Outback catheter for femoropopliteal occlusions: immediate and long-term results

Recanalization of Chronic Femoropopliteal Total Occlusions after Failed Anterograde Attempt: Use of an Intravascular Ultrasound-Guided Re-entry Catheter versus the Bidirectional Approach

PURPOSE

To analyze the feasibility and effectiveness of the use of an intravascular ultrasound (IVUS)-guided re-entry catheter (IGRC) for femoropopliteal chronic total occlusions (FP-CTOs) after a failed anterograde approach compared with the bidirectional approach without the IGRC.

MATERIALS AND METHODS

Between June 2019 and December 2022, an IGRC (Pioneer Plus; Philips Volcano, San Diego, California) was used in 52 patients after failure of conventional recanalization techniques (Group A). In the same period, 48 patients who were also eligible for IGRC use were treated without IGRC using the bidirectional approach (Group B). In Groups A and B, 12 (23.1%) and 3 (6.2%) patients experienced claudication, and 40 (76.9%) and 45 (93.7%) patients experienced critical limb-threatening ischemia, respectively. Clinical and procedural records, angiographic imaging findings, and follow-up data were collected, analyzed, and reviewed.

RESULTS

Technical success was achieved in 49 (94.2%) patients in Group A and 44 (91.7%) patients in Group B (P = .616). Use of the IGRC was associated with a reduction of procedural time (120 vs 133 minutes; P < .001), radiation exposure (47 vs 59 Gy cm2; P < .001), iodinated contrast medium use (98 vs 138 mL; P = .028), and intraprocedural discomfort (numerical rating scale score, 4 vs 6; P < .001).

CONCLUSIONS

Use of the IGRC was equivalently successful for FP-CTO recanalization compared with the use of the bidirectional approach, but it reduced radiation exposure, iodinated contrast medium used, patient discomfort, and procedural time. These advantages suggest that IGRC could be favored as the next-choice option for FP-CTOs after failure of anterograde recanalization.

Peripheral Arterial Disease: A Narrative Review

Peripheral arterial disease (PAD) describes the partial or complete occlusion of blood flow in the distal arteries of the body. A decreased arterial patency may occur due to a reduction in the elasticity or diameter of the vessel. The goal of interventions is to decrease incidence and reduce complications by identifying and minimizing the primary causes. This paper discusses PAD affecting the aortoiliac, common femoral, and femoropopliteal arteries. In a significant portion of the population, PAD may lack usual symptoms such as limb pain, claudication, and diminished pulses. Imaging techniques become crucial to ensuring timely diagnosis, monitoring treatment effectiveness, and preventing recurrence. Duplex ultrasound (DUS) is a cheap and non-invasive preliminary technique to detect atherosclerotic plaques and grade arterial stenosis. Magnetic resonance angiography (MRA) provides the added advantage of minimizing artifacts. Digital subtraction angiography (DSA) remains the gold standard for grading the degree of stenosis but is only employed second-line to DUS or MRA due to the high dose of nephrotoxic contrast. Computed tomography angiography (CTA) is able to overcome the anatomical limitations of DUS and MRA and proves to be a suitable alternative to DSA in patients with renal disease. Preventative measures involve monitoring blood pressure, cholesterol levels, and tobacco usage. First-line treatment options include endovascular procedures as well as surgical interventions in cases of significant arterial involvement. Endovascular treatments involve the use of balloon angioplasty, drug-coated balloons, and drug-coated stents, to name a few, that serve as minimally invasive techniques to manage PAD. Surgical procedures, although more complex, are considered gold-standard treatment options for long and intricate lesions. Endovascular methods are generally preferred over surgical options as the complication risk is severely reduced and the rates of reintervention are comparable to surgical options.

Success rate of endovascular recanalization for femoropopliteal artery total occlusion using the wingman catheter system

Chronic total occlusion (CTO) in the femoropopliteal artery is challenging to treat. The Wingman catheter system is a novel device for CTO penetration with a nitinol/stainless steel beveled tip. There is a lack of real-world clinical data indicating the success rate. We evaluated the efficacy of the Wingman system. This was a single-center retrospective study. We enrolled 27 consecutives patients who underwent treatment for femoropopliteal CTO using the Wingman system in 2021. The primary outcome was success of CTO-crossing and secondary outcomes were success of the procedure, Wingman-related complications, and predictors for success of Wingman crossing. The mean age of the study population was 76 years and the mean CTO length was 122 mm. The success rate of Wingman crossing was 40.7% and the overall procedure success rate was 100%. Only one case of embolism and one of perforation associated with the Wingman procedure were seen; both were successfully recovered. Univariate analysis revealed in-stent occlusion and non-severe calcification to be factors associated with success (16.7% vs 0%, p = 0.012 and 12.5% vs 50.0%, p = 0.036, respectively). These real-world data of the Wingman system demonstrate it to be a safe and one of option for treating femoropopliteal CTO.

