Twelve-Month Outcomes From the Japanese Post-Market Surveillance Study of the Viabahn Endoprosthesis as Treatment for Symptomatic Peripheral Arterial Disease in the Superficial Femoral Arteries

Purpose: To assess the midterm safety and effectiveness of the Gore® Viabahn® Endoprosthesis as treatment for symptomatic peripheral arterial disease (PAD) in the superficial femoral arteries (SFA). Materials and Methods: A prospective, multicenter, post-market surveillance study was conducted in Japan. Patients with symptomatic SFA lesions ≥ 10 cm and reference vessel diameters ranging from 4.0 to 7.5 mm were eligible for enrollment; patients with traumatic or iatrogenic vessel injury in the thoracic, abdominal, or pelvic arteries were excluded. Outcomes evaluated at 12 months were primary patency (PP), primary-assisted patency (PAP), secondary patency (SP), freedom from target lesion revascularization (fTLR), occurrence of device- or procedure-related serious adverse events (SAEs), and stent fractures. Results: From August 2016 to May 2017, 321 patients were enrolled at 64 Japanese sites (mean age, 73.9±8.7 years; 77.3% male). Hypertension, diabetes, and end stage renal disease were present in 84.4%, 54.8%, and 23.1% of patients, respectively. Mean lesion length was 23.6 cm±6.6 cm, with lesions ≥ 15 cm in 271 patients (84.4%). TASC C/D lesions accounted for 86.6% (39.1% TASC C, 47.5% TASC D); 26.5% had critical limb ischemia. Baseline ABI was 0.60±0.16. A total of 562 devices were implanted in 324 limbs, with a majority of patients (68.8%) receiving 2 stents. Through 12 months, 92.1% of patients were evaluable. Kaplan-Meier-estimated PP, PAP, and SP at 12 months was 85.6%, 91.7%, and 94.8%, respectively. Twelve-month fTLR was 92.3%. Mean change in ABI at 12 months was 0.343±0.21; mean improvement in Rutherford class was 2.5. Device- or procedure-related SAEs occurred in 3.1% through 30 days, with a majority of early SAEs consisting of access complications. Through 12 months, a cumulative 10.6% had device- or procedure-related SAEs, with the most common being device occlusions in 4.0%. Lower limb amputation occurred in 0.9% and was related to pre-existing ulceration or gangrene in all 3 cases. No stent fractures were observed at 12-month x-ray evaluation. Conclusion: In a real-world Japanese patient population characterized by long SFA lesions and complex PAD, the Viabahn endoprosthesis was associated with excellent patency rates through 12 months and an acceptable safety profile.

SIroliMus coated angioPlasty versus plain balloon angioplasty in the tREatment of dialySis acceSs dysfunctION (IMPRESSION): study protocol for a randomized controlled trial

Background Percutaneous transluminal angioplasty is the current standard treatment for arteriovenous fistula (AVF) stenosis. The mid- and long-term patency with plain balloon angioplasty (PBA) is however far from satisfactory. While paclitaxel-coated balloon angioplasty has been shown to be superior to PBA, concern over its safety profile has recently arisen after a reported possible increased mortality risk with a meta-analysis of large lower limb studies. An angioplasty balloon with a new type of drug coating, the sirolimus-coated balloon (SCB), has been proven to improve patency in the coronary arteries. However, its effect on AV access has yet to be studied. Methods/design This is an investigator-initiated, prospective, multicenter, double-blinded, randomized controlled clinical trial to assess the effectiveness of SCB compared to PBA in improving the patency of AVF after angioplasty. A total of 170 patients with mature AVF that requires PTA due to AVF dysfunction will be randomly assigned to treatment with a SCB or PBA at a 1:1 ratio, stratified by location of AVF and followed up for up to 1 year. The inclusion criteria include [1] adult patient aged 21 to 85 years who requires balloon angioplasty for dysfunctional arteriovenous fistula [2]; matured AVF, defined as being in use for at least 1 month prior to the angioplasty; and [3] successful angioplasty of the underlying stenosis with PBA, defined as less than 30% residual stenosis on digital subtraction angiography (DSA) and restoration of thrill in the AVF on clinical examination. The exclusion criteria include thrombosed or partially thrombosed access circuit at the time of treatment, presence of symptomatic or angiographically significant central vein stenosis that requires treatment with more than 30% residual stenosis post angioplasty, and existing stent placement within the AVF circuit. The primary endpoint of the study is access circuit primary patency at 6 months. The secondary endpoints are target lesion primary patency; access circuit-assisted primary patency; access circuit secondary patency at 3, 6, and 12 months; target lesion restenosis rate at 6 months; total number of interventions; complication rate; and cost-effectiveness. The trial is supported by Concept Medical. Discussion This study will evaluate the clinical efficacy and safety of SCB compared to PBA in the treatment of AVF stenosis in hemodialysis patients. Trial registration ClinicalTrials.govNCT04409912. Registered on 1 June 2020

