Hemodialysis Arteriovenous Fistula Research Articles

Assessment of volume flow rate in arteriovenous fistulas with a novel ultrasound Doppler device (earlybird): Trend analysis, comparison of methods, and inter- and intra-rater reliability.

An accessible tool is required to analyze volume flow trends in arteriovenous fistulas for hemodialysis. Earlybird, an easy-to-place ultrasound Doppler device, has shown comparable accuracy to duplex ultrasound. In this study, we compared volume flow measurements obtained with duplex ultrasound and the dilution technique to an enhanced earlybird device, featuring a dual Doppler probe system, eliminating the requirement for a known insonation angle. Nine patients with a distal radiocephalic arteriovenous fistula were monitored for 12 months with regular volume flow measurements. Correlation and inter- and intra-class reliability analyses were conducted. An overall moderate correlation was observed between earlybird and duplex ultrasound or dilution technique (intraclass correlation coefficient = 0.606 (95% confidence interval 0.064, 0.721) and 0.581 (0.039, 0.739), respectively). Duplex ultrasound compared to dilution measurements, demonstrated an overall moderate correlation (0.725 (0.219, 0.843)). Correlation between earlybird and duplex ultrasound was stronger for the arteriovenous fistula (0.778 (0.016, 0.901)) than the brachial artery (0.381 (-0.062, 0.461)). For earlybird, inter-rater reliability was excellent for the arteriovenous fistula (0.907 (0.423, 0.930)) and poor for the brachial artery (0.430 (0.241, 0.716)). Duplex ultrasound showed a good inter-rater reliability (arteriovenous fistula: 0.843 (0.610, 0.871), brachial artery: 0.819 (0.477, 0.864)). The overall intra-rater reliability was good for duplex ultrasound (rater A: 0.893 (0.727, 0.911); rater B: 0.853 (0.710, 0.891)), while excellent for earlybird (rater A: 0.905 (0.819, 0.928); rater B: 0.921 (0.632, 0.969)). We observed a weaker correlation in the measurements of volume flow rates in arteriovenous fistulas when obtained using earlybird compared to dilution technique, unlike the comparison between duplex ultrasound and the dilution technique. However, inter-rater reliability for the arteriovenous fistula was excellent with earlybird and good with duplex ultrasound, indicating the potential of earlybird as a tool for frequent measurements, enabling trend surveillance and predicting adverse outcomes.

Doppler ultrasound surveillance of recently formed haemodialysis arteriovenous fistula: the SONAR observational cohort study.

