (8%) were thought to be attributable to paclitaxel.

CONCLUSIONS

The fluoropolymer-based PES showed promising 1-year clinical and angiographic outcomes in real-world long femoropopliteal lesions. The long-term impact of aneurysm formation remains to be further investigated.

Paclitaxel-Coated Zilver PTX Drug-Eluting Stent Treatment Does Not Result in Increased Long-Term All-Cause Mortality Compared to Uncoated Devices

Purpose

Patient-level data from two large studies of the Zilver PTX drug-eluting stent (DES) with long-term follow-up and concurrent non-drug comparator groups were analyzed to determine whether there was an increased mortality risk due to paclitaxel.

Methods

Data from the Zilver PTX randomized controlled trial (RCT) and Zilver PTX and bare metal stent (BMS) Japan post-market surveillance studies were analyzed. Five-year follow-up is complete in both DES studies; follow-up for the BMS study was limited to 3 years and is complete. Kaplan–Meier analyses assessed mortality. A Cox proportional hazards model identified significant factors related to mortality.

Results

In the RCT, there were 336 patients treated with the DES and 143 patients treated with percutaneous transluminal angioplasty (PTA) or BMS. In Japan, there were 904 DES patients and 190 BMS patients. There was no difference in all-cause mortality for the DES compared to PTA/BMS in the RCT (19.1% DES versus 17.1% PTA/BMS through 5 years, p = 0.60) or Japan (15.8% DES versus 15.3% BMS through 3 years, p = 0.89). Cox proportional hazard models revealed that age, tissue loss, and congestive heart failure were significantly associated with mortality in the RCT, and critical limb ischemia, age, renal failure, and gender were significantly associated with mortality in Japan (all p < 0.05). Neither treatment with Zilver PTX (p = 0.46 RCT, p = 0.49 Japan) nor paclitaxel dose (p = 0.86 RCT, p = 0.07 Japan) was associated with mortality.

Conclusion

Analyses of the Zilver PTX patient-level data demonstrated no increase in long-term all-cause mortality.

Level of Evidence

Zilver PTX RCT: Level 1, randomized controlled trial; Japan PMS studies: Level 3, post-market surveillance study.

Electronic supplementary material

The online version of this article (10.1007/s00270-019-02324-4) contains supplementary material, which is available to authorized users.

Assessment of Vascular Patency and Inflammation with Intravascular Optical Coherence Tomography in Patients with Superficial Femoral Artery Disease Treated with Zilver PTX Stents

PURPOSE

Zilver PTX nitinol self-expanding drug-eluting stent with paclitaxel coating is effective for treatment of superficial femoral artery (SFA) disease. However, as with any stent, it induces a measure of vascular inflammatory response. The current clinical trial (NCT02734836) aimed to assess vascular patency, remodeling, and inflammatory markers with intravascular optical coherence tomography (OCT) in patients with SFA disease treated with Zilver PTX stents.

METHODS

Serial OCT examinations were performed in 13 patients at baseline and 12-month follow-up. Variables evaluated included neointimal area, luminal narrowing, thrombus area, stent expansion as well as measures of inflammation including, peri-strut low-intensity area (PLIA), macrophage arc, neovascularization, stent strut apposition and coverage.

RESULTS

Percentage of malapposed struts decreased from 10.3 ± 7.9% post-intervention to 1.1 ± 2.2% at 12-month follow-up, but one patient showed late-acquired stent malapposition (LASM). The percent of uncovered struts at follow-up was 3.0 ± 4.5%. Average expansion of stent cross-sectional area from baseline to follow-up was 35 ± 19%. The average neointimal area was 7.8 ± 3.8 mm². Maximal luminal narrowing was 61.1 ± 25.0%, and average luminal narrowing was 35.4 ± 18.2%. Average peri-strut low-intensity area (PLIA) per strut was 0.017 ± 0.018 mm². Average number of neovessels per mm of stent was 0.138 ± 0.181. Average macrophage angle per frame at follow-up was 7 ± 11°. Average thrombus area at follow-up was 0.0093 ± 0.0184 mm².

