When Are Endovascular and Open Bypass Treatments Preferred for Femoropopliteal Occlusive Disease?

Endovascular Transvenous versus Open Femoropopliteal Bypass

Background and Objectives: Lower extremity arterial disease is one of the most prevalent manifestations of atherosclerosis. The results from numerous studies regarding the best revascularization method of an occluded superficial femoral artery have been conflicting. The aim of this study was to compare the patency of transvenous endovascular with open femoropopliteal bypass, both with vein and prosthetic grafts. To our knowledge, a direct patency comparison between transvenous endovascular and open femoropopliteal bypass has not been published. This could help elucidate which method is preferable and in which cases. Materials and Methods: Patients with complex TASC-C and D SFA lesions were offered endovascular transvenous or open bypass. A total of 384 consecutive patients with PAD requiring surgical treatment were evaluated for inclusion in this study. Three-year follow-up data were collected for 52 endovascular procedures, 80 prosthetic grafts, and 44 venous bypass surgeries. Bypass patency was investigated by Duplex US every 6 months. Kaplan-Meier plots were used to analyze primary, primary-assisted, and secondary patency for endovascular transvenous, autovenous, and prosthetic bypasses. Results: Primary, primary-assisted, and secondary patency in venous group at 3 years was 70.5%, 77.3%, and 77.3%, respectively. In the endovascular transvenous group, primary, primary-assisted, and secondary patency at 3 years was 46.2%, 69.2%, and 76.9%, respectively. The lowest patency rates at 3 years were noted in the prosthetic graft group with 22.5% primary, 26.6% primary-assisted, and 28.2% secondary patency. Conclusions: The saphenous vein is the best graft to perform in above-the-knee femoropopliteal bypass. Transvenous endovascular bypass is a viable option with comparable primary-assisted and secondary patency. Primary patency is substantially lower for endovascular transvenous compared to venous bypass. Patients treated with endovascular transvenous bypass will require a significant number of secondary procedures to provide optimal patency. Prosthetic grafts should only be used if no other option for bypass is available.

A systematic review of simulation training for lower extremity bypass procedures

OBJECTIVES

Simulation is used across surgical specialties for skill enhancement. The choice and assessment method of a simulator varies across literature. In the age of endovascular approach, trainees have limited exposure to open lower limb bypass procedures which needs attention. This review aims to assess the utility of simulation training in lower limb bypass surgery using Kirkpatrick's model.

METHODS

Using PRISMA statement, we included all the studies done on simulators in lower limb bypass surgical procedures for this systematic review. The primary outcome was to assess the effectiveness of different types of simulation used for lower limb bypass surgery using the Kirkpatrick's model for training evaluation.

RESULTS

An initial search identified 295 articles out of which 7 articles were found to be eligible for this systematic review. A variety of simulators were used including cadavers and synthetic models. Most studies (n=5) found the use of simulation as an effective tool in achieving technical competence. All the five studies we found at level 2 on Kirpatrick's model evaluation.

CONCLUSION

Most of the existing studies are at level 2 of Kirkpatrick's model which reflects learning changes in trainees after simulation. Feedback mechanism needs to be evolved where the improvement after simulation training can be gauged by its replication in clinical practice and improved patient care practices corresponding to the highest level of Kirkpatrick's model.

Three-Year Patency Results following Endovascular Transvenous Femoropopliteal Bypass

Background and Objectives: Peripheral artery disease is one of the most common vascular pathologies. There is an ongoing debate among specialists on whether open or endovascular revascularization is preferred in cases of complex superficial femoral artery (SFA) lesions. The purpose of this study was to assess patency results of a relatively new transvenous endovascular bypass device. This could add to existing evidence and aid in comparison between open and endovascular bypass. Materials and Methods: Patients with complex TASC-C and D SFA lesions who had indications for revascularization were identified. Prospective analysis of stent graft patency from 54 transvenous femoropopliteal bypass procedures was performed. Patency was assessed by Duplex ultrasound every six months. Kaplan–Meier analysis was performed to assess primary, primary-assisted, and secondary patency of transvenous bypass. Results: Following endovascular transvenous femoropopliteal bypass, 3-year graft primary, primary-assisted, and secondary patency was 43.8%, 66.3%, and 73.9%, respectively. Conclusions: Transvenous endovascular femoropopliteal bypass is a viable option for selected patients who lack adequate saphenous vein or have comorbidities that increase the risk of open femoropopliteal bypass. Strict post-operative follow-up is necessary to improve patency rates.