Arteriovenous fistulas are considered the best option for haemodialysis provision, but as many as 30% fail to mature or suffer early failure. To assess the feasibility of performing a randomised controlled trial that examines whether, by informing early and effective salvage intervention of fistulas that would otherwise fail, Doppler ultrasound surveillance of developing arteriovenous fistulas improves longer-term arteriovenous fistula patency. A prospective multicentre observational cohort study (the 'SONAR' study). Seventeen haemodialysis centres in the UK. Consenting adults with end-stage renal disease who were scheduled to have an arteriovenous fistula created. Participants underwent Doppler ultrasound surveillance of their arteriovenous fistulas at 2, 4, 6 and 10 weeks after creation, with clinical teams blinded to the ultrasound surveillance findings. Fistula maturation at week 10 defined according to ultrasound surveillance parameters of representative venous diameter and blood flow (wrist arteriovenous fistulas: ≥ 4 mm and > 400 ml/minute; elbow arteriovenous fistulas: ≥ 5 mm and > 500 ml/minute). Mixed multivariable logistic regression modelling of the early ultrasound scan data was used to predict arteriovenous fistula non-maturation by 10 weeks and fistula failure at 6 months. A total of 333 arteriovenous fistulas were created during the study window (47.7% wrist, 52.3% elbow). By 2 weeks, 37 (11.1%) arteriovenous fistulas had failed (thrombosed), but by 10 weeks, 219 of 333 (65.8%) of created arteriovenous fistulas had reached maturity (60.4% wrist, 67.2% elbow). Persistently lower flow rates and venous diameters were observed in those fistulas that did not mature. Models for arteriovenous fistulas' non-maturation could be optimally constructed using the week 4 scan data, with fistula venous diameter and flow rate the most significant variables in explaining wrist fistula maturity failure (positive predictive value 60.6%, 95% confidence interval 43.9% to 77.3%), whereas resistance index and flow rate were most significant for elbow arteriovenous fistulas (positive predictive value 66.7%, 95% confidence interval 48.9% to 84.4%). In contrast to non-maturation, both models predicted fistula maturation much more reliably [negative predictive values of 95.4% (95% confidence interval 91.0% to 99.8%) and 95.6% (95% confidence interval 91.8% to 99.4%) for wrist and elbow, respectively]. Additional follow-up and modelling on a subset (n = 192) of the original SONAR cohort (the SONAR-12M study) revealed the rates of primary, assisted primary and secondary patency arteriovenous fistulas at 6 months were 76.5, 80.7 and 83.3, respectively. Fistula vein size, flow rate and resistance index could identify primary patency failure at 6 months, with similar predictive power as for 10-week arteriovenous fistula maturity failure, but with wide confidence intervals for wrist (positive predictive value 72.7%, 95% confidence interval 46.4% to 99.0%) and elbow (positive predictive value 57.1%, 95% confidence interval 20.5% to 93.8%). These models, moreover, performed poorly at identifying assisted primary and secondary patency failure, likely because a subset of those arteriovenous fistulas identified on ultrasound surveillance as at risk underwent subsequent successful salvage intervention without recourse to early ultrasound data. Although early ultrasound can predict fistula maturation and longer-term patency very effectively, it was only moderately good at identifying those fistulas likely to remain immature or to fail within 6 months. Allied to the better- than-expected fistula patency rates achieved (that are further improved by successful salvage), we estimate that a randomised controlled trial comparing early ultrasound-guided intervention against standard care would require at least 1300 fistulas and would achieve only minimal patient benefit. This trial is registered as ISRCTN36033877 and ISRCTN17399438. This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR135572) and is published in full in Health Technology Assessment; Vol. 28, No. 24. See the NIHR Funding and Awards website for further award information.

A systematic review of prediction models on arteriovenous fistula: Risk scores and machine learning approaches.

Failure-to-mature and early stenosis remains the Achille's heel of hemodialysis arteriovenous fistula (AVF) creation. The maturation and patency of an AVF can be influenced by a variety of demographic, comorbidity, and anatomical factors. This study aims to review the prediction models of AVF maturation and patency with various risk scores and machine learning models. Literature search was performed on PubMed, Scopus, and Embase to identify eligible articles. The quality of the studies was assessed using the Prediction model Risk Of Bias ASsessment (PROBAST) Tool. The performance (discrimination and calibration) of the included studies were extracted. Fourteen studies (seven studies used risk score approaches; seven studies used machine learning approaches) were included in the review. Among them, 12 studies were rated as high or unclear "risk of bias." Six studies were rated as high concern or unclear for "applicability." C-statistics (Model discrimination metric) was reported in five studies using risk score approach (0.70-0.886) and three utilized machine learning methods (0.80-0.85). Model calibration was reported in three studies. Failure-to-mature risk score developed by one of the studies has been externally validated in three different patient populations, however the model discrimination degraded significantly (C-statistics: 0.519-0.53). The performance of existing predictive models for AVF maturation/patency is underreported. They showed satisfactory performance in their own study population. However, there was high risk of bias in methodology used to build some of the models. The reviewed models also lack external validation or had reduced performance in external cohort.

Arteriovenous fistula for haemodialysis as a predictor of de novo heart failure in kidney transplant recipients.

The haemodynamic effects of a functioning haemodialysis arteriovenous fistula (AVF) can cause or exacerbate heart failure (HF). We investigated whether the presence of an AVF at the time of kidney transplant (KT) is associated with de novo HF. This was an observational cohort study including adult patients who received a KT in the West of Scotland between 2010 and 2020. We evaluated the risk and associations of pretransplant factors with de novo HF, alone and as a composite cardiovascular (CV) outcome (including non-fatal myocardial infarction, non-fatal stroke, de novo HF and CV death). Multivariable proportional hazards regression and sensitivity analyses were used to identify independent correlates of the outcomes. Among 1330 included patients, the incident rate of de novo HF after transplantation was 58/1000 person-years [95% confidence interval (CI) 50-67] in AVF patients (n=716) compared with 33/1000 person-years (95% CI 27-41) in non-AVF patients (n=614). De novo HF was associated with the presence of an AVF [adjusted hazard ratio (aHR) 2.14 (95% CI 1.40-3.26)], duration of dialysis [aHR 1.03/year increase (95% CI 1.01-1.04)], age at transplant [aHR 1.03/year increase (95% CI 1.02-1.05)], female sex [aHR 1.93 (95% CI 1.40-2.65)] and pretransplant diabetes [aHR 2.43 (95% CI 1.48-4.01)]. The presence of an AVF was also associated with the composite CV outcome [aHR 1.91 (95% CI 1.31-2.78)]. The presence of an AVF may be an underrecognized modifiable predictor of de novo HF posttransplantation.