Endovascular Reconstruction for Total Aorto–Iliac Occlusion

Objectives: To analyze outcomes following endovascular treatment of total occlusion of the infrarenal aorta and aorto–iliac bifurcation in a multicenter Italian registry. Methods: It is a multicenter, retrospective, observational cohort study. From January 2015 to December 2018, 1306 endovascular interventions for aorto–iliac occlusive disease were recorded in the vascular registry. For this analysis, only patients treated for total occlusion of the infrarenal aorta and aorto–iliac bifurcation were included. Early (<30 days) primary outcomes of interest were technical success and mortality. Late major outcomes were primary and secondary patency and freedom from conversion to open aortic surgery. Results: A total of 54 (4.1%) patients met the inclusion criteria. Total percutaneous revascularization was possible in 41 (75.9%) patients and hybrid (endo plus open) intervention in 13 (24.1%) patients. The kissing-stent-graft technique was used in 45 (83.3%) cases, covered endovascular reconstruction of the aortic bifurcation (CERAB) in 5 (9.2%), and a unibody endograft deployed in 4 (7.4%). Technical success was 98.1% (n = 53). There were no episodes of intraoperative or perioperative vessel rupture. Conversion to open surgery was not necessary, and there were no in-hospital deaths. The median patient follow-up time was 16 months (interquartrile range [IQR], 6-27). The estimated primary patency rate was 95.8% ± 0.03 (95% confidence interval [CI]: 85.5-98.9) at 1 year, 91.4% ± 0.05 (95% CI: 76.2-97.2) at 2 years, and 85 ± 0.08 (95% CI: 64.5-94.6) at 3 years. Cox regression analysis demonstrated that sex (hazard ratio [HR]: 0.96; 95% CI: 0.15-6.23, p = 0.963), extent of the occlusion (HR: 0.28; 95% CI: 0.05-1.46, p = 0.130), calcium score (HR: 1.88; 95% CI: 0.31-11.27, p = 0.490), or type of endovascular reconstruction (HR: 0.80; 95% CI: 0.13-5.15, p = 0.804) did not affect primary patency. Secondary patency was 95.5% ± 0.04 (95% CI: 78.4-99.2) at 3 years. No patients required late conversion to open surgical bypass. Conclusions: Endovascular reconstruction for total occlusion of the infrarenal aorta and aorto–iliac bifurcation was successful using a combination of percutaneous and hybrid revascularization techniques. Estimated patency rates at 3 years of follow-up are promising and are unaffected by the extent of occlusion or type of revascularization.