Popliteal endarterectomy for isolated popliteal arterial occlusive disease: A retrospective review study

OBJECTIVE

This study aims to assess the safety and viability of popliteal endarterectomy for isolated popliteal disease.

METHOD

The study is a retrospective review, single-institution review (2010-2020) which assessed all popliteal endarterectomies performed at a rural 180-bed teaching hospital. Cases were identified based on the CPT code. The decision for endarterectomy was based on favorable anatomy including focal disease limited to the popliteal artery able to be approached from a posterior approach. The electronic medical record was used to capture patient characteristics, procedural information, and follow-up data.

RESULTS

A total of 14 patients underwent popliteal endarterectomy (8 males and 6 females). The mean age was 61.9 (range of 29-78). The average follow-up period was 33.3 months. The indications for surgery were claudication in five patients, rest pain in four patients, and tissue loss in five patients. The average ABI preoperatively was 0.66 (range of 0.31-0.94). The average ABI postoperatively was 0.98 (range of 0.58-1.62), with an average change of +0.30 (range of -0.25 to +0.7). Complications included one seroma, one superficial wound infection, one early thrombosis requiring subsequent bypass, and one deep venous thrombosis. Two patients required angioplasty during follow-up for treatment of stenosis in order to maintain patency. The primary patency rate was 92.3% at discharge. At 23 months, the primary patency rate was 78% and the primary-assisted patency rate was 89%. All patients treated for claudication had resolution of symptoms. For patients treated for critical limb ischemia, all patients had resolution of rest pain and all wounds healed by 24 months.

CONCLUSION

In carefully selected patients, popliteal endarterectomy is a durable open surgical alternative to bypass, which preserves vein conduits with short operative times, low complication rates, and excellent long-term patency.

Revascularization Strategies for Patients With Femoropopliteal Peripheral Artery Disease

BACKGROUND

No adequately powered studies exist to compare major clinical outcomes after endovascular therapy (EVT) with stent implantation vs bypass surgery (BSx) for symptomatic femoropopliteal peripheral artery disease.

OBJECTIVES

This study sought to perform a pooled analysis of individual patient data from all randomized controlled trials comparing EVT vs BSx.

METHODS

Principal investigators of 5 of 6 available randomized controlled trials agreed to pool individual patient data. The primary endpoint was major adverse limb events, a composite of all-cause death, major amputation, or target limb reintervention. Secondary endpoints included amputation-free survival, individual major adverse limb event components, and primary patency. Early complications were bleeding, infection, or all-cause death within 30 days.

RESULTS

A total of 639 patients were analyzed with a mean age of 68.1 ± 9.1 years and 29.0% women. Baseline characteristics were comparable between groups. At 2 years, there were no significant differences between patients who received EVT and those who received BSx regarding major adverse limb events (40.1% vs 36.4%; log-rank P = 0.447; adjusted HR [aHR]: 1.04; 95% CI: 0.80-1.36), amputation-free survival (88.1% vs 90.0%; log-rank P = 0.455; aHR for death or amputation: 1.04; 95% CI: 0.63-1.71) and the other secondary endpoints except for primary patency, which was lower in patients who received EVT vs those who received BSx (51.2% vs 61.3%; log-rank P = 0.024; aHR for loss of primary patency: 1.31; 95% CI: 1.02-1.69). EVT was associated with significantly lower rates of early complications (6.8% vs 22.6%; P < 0.001) and shorter hospital stay (3.1 ± 4.2 days vs 7.4 ± 4.9 days; P < 0.001).

CONCLUSIONS

These findings further support the efficacy and safety of EVT as an alternative to BSx in patients with symptomatic femoropopliteal peripheral artery disease.

Strategies to counteract adverse remodeling of vascular graft: A 3D view of current graft innovations

Vascular grafts are widely used for vascular surgeries, to bypass a diseased artery or function as a vascular access for hemodialysis. Bioengineered or tissue-engineered vascular grafts have long been envisioned to take the place of bioinert synthetic grafts and even vein grafts under certain clinical circumstances. However, host responses to a graft device induce adverse remodeling, to varied degrees depending on the graft property and host's developmental and health conditions. This in turn leads to invention or failure. Herein, we have mapped out the relationship between the design constraints and outcomes for vascular grafts, by analyzing impairment factors involved in the adverse graft remodeling. Strategies to tackle these impairment factors and counteract adverse healing are then summarized by outlining the research landscape of graft innovations in three dimensions-cell technology, scaffold technology and graft translation. Such a comprehensive view of cell and scaffold technological innovations in the translational context may benefit the future advancements in vascular grafts. From this perspective, we conclude the review with recommendations for future design endeavors.