Association of anesthetic modality and other variables on 1-year functional patency of cephalic-based arteriovenous fistulae.

ObjectivesSome studies suggest that regional (RA) provides better patency for arteriovenous fistula (AVF) for hemodialysis (HD) access as compared to Local (LA) and General Anesthesia (GA). This study evaluates the impact of anesthetic modality on long term fistula function at 12 months. MethodsA retrospective review of patients undergoing cephalic vein-based HD access in consecutive cases between 2014 and 2019 was conducted from five safety net hospitals. The primary endpoint was functional patency at 12 months. Subset analysis individually evaluated cephalic based lower forearm and wrist versus upper arm AVFs. Bivariate and multivariate logistic regression models evaluated the relationship between anesthetic modality and fistula function at 12 months. ResultsThere were 818 cephalic based fistulas created during the study period. The overall 12-month functional patency rate was 78.7%, including an 81.3% patency for upper arm AVF and 73.3% for wrist AVF (p=0.009). There was no statistically significant difference among patients with functional and nonfunctional AVFs at 12 months with respect to anesthetic modality when comparing regional, local, and general anesthesia (p=0.343). Multivariate regression analysis identified that history of AVF/AVG (OR 0.24, p=0.007), receiving intraoperative systemic anticoagulation (OR 2.49, p<0.001), and vein diameter (OR 1.85, p=0.039) as independently associated with AVF functional patency at 12 months. ConclusionThere was no association between anesthetic modality and functional patency of cephalic based-AVF at 12 months. Further studies are needed to better define which patients may benefit from regional anesthesia.

Arteriovenous fistula access for dialysis using vessels of the arm

Background: Site selection, configuration of the access and technical performance of operation are keys to a successful arteriovenous fistula (AVF) for haemodialysis. Objective: To evaluate the primary success rate and complications of AVF performed in Port Harcourt using vessels of the arm. Materials and Methods: This was a prospective cross-sectional study on the success rate of the Arteriovenous fistulas done using vessels of the arm in patients with End Stage Renal Disease (ESRD) undergoing dialysis across public and private health facilities in Port Harcourt. The study was conducted between March 1, 2017, and February 29, 2024. Preoperatively, using a duplex scan (and sometimes through clinical examination) with and without a tourniquet, the selected vein size was ≥ 2.5mm and the artery ≥2mm with a healthy wall and good flow. Parameters monitored were thrill and bruit intra-operatively, immediate, one- week and 6-8 weeks post-operative periods; the size of the vein intra-operatively, one -week and 6-8 weeks post-operatively. In addition, the patients were monitored for complications. Data were analyzed using statistical packages for social sciences (SPSS) version 25. Th demographic data and medical information were summarized using descriptive statistics (mean, median, frequency percentage and standard deviation) as appropriate. Result: There were 87 patients during the period under review. The age range was 14-85years with mean age of 54 ± 6.4 years. Of these, 18 (20.69%) were females, and 69 (79.31%) were males; 92 AVFs were done in 87 patients (87 primary and 5 repeat) with ESRD for dialysis; 69 (75%) Brachiocephalic (BC) and 23 (25%) Brachiobasilic (BB)AVFs. The AVFs were primarily successful in 82 cases (94.25%), with 5 primary failures (5.75%), and a total of 5 repeat AVFs within this period, excluding secondary failures. Complications were 1 (1.15%) upper limb oedema, 6 (6.90%) delayed wound healing, 4 (4.60%) cases of seroma, 1 (1.15%) case of steal syndrome, 4 (4.60%) cases of spontaneous thrombosis and 3 (3.45%) cases of superficial wound infection. Conclusion: The primary success rate of AVF for dialysis in Port Harcourt using vessels of the arm is quite good with few complications.