CONCLUSION

At 12-month follow-up, OCT analysis of Zilver PTX stent shows outward remodeling and minimal neointimal growth, but evidence of inflammation including PLIA, neovessels, thrombus and macrophages.

SUMMARY

Thirteen patients with PAD had paclitaxel-coated stents implanted in their SFAs and were then imaged with OCT at baseline and 12-month follow-up. OCT proxy metrics of inflammation were quantified.

Vessel Calcification as a Risk Factor for In-Stent Restenosis in Complex Femoropopliteal Lesions After Zilver PTX Paclitaxel-Coated Stent Placement

Purpose: To evaluate the effect of vessel calcification on in-stent restenosis (ISR) after drug-coated stent (DCS) placement in the femoropopliteal segment. Materials and Methods: A retrospective multicenter study was undertaken involving 220 consecutive symptomatic patients (mean age 73.1±8.3 years; 175 men) with femoropopliteal lesions in 230 limbs treated with the Zilver PTX DCS and having duplex surveillance after the endovascular procedures. Mean lesion length was 16.4±9.8 cm (range 2–40); there were 104 (45.2%) total occlusions and 68 (29.6%) in-stent restenoses (ISR). Twenty (8.7%) vessels had no runoff. The majority of lesions (148, 64.3%) were calcified according to the peripheral arterial calcium scoring system (PACSS). Primary patency was evaluated by duplex. Lesions were classified as either PACSS 0–2 (none or unilateral wall calcification) or PACSS 3 and 4 (bilateral wall calcification). Multivariate analysis was performed to identify variables associated with ISR; the results are given as the hazard ratio (HR) and 95% confidence interval (CI). Results: The 1-, 2-, and 5-year primary patency and freedom from clinically-driven target lesion revascularization estimates were 75.9%, 63.6%, and 45.0%, and 84.7%, 73.7%, and 54.2%, respectively. Major amputations were performed on 4 limbs during follow-up. In multivariate analysis, vessel calcification (adjusted HR 1.718, 95% CI 1.035 to 2.851, p=0.036) was significantly correlated with the occurrence of ISR, along with lesion length (adjusted HR 1.041, 95% CI 1.013 to 1.070, p=0.003), and cilostazol administration (adjusted HR 0.476, 95% CI 0.259 to 0.876, p=0.017). Conclusion: This study suggested that bilateral vessel wall calcification was an independent risk factor for ISR in complex femoropopliteal lesions after Zilver PTX DCS placement, along with lesion length; cilostazol administration had a protective effect.

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-eluting stents for PAD: what does (all) the data tell us?

When the FDA approved the use of a paclitaxel-coated stent in the peripheral arteries in November of 2012, a new era in the treatment of peripheral arterial disease (PAD) emerged. This marked, for the first time in the United States, that a drug-eluting device was available to treat this complex arterial bed, and has likely changed forever how PAD is treated. Prior to this, US physicians had been using drug-eluting stents (DES) in the coronary arteries for 8 years with exceptional results in both safety and efficacy. Since the Zilver®PTX® (Cook Medical, Bloomington, IN USA) was released, multiple drug-coated balloons (DCB) with paclitaxel have been approved in the US, as has another DES, the Eluvia™ stent (Boston Scientific, Minneapolis, MN USA).

Antithrombotic therapy after femoropopliteal artery stenting: 12-month results from Japan Postmarketing Surveillance

Objective

To investigate the effects of antithrombotic therapy on target lesion revascularisation (TLR) and major adverse cardiovascular and cerebrovascular events (MACCEs) at 12 months after femoropopliteal intervention with second-generation bare metal nitinol stents.

Methods

A total of 277 lesions in 258 limbs of 248 patients with de novo atherosclerosis in the above-the-knee femoropopliteal segment were analysed from the Japan multicentre postmarketing surveillance.