Long term clinical and functional venous outcomes after endovascular transvenous femoro-popliteal bypass

BACKGROUND

Peripheral artery disease is widespread in Western societies affecting around 13% of the population above 50 years of age. Despite recent improvements of endovascular treatment, open surgical bypass is still recommended as the treatment of choice for long segment TASC D lesions. The DETOUR procedure was introduced as an endovascular alternative in cases of long-segment superficial femoral artery occlusion. This unconventional technique raises several questions regarding the effect of the bypass graft on femoral venous physiology.

METHODS

We conducted a 3-year follow-up study of subjects enrolled and treated in the prospective, multicenter DETOUR study at the Pauls Stradins clinical university hospital, Riga, Latvia. In total, 52 consecutive patients (54 procedures) were enrolled in this study from 2015 until 2019. We performed Venous Clinical Severity Score (VCSS) and Villalta (VS) Score assessments, Duplex ultrasound measuring femoral and popliteal vein diameters, venous occlusion plethysmography and digital photoplethysmography to assess and compare venous physiology at baseline and at follow-up visits every 6 months.

RESULTS

At baseline mean femoral vein diameter was 11.1 mm (SD=1.5). At 36-months following intraluminal stent-graft placement, mean femoral vein diameter was 11.1 mm (SD=1.7) with no evidence of enlargement of the femoral vein (P=0.2). Popliteal vein diameter was not significantly changed during 24-months of follow-up (P=0.12) but showed a small (0.02 mm) statistically significant decrease in diameter at 36-months compared to baseline. During the study period, only one patient (1.9%) developed clinically significant ipsilateral DVT 1-month after surgery. Clinically silent femoral venous thrombosis was documented in 8 legs during 36-month follow-up. In one case the thrombus was occlusive and in 7 cases the thrombus was non-occlusive. At baseline, 48 of 52 patients (92%) had no or minor venous symptoms ([VCSS 0-2] with clinically significant venous symptoms in only 4 patients [VCSS≥3]). At one-month follow-up, the venous clinical severity score increased in all patients compared to baseline. At 6-month follow-up, the VCSS had returned to baseline in the majority of patients with no significant changes during the 3-year follow-up period. At baseline, all patients had a VS of 0-2 indicating minor or no venous symptoms (mean 0.4 [SD 0.7]). At the 1-month follow-up visit 3 patients (5.8%) had a VS≥3 (two patients had a score of 3 and one patient a score of 4), indicating significant venous symptoms. At the 6-month visit and thereafter, all the VS in all patients had returned to baseline. Transvenous endovascular procedure did not significantly alter venous physiology in treated leg.

CONCLUSIONS

Percutaneous transvenous femoropopliteal bypass provided safe and effective lower-extremity revascularization with minimal effect on long-term venous function. The femoral and popliteal vein remained patent with no compensatory enlargement in response to the presence of the bypass graft within the femoral vein. During 3-year follow-up there were no significant changes in venous symptom scores or physiologic function.

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.

Safety and feasibility study of non-invasive robot-assisted high-intensity focused ultrasound therapy for the treatment of atherosclerotic plaques in the femoral artery: protocol for a pilot study

INTRODUCTION

Peripheral arterial disease (PAD) is an atherosclerotic disease leading to stenosis and/or occlusion of the arterial circulation of the lower extremities. The currently available revascularisation methods have an acceptable initial success rate, but the long-term patency is limited, while surgical revascularisation is associated with a relatively high perioperative risk. This urges the need for development of less invasive and more effective treatment modalities. This protocol article describes a study investigating a new non-invasive technique that uses robot assisted high-intensity focused ultrasound (HIFU) to treat atherosclerosis in the femoral artery.

METHODS AND ANALYSIS

A pilot study is currently performed in 15 symptomatic patients with PAD with a significant stenosis in the common femoral and/or proximal superficial femoral artery. All patients will be treated with the dual-mode ultrasound array system to deliver imaging-guided HIFU to the atherosclerotic plaque. Safety and feasibility are the primary objectives assessed by the technical feasibility of this therapy and the 30-day major complication rate as primary endpoints. Secondary endpoints are angiographic and clinical success and quality of life.

ETHICS AND DISSEMINATION

Ethical approval for this study was obtained in 2019 from the Medical Ethics Committee of the University Medical Center Utrecht, the Netherlands. Data will be presented at national and international conferences and published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NL7564.