Medial artery calcification in peripheral artery disease

Medial artery calcification (MAC) is a distinct, highly regulated process that is often identified in small and mid-sized arteries of the lower extremities. It is associated with advanced age, diabetes, and chronic kidney disease. MAC often occurs in conjunction with atherosclerotic occlusive disease in lower extremity arteries, and when seen together or in isolation, long-term limb outcomes are negatively affected. In patients with peripheral artery disease (PAD), the extent of MAC independently correlates with major amputation and mortality rates, and it predicts poor outcomes after endovascular interventions. It is associated with increased arterial stiffness and decreased pedal perfusion. New endovascular methods aimed at treating calcified lower-extremity lesions may improve our ability to treat patients with limb-threatening ischemia. Although recent developments have increased our understanding of the mechanisms contributing to MAC, further investigations are needed to understand the role of medial calcification in PAD, and to develop strategies aimed at improving patient outcomes.

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.

Open Proximal Endarterectomy with Retrograde Access and Stenting: A Novel Technique for Lower Extremity Revascularization

BACKGROUND

Treatment of chronic limb threatening ischemia (CLTI) poses a significant clinical challenge despite recent medical advancements. Chronic total occlusion (CTO) lesions make endovascular approaches to CLTI particularly challenging. Open proximal exposure with retrograde access and stenting (OPERAS) aims to solve this challenge through retrograde subintimal crossing of a CTO with direct visualization of proximal re-entry into the true lumen. We describe this novel technique and present its efficacy in eight patients.

METHODS

We conducted a retrospective case series at a single tertiary academic center. Data for patients who received OPERAS intervention included demographics, peri-operative details, and follow-up information. Statistical analysis was performed on length of stay, major post-operative complications, further intervention, clinical progression at 1 year, and amputation-free survival at 1 year. Immediate technical failure (ITF) and limb-based patency (LBP) at 1 year were calculated.

RESULTS

Nine limbs underwent OPERAS between January 2019 and March 2020. Inflow was achieved with common femoral artery endarterectomy. All limbs underwent balloon angioplasty and stenting of the SFA, and seven underwent the same procedure in the popliteal artery. ITF was 0% for all nine cases. There were no major post-operative complications, and ankle-brachial index significantly improved pre-and post-operatively (P < .001). Eight limbs (88.9%) sustained amputation-free survival at 1 year, and overall LBP was 67% at 1 year.

CONCLUSION

Our study presents a hybrid revascularization option to address severe, anatomically complex limbs (GLASS III) that lack a single autogenous conduit for open surgical revascularization. OPERAS addresses a main point of technical failure of subintimal techniques by directly visualizing the wire in the true lumen. Our data suggest that OPERAS can be effective to: (1) improve technical success of luminal re-entry following a subintimal approach; (2) address inflow concurrently with severe femoropopliteal disease; and (3) can be utilized when distal tissue loss is involved.

Treatment of atherosclerotic femoropopliteal artery disease with Supera interwoven nitinol stent: a real-world study in China

OBJECTIVES

To analyze the outcomes of Supera stent deployment in Chinese patients with atherosclerotic femoropopliteal artery (FPA) disease in a real-world setting.

METHODS

This retrospective cohort study collected and analyzed the medical records of 246 consecutive patients who received Supera stents for FPA disease at the China Academy of Chinese Medical Sciences Xiyuan Hospital between February 2017 and December 2019. All study patients underwent balloon angioplasty and were treated with Supera stents (Abbott Vascular, Santa Clara, CA, USA). The primary outcome was the rate of primary patency 12 months after discharge.

RESULTS

The analyses included 246 consecutive patients and 260 lesions. The mean ± SD age was 73.2±9.9 years and most patients (60.2%) were male. Of the 260 treated lesions, Supera stents were deployed in eight (3.1%) cases after previous stent fracture. Critical limb ischemia was diagnosed in 87.3% of the limbs, and 84 (32.3%) and 83 (31.5%) cases were classified as TransAtlantic Inter-Society Consensus (TASC) C and D, respectively. The majority of the lesions was in situ (80.8%) and located in the superficial femoral artery (45.0%) or the femoropopliteal artery (45.8%). The mean lesion length was 147.7 mm. Nominal deployment (-10% to 10% compression) was the most common deployment scenario (84.1%). The 1-year primary patency rate was 80.6%. Lesions that occurred as restenosis (OR = 3.34, 95% CI: 1.03-10.85, P = 0.045) or in-stent restenosis (OR = 2.88, 95% CI: 1.03-8.07, P = 0.045) were independently associated with occlusion or stenosis after stent deployment. No stent fracture was observed in the study.

CONCLUSIONS

Our study indicates that the use of Supera stents is feasible for treatment of Chinese patients with FPA disease. The long-term results reveal high primary patency.

First Experience With The GoBack-Catheter For Successful Crossing of Complex Chronic Total Occlusions in Lower Limb Arteries

PURPOSE

To evaluate the use of the GoBack-catheter (Upstream Peripheral Technologies) in complex revascularizations in lower limb arteries.

MATERIALS AND METHODS

In this retrospective single-center study, the results of the first 100 consecutive patients including 101 limb-revascularizations, performed between May 2018 and July 2020 with the study device, were analyzed. In all cases, guidewire-crossing failed, and all lesions were chronic total occlusions (CTO), either de novo, reocclusions, or in-stent reocclusions. Successful crossing was defined as passing the CTO using the study device. Patency at discharge and after 30 days was defined as less than 50% restenosis on duplex sonography, without target lesion revascularization.