Results

At discharge, dual antiplatelet therapy (DAPT) was prescribed in 68.5% and cilostazol in 30.2% of patients. At 12 months of follow-up, prescriptions of DAPT significantly (p=0.0001) decreased to 51.2% and prescription of cilostazol remained unchanged (p=0.592) at 28.0%. Prescription of warfarin also remained unchanged (14.5% at discharge, 13.3% at 12 months, p=0.70). At 12 months, freedoms from TLR and MACCE were 89.4% and 89.7%, respectively. In a multivariate Cox proportional hazards model, neither DAPT nor cilostazol at discharge was associated with both TLR and MACCE at 12 months. However, warfarin at discharge was only independently associated with TLR at 12 months. Kaplan-Meier estimates demonstrated that warfarin at discharge yielded a significantly (p=0.013) lower freedom from TLR at 12 months than no warfarin at discharge. Freedom from TLR at 12 months by the Kaplan-Meier estimates was 77.8% (95% CI 59.0% to 88.8%) in patients with warfarin at discharge and 91.2% (95% CI 86.3% to 94.3%) in those without warfarin at discharge.

Conclusions

Clinical benefits of DAPT or cilostazol might be small in terms of TLR and MACCE at 12 months. Anticoagulation with warfarin at discharge might increase TLR at 12 months.

Drug-coated balloons versus drug-eluting stents in the femoropopliteal artery: comparing apples to oranges?

Superficial femoral and popliteal artery disease are commonly involved in the development of symptomatic PAD. As time has gone on drug coated stents and drug coated balloons have supplanted the plain balloon angioplasty corner stone of therapy with superiority proven in randomized trials. Device approval trials are typically characterized by simple lesions that are less common than the longer complex disease. Registry data has demonstrated benefit of both technologies though drug coated balloons typically require a significant amount of adjunctive stenting in more complex disease. Recently published randomized data is starting to help proceduralists define when each therapy may be more optimal.

Drug-coated balloon versus uncoated percutaneous transluminal angioplasty for the treatment of atherosclerotic lesions in the superficial femoral and proximal popliteal artery: 2-year results of the MDT-2113 SFA Japan randomized trial

OBJECTIVES

To assess the longer-term safety and efficacy of the IN.PACT Admiral (MDT-2113) drug-coated balloon (DCB) for the treatment of de novo and non-stented restenotic lesions in the superficial femoral and/or proximal popliteal arteries versus uncoated percutaneous transluminal angioplasty (PTA) in a Japanese cohort.

BACKGROUND

Although DCBs are the newest endovascular strategy for patients with peripheral artery disease presenting with femoropopliteal lesions, there remains a paucity of results in non-Caucasian populations.

METHODS

IN.PACT SFA Japan is an independently-adjudicated, prospective, multicenter, randomized, single-blinded trial. Endpoints through 2 years included primary patency and a composite safety endpoint of freedom from device- and procedure-related death through 30 days, freedom from target limb major amputation and freedom from clinically-driven target vessel revascularization at 24 months.

RESULTS

One hundred patients were assigned by 2:1 randomization to treatment with the IN.PACT Admiral DCB (n = 68) or PTA (n = 32). The groups were well-matched at baseline. Mean lesion length for the DCB and PTA groups were 9.15 ± 5.85 and 8.89 ± 6.01 cm (P = 0.838), respectively. Patients treated with DCB exhibited superior 24-month primary patency compared to PTA (79.8% vs. 46.9%; log rank P < 0.001). The 24-month clinically driven target lesion revascularization rate was 9.1% for DCB versus 20.7% for PTA (P = 0.177). There were no device- or procedure-related deaths, major amputations, or thromboses in either group.

CONCLUSIONS

Two-year results from IN.PACT SFA Japan demonstrated persistently superior patency and low CD-TLR rates through 2 years when compared to uncoated PTA in Japanese patients. These data are consistent with other IN.PACT DCB trials.

Drug-Eluting Balloons and Drug-Eluting Stents in the Treatment of Peripheral Vascular Disease

In the last 20 years, peripheral artery disease (PAD) has been increasingly recognized as a significant cause of morbidity and mortality in the United States. The endovascular treatment of PAD has seen a marked rise as minimally invasive techniques and devices have been refined. Two newer devices, drug-eluting stents and drug-eluting balloons, are on the forefront of the battle against limb loss from PAD. This review focuses on the data backing the use of drug-eluting technologies for use in the peripheral arterial system.