A Single-Center Study on the Outcomes of Target Limb Revascularization in Femoropopliteal Lesions Treated With Drug Coated Balloons and Bare Metal Stents

Purpose:

Multiple randomized controlled trials have shown that both drug coated balloons (DCBs) and bare metal stents (BMSs) significantly reduce restenosis in femoropopliteal lesions compared with plain balloon angioplasty. However, few studies have directly compared DCB and BMS treatments. Therefore, the goal of our study was to determine if the rate of target lesion revascularization (TLR) differs between DCB and BMS treatment at our center.

Materials and methods:

We performed a retrospective chart review of femoropopliteal interventions at a single center from 2009 to 2017. The intervention, patient and lesion characteristics, and TLR events were recorded. Exclusion criteria were loss of follow-up, death, bail-out stenting, and amputation within 60 days of treatment. Freedom from TLR was analyzed over a 3 year period with Kaplan-Meier survival curves. Cox hazard ratios were calculated to account for patient and lesion characteristics.

Results:

A total of 322 lesions (234 patients) treated with DCBs and 225 lesions (194 patients) treated with BMSs were included in this study. There were significant differences in baseline patient and lesion characteristics between groups—a greater proportion of women, patients with dyslipidemia, and lesions with popliteal involvement were treated with DCBs. There was no difference in the freedom from TLR between DCBs and BMSs. Accounting for patient and lesion characteristics, there was still no difference between DCBs and BMSs on the hazard of TLR. While our analysis did not detect a difference in the rate of TLR, there was a significant difference in the type of TLR. Compared with DCBs, a greater proportion of lesions initially treated with BMSs were retreated via surgical bypass rather than endovascular intervention, suggesting that lesions treated with DCBs may be more amenable to future endovascular intervention.

Conclusion:

Our retrospective analysis showed no difference in the rate of TLR between lesions treated with DCBs and BMSs. However, DCBs were more often used in complicated lesions involving popliteal arteries and may also allow for easier endovascular reintervention.

Clinical Outcome of Drug-Eluted Stenting (Zilver PTX) in Patients With Femoropopliteal Occlusive Disease a Single Center Experience

BACKGROUND

Few industry sponsored trials reported satisfactory outcomes in the use of drug-eluting stents (DES) for treatment of femoropopliteal arterial disease. This study analyzed the early/late clinical outcome from a real world single center.

PATIENT POPULATIONS/METHODS

A total of 115 limbs treated with Zilver PTX were analyzed for: major adverse limb event (MALE: above ankle limb amputation/major intervention at 1 year), major adverse events (MAEs; death, amputation, and target lesion thrombosis/reintervention), primary patency (based on duplex ultrasound ± ankle brachial indexes), limb salvage, and amputation free survival rates (AFS) at 1 and 2 years.

RESULTS

Indications included claudication in 32% and critical limb threatening ischemia (CLTI) in 68%. Lesions treated included: superficial femoral artery (SFA) 66%, both SFA and popliteal artery (PA) 19% and PA 15%. Mean lesion length was 21 cm and 68% had total occlusion. 45% were Trans-Atlantic Inter-Society Consensus (TASC) TASC II D lesions and 55% A-C lesions. Mean follow-up was 18.4 months (1-76 months). Perioperative major morbidity rate was 8.7% with 0% mortality. MALE rate at 1 year was 17% (13.5% for claudication vs 19.2% for CLTI, p=0.4499). MAE rate was 30% for claudication versus 52% for CLTI (p=0.0392). Overall primary patency rates at 1 and 2 years were 75% and 54% (86% and 71% for claudication vs 70% and 46% for CLTI, respectively, p=0.0213). Primary patency rates at 1 and 2 years were 94% and 88% for TASC A-C lesions versus 50% and 16% for TASC D lesions (p<0.0001). Overall freedom from MALE rate at 1 and 2 years were 85% and 79% (86% and 86% for claudication vs 84% and 74% for CLTI, p=0.2391). These rates were 96% and 93% for TASC A-C lesions versus 70% and 50% for D lesions, respectively (p<0.0001). Limb salvage rates at 1 and 2 years were 93% and 86% (100% and 100% for claudication vs 89% and 78% for CLTI, p=0.012). Overall AFS rates at 1 and 2 years were 79% and 71% (93% and 82% for TASC A-C vs 59% and 59% for D lesions, p=0.001).

CONCLUSION

Clinical outcomes after DES (Zilver PTX) in femoropopliteal arterial lesions were satisfactory for TASC A-C lesions but inferior/unsatisfactory for TASC D lesions.

[Are there alternatives to dual antiplatelet therapy after stenting of peripheral arteries?]