Long-term patency rate of the translocated autologous saphenous vein versus prosthetic material in vascular access surgery for haemodialysis and parenteral nutrition

Objective: To evaluate the long-term patency rate of the arteriovenous angioaccess (AVA) with interposition of either autologous or prosthetic material as a last option for vascular access in the upper extremity. Methods: This is a retrospective chart review study of all patients who received an AVA with autologous saphenous vein (SV Group, n = 38) or prosthetic material (PTFE Group, n = 25) as a conduit from the year 1996 to 2020 in the Radboud University Medical Center (Radboudumc). Data were retrospectively extracted from two prospectively updated local databases for vascular access, one for haemodialysis (HD) and one for parenteral nutrition (PN). When required, the medical records of each patient were used. Data were eventually collected anonymously and analysed in SPSS 25. Kaplan-Meier life-tables were used for the statistical analysis. Results: Primary patency at 12 and 48 months was 30% and 20% in the SV group and 45% and 14% in the PTFE group. No significant difference was shown in the median primary patency rate ( p = 0.715). Secondary patency at 12 and 48 months was 63% and 39% in the SV group and 55% and 19% in the PTFE group. This was considered a significant difference in median secondary patency in favour of the SV with 41.16 ± 17.67 months against 13.77 ± 10.22 months for PTFE ( p = 0.032). The incidence of infection was significantly lower in the SV group ( p = 0.0002). A Kaplan-Meier curve could not detect a significant difference in secondary patency between the access for haemodialysis and the access for parenteral nutrition. The secondary patency of the SV in parenteral nutrition access, was significantly higher when compared with PTFE ( p = 0.004). Conclusion: The SV can be preferred over PTFE when conduit material is needed for long-term vascular access for HD or PN treatment due to its higher secondary patency and lower infection risk.

Single-centre experience with endovascular rotational thrombectomy for single session salvage of thrombosed arteriovenous fistulas and grafts

Objectives: This paper documents our experience and outcomes of using a relatively new endovascular rotational thrombectomy device for salvage of thrombosed vascular access. Methodology: A retrospective study reviewing patients with thrombosed native AVF or AVG who underwent endovascular declotting using a rotational thrombectomy device between November 2018 and May 2020 at a tertiary university hospital in Southeast Asia. We evaluated demographics, procedural data, technical and procedural success, patency rates and complications. Results: A total of 40 patients underwent single session endovascular declotting of thrombosed vascular access. The mean follow-up period was 21.6 months (range 13.4–31 months). The technical success was 92.5% and clinical success was 80%. About 50% of patients had concomitant thrombolysis for pharmacomechanical thrombectomy. One patient had a myocardial infarction during the post-operative period. There were no other major complications within 30 days. The primary patency was 45.5% at 6 months and 22.7% at 12 months. Assisted primary patency was 68.1% at 6 months and 61.6% at 12 months, which was maintained up to 2 years. The secondary patency was 84.1% at 6 and 12 months. Conclusion: Our study shows that rotational thrombectomy device for single session thrombectomy of thrombosed arteriovenous fistulas and grafts is safe and effective. A high technical and clinical success rate was achieved, with low complication rates and specific advantages compared to other techniques, including reduced length of hospital stay. Our reported mid-term outcomes are reasonable with an assisted primary patency of 62% at 12 and 24 months. The use of newer techniques and novel dedicated thrombectomy devices show promise.

Trans-radial percutaneous intervention for thrombosed hemodialysis access: A single-center experience

Background: Traditionally, percutaneous transluminal angioplasty (PTA) is a first-line approach for stenosed dialysis accesses and has been performed through the non-thrombosed vein segment. For thrombosed accesses, thrombectomy (whether open or percutaneous) is a standard approach. The primary objective of our study is to determine the clinical and technical outcomes of the trans-radial approach of PTA among thrombosed dialysis accesses, in terms of safety and feasibility, technical and clinical aspects and factors influencing them, as well as assisted primary patency, secondary patency at 6 and 12 months. Methods: This is a single-center retrospective study that included 150 patients over 3 years. About 123 patients underwent successful percutaneous balloon angioplasty through the radial access. Results: We report an overall technical and clinical success rate of 82%, assisted primary patency rate of about 90.25% at 3 months, 82.93% at 6 months, 73.18% at 1 year, and secondary patency rate of 94% at 1 year. Twenty-seven patients were referred for surgical revisions/creation of a new fistula for reasons like inability to pass wire (6 patients), unfavorable anatomical variations like aneurysms at the proximal segments (5 patients), inability to cross the fistula (5 patients), and persistent fistula dysfunction with no flow after initial balloon dilatation (11 patients). Three patients had hematoma at the radial access site (2.5%) while two patients had the AV fistula segment rupture and were successfully treated conservatively. Conclusion: We conclude that PTA through the trans-radial approach to completely thrombosed hemodialysis accesses is a good alternative to transvenous access and has a very good assisted primary patency and secondary patency at 1 year without major complications.