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.

EVOLUTION Study: 12-month results

BACKGROUND

The EVOLUTION Study is a prospective, non-randomized study, investigating the iVolution stent (iVascular, Barcelona, Spain). The study was conducted at the vascular departments of four hospitals in Belgium. This manuscript reports the findings up to 12-month follow-up time for the total cohort. The primary endpoint of the study is primary patency at 12 months. Primary patency is defined as a target lesion without a hemodynamically significant stenosis on duplex ultrasound (>50%, systolic velocity ratio no greater than 2.4) and without Target Lesion Revascularization (TLR) within 12 months.

METHODS

Between April 2015 and November 2016, 120 patients with TASC A&B femoropopliteal lesions were included. The mean lesion length was 89.63 mm. Most of the lesions were stenotic lesions (60.00%).

RESULTS

Primary patency rate for the total patient population was 86.30% at 12-month follow-up. Freedom from TLR at 12-month was 88.00%.

CONCLUSIONS

These results confirm the already existing enthusiasm of the use of bare metal self-expandable nitinol stents in the treatment of TASC A&B femoropopliteal lesions. Longer follow-up and a comparison or addition with drug-eluting technology has to be studied in the future.

Zilver PTX Post-market Surveillance Study of Paclitaxel-Eluting Stents for Treating Femoropopliteal Artery Disease in Japan: 2-Year Results

Purpose

A prospective, multicenter post-market surveillance study in Japan evaluated the 2-year safety and effectiveness of the DES in real-world patients with complex femoropopliteal artery lesions.

Methods

There were no exclusion criteria, and consecutive symptomatic patients with femoropopliteal lesions treated with the DES were enrolled in the study. Clinically driven target lesion revascularization (TLR) was defined as reintervention performed for > 50% diameter stenosis after recurrent clinical symptoms of peripheral arterial disease. Clinical benefit was defined as freedom from persistent or deteriorating ischemic symptoms. Patency was evaluated by duplex ultrasound where physicians considered this standard of care.

Results

In this study, 905 patients were enrolled at 95 institutions in Japan. There were numerous comorbidities including a high incidence of diabetes (58.8%) and chronic kidney disease (43.6%). Additionally, 21.4% of patients were classified with critical limb ischemia. Lesions were complex, with an average length of 14.6 ± 9.6 cm (range 0.5–40 cm), 41.5% total occlusions, and 18.7% in-stent restenosis. In total, 1861 DES were placed in 1080 lesions. Two-year follow-up was obtained for > 90% of eligible patients. Freedom from TLR was 83.7%, and clinical benefit was 80.0% through 2 years. The 2-year primary patency rate was 70.3%. Rutherford classification significantly improved (p < 0.01), with approximately 80% of patients classified as Rutherford class 0 or 1 at 2 years.

Conclusion

Despite more challenging lesion characteristics, 2-year results from the current study are similar to outcomes from the previous Zilver PTX studies, confirming the efficacy of the Zilver PTX DES in a complicated femoropopliteal lesion (Zilver PTX Post-Market Study in Japan; NCT02254837).

Level of Evidence

Post-market surveillance study, Level III.

Drug-eluting stents for the treatment of complex femoro-popliteal disease: a systematic review and meta-analysis

INTRODUCTION

Endovascular methods have emerged as an appealing alternative to bypass for the treatment of patients not suitable for surgery. Drug eluting stents (DES) have been developed to address the limitations of angioplasty and stenting. There is a paucity of data in the literature on their performance for the treatment of patients with long femoro- popliteal segment lesions. We aimed to analyse the evidence supporting the use of DES in patients with complex femoro-popliteal disease.

EVIDENCE ACQUISITION

A systematic review and meta-analysis was conducted according to the recommendations of the Preferred Reporting Items for Systematic reviews and Meta- Analyses (PRISMA) statement.