It is estimated that more than 200 million people worldwide suffer peripheral artery disease and the rate of amputations remains at a high level. The basis of treatment is timely revascularization wherein the fraction of interventions performed endovascularly has steadily been growing both in Russia and abroad. Nevertheless, the parameters of long-term patency of endovascular reconstructions of the infrainguinal segment are still inferior to open interventions. In order to select an optimal method of revascularization and to predict the duration of patency of the reconstruction modern clinical guidelines suggest using the GLASS and WIfI scales, which may improve the remote results of the intervention. Moreover, modern paclitaxel-coated stents and balloons may help increase primary patency of the reconstruction after endovascular procedures. A not less important method of improving remote results of endovascular treatment of patients with peripheral artery disease is considered to be the use of contemporary regimens of antithrombotic therapy. The VOYAGER PAD trial showed that in patients with peripheral artery disease after endured revascularization of lower limbs rivaroxaban prescribed at a dose of 2.5 mg twice daily in a combination with conventional antithrombocytic therapy made it possible to decrease the risk of such ischaemic complications as acute limb ischaemia, major amputation, myocardial infarction, ischaemic stroke and death of cardiovascular causes.

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.

Use of drug-eluting stents in patients with critical limb ischemia and infrapopliteal arterial disease: a real-world single-center experience

BACKGROUND

Although no drug-eluting stent (DES) has been approved by the Food and Drug Administration to treat infrapopliteal arterial disease, several industry-sponsored trials have reported the outcomes with the use of paclitaxel or sirolimus DESs. To the best of our knowledge, only one study to date has reported on the use of everolimus DESs for infrapopliteal arterial disease. In the present study, we analyzed the clinical outcomes with everolimus DESs in our real-world, single-center experience.

METHODS

A total of 107 limbs with critical limb threatening ischemia (98 patients; 118 lesions) treated with DESs (Xience; Abbott Vascular, Santa Clara, Calif) were analyzed. The postoperative early outcomes, major adverse limb events (above the ankle limb amputation or major intervention at 1 year), and major adverse events (death, amputation, target lesion thrombosis or reintervention) were analyzed. Kaplan-Meier analysis was used to estimate the primary patency rates (using duplex ultrasound), amputation-free rates, and amputation-free survival rates.

RESULTS

Of the 118 lesions treated, 33% were in the anterior tibial artery, 28% were in the tibioperoneal (TP) artery, 21% were in the posterior tibial artery, 8% were in the peroneal artery, 5% were in the TP/posterior tibial artery, 4% were in the TP artery/PA, and 1% were in the TP/anterior tibial artery. The mean lesion length was 41 mm, and 59% were totally occluded (41% stenotic). The mean follow-up was 18.5 months (range, 1-70 months). The overall postoperative complication rate was 11% (2% major amputations), with 2% mortality. Late symptom improvement of one or more Rutherford category was obtained in 71%. The major adverse events rate at 30 days and 1 year was 12% and 45%, respectively. The major adverse limb events rate at 1 year was 15%. The overall primary patency rate was 42%. The primary patency rate at 1, 2, and 3 years was 57%, 45%, and 33%, respectively. The major amputation-free and overall amputation-free survival rates were 87%, 80%, and 77% and 76%, 65%, and 61% at 1, 2, and 3 years, respectively.

CONCLUSIONS

The clinical outcomes after DES (Xience; Abbott Vascular) for infrapopliteal lesions were somewhat satisfactory at 1 year but inferior to the previously reported outcomes, especially at 3 years. Further data with long-term follow-up are needed.

Intravascular Application of Labelled Cell Spheroids: An Approach for Ischemic Peripheral Artery Disease

Mesenchymal stem cells (MSC) are known for their vascular regeneration capacity by neoangiogenesis. Even though, several delivery approaches exist, particularly in the case of intravascular delivery, only limited number of cells reach the targeted tissue and are not able to remain on site. Applicated cells exhibit poor survival accompanied with a loss of functionality. Moreover, cell application techniques lead to cell death and impede the overall MSC function and survival. 3D cell spheroids mimic the physiological microenvironment, thus, overcoming these limitations. Therefore, in this study we aimed to evaluate and assess the feasibility of 3D MSCs spheroids for endovascular application, for treatment of ischemic peripheral vascular pathologies. Multicellular 3D MSC spheroids were generated at different cell seeding densities, labelled with ultra-small particles of iron oxide (USPIO) and investigated in vitro in terms of morphology, size distribution, mechanical stability as well as ex vivo with magnetic resonance imaging (MRI) to assess their trackability and distribution. Generated 3D spheroids were stable, viable, maintained stem cell phenotype and were easily trackable and visualized via MRI. MSC 3D spheroids are suitable candidates for endovascular delivery approaches in the context of ischemic peripheral vascular pathologies.