RESULTS

Median lesion length was 24 cm and 38 patients (37.6%) had a calcium grading according to the peripheral arterial calcium scoring system (PACSS) of 4 or 5. In 20.8% of patients, an occluded stent was treated. CTOs involved the femoropopliteal segment in 91.1%, iliac arteries in 5.9%, and tibial arteries in 7.9%. The GoBack-catheter was employed for entering into or crossing through parts or the full length of a CTO or an occluded stent as well as for re-entering into the true lumen after subintimal crossing. The device was used via contralateral and ipsilateral antegrade as well as retrograde access with an overall technical success rate of 92.1%. In 3 patients minor bleeding occurred at the crossing or re-entry site, which were managed conservatively. Thirty-day adverse limb events comprised minor amputations in 4 patients (4.0%), 1 major amputation (1.0%), and reocclusions in 7 limbs (6.9%).

CONCLUSION

The new GoBack-catheter offers versatile endovascular applicability for complex CTO recanalization in a broad range of peripheral vascular interventions with a high technical success and low complication rate.

Device profile of the FLEX Vessel Prep System for the treatment of peripheral arterial disease: overview of its safety and efficacy

INTRODUCTION

The standard endovascular treatment for obstructed peripheral arterial disease (PAD) lesions and stenosed arteriovenous (AV) fistulae is percutaneous transluminal angioplasty (PTA). Despite consistent effectiveness in restoring blood flow, PTA does introduce risk of uncontrolled dissections that require stenting. The FLEX Vessel Prep™ System (FLEX VP) is a novel, dynamic, self-sizing, nonballoon device designed to modify obstructive stenoses and plaque, improve vessel compliance and facilitate delivery of drug therapies by creating longitudinal, controlled-depth, circumferential microincisions along the entire length of a lesion.

AREAS COVERED

In this profile, the mechanism of action of the FLEX VP system is described and differentiated. Acute procedural complications and long-term clinical outcomes following FLEX VP+PTA are presented. Specifically, the unmet clinical need for safe and effective vessel preparation in long, complex, mixed morphology PAD lesions is highlighted.

EXPERT OPINION

The FLEX VP system is an innovative approach to create predictable and consistent longitudinal microincisions in long lesions that improve acute luminal gain and vessel compliance by releasing circumferential tension in the lesion. This nonballoon-based device for plaque modification is safe, effective, easy-to-use, and minimizes PTA-associated dissections, therefore reducing stenting, supporting the 'leave nothing behind' incentive of physicians, and improving long-term clinical outcomes with less vessel trauma.

The "needle re-entry" technique for infrainguinal arterial calcified occlusive lesions

Background

Vascular calcification is a predictor of poor clinical outcome during and after endovascular intervention. Guidewire crossing techniques and devices have been developed, but chronic total occlusions (CTOs) with severe calcification often prevent subintimal re-entry. We propose a novel guidewire crossing approach combined needle rendezvous with balloon snare technique, named the “needle re-entry” technique, for treatment of complex occlusive lesions.

Main text

A 73-year-old female with severe claudication in her right calf with ankle brachial index of 0.62, and a computed tomography angiogram showed a long occlusion with diffuse calcification in superficial femoral artery. She was referred to our department to have peripheral interventions. Since the calcified vascular wall of the lesion prevented the successful re-entry, the “needle re-entry” was performed. First, a retrograde puncture of the SFA, distally to the occlusion, was performed and an 0.018-in. guidewire with a microcatheter was inserted to establish a retrograde fashion. Second, an antegrade 5.0-mm balloon was advanced into a subintimal plane and balloon dilation at 6 atm was maintained. Third, an 18-gauge needle was antegradely inserted from distal thigh to the dilated 5.0-mm balloon. After confirming a balloon rupture by the needle penetration, we continued to insert the needle to meet the retrograde guidewire tip. Then, a retrograde 0.014-in. guidewire was carefully advanced into the needle hole, named the “needle rendezvous” technique. After further guidewire advancement to accomplish a guidewire externalization, the needle was removed. Finally, since the guidewire was passing through the 5.0-mm ruptured balloon, the balloon was withdrawn, and the guidewire was caught with the balloon and successfully advanced into the antegrade subintimal space, named the “balloon snare” technique. After the guidewire was advanced into the antegrade guiding sheath and achieved a guidewire externalization, an endovascular stent graft and an interwoven stent were deployed to cover the lesion. After postballoon dilation, an angiography showed a satisfactory result without complications. No restenosis, reintervention, and limb loss have been observed for one year follow-up period after this technique.