EVIDENCE SYNTHESIS

A total of 1255 potentially relevant articles were initially selected. After reviewing at title or abstract level, 22 articles were read in full and 10 were included. These studies reported on the use of DES for 1539 patients. In all studies the DES that was employed was a paclitaxel-eluting stent (Zilver PTX, Cook Medical). Average lesion length ranged from 114mm to 400mm. The pooled technical success rate was 0.964 (95% confidence interval [CI]: 0.936 - 0.980). The pooled estimate of limb loss at 12 months was 0.019 (95% CI: 0.012 - 0.030), stent fracture at 12 months 0.035 (95% CI: 0.007 - 0.155), primary patency at 12 months 0.705 (95% CI: 0.576 - 0.807) and secondary patency at 12 months 0.898 (95% CI: 0.815 - 0.946).

CONCLUSIONS

The short-term outcomes of DES for TASC C & D femoro-popliteal lesions are encouraging. Caution is advised in extrapolating the results of the included studies due to the large heterogeneity and lack of reporting of subgroup specific outcomes.

Drug-Eluting Stents for Treatment of Peripheral Artery Disease

Endovascular intervention is a mainstay treatment of peripheral artery disease (PAD) in addition to aggressive risk factor modification and exercise programs in patients with favorable anatomy or in those who are considered too high risk for surgical intervention. Treatment with percutaneous transluminal angioplasty (PTA) and bare metal stents (BMS) has been limited by high rates of in-stent restenosis (ISR) requiring repeat revascularization. Drug-eluting stents (DES), developed and designed to reduce ISR, offer a promising solution to the current challenges in endovascular management of PAD. Several randomized clinical trials have shown improved short- and mid-term outcomes with DES as compared with both PTA and BMS. Herein we provide an up-to-date review of the current literature on DES use in PAD.

Failure mode and bimodal restenosis of drug-coated balloon in femoropopliteal intervention

BACKGROUND

Pattern of DCB restenosis and associated outcomes in facing complex femoropopliteal lesions remain uncertain.

METHODS

Data were retrospectively collected from dual centers in Taiwan on patients who underwent treatment with DCBs for femoropopliteal lesions between 2013 and 2016. The restenosis pattern was categorized by the index-treated length. Clinical outcomes and time to DCB restenosis were retrospectively analyzed. Cox proportional hazards model identified restenosis predictors.

RESULTS

We recruited a total of 164 patients (91 men; median age 73 years) into the final analysis. The mean lesion length was 204.0 ± 109.2 mm. Of them, 45% total occlusions, 28% severe calcification and 15% in-stent restenosis were treated. Fifty-five patients have DCB restenosis (28 focal and 27 diffuse-occlusive patterns) over a 55-month follow-up. The median restenosis time emerged as a bimodal pattern with a significant difference between the diffuse-occlusive and focal restenosis group (225 vs. 484 days, P = 0.01). The 1-year patency rate after reintervention for DCB restenosis also was different between both restenosis group (29% vs. 65%, P = 0.017). The anticipated timing of escape for diffuse-occlusive or focal restenosis was 687 and 1068 days, respectively. Independent factors were lesion length (P = 0.049) for diffuse-occlusive restenosis and lumen gain of the popliteal artery for focal restenosis (P = 0.034).

CONCLUSIONS

This study demonstrated time to DCB failure emerged as a bimodal pattern of distribution and associations of restenosis pattern to subsequent outcomes after the repeated intervention. Exemption from late catchup restenosis required 3-year observation instead of the 1-year mark for conventional treatment.

Real-World Comparison of Drug-Eluting and Bare-Metal Stents in Superficial Femoral Artery Occlusive Disease with Trans-Atlantic Intersociety Consensus B Lesions: A 2-Year, Single-Institute Study

Background

Endovascular stenting has surpassed bypass surgery to become the first-line treatment for superficial femoral artery (SFA) occlusive disease, and various types of stents including bare-metal stents (BMSs), covered stents, and drug-eluting stents (DESs), have been approved for treatment. This retrospective, single-institute study compared the short-term, real-world outcomes of BMSs and DESs for treating SFA occlusive disease.