Knowledge, attitude, and practice toward arteriovenous fistulas for hemodialysis among nurses.

The effective management of vascular access (VA) is pivotal in hemodialysis (HD) care, with nurses assuming a key role in this crucial process. Nonetheless, there is a noticeable gap in our understanding of the knowledge, attitude, and practice (KAP) of nurses concerning arteriovenous fistulas (AVF) for HD. This study aimed to investigate the KAP of nurses in this domain. This multi-center cross-sectional study was conducted in 42 hospitals from April 11, 2023, to June 11, 2023. Participating nurses completed a self-administered questionnaire providing demographic and KAP information. Structural equation modeling (SEM) was utilized to assess the interrelationship between KAP. A total of 450 valid questionnaires were included in the analysis. The knowledge, attitude, and practice scores were 12.70 ± 1.42 (84.6%, possible score: 0-15), 44.37 ± 2.76 (88.7%, possible score: 10-50), and 56.73 ± 6.61 (87.3%, possible score: 13-65), indicating that adequate knowledge, positive attitude, and proactive practice. Knowledge had a direct influence on both attitude (β = 0.42, 95% CI: 0.24-0.59, p < 0.001) and practice (β = 0.58, 95% CI: 0.20-0.96, p = 0.003), and it also indirectly influenced practice through attitude (β = 0.45, 95% CI: 0.24-0.65, p < 0.001). The findings revealed that HD nurses exhibited adequate knowledge, positive attitude, and proactive practice concerning AVF for HD. Notably, their level of knowledge directly influenced both their attitudes and practices, while also exerting an indirect influence on the latter.

Role of Doppler Evaluation in Assessing the Maturation of the Arteriovenous Fistula for Hemodialysis: An Observational Study.

Introduction Arteriovenous fistulas (AVFs) are the preferred type of vascular access for hemodialysis due to their lower risk of complications. This study aimed to determine the role of Doppler evaluation in assessing AVF. Materials and methods We conducted an 18-month prospective observational study of 33 hemodialysis patients who underwent a procedure for the creation of AVF at the Department of Radio-Diagnosis at Sri Devaraj Urs Academy of Higher Education and Research.Patients were evaluated using color Doppler ultrasound. Participants underwent a careful history and clinical examination to diagnose the disease. All relevant parameters were documented in a structured study proforma. AVF maturation was assessed postoperatively at four weeks using Doppler ultrasound color flow evaluation by looking for vascular components (flow volume, vein, and arterial diameter). Data were analyzed using CoGuide V 1.0.3 Statistical Software (CoGuide, Bangalore, India). Results A total of 33 patients, with a mean age of 54.6 ± 7.8 years, were evaluated. Of the 33 participants, 24 (72.7%) were male, and nine (27.3%) were female. The majority (47%, n=16) of participants had diabetes mellitus, eight (24%) had hypertension, and 10 (29%) had both diabetes mellitus and hypertension. A brachiocephalic fistula was created in 45.5% of participants, and 33.33% had radiocephalic anastomoses. Five participants were diagnosed with AVF complications: two had a pseudoaneurysm, and three had a cephalic vein thrombus. Clinical and demographic characteristics (age, vascular components, and complications) were not significantly related to AVF maturation. Conclusions Doppler ultrasound plays an important role in selecting vessels for AVF preoperatively and assessing AVF maturation postoperatively, thus reducing the primary fistula failure rate. The findings suggest that Doppler evaluation can be a reliable tool for assessing AVF maturation and predicting surgical success, which could help healthcare providers make informed decisions about the best course of treatment for their patients. Continued research is warranted in this area to further understand the role of Doppler ultrasound in evaluating AVF surgery.

