Cephalic arch restenosis rates in hemodialysis patients with brachiocephalic fistulae: a retrospective multicenter analysis of 3301 patients

Six-month safety and efficacy outcomes from the randomized-controlled arm of the WRAPSODY Arteriovenous Access Efficacy (WAVE) trial

Stenosis within the arteriovenous fistula (AVF) of hemodialysis patients leads to vascular access dysfunction and inadequate hemodialysis. Percutaneous transluminal angioplasty (PTA) is the standard therapy for stenosis. However, rates of restenosis and loss of access patency remain high. Outcomes of a novel cell-impermeable endoprosthesis (CIE) have not been investigated in this setting. Therefore, our study was designed to address this as a prospective, international, multicenter pivotal trial (NCT04540302) with 245 patients with stenosis in their venous outflow circuit randomized to treatment: 122 receiving CIE and 123 receiving PTA across 43 international centers. Primary endpoints included target lesion primary patency (TLPP) at six months (freedom from clinically driven target lesion revascularization or target lesion thrombosis) and freedom from safety events through 30 days post-index procedure that affected the access circuit and resulted in reintervention, hospitalization, or death. Access circuit primary patency (ACPP) was evaluated as a secondary efficacy endpoint. Six-month TLPP and ACPP were significantly higher for the CIE cohort versus PTA (TLPP: 89.6% vs. 62.3%; ACPP: 72.2% vs. 57.0%). Thirty days post-index procedure, there was no statistically significant difference in the freedom from safety events for the CIE versus PTA (96.6 vs. 95.0%). No differences were observed in adverse events between either cohort. Our study shows that among patients with stenosis in their AVF, the CIE was superior to PTA with respect to six-month TLPP and ACPP with no observed difference in 30-day primary safety events.

Clinical outcome of percutaneous angioplasty and covered stent placement for treatment of left brachiocephalic vein obstruction in hemodialysis patients

BACKGROUND

Left brachiocephalic vein (LBV) obstruction is a common complication in patients undergoing hemodialysis. This study aimed to compare the clinical characteristics and outcomes of patients with LBV obstruction who underwent percutaneous angioplasty or stenting.

METHODS

We performed a retrospective study of 67 hemodialysis patients with LBV stenosis or occlusion who underwent percutaneous transluminal angioplasty (PTA; n = 25) or percutaneous transluminal stenting (PTS; n = 42). We compared the clinical characteristics, lesion features, and patency between the two groups of patients.

RESULTS

The average age, sex, smoking history, body mass index, obstruction period, comorbidities, and clinical manifestations were comparable between the PTA and PTS groups. Prior ipsilateral catheterization was less common in the PTS group than in the PTA group (14.3% vs 36.0%, p < 0.05). Smaller sized balloons were used in the PTS group than in the PTA group (p < 0.05). The overall primary patency rates were similar between the two groups, whereas the secondary patency rate in the PTS group was higher than that in the PTA group (p < 0.05). The average age, sex, smoking history, body mass index, obstruction period, prior ipsilateral catheterization, comorbidities, and types of lesions were comparable between patients with or without restenosis, while patients with restenosis had a higher percentage of high venous pressure than those without restenosis (87.5% vs 60.5%, p < 0.05).

CONCLUSION

The primary patency rates were similar in the angioplasty and the stenting groups. Stenting has a significantly higher secondary patency rate than angioplasty alone for treating LBV obstruction and is required more commonly in patients without prior ipsilateral catheterization.

Management of cephalic arch stenosis in hemodialysis access: Updated systematic review and meta-analysis

INTRODUCTION

Cephalic arch stenosis (CAS) is often recurrent, resistant to treatment and the intervention outcome is not well validated so far. We purposed to assess the clinical outcomes of CAS treatment in patients with hemodialysis access.

METHODS

Electronic bibliographic sources were searched up to December 4 2023 to identify studies reported outcome after treating CAS. Direct and indirect evidence was combined to compare odds ratios (OR) and surfaces under the cumulative ranking curves across the different treatment modalities through meta-analysis and network meta-analyses (NMA). This systematic review was conducted in accordance with the PRISMA-P. The review is registered in PROSPERO (CRD42022296513).