Methods

A retrospective chart review was used to enroll 94 patients who received a DES (n = 24) or BMS (n = 70) between 2009 and 2014. All patients had SFA occlusive disease with critical limb ischemia and an intermediate length of SFA occlusion [Trans-Atlantic Intersociety Consensus (TASC)-II B lesions] and were regularly followed for 2 years. All patient characteristics, procedural details, and outcomes were recorded.

Results

The 1-year primary patency rates in the BMS and DES groups were 71.4% and 87.5% (p = 0.169), respectively, and the corresponding 2-year rates were 61.4% and 79.2% (p = 0.139). The target lesion revascularization rate was 38.6% versus 20.8% (p = 0.139), the in-stent restenosis rate was 22.9% versus 0% (p = 0.009), the major limb amputation rate was 4.3% versus 0% (p = 0.568), the peripheral arterial disease-related mortality rate was 8.6% versus 0% (p = 0.332), and the all-cause mortality rate was 11.4% versus 0% (p = 0.109), respectively.

Conclusions

The 2-year results revealed higher safety, superior efficacy, and greater clinical benefits of DESs than BMSs for treating TASC-II B SFA occlusive disease. However, more cases and long-term follow-up are warranted.

Full Drug-Eluting Stent Jacket: Two-Year Results of a Single-Center Experience With Zilver PTX Stenting for Long Lesions in the Femoropopliteal Arteries

Purpose: To evaluate the 1- and 2-year patency and reintervention rates with the Zilver PTX drug-eluting stent (DES) in long complex femoropopliteal disease. Methods: A retrospective review was conducted of 89 consecutive patients (mean age 68.7±9.8 years; 86 men) with femoropopliteal occlusive disease (Rutherford category 2–6) treated with the Zilver PTX between December 2012 and December 2013. Mean lesion length for the entire cohort was 24.2±11.3 cm (median 24.0, range 4–48). The patient population was dichotomized into a short lesion (≤20 cm) group (n=41; mean lesion length 13.3±5.6 cm) and the full DES jacket (>20 cm) group (n=48; mean lesion length 33.0±6.5 cm). Primary endpoints were duplex-derived restenosis (peak systolic velocity ratio >2.5), clinically driven reintervention, and major amputation. Results: The incidence of restenosis was lower in the short lesion group at 1 year (19% vs 40% for the longer lesions, p=0.050) and 2 years (39% vs 54%, respectively; p=0.331). The short lesion group had significantly lower rates of reintervention at both 1 year (2% vs 21% in long lesions, p=0.009) and 2 years (12% vs 33%, p=0.019). Conclusion: Treatment of femoropopliteal lesions >20 cm with the Zilver PTX appears to be a clinically effective therapy for patients with symptomatic peripheral artery disease. However, there is an increase in restenosis and a need for reintervention that continues to progress up to 2 years.

New Regulatory Framework for Medical Devices in Japan: Current Regulatory Considerations Regarding Clinical Studies

In Japan, a recent issue that required an urgent response was the streamlining of regulations concerning clinical trials of medical devices. On July 31, 2017, the Ministry of Health, Labour and Welfare enacted a new regulatory framework called the fast-break scheme for innovative medical devices aiming to expedite patient access while reducing the premarket regulatory burden of clinical trials and enhancing postmarketing commitments. The new framework is expected to provide greater benefits to patients who require access to new medical devices and to companies via improved transparency and predictability, as well as to reduce the social and medical cost incurred for medical innovation.

Public Health Impact of the Centers for Medicare and Medicaid Services Decision on Pass-Through Add-On Payments for Drug-Coated Balloons: A Call to Action

On Wednesday, November 1, 2017, the Centers for Medicare and Medicaid Services (CMS) made a public decision to end the transitional pass-through add-on payment for drug-coated balloons beginning January 1, 2018, without creating a new ambulatory payment classification rate for these devices. In this Viewpoint, the authors highlight the disconnect between the CMS's decision not to create a new ambulatory payment classification category for drug-coated balloons despite demonstrated clinical superiority. The authors believe this decision is more in line with a rigid fee-for-service payment system than a value-based system that encourages quality over quantity, and disadvantages both the elderly and the poor. They call on all who advocate for patients with peripheral artery disease to action, encouraging their engagement on CMS decisions regarding payment.