MILLER Banding Procedure for Treatment of Dialysis Access–Related Steal Syndrome, Pulmonary Hypertension, and Heart Failure

A Minimally Invasive Limited Ligation Endoluminal-assisted Revision (MILLER) banding procedure has been used for treating patients with dialysis access–related steal syndrome (DASS) and high-flow vascular access–related pulmonary hypertension (PHT) and heart failure (HF). We performed a retrospective analysis of patients undergoing the MILLER procedure performed for DASS, HF, and PHT from our Vascular Access Database from September 2017 to October 2019. Outcomes included primary patency of banding, primary assisted patency, and secondary patency, using time-to-event analyses with Kaplan-Meier curves and life tables to estimate 6- and 12-month rates. A total of 13 patients (6 men and 7 women, mean age 60 ± 14 years) underwent the MILLER procedure, 6 patients for DASS and 7 patients for pulmonary hypertension and heart failure (PHT/HF). Technical success was achieved in all patients. The longest duration of follow-up was 28 months (median 12 months [IQR 7, 19]). One patient died at 1 month after the intervention due to stroke. One patient developed access thrombosis of the graft 3 days after the procedure. Repeat banding was required in 1 patient 8 months after the first procedure. The 6-month primary patency rate of banding following this procedure was 83% while the 12-month rate was 66%. The 6- and 12-month secondary patency rates were 87% and 75%, respectively. The MILLER procedure can be performed for DASS and PHT/HF with improvement of symptoms and good long-term patency rates. Additional interventions to maintain patency and efficacy are required on long-term follow-up.

Vessel diameter and close surveillance helps predict early patency in native arteriovenous fistulas

Introduction: Arteriovenous fistulas are the preferred method of vascular access for haemodialysis. Data suggests patency rates can be low and may be related to vessel diameters prior to creation. We use specific size criteria for fistula selection. We aimed to establish patency rates in relation to vessel size and whether other factors affect fistula patency. Methods: Consecutive patients undergoing radiocephalic (RCF) or brachiocephalic (BCF) creation between 2016 and 2018 were analysed. Preoperative arterial and venous diameters were collected. Six-week and six-month primary and secondary patency rates were analysed to establish any impact of vessel size on patency and re-intervention rates between groups. A univariate analysis was performed. Results: Ninety four RCFs and 101 BCFs were created. Median artery and vein size for RCF were 2.7 and 3.0 mm respectively. For BCF, they were 4.6 and 4.3 mm respectively. At 6-weeks, overall satisfactory patency for RCF and BCF combined was 91.8%. 89.7% demonstrated primary patency; 2.1% secondary patency. At 6-months, overall patency was 78.7%; 58.5% demonstrated primary patency, 20.2% secondary patency. A univariate analysis, for both groups, revealed vein size was a significant predictor of overall satisfactory patency at 6-weeks, with larger veins more likely to remain patent ( p = 0.025 RCF, p = 0.007 BCF). However, artery size was not predictive ( p = 0.1 RCF, p = 0.5 BCF). At 6-months, neither artery nor vein diameter were predictive in either group. When comparing size of vessel based on fistula type, vessels used to create RCFs were smaller than those for BCFs ( p < 0.001). RCFs were more likely to receive endovascular intervention or occlude when compared to BCFs ( p = 0.014). Discussion: Excellent patency and maturation rates can be achieved using fairly strict vessel size criteria. Vein size might be the more important predictor of early success. RCFs can be challenging due to smaller vessels, but maturation rates can be optimised by close surveillance and aggressive re-intervention.