Baseline local hemodynamics as predictor of lumen remodeling at 1-year follow-up in stented superficial femoral arteries

In-stent restenosis (ISR) is the major drawback of superficial femoral artery (SFA) stenting. Abnormal hemodynamics after stent implantation seems to promote the development of ISR. Accordingly, this study aims to investigate the impact of local hemodynamics on lumen remodeling in human stented SFA lesions. Ten SFA models were reconstructed at 1-week and 1-year follow-up from computed tomography images. Patient-specific computational fluid dynamics simulations were performed to relate the local hemodynamics at 1-week, expressed in terms of time-averaged wall shear stress (TAWSS), oscillatory shear index and relative residence time, with the lumen remodeling at 1-year, quantified as the change of lumen area between 1-week and 1-year. The TAWSS was negatively associated with the lumen area change (ρ = - 0.75, p = 0.013). The surface area exposed to low TAWSS was positively correlated with the lumen area change (ρ = 0.69, p = 0.026). No significant correlations were present between the other hemodynamic descriptors and lumen area change. The low TAWSS was the best predictive marker of lumen remodeling (positive predictive value of 44.8%). Moreover, stent length and overlapping were predictor of ISR at follow-up. Despite the limited number of analyzed lesions, the overall findings suggest an association between abnormal patterns of WSS after stenting and lumen remodeling.

[Modern strategy to improve remote results of surgical treatment of peripheral artery disease]

Treatment of patients presenting with peripheral artery disease requires a comprehensive approach: correction of risk factors, drug therapy and, if necessary, an endovascular/hybrid/open intervention. Reconstructive operation may effectively improve a patient's quality of life in intermittent claudication, save the limb and life in case of severe ischaemia. Discussed in the article are advantages and disadvantages of various types of surgical interventions for peripheral artery disease, the concept PLAN (Patient risk, Limb severity, and ANatomic complexity) and the new Global Anatomic Staging System (GLASS). Good remote results may be ensured by adequate medicamentous therapy. Variations of antithrombotic therapy are versatile and debatable. Long-term dual antithrombotic or systemic anticoagulant therapy with administration of vitamin K antagonists are not indicated for peripheral artery disease. In this connection, the findings of the COMPASS and VOYAGER PAD studies are analysed. The VOYAGER PAD trial showed that in patients with peripheral artery disease who underwent revascularization of lower limbs, the addition of rivaroxaban at a dose of 2.5 mg twice daily to aspirin decreased the risk of lower-extremity unfavourable ischaemic events and major adverse cardiovascular events by 15%. The obtained findings open new possibilities of conservative therapy having a significant role in decreasing the risk for development of limb-threatening conditions.

Endovascular treatment for chronic total occlusion of superficial femoral artery: Is retrograde approach from popliteal artery effective and safe?

A 55-year-old male was admitted with numbness in the left foot and intermittent claudication. Doppler ultrasound and digital subtraction angiography presented chronic total occlusion in the ostial of left superficial femoral artery and reperfusion flow at one-third below from collateral channels of deep femoral artery. Thus, we decided to perform an endovascular intervention for this patient. First, we used contralateral transfemoral approach technique, but the microwire could not reach to the occluded superficial femoral artery lesion. Then, we approached the chronic total occlusion lesion retrogradely. A wire was passed successfully from the popliteal artery to ostial superficial femoral artery. Finally, 2 stents were implanted. This case highlights that popliteal retrograde approach is effective and safe for total occlusion of superficial femoral artery.

Comparison of paclitaxel-coated balloon angioplasty with femoropopliteal bypass surgery in treating femoropopliteal lesions

OBJECTIVE

To compare drug (paclitaxel)-coated balloon angioplasty with femoropopliteal bypass surgery in the treatment of femoropopliteal lesions.

METHODS

A retrospective study was performed between January 2015 and January 2019, covering a four-year period. All subjects who underwent femoropopliteal bypass surgery and drug-coated balloon angioplasty over a four-year period were evaluated. The subjects' demographic characteristics, lesion characteristics, treatment outcomes and disease-free survival were collected. Subjects were divided into the femoropopliteal bypass group (Group A) and the drug-coated balloon angioplasty (Group B) group.