Comparison of Drug-Eluting Stent with Bare-Metal Stent Implantation in Femoropopliteal Artery Disease: A Systematic Review and Meta-Analysis

BACKGROUND

This study aimed to perform a systematic review and meta-analysis of current evidence comparing the drug-eluting stent (DES) with the bare-metal stent (BMS) in the treatment of femoropopliteal artery disease (FPAD).

METHODS

All relevant articles reporting the results of DES versus BMS implantation in FPAD were systematically searched in MEDLINE, EMBASE, and Cochrane database. Randomized controlled trial (RCT), cohort, and retrospective study were all included. The efficacy end points included late lumen loss (LLL), binary restenosis, primary patency rate, freedom from target lesion revascularization (TLR), and stent fracture. Related data of the follow-up outcomes were extracted and pooled. For each end point, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

A total of 9 studies with 776 patients were included in this meta-analysis. There was no statistically significant difference between the DES and BMS groups in terms of LLL at 6 months (standard mean difference = -0.37, P = 0.07); binary restenosis at 6, 12, and 24 months (OR = 0.44, P = 0.20; OR = 0.75, P = 0.74; and OR = 0.62, P = 0.36; respectively); primary patency rate at 6, 12, and 24 months (OR = 1.18, P = 0.73; OR = 1.43, P = 0.70; OR = 1.25, P = 0.68, respectively); freedom from TLR at 12 months (OR = 1.13, P = 0.79); and stent fracture at 6 months (OR = 1.67, P = 0.38). A sensitivity analysis demonstrated that there was a significant benefit in the DES group over the BMS group in binary restenosis at 6 months (OR = 0.22, P = 0.008) after excluding a retrospective study, whereas no significant difference was observed when eliminating any other study. A subgroup analysis did not reveal any significant difference between a subgroup (sirolimus-eluting stent or paclitaxel-eluting stent) and the BMS group in FPAD.

CONCLUSIONS

According to current evidence, DES was not superior to BMS in the treatment of FPAD. Further larger RCTs are needed to provide more evidence in the comparison between DES and BMS for FPAD.

Drug-Coated Balloon vs Standard Percutaneous Transluminal Angioplasty for the Treatment of Atherosclerotic Lesions in the Superficial Femoral and Proximal Popliteal Arteries: One-Year Results of the MDT-2113 SFA Japan Randomized Trial

Purpose: To assess the safety and effectiveness of the MDT-2113 (IN.PACT Admiral) drug-coated balloon (DCB) for the treatment of de novo and native artery restenotic lesions in the superficial femoral and proximal popliteal arteries vs percutaneous transluminal angioplasty (PTA) with an uncoated balloon in a Japanese cohort. Methods: MDT-2113 SFA Japan (ClinicalTrials.gov identifier NCT01947478) is an independently adjudicated, prospective, randomized, single-blinded trial that randomized (2:1) 100 patients (mean age 73.6±7.0 years; 76 men) from 11 Japanese centers to treatment with DCB (n=68) or PTA (n=32). Baseline characteristics were similar between the groups, including mean lesion length (9.15±5.85 and 8.89±6.01 cm for the DCB and PTA groups, respectively). The primary effectiveness outcome was primary patency at 12 months, defined as freedom from clinically-driven target lesion revascularization (CD-TLR) and freedom from restenosis as determined by duplex ultrasonography. The safety endpoint was a composite of 30-day device- and procedure-related death and target limb major amputation and clinically-driven target vessel revascularization within 12 months. Results: Patients treated with DCBs exhibited superior 12-month primary patency (89%) compared to patients treated with PTA (48%, p<0.001). The 12-month CD-TLR rate was 3% for DCB vs 19% for PTA (p=0.012). There were no device- or procedure-related deaths, major amputations, or thromboses in either group. Quality-of-life measures showed sustained improvement from baseline to 12 months in both groups. Conclusion: Results from the MDT-2113 SFA Japan trial showed superior treatment effect for DCB vs PTA, with excellent patency and low CD-TLR rates. These results are consistent with other IN.PACT SFA DCB trials and demonstrate the safety and effectiveness of this DCB for the treatment of femoropopliteal lesions in this Japanese cohort.