Conclusions

The “needle re-entry” technique is a useful guidewire crossing technique to revascularize femoropopliteal complex CTOs with severe calcification which prevent the achievement of guidewire crossing with the conventional procedures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42155-021-00274-y.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

The "Pull, Cast, and Fix" Technique for Bypass in the Midpopliteal (P2) Arterial Segment in Chronic Femoropopliteal Occlusions

Femoropopliteal bypass operations can be difficult when the occlusive disease involves the superficial femoral artery and the popliteal arterial segment above the knee joint (supragenicular artery, P1). In case of lack of suitable vein graft or when the surgeon wishes to spare to infrapopliteal segment, the choice of the midpopliteal artery as anastomotic site becomes challenging because of its location. Moreover, totally endovascular recanalization procedures in such cases can be complex and demanding, whereas other reported hybrid revascularization techniques require advanced technical skills and raise significantly the cost. Therefore, we present our suggestion of a "pull, cast, and fix" technique to encounter these challenges and facilitate a successful bypass with a synthetic graft in the upper midpopliteal (P2) segment, combing a secure endarterectomy and anastomosis even under marginal visualization by means of securing the lumen with a soft feeding tube after the artery has been pulled via a Satinsky vascular clamp. Accordingly, the procedure is accomplished with placement of a flexible self-expandable stent in the midpopliteal artery through the synthetic graft.

Efficacy and Safety of a Novel Helical Self-Expanding Nitinol Stent for Femoropopliteal Artery Obliterans Disease

BACKGROUND

The aim of this study was to evaluate the efficacy and safety of a novel self-expanding nitinol stent (Smartflex stent) in femoropopliteal artery obliterans disease.

METHODS

From June 2016 to May 2019, patients with atherosclerotic occlusion disease of the superficial femoral and popliteal arteries using the Smartflex stents were retrospectively analyzed in our institution. Patients were monitored at 1, 3, 6, and 12 months and annually thereafter. The main characteristics of the diseased vessels, perioperative and follow-up outcome were evaluated. Kaplan-Meier method was used to assess patency rate and the rate of freedom from clinically driven target lesion revascularization (CD-TLR).

RESULTS

A total of 50 limbs from 48 patients (mean age 69.4 ± 8.95 years; 38 men) were included. Eighty-eight Smartflex stents (1.76 stents per limb) were deployed successfully. Of the study patients, 82% had claudication (Rutherford III), 10% had rest pain (Rutherford IV), and 8% had tissue loss (Rutherford V). Trans-Atlantic Inter-Society Consensus II C and D lesions were 26% and 42%, respectively. The mean lesion length was 18.2 ± 8.5 cm and the mean stented length was 22.3 ± 9.9 cm. The average follow-up time was 16.4 ± 8.2 months. Of these lesions, 42 (94%) were chronic total occlusions and 16 (32%) were severely calcified. The primary patency rate at 1 year per Kaplan-Meier estimating, the rate of freedom from CD-TLR at 1 year, and the second patency rate was 83.3%, 88.1%, and 94%, respectively. Among them, 90% patients had improved ankle-brachial indexes (0.47 ± 0.13 before and 0.84 ± 0.16 after). No stent fractures and kinking were identified.

CONCLUSIONS

Stenting of the femoropopliteal artery diseases using the Smartflex stent appeared to be safe and effective. It performed well in long-segment and above knee joint lesions.

Recent Update on Peripheral Arterial Endovascular Therapy for Peripheral Arterial Occlusive Disease

Endovascular treatment is effective for symptomatic peripheral arterial disease (PAD). Following recent device improvements, favorable long-term outcomes have been achieved in iliac arteries as well as small arteries such as the femoral and popliteal arteries.

This paper outlines the history and recent advances in endovascular treatment of peripheral vascular diseases as well as the characteristics and usage of devices. The history and the advances in endovascular treatment of peripheral vascular disease have been parallel, with the development of devices such as catheters and stents. Accordingly, endovascular treatment is now recommended in guidelines as the first-line for PAD.

A Novel Angiographic Risk Score for Femoropopliteal Interventions

PURPOSE

To present a novel angiographic scoring system that stratifies the risk of restenosis after endovascular therapy (EVT) to inform the decision to use paclitaxel-eluting devices in the femoropopliteal segment.

MATERIALS AND METHODS

A prospective, multicenter registry including 1799 limbs of 1578 patients (mean age 74±9 years; 1090 men) with symptomatic peripheral artery disease undergoing intravascular ultrasound-supported femoropopliteal EVT was used as the basis for developing the angiographic score. Multivariable analysis identified baseline patient and limb characteristics associated with restenosis at 12 months. These risk factors for 12-month restenosis were explored using a generalized linear mixed model with a logit-link function in which the inter-institutional and inter-subject variability were treated as random effects. The multiple imputation method was adopted to address missing data. Results of the regression analysis are presented as the odds ratio (OR) with 95% confidence interval (CI).

RESULTS

Twelve-month primary patency was estimated to be 65.1% (95% CI 62.7% to 67.5%). After multivariable analysis, distal reference vessel diameter per 1 mm (OR 0.71, 95% CI 0.62 to 0.81, p<0.001), lesion length per 10 cm (OR 1.39, 95% CI 1.19 to 1.62, p<0.001), and chronic total occlusion (OR 1.56, 95% CI 1.15 to 2.10, p=0.004) were independently associated with the 12-month restenosis risk, whereas baseline patient risk factors were not. Compared to bare nitinol stent implantation, plain angioplasty (OR 2.31, 95% CI 1.67 to 3.18, p<0.001) was independently associated with a higher risk of 12-month restenosis, while drug-eluting stents (OR 0.65, 95% CI 0.43 to 0.99, p=0.045) and stent-grafts (OR 0.24, 95% CI 0.12 to 0.50, p<0.001) were independently associated with a lower risk of 12-month restenosis. The angiographic score, which was developed by using the 3 angiographic factors but not the TransAtlantic Society Consensus II (TASC) class, was significantly and independently associated with 12-month restenosis.