RESULTS

In total, 220 subjects were enrolled. Both Group A and Group B consisted of 110 subjects. The proportion of patients with a claudication distance between 0 and 50 m was significantly higher in Group A, and the proportion of patients with a claudication distance between 50 and 100 m was significantly higher in Group B (p = 0.001). In terms of the Rutherford levels, moderate claudication was significantly higher in Group B, and severe claudication was significantly higher in Group A (p = 0.001). The lesion length for the subjects in Group A was significantly longer than that in Group B (24.61 ± 2.79 mm for Group A and 18.59 ± 3.95 mm for Group B, p = 0.001). The stenosis degree in Group A was also significantly higher than that in Group B (96.82 ± 4.32% for Group A and 94.85 ± 4.55% for Group B, p = 0.001). The duration of the procedure, duration of hospitalization and rate of bleeding in Group A were significantly higher than those in Group B. The incidence of overall morbidity and reintervention rates in Group B were significantly higher than that in Group A. The preoperative ankle brachial index values of the subjects in Group B were statistically significantly higher than those in Group A (0.56 ± 0.08 for Group A and 0.61 ± 0.08 for Group B, p = 0.001). The change in the ankle brachial index measurement of the subjects in Group A with respect to the preprocedure value was significantly greater than that in Group B (p = 0.001). For primary patency, there was a significant difference between the groups in the distribution of the duplex ultrasound results at the 3rd, 6th, 9th and 12th month control points (p = 0.001). At all control points, Group A had better primary patency rates, whereas the secondary patency rates did not differ. In total, among the 220 patients, 125 (56.8%) were disease free, and 95 (43.2%) experienced recurrence. The mean disease-free survival times for Group A and Group B were 10.45 ± 0.28 months and 9.11 ± 0.37 months, respectively. The disease-free survival rates were significantly higher in Group A (p = 0.001, p < 0.05).

CONCLUSION

Femoropopliteal bypass resulted in better disease-free survival rates than drug-coated balloon angioplasty and serves as an effective modality for the treatment of femoropopliteal lesions.

In Situ Vein Bypass Is Superior to Endovascular Treatment of Femoropopliteal Lesions in Chronic Limb-Threatening Ischemia

BACKGROUND

The objective of the study was to compare bypass surgery and endovascular revascularization of the femoropopliteal segment in patients with peripheral arterial disease and critical limb-threatening ischemia (CLTI).

METHODS

This is a single-center study including patients undergoing first-time lower extremity intervention with peripheral bypass surgery or percutaneous transluminal angioplasty with or without stenting (PTA/S) of the femoropopliteal segment because of CLTI from 2011 to 2015. Based on prospective entered data from the Danish Vascular Registry, the primary end points were amputation-free survival, overall mortality, and reinterventions.

RESULTS

A total of 679 patients with CLTI were included of which 35% (n = 239) were treated with PTA/S, 54% (n = 363) with vein bypass, and 11% (n = 77) with synthetic bypass. After 3 years, amputation-free survival was significantly better with a vein bypass (41.8% [95% CI: 35-48.4]) than both PTA/S (29.7% (95% CI: 22.7-37)) and synthetic bypass (31.7% [95% CI: 19-45.1]). Overall, the endovascular-treated patients faced more than 50% increased risk of major amputation or death than that of a vein bypass, after adjusting for comorbidity and Trans-Atlantic Inter-Society Consensus (TASC) classification (HR: 1.56 [95% CI: 1.21-2.05]). As expected, postoperative complications, length of hospital stay, and reinterventions were more frequent in the bypass groups.

CONCLUSIONS

In this nonrandomized study, autologous vein bypass was superior to both PTA/S and synthetic bypass in regard to amputation-free survival and overall mortality. Despite the increased frequency of surgical complications, a vein bypass appears justified in both shorter (TASC B-C) and longer (TASC D) femoropopliteal lesions.

Bacterial cellulose biopolymer film and gel dressing for the treatment of ischemic wounds after lower limb revascularization

OBJECTIVE

to evaluate the use of a bacterial cellulose biopolymer film and gel dressing in the treatment of patients with ischemic wounds submitted to lower limb revascularization.

METHODS

we conducted a randomized clinical trial in the Angiology and Vascular Surgery outpatient clinic of the Clinics Hospital of the Federal University of Pernambuco, between January 2017 and December 2018. We followed 24 patients after lower limb revascularization, divided into two groups: Experimental, treated with bacterial cellulose biopolymer film and gel, and Control, treated with essential fatty acids. Patients attended weekly appointments to change dressings and had their wound healing processes evaluated over a period of 90 days.

RESULTS

the reduction of the ischemic wounds' areas after 30 days was 4.3cm2 (55%) on average for the experimental group, and the 5.5cm2 (48.5%) for the control group (p>0.05). The complete healing rate at 90 days was 34.8%, 50% in the experimental group and 18.2% in the control group (p=0.053).