Endovascular Fistula Salvage for Preserving Arteriovenous Fistula Failure in Haemodialysis Patient: Tertiary Referral Hospital, a Single-Centre Experience

Abstract: Efficacy of endovascular intervention for the preservation of failing accesses is very important in hemodialysis patients. This study aimed to determine the efficacy of endovascular balloon angioplasty in preserving the patency of hemodialysis arteriovenous fistula (AVF) failure. This was a retrospective study of hemodialysis patients who received endovascular intervention due to access difficulties. A single-center study was created between January 2022 and June 2022. Fistulography was conducted on patients suspected of having access stenosis, and balloon angioplasty was performed in the same setting if stenosis of 50% was confirmed. Post-operative complications and access restenosis or failure were monitored. The results obtained 69 patients with hemodialysis access failure due to AVF stenosis, occlusion, and thrombosis that were admitted or referred to our hospital. The majority of patients were 40-60 years (50.7%); 88.4% patients were male and 11.6% were female, with a mean age of 56.3±11.6 (range, 18–77). The sites of AVF failure were brachiocephalic (81.1%) and radiocephalic (18.9%). There was no complication recorded. The procedure succes rate was 81.1%. In conclusion, endovascular balloon angioplasty is effective in restoring hemodialysis access patency. Recurrence is common, and interventions must be repeated. Keeping access open can save lives. Percutaneous transluminal angioplasty (PTA) can be used to achieve safely and successfully repair arteriovenous fistulas failure. Keywords: angioplasty; arteriovenous fistula; arteriovenous graft; hemodialysis

Point-of-Care Arterio-Venous Fistula Ultrasound in the Outpatient Hemodialysis Unit-A Survey on the Nurses' Perspective.

The preservation of complication-free arterio-venous fistulas (AVF) for long-term hemodialysis (HD) use is associated with better overall patient outcomes, which is why this is a current goal in any HD center. Point-of-care ultrasound (POCUS) for in-center AVF assessment has proven its benefits in the identification of vascular access (VA) complications and as an additional tool to avoid blind cannulation. The current study aims to assess the change in the HD nurses' perceptions regarding AVF POCUS use in the HD center. The nursing staff anonymously answered a Likert scale questionnaire with five questions related to various aspects of AVF POCUS utility shortly after the technique had been implemented and at a 5-year follow-up. The results showed an overall positive attitude toward this method, both at implementation and at follow-up, with no statistically significant score changes for four out of the five items assessed. However, we found a statistically significant reduction in the nurses' cannulation confidence scores at the 5-year follow-up (p < 0.01). Overall, AVF POCUS implementation is regarded as a useful tool, with major benefits both for the patient and for the medical team. The current study results aim to support the introduction of AVF POCUS assessment as a standard practice from the nursing staff's viewpoint. This study was not registered.

Early Ultrasound Surveillance of Newly-Created Hemodialysis Arteriovenous Fistula

IntroductionWe assess if ultrasound surveillance of newly-created arteriovenous fistulas (AVFs) can predict non-maturation sufficiently reliably to justify randomised controlled trial (RCT) evaluation of ultrasound-directed salvage intervention. MethodsConsenting adults underwent blinded fortnightly ultrasound scanning of their AVF after creation, with scan characteristics that predicted AVF non-maturation identified by logistic regression modelling. ResultsOf 333 AVFs created, 65.8% matured by 10 weeks. Serial scanning revealed that maturation occurred rapidly, whereas consistently lower fistula flow rates and venous diameters were observed in those that did not mature. Wrist and elbow AVF non-maturation could be optimally modelled from the week four ultrasound parameters alone, but with only moderate positive predictive values (wrist, 60.6% (95% CI 43.9 – 77.3); elbow, 66.7% (48.9 - 84.4)). Moreover, 40 (70.2%) of the 57 AVFs that thrombosed by week 10 had already failed by the week 4 scan, thus limiting the potential of salvage procedures initiated by that scan’s findings to alter overall maturation rates.Modelling of the early ultrasound characteristics could also predict primary patency failure at 6 months, but that model performed poorly at predicting assisted primary failure (those AVFs thatfailed despite a salvage attempt), partly because patency of at-risk AVFs was maintained by successful salvage performed without recourse to the early scan data. ConclusionsEarly ultrasound surveillance may predict fistula maturation, but is likely, at best, to result in only very modest improvements in fistula patency. Power calculations suggest that an impractically large number of participants (>1700) would be required for formal RCT evaluation.

Predicting factors for early failure of vascular access in hemodialysis patients.