CONCLUSION

The current study demonstrated a novel angiographic score for 12-month restenosis after femoropopliteal EVT in a real-world clinical practice. The developed score was significantly and independently associated with the 12-month restenosis risk, but the TASC class was not.

The creation of an endovascular exit through the vessel wall using a minimally invasive working channel in order to reach all human organs

Since the establishment of the Seldinger technique for secure entry to the vascular system, there has been a rapid evolution in imaging and catheters that has made the arteries and veins internal routes to any place in the body for interventions. It is curious that a general exit from the vasculature in a similar manner has not been proposed earlier. Possibly, the simplest reason is that accidental perforation of the vasculature by guide wire or catheter is a feared adverse event in endovascular intervention. Most places in the body can be reached by ultrasonography or computed tomography-guided intervention. Some organs such as the central nervous system, the heart and pancreas are harder to access and, in some organs, like the kidney, repeated percutaneous punctions to cover large areas is not suitable. We present a new general purpose micro-endovascular device creating a working channel to these 'hard to reach' organs by an inverted Seldinger technique. This review details this trans-vessel wall technique, which has been studied in pancreas for transplantation of insulin-producing cells, for injection of contrast agent to the heart and to the brain, bowels and kidney in rat, rabbit, swine and macaque monkeys with up to one year of follow-up without adverse events. Furthermore, the payloads that can be given through such a system are briefly discussed. Drugs, cells, gene vectors and other therapeutic substances may be injected directly to the tissue to increase efficacy and decrease risk of off-site adverse effects.

Adjunctive stent use during endovascular intervention to the femoropopliteal artery with drug coated balloons: Insights from the XLPAD registry

With growing use of drug-coated balloons (DCB) for femoropopliteal (FP) artery interventions, there is limited information on rates of real-world adjunctive stent use and its association with short and long-term outcomes. We report on 225 DCB treated FP lesions in 224 patients from the Excellence in Peripheral Artery Disease (XLPAD) registry (NCT01904851) between 2014 and 2016. Cochran–Mantel–Haenszel and Wilcoxon rank sum statistics were used to compare stented (planned or ‘bail-out’) versus non-stented DCB treated lesions. Stents were implanted in 31% of FP DCB interventions. Among the 70 stents implanted, 46% were for ‘bail-out’ indications and 54% were planned. Lesions treated with stents were longer (mean 150 mm vs 100 mm; p < 0.001) and less likely to be in-stent restenosis lesions (10% vs 28%; p=0.003). Stenting was significantly more frequent in complex FP lesions, including chronic total occlusions (66% vs 34%; p < 0.001). For bail-out stenting, interwoven nitinol stents were the most common type (50%) followed by drug-eluting stents (34%) and bare-metal stents (22%). There were no differences in peri-procedural complication rates or 12-month target limb revascularization rates (18.6% vs 11.6%; p=0.162) or 12-month amputation rates (11.4% vs 11%; p=0.92) between lesions where adjunctive stenting was used versus lesions without adjunctive stenting, respectively. In conclusion, in a contemporary ‘real-world’ adjudicated multicenter US registry, adjunctive stenting was necessary in nearly a third of the lesions, primarily for the treatment of more complex FP lesions, with similar short and intermediate-term clinical outcomes compared with non-stented lesions. ClinicalTrials.gov Identifier: NCT01904851

Endovascular Treatment of Severely Calcified Femoropopliteal Lesions Using the “Pave-and-Crack” Technique: Technical Description and 12-Month Results

Purpose: To report midterm results of the “pave-and-crack” technique to facilitate safe and effective scaffolding of heavily calcified femoropopliteal lesions in preparation for delivery of a Supera interwoven stent. Methods: Data were collected retrospectively on 67 consecutive patients (mean age 71±8 years; 54 men) treated with this technique between November 2011 and February 2017 at a single center. A third (22/64, 34%) of the patients had critical limb ischemia (CLI). Most lesions were TASC D (52/67, 78%), and the majority were occlusions (61/66, 92%). The mean lesion length was 26.9±11.2 cm. Nearly two-thirds (40/64, 62%) had grade 4 calcification (Peripheral Arterial Calcium Scoring System). To prepare for Supera stenting, the most heavily calcified segments of the lesion were predilated aggressively to obliterate recoil. A Viabahn stent-graft was then implanted to “pave” the lesion and protect from vessel rupture as aggressive predilation continued until the calcified plaque was “cracked” before lining the entire lesion with a Supera stent. Patency and target lesion revascularization (TLR) rates were estimated using the Kaplan-Meier method. Results: Procedural success was achieved in 100% and technical success (residual stenosis <30%) in 98% (66/67). The mean cumulative stent lengths were 16±9 cm for the Viabahn and 23±12 cm for the Supera. Only 2 complications occurred (distal embolization and access-site pseudoaneurysm). Two CLI patients died within 30 days, and 3 patients (all claudicants) underwent a TLR. Patients were followed for a mean 19±18 months, during which another 2 CLI patients died and 1 patient had a major amputation. One-year primary and secondary patency estimates were 79% and 91%, respectively; freedom from TLR was 85%. Conclusion: Despite severe lesion calcification, patients experienced high technical success and a safe and durable therapy at midterm follow-up with the femoropopliteal “pave-and-crack” technique.