Upper thigh loop prosthetic arterio-venous grafts (AVG) for dialysis access: An Indian perspective

Introduction: Hemodialysis forms the most common replacement therapy for majority of Indians suffering from chronic kidney disease (CKD). Multiple access failure and central vein stenosis has become commonplace in Indian dialysis access patients and there is a burgeoning need for more advanced hemodialysis (HD) access options. Upper thigh arterio-venous grafts (AVG) are seldom inserted due to fear of infection and limb ischemia. Materials and methods: This is a single institutional, retrospective, descriptive case study of consecutive patients who underwent upper thigh prosthetic AVG over a period of 7 years. All these patients had exhausted options of upper limb access and or had central vein stenosis. AVG from the proximal superficial femoral artery (SFA) to the proximal great saphenous vein (GSV) in a loop configuration using polytetrafluoroethylene (PTFE) was carried out in the upper thigh. Results: A total of 24 patients had undergone upper thigh loop AVG. Their age varied from 24 to 77 years. The median follow-up period was 3 years. Five of these grafts developed infection (21%) which led to primary failure. A primary patency of 71% (17/24 patients) was achieved at 1 year. Thrombosis developed at a mean of 16.7 months after the primary procedure. Adjunctive procedures such as thrombectomy, segmental replacement of graft, patch angioplasty, balloon angioplasty, and stenting were required in 75% of patients to achieve a secondary patency of 86% at 1 year. Three grafts were explanted without limb loss. Conclusion: Upper thigh loop AVG forms a reliable alternate dialysis access option for patients with failed upper limb access sites or central vein occlusion. Adjunctive procedures are key to maintaining patency in these grafts. Good secondary patency is achievable, and the infection rates are similar to arm AVG. Close follow-up and timely intervention are key to long term dialysis through these grafts.

Primary Catheter-Directed Thrombolysis For Porto-Mesenteric Venous Thrombosis (PMVT) In Non-Cirrhotic Patients.

Purpose: To report our technique, treatment strategy and clinical outcomes for porto-mesenteric venous thrombosis (PMVT) in non-cirrhotic patients.Methods: 16 non-cirrhotic PMVT patients (mean age: 48.6 years) with imminent intestinal ischemia were enrolled from 2004-2020. 8 patients presented thrombus extension into the peripheral mesenteric vein, close to the venous arcade. Transhepatic catheter-directed thrombolysis (CDT) was performed by urokinase infusion (60,000-30,000 IU/hour concomitant with heparin 300-400 IU/hour), catheter aspiration and/or balloon dilation/stent placement. Additional intra-arterial mesenteric infusion of urokinase (30,000 IU/hour) was given in patients with the peripheral mesenteric venules involved. Transjugular intrahepatic porto-systemic shunt (TIPS) was created in patients with poor recanalization of the intrahepatic portal flow (PV). Results: The transhepatic route was adopted in all patients, with adjunct indirect mesenteric arterial thrombolytic infusion in 8 patients. A total of up to 20.4 million IU urokinase was infused for 1-30 days’ treatment duration. TIPS was created in 3 patients with recanalization failure of the intrahepatic PV. Technical success was achieved in 100% of patients with complete recanalization of 80% and partial recanalization of 20%. No major procedure-related complications were encountered. The 30-day mortality rate was 6.7%. The overall 1- and 2-year primary and secondary patency were both 74.0% and 84.6% respectively. Conclusions: CDT can be performed as a primary salvage treatment once the diagnosis is made. CDT via the transhepatic route with tailored thrombolytic regimen is safe and effective for both acute and chronic PMVT . TIPS creation can be preserved in non-cirrhotic PMVT patients if intrahepatic PV recanalization fails.