Safety of Zilver PTX Drug-Eluting Stent Implantation Following Drug-Coated Balloon Dilation in a Healthy Swine Model

Purpose: To compare the safety of Zilver PTX drug-eluting stents (DES) following drug-coated balloon (DCB) angioplasty or conventional balloon angioplasty (BA) in a healthy porcine iliofemoral artery model. Methods: DES implantation following DCB (DCB+DES) or BA (BA+DES) was assessed by angiography and histology in the nondiseased iliofemoral arteries of 20 animals, with sacrifice at 1, 3, and 6 months. Safety assessment compared quantitative measures of vessel integrity (eg, preservation of artery geometry, structure, and lumen dimensions; absence of aneurysm; malapposition) and histological parameters (eg, excessive inflammation). The percentage of uncovered struts could not be >30% per section and the endothelial cell loss had to be <50%. The vascular and skeletal muscle changes in the downstream regions were also assessed histologically for evidence of emboli. Results: No significant differences in safety parameters, including inflammation and endothelial cell loss, were observed between the 2 groups at all time points. Percentage of fibrin was significantly higher in DCB+DES at 3 months [20.0% (IQR 11.6, 28.4) vs BA+DES 4.2% (IQR 1.4, 9.6), respectively; p=0.04], with consistent trends between groups at all time points. Medial smooth muscle cell loss peaked at 1 month and was not statistically different between groups at any time point, although the loss was greater in the DCB+DES group. Sections with arterioles exhibiting paclitaxel-associated fibrinoid necrosis in downstream tissues were observed exclusively in the DCB group at 1 month (14.3% of sections) and 3 months (11.5%). Conclusion: This preclinical study suggests that Zilver PTX stent implantation is a safe strategy after DCB angioplasty and might be considered for patients who require stenting after DCB treatment.

Long-Term Effectiveness of the Zilver PTX Drug-Eluting Stent for Femoropopliteal Peripheral Artery Disease in Patients with No Patent Tibial Runoff Vessels-Results from the Zilver PTX Japan Post-Market Surveillance Study

PURPOSE

To evaluate 2-year results of the Zilver PTX (Cook Medical, Bloomington, Indiana) drug-eluting stent (DES) for femoropopliteal peripheral artery disease (PAD) in patients with no continuous patent infrapopliteal runoff arteries compared with patients with ≥ 1 continuous patent runoff vessels.

MATERIALS AND METHODS

A retrospective analysis of patients with femoropopliteal PAD enrolled in the Zilver PTX Post-Market Surveillance Study in Japan was performed. There were no exclusion criteria. Outcomes, including freedom from target lesion revascularization (TLR), patency, and clinical benefit, for the no-runoff group (n = 54) were compared with the runoff group (n = 846).

RESULTS

The 2 groups were similar in terms of demographics, lesion characteristics, and comorbidities (P > .05). There was a higher incidence of critical limb ischemia in the no-runoff group compared with the runoff group (44.8% vs 19.7%; P < .01). There were 3 amputations (5.6%) in the no-runoff group versus 7 amputations (0.8%) in the runoff group (P = .02). At 2 years, freedom from TLR rates were 81.3% versus 83.8% (P = .87), patency rates were 68.4% versus 70.7% (P = .95), and clinical benefit rates were 73.7% versus 80.0% (P = .16) in the no-runoff versus runoff group, respectively.

CONCLUSIONS

Results in patients with no continuous patent tibial runoff were favorable through 2 years and similar to results for patients with ≥ 1 continuous patent runoff vessels, indicating that the Zilver PTX DES may be a valid treatment option for patients with these difficult-to-treat lesions.