Transvenous Intravascular Ultrasound-Guided Endovascular Treatment for Chronic Total Occlusion of the Infrainguinal Arteries

PURPOSE

To investigate the 1-year outcomes of transvenous intravascular ultrasound (IVUS)-guided endovascular therapy (EVT) for chronic total occlusion (CTO) of the lower extremity arteries.

METHODS

Transvenous IVUS-guided EVT was performed in 44 patients (50 limbs) with CTO of the femoropopliteal arteries or tibioperoneal trunk. Treatment involved crossing a guidewire through the CTO under the guidance of both fluoroscopic and IVUS imaging, along with insertion of the IVUS catheter into a vein parallel to the target artery. Primary success rate, complications, and target lesion revascularization (TLR) at 12-month follow-up were investigated.

RESULTS

Successful recanalization, defined as grade 3 flow (Thrombolysis in Myocardial Infarction score) and no flow-limiting dissection, was observed in 48 (96%) limbs. Two limbs with failed recanalization had a very long CTO lesion from the superficial femoral artery to below the knee. A bidirectional approach was selected in 11 (22%) limbs. Complications at the access site occurred in only 2 patients. The rate of freedom from TLR at 12 months was 77.9% (95% confidence interval 61.4 to 87.9).

CONCLUSION

Transvenous IVUS-guided EVT is safe and can provide optimal short-term results for EVT of CTO in the infrainguinal arteries. IVUS-guided EVT may be one of the most effective treatment strategies for CTO of the femoropopliteal arteries or tibioperoneal trunk.

Comparison of the OUTBACK® Elite Reentry Catheter and the Bi-directional Approach after Failed Antegrade Approach for Femoro-popliteal Occlusive Disease

Aim: A successful antegrade wire crossing for femoro-popliteal chronic total occlusion (FP-CTO) is still a technical challenge. We attempted to demonstrate the safety and feasibility of the OUTBACK^® Elite reentry catheter and the bi-directional approach for failed FP-CTO cases with the antegrade approach.

Methods: Endovascular therapy for FP-CTO was performed in 219 lesions from May 2013 to December 2016 at Morinomiya Hospital. We retrospectively analyzed the data of 43 consecutive lesions which underwent endovascular therapy using the bi-directional approach with distal access and the mono-directional approach with the OUTBACK^® Elite reentry catheter for FP-CTO lesions. The antegrade success using a combination of traditional and Intravascular Ultrasound (IVUS) -guided techniques was achieved in 170 lesions out of a total of 219 lesions. From May 2013 to June 2016 (phase 1), the bi-directional approach with distal access was applied to 22 lesions after failed antegrade approaches. From July 2016 to December 2016 (phase 2), the mono-directional approach with the OUTBACK^® Elite reentry catheter was applied to 21 lesions.

Results: Clinical and lesion characteristics in phase 1 were not significantly different from those in phase 2. The overall initial technical success rate was 100% in both phases. The total wire number and amount of contrast media were significantly less, and the total procedure time and the total fluoroscopic time were significantly shorter in phase 2 than in phase 1 (p < 0.01).

Conclusions: Endovascular therapy for FP-CTO using the OUTBACK^® Elite reentry catheter is feasible and safe after a failed antegrade approach.

[Subintimal recanalization. Indications, technique and results]

CLINICAL/METHODICAL ISSUE

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

STANDARD RADIOLOGICAL METHODS

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

METHODICAL INNOVATIONS

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

PERFORMANCE

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

ACHIEVEMENTS

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

PRACTICAL RECOMMENDATIONS

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

Midterm Patency After Femoropopliteal Interventions

Purpose: To describe and compare primary patency rates in patients undergoing endovascular femoropopliteal interventions with standard or interwoven nitinol stents or drug-coated balloons. Methods: A cohort of 1292 patients was treated for symptomatic femoropopliteal occlusive disease classified as Rutherford category ≥1 at a large vascular center between June 2006 and August 2013 using either standard nitinol stents (SNS; n=432), interwoven nitinol stents (INS; n=470), or drug-coated balloons (DCB; n=390). Primary patency rates were assessed by ultrasound or angiographic readings for over 3 years of follow-up. Propensity score–matched pairs were formed to compare each treatment with another using survival analysis. Results: Survival curves of primary patency favored INS compared with SNS in 368 propensity score–matched pairs (p<0.001). Kaplan-Meier estimates at 1, 2, and 3 years were 86.6%, 76.4%, and 68.9%, respectively, in the INS group vs 60.5%, 46.1%, and 42.1%, respectively, in the SNS group. No significant difference (p=0.232) was seen for the comparison of SNS vs DCB in 284 matched pairs over long-term follow-up (primary patency estimates at 1, 2, and 3 years were 79.8%, 53.8%, and 32.9%, respectively, in the DCB group vs 60.5%, 44.8%, and 40.3%, respectively, in the SNS group). Survival curves of primary patency favored INS over DCB in 254 matched pairs (p<0.001). Kaplan-Meier estimates at 1, 2, and 3 years were 79.0%, 51.2%, and 30.1%, respectively, in the DCB group vs 89.0%, 76.9%, and 66.2%, respectively, in the INS group. Conclusion: Propensity score–based analysis of primary patency suggests profound differences in restenosis rates between various treatment modalities for femoropopliteal disease for over 3 years of follow-up.