CONCLUSION

the bacterial cellulose biopolymer film associated with gel can be used as a dressing in the treatment of ischemic wounds of patients undergoing revascularization of the lower limbs.

Clinical outcome of drug-coated balloon angioplasty in patients with femoropopliteal disease: A real-world single-center experience

BACKGROUND

Several multicenter industry-sponsored clinical trials reported satisfactory results in the use of drug-coated balloons (DCBs) for treatment of femoropopliteal occlusive disease. However, few single-center studies have been published to verify the outcome from real-world experience.

METHODS

In this study, 228 patients treated with DCB angioplasty (Lutonix 0.35; Bard, Tempe, Arizona) were analyzed. Perioperative major adverse events (death, amputation, target lesion thrombosis or reintervention) were calculated. Kaplan-Meier analysis was used to estimate primary patency rates (based on duplex ultrasound with or without ankle-brachial index) and limb salvage rates.

RESULTS

Lesions treated were primarily TransAtlantic Inter-Society Consensus (TASC) type C and D lesions. Indications included claudication (Rutherford classes 2 and 3) in 40% and critical limb ischemia (CLI; Rutherford classes 4 and 5) in 60%. Lesions treated included 61% in the superficial femoral artery, 15% in the popliteal artery, and 24% in both superficial femoral artery and popliteal artery. Mean follow-up was 12.2 months (range, 1-42 months). Overall perioperative morbidity and mortality rates were 13% and 1%. The perioperative major adverse event rate was 3%. Symptom relief (improvement of one Rutherford category or more) was obtained in 64%. Primary patency rates were 56% and 39% at 1 year and 2 years, respectively. Limb salvage rates were 92% and 83% at 1 year and 2 years. Patients with claudication had a lower rate of early perioperative complications (4% vs 19%; P = .001). Symptom improvement was 76% for claudication vs 49% for CLI (P < .001). Overall, major amputation rate was 0% for claudication vs 13% for CLI (P < .001). The primary patency rates at 1 year and 2 years were 59% and 41% for claudication vs 54% and 37% for CLI (P = .307). The assisted primary patency rates at 1 year and 2 years were 72% and 52% for claudication vs 64% and 46% for CLI (P = .223). Primary patency rates at 1 year and 2 years were 82% and 71% for TASC A to C lesions vs 29% and 14% for TASC D lesions (P < .001). Limb salvage rates at 1 year and 2 years were 100% and 100% for claudication vs 85% and 74% for CLI (P < .001).

CONCLUSIONS

Clinical outcomes after DCB angioplasty in femoropopliteal lesions were inferior to what has been reported in previous studies, particularly for TASC D lesions. Further investigation from real-world experience with long-term follow-up is needed to confirm these results.

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.

Nitinol Self-Expanding Stents for the Treatment of Obstructive Superficial Femoral Artery Disease: Three-Year Results of the RELIABLE Japanese Multicenter Study

Objective: To assess the use of a nitinol stent to treat symptomatic stenoses or occlusions of the native superficial femoral artery (SFA).

Materials and Methods: Seventy-four patients were treated at 12 Japanese sites. The primary endpoint, freedom from target-limb failure (TLF), was a composite of device- or procedure-related death, target-limb amputation, target-vessel revascularization (TVR), or restenosis compared to an objective performance goal (OPG) at 12 months. Secondary endpoints, including primary patency, freedom from TVR/target-lesion revascularization (TLR), improvements in clinical parameters, and major adverse events (MAEs) were evaluated through 36 months.

Results: The mean overall lesion length was 80.7±38.9 mm (mean stented length: 98.8±46.1 mm). Freedom from TLF was 81.2% (p<0.001 compared to OPG) with a Kaplan–Meier estimate of 84.2% [95% confidence interval (95%CI) 73.3%, 90.9%] at 12 months. Primary patency was 71.0% at 12 months and 67.8% at 36 months. A total of 94.7% of patients improved by at least one Rutherford category and 70.2% of patients improved ankle–brachial indices ≧0.10 from baseline to 36 months. Freedom from TVR/TLR (Kaplan–Meier) was 90% at 12 months and 79.5% at 36 months. Four MAEs were reported; none were found to be device or procedure related.

Conclusion: A self-expanding stent was used safely to treat stenotic and occlusive lesions of the SFA in a Japanese patient population. The composite endpoint, freedom from TLF, was superior to an historical control at one year, with low rates of revascularization and good functional and clinical outcomes through three years.