RESULTS

Four randomized controlled trials (RCTs) and 15 non-RCTs were included in the analysis. The study population differed in fistula type, restenosis or thrombosis, and significant heterogeneity was observed among the publications. The risk of bias was low to serious. Meta-analysis found no significant difference between DCB and PTA in primary patency at 6 and 12 months (OR 1.16 and 0.60, respectively; low certainty of evidence). Favorable result with STG compared to stent or PTA at 3, 6, and 12 month was observed (OR 4.28, 5.13, and 13.12, and 4.28, 5.13, 13.12, respectively; low certainty of evidence). Regarding primary patency, the treatment rankings, from highest to lowest, were STG (92.7%), transposition (76.0%), stent (67.5%), DCB (46.3%), and PTA (64.5%) at 12 months.

CONCLUSION

Despite data limitations, the low-quality evidence suggests that STG may merit consideration as a primary treatment option when all alternatives are applicable, given their potential for better primary patency and higher treatment ranking.

Outcomes of Surgical and Endovascular Treatment for Cephalic Arch Stenosis in Proximal Arteriovenous Fistula

Purpose

The cephalic arch is a significant site of stenosis in proximal arteriovenous fistulas (AVFs) that contributes to access dysfunction and thrombosis. This study aimed to evaluate the outcomes of surgical treatment (ST) and endovascular treatment (ET) for cephalic arch stenosis (CAS).

Materials and Methods

A total of 62 patients with proximal AVF who underwent CAS revision using either ST or ET were enrolled between January 2018 and March 2023. In the ET group, only the initial ET following AVF formation was considered, to mitigate bias. In the ST group, central transposition of the native AVF (transposition group) or interposition of the prosthetic graft into the proximal basilic or axillary vein (interposition group) was performed. We evaluated primary and functional patency based on these groups and calculated the number of patency loss events after CAS treatment.

Results

Of the 62 patients, 38 (61%) were male, with a mean age of 66.4 years. ST was performed in 26 (42%) patients, including transposition in 16 and interposition in 10, whereas ET was administered to 36 patients during the study period. Among the ST recipients, 42% had a history of ET for CAS. The incidence of AVF thrombosis was marginally higher in the ST group than in the ET group (39% vs. 19%, P=0.098). The primary patency rates at 6 months, 1 year, and 3 years were 87%, 87%, and 66% in the transposition group; 45%, 23%, and 11% in the interposition group; and 66%, 49%, and 17% in the ET group, respectively. Notably, the primary patency of the transposition group was significantly higher than that of the interposition (P=0.001) and ET groups (P=0.016). The frequency of patency loss events per person-year after the initial revision was 0.40, 0.52, and 1.42 in the transposition, interposition, and ET groups, respectively.

Conclusion

Transposition exhibited the most favorable primary patency rate and the lowest number of subsequent patency loss events during follow-up despite the higher rates of AVF thrombosis and previous ET at presentation. Consequently, transposition should be actively considered in eligible patients with CAS.

Characterization of hemodialysis fistulas experienced abrupt thrombosis and determination of a proper follow-up protocol: A retrospective cohort study and an interventionist's perspective

Abrupt thrombosis is a form of thrombosis that occurs unexpectedly and without being preceded by hemodialysis fistula (AVF) dysfunction during dialysis. We found that AVFs with a history of abrupt thrombosis (abtAVF) appeared to have more episodes of thrombosis and required more frequent interventions than those without such history. Therefore, we sought to characterize the abtAVFs and examined our follow-up protocols to determine which one is optimal. We performed a retrospective cohort study using routinely collected data. The thrombosis rate, AVF loss rate, thrombosis-free primary patency, and secondary patency were calculated. Additionally, the restenosis rates of the AVFs under the follow-up protocol/sub-protocols and the abtAVFs were determined. The thrombosis rate, procedure rate, AVF loss rate, thrombosis-free primary patency, and secondary patency of the abtAVFs were 0.237/pt-yr, 2.702/pt-yr, 0.027/pt-yr, 78.3%, and 96.0%, respectively. The restenosis rate for AVFs in the abtAVF group and the angiographic follow-up sub-protocol were similar. However, the abtAVF group had a significantly higher thrombosis rate and AVF loss rate than AVFs without a history of abrupt thrombosis (n-abtAVF). The lowest thrombosis rate was observed for n-abtAVFs, followed up periodically under the outpatient or angiographic sub-protocols. AVFs with a history of abrupt thrombosis had a high restenosis rate, and periodic angiographic follow-up with a mean interval of 3 months was presumed appropriate. For selected populations, such as salvage-challenging AVFs, periodic outpatient or angiographic follow-up was mandatory to extend their usable lives for hemodialysis.