Targeted True Lumen Re-Entry With the Outback Catheter

Purpose: To report a single-center experience with the Outback re-entry device for targeted distal true lumen re-entry during subintimal recanalization of chronic total occlusions (CTOs) and compare the results with a systematic review of the literature. Methods: Between February 2011 and July 2013, 104 Outback devices were employed in 91 patients (mean age 64±9 years; 57 men) for subintimal recanalization of 100 vessels with CTOs after initial failure of spontaneous reentry. Fifty-two cases involved a retrograde approach to aortoiliac occlusions and 48 were re-entry attempts in infrainguinal CTOs. Outcome measures included complications and technical success, defined as successful targeted re-entry at the preplanned site of the distal true lumen. To evaluate device accuracy, the re-entry distance (between the point of true vessel reconstitution and the eventual re-entry point) was measured. Results: Outback success was 93% (93/100); only 7 cases failed owing to heavy calcification (5/52 aortoiliac vs 2/48 infrainguinal, p=0.44). Re-entry was highly accurate, with a re-entry distance of ~1 cm in both subgroups (1.2±0.1 cm in aortoiliac vs 1.3±0.1 cm in infrainguinal, p=0.40). There were no major and 17 minor complications (9/52 aortoiliac vs 8/48 infrainguinal, p=0.93). Results are in line with the systematic review that identified 11 studies (only 1 randomized trial) involving mostly the femoropopliteal segment (119 aortoiliac and 464 infrainguinal segments). The pooled Outback success rate was 90% (95% confidence interval 85% to 94%) and the pooled complication rate was 4.3% (95% confidence interval 1.6% to 8.3%). Conclusion: The Outback device is safe and has a very high rate of achieving targeted true lumen re-entry, which minimizes the sacrifice of healthy vessel in the aortoiliac and infrainguinal arteries.

Percutaneous versus surgical management of lower extremity peripheral artery disease

Lower extremity peripheral artery disease (PAD) is highly prevalent and can manifest as intermittent claudication or, in the most advanced form, critical limb ischemia. Revascularization, which can be accomplished by an endovascular or surgical approach, is performed to improve quality of life or, in severe cases, for limb salvage. Over the past decade, percutaneous catheter-based techniques have improved such that acute procedural success is high even in complex anatomy. Patency rates have also increased with the use of atherectomy devices and drug-eluting stents. Often, patients with PAD have comorbidities that increase the risk of cardiovascular complications with surgical procedures. These factors have led to the adoption of an endovascular first strategy with surgical management reserved for selected patients. This review focuses on the most current clinical trials of endovascular therapy for PAD. In addition, older but relevant studies comparing endovascular and surgical approaches and contemporary surgical trials are presented for reference.

Rendezvous technique for recanalization of long-segmental chronic total occlusion above the knee following unsuccessful standard angioplasty

Purpose

To assess the technical feasibility and efficacy of the rendezvous technique, a type of subintimal retrograde wiring, for the treatment of long-segmental chronic total occlusions above the knee following unsuccessful standard angioplasty.

Methods

The rendezvous technique was attempted in eight limbs of eight patients with chronic total occlusions above the knee after standard angioplasty failed. The clinical symptoms and ankle-brachial index were compared before and after the procedure. At follow-up, pain relief, wound healing, limb salvage, and the presence of restenosis of the target vessels were evaluated.

Results

The rendezvous technique was performed successfully in seven patients (87.5%) and failed in one patient (12.5%). Foot pain improved in all seven patients who underwent successful treatment, with ankle-brachial indexes improving from 0.23 ± 0.13 before to 0.71 ± 0.09 after the procedure ( P < 0.001). At the end of the follow-up period, the visual analogue scale improved from 6.86 ± 1.57 to 1.57 ± 1.27 ( P < 0.001). Non-healing ulcers in three patients either healed (n = 2) or improved (n = 1). No major amputation was necessary. Kaplan–Meier analyses revealed that stenosis-free rate was 83.3% at six months and 41.7% at 12 months.

Conclusion

The rendezvous technique is a feasible and effective treatment for chronic total occlusions above the knee when standard angioplasty fails.

Treatment of complex atherosclerotic femoropopliteal artery disease with a self-expanding interwoven nitinol stent: Midterm results

OBJECTIVE

To examine the efficacy and durability of an interwoven self-expanding nitinol stent for the treatment of superficial femoral and popliteal arteries.

METHOD

Consecutive patients with severely diseased superficial femoral and popliteal arteries who received SUPERA® stents were retrospectively identified. The patients were followed for 12 months by Doppler ultrasound examinations, stent roentgenograms, and estimation of Rutherford-Becker class and ankle-brachial index.

RESULTS

From July 2012 to May 2014, 42 limbs in 36 patients (mean age, 61.5 ± 7.5 years; 75% male) were treated with angioplasty and primary stenting. Total occlusions were present in 14 limbs, and 63.8% had either moderate or severe calcification. The mean (±SD) lesion length was 105 mm (±28). Primary patency was 91.4% at 6 months and 85.7% at 12 months. The ankle brachial index increased from 0.57 ± 0.19 preoperative to 0.91 ± 0.12 postoperative. There was no procedural or device-related morbidity or mortality after revascularization and only one major amputation was observed on follow-up.

CONCLUSIONS

Our experience shows that, Supera stents are safe and effective in our cohort of patients, with acceptable patency rates. There were no stent fractures so far even with stenting of the femoropopliteal segments. Stent design provides a viable option for high-grade obstructive disease in the femoropopliteal artery.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Vibrational angioplasty in recanalization of chronic femoropopliteal arterial occlusions: single center experience

PURPOSE

This prospective study aims to present the overall success rate, safety and long-term outcome of vibrational angioplasty technique, in the treatment of chronic total femoropopliteal occlusions in our institute.

METHODS

Between October 2000 and December 2008, patients with chronic total femoropoliteal arterial occlusions, treated with vibrational angioplasty during the same session after a failed attempt with conventional recanalization technique, were included. Patient's follow up included serial ankle-brachial index measurements and arterial duplex ultrasound examinations at 1, 3, 6, 12, 24, 36 and 48 months.

RESULTS

Twenty-seven patients (16 males and 11 females) and twenty-eight lesions were included in our study. Twenty-five lesions (89.3%) were successfully recanalized. Pain relief was noticed in twenty-one cases. From ten lesions with tissue loss (ulcer or gangrene) in successfully recanalized occlusions, six healed without major, or minor amputation. One non-healing amputation stump was healed after recanalization, without further complications. Four limbs underwent amputation (one minor and three major) despite successful recanalization, however all had an excellent healing of the amputation stump without further complications. The Kaplan-Meier test demonstrated 90%, 85% and 70% amputation-free survival rate at 12, 24 and 36 months, respectively. No major or minor complications were encountered.

CONCLUSIONS

Vibrational angioplasty is a safe, effective and durable endovascular technique for the treatment of chronic total occlusions in patients with limb ischemia that would be difficult to recanalize using conventional intraluminal techniques.

Peripheral arterial calcification: prevalence, mechanism, detection, and clinical implications

Vascular calcification (VC), particularly medial (Mönckeberg's medial sclerosis) arterial calcification, is common in patients with diabetes mellitus and chronic kidney disease and is associated with increased cardiovascular morbidity and mortality. Although, the underlying pathophysiological mechanisms and genetic pathways of VC are not fully known, hypocalcemia, hyperphosphatemia, and the suppression of parathyroid hormone activity are central to the development of vessel mineralization and, consequently, bone demineralization. In addition to preventive measures, such as the modification of atherosclerotic cardiovascular risk factors, current treatment strategies include the use of calcium-free phosphate binders, vitamin D analogs, and calcium mimetics that have shown promising results, albeit in small patient cohorts. The impact of intimal and medial VC on the safety and effectiveness of endovascular devices to treat symptomatic peripheral arterial disease (PAD) remains poorly defined. The absence of a generally accepted, validated vascular calcium grading scale hampers clinical progress in assessing the safety and utility of various endovascular devices (e.g., atherectomy) in treating calcified vessels. Accordingly, we propose the peripheral arterial calcium scoring system (PACSS) and a method for its clinical validation. A better understanding of the pathogenesis of vascular calcification and the development of optimal medical and endovascular treatment strategies are crucial as the population ages and presents with more chronic comorbidities.

Successful outside-the-stent stenting for an occluded primary stented superficial femoral artery

A 61-year-old man with in-stent occlusion of the superficial femoral artery (SFA) underwent the endovascular therapy using a subintimal technique. The wire was intentionally advanced into the subintimal space next to the occluded stent in the SFA, and a stent was implanted in a double barrel fashion outside of the in-stent occlusion site. The procedure was performed without any complications and with the successful angiographic and intravascular ultrasound imaging results. At 1-year follow-up, the patient still had no leg complaints and the stent was still shown as patent. The procedure might be a useful technique when the recanalization was proved impossible after several attempts to recanalize the primary occluded stent in the SFA.

Retroperitoneal hematoma: an unexpected complication during intervention on an occluded superficial femoral artery via a retrograde popliteal artery approach

Peripheral arterial disease involvement of the superficial femoral artery (SFA) is common. Different endovascular techniques are used successfully for revascularization of this artery. A retrograde approach to chronic total occlusion (CTO) of the SFA through the ipsilateral popliteal artery has been used occasionally if an antegrade approach is not feasible or has failed. Some of the known complications encountered during this approach are arteriovenous fistula formation at the access site, occlusion of the popliteal artery if closure devices are used, and bleeding. There are no reports of perforation or bleeding of the SFA or the external iliac artery (EIA) during a popliteal approach, probably due to lack of flow in the occluded segment of the SFA. We report a case in which a retroperitoneal hematoma occurred due to retrograde blood flow through the established true channel in the proximal SFA and subsequently to the dissection plane with a wire tip perforation in the EIA, which was treated by stopping retrograde filling with prolonged balloon inflation in the distal SFA before the CTO.