This study aimed to investigate the incidence of early failure of vascular access for hemodialysis, and determine which factors measured in duplex ultrasound study could predict early failure. We performed a retrospective review of patients who underwent arteriovenous fistula (AVF) or arteriovenous graft (AVG) creation for hemodialysis between September 2019 and January 2023. Early failure was defined as any event that required surgical or endovascular intervention within 6 months following AVF or AVG creation. A total of 189 patients were included. Early failure occurred in 36 patients (19.0%), which included 22 AVFs and 14 AVGs. In the patients who underwent AVF, the preoperative venous diameter, postoperative venous and arterial diameters, and flow volume of AVF all were significantly smaller in the early failure group compared to the patent group. In AVG, the preoperative venous diameter was the only parameter that differed between the 2 groups. A sonographic score was defined based on these factors. In a multivariable analysis, male sex, a previous history of AVF or AVG creation, and sonographic score were found to be significantly associated with early failure. The postoperative venous diameter in AVF and the preoperative venous diameter in AVG were highly predictive of early failure (areas under the curves 0.92 and 0.82, respectively). Venous diameter measured 6 weeks following AVF operation and preoperative venous diameter in AVG were highly predictive of early failure among the duplex ultrasound parameters. Surveillance strategies in the early phase following vascular access creation can be based on these factors.

Role of drug coated balloon angioplasty in treatment of recurrent dysfunctional arteriovenous fistulae for hemodialysis.

Role of drug coated balloon angioplasty in treatment of recurrent dysfunctional arteriovenous fistulae for hemodialysis.

Evaluation of arteriovenous fistula for hemodialysis with a new generation digital stethoscope: a pilot study.

The management of complications of arteriovenous fistula (AVF) for hemodialysis, principally stenosis, remains a major challenge for clinicians with a substantial impact on health resources. Stenosis not infrequently preludes to thrombotic events with the loss of AVF functionality. A functioning AVF, when listened by a stethoscope, has a continuous systolic-diastolic low-frequency murmur, while with stenosis, the frequency of the murmur increases and the duration of diastolic component decreases, disappearing in severe stenosis. These evidences are strictly subjective and dependent from operator skill and experience. New generation digital stethoscopes are able to record sound and subsequently dedicated software allows to extract quantitative variables that characterize the sound in an absolutely objective and repeatable way. The aim of our study was to analyze with an appropriate software sounds from AVFs taken by a commercial digital stethoscope and to investigate the potentiality to develop an objective way to detect stenosis. Between September 2022 and January 2023, 64 chronic hemodialysis (HD) patients were screened by two blinded experienced examiners for recognized criteria for stenosis by Doppler ultrasound (DUS) and, consequently, the sound coming from the AVFs using a 3M™ Littmann® CORE Digital Stethoscope 8570 in standardized sites was recorded. The sound waves were transformed into quantitative variables (amplitude and frequency) using a sound analysis software. The practical usefulness of the core digital stethoscope for a quick identification of an AVF stenosis was further evaluated through a pragmatic trial. Eight young nephrologist trainees underwent a simple auscultatory training consisting of two sessions of sound auscultation focusing two times on a "normal" AVF sound by placing the digital stethoscope on a convenience site of a functional AVF. In 48 patients eligible, all sound components displayed, alone, a remarkable diagnostic capacity. More in detail, the AUC of the average power was 0.872 [95% CI 0.729-0.951], while that of the mean normalized frequency was 0.822 [95% 0.656-0.930]. From a total of 32 auscultations (eight different block sequences, each one comprising four auscultations), the young clinicians were able to identify the correct sound (stenosis/normal AVF) in 25 cases, corresponding to an overall accuracy of 78.12% (95% CI 60.03-90.72%). The analysis of sound waves by a digital stethoscope permitted us to distinguish between stenotic and no stenotic AVFs. The standardization of this technique and the introducing of data in a deep learning algorithm could allow an objective and fast method for a frequent monitoring of AVF.

Posttraumatic arteriovenous fistula of the lower extremity and the pathological characteristic—case series and literature review

Abstract The clinical presentation, treatment history, and outcomes of two patients with posttraumatic arteriovenous fistula (PTAVF) were analyzed and compared with the pathological tissues of patients with hemodialysis arteriovenous fistula (HAVF). A search of the biomedical literature database (PubMed), using the keywords “ lower extremity” and “PTAVF,” was conducted to obtain results and review the data. Postoperative histological analysis of patients with PTAVF showed differences from that of HAVF. The literature screening and analysis revealed that PTAVF is a chronic progressive process, with 70% of patients diagnosed after 3 months. The choice of treatment revealed that 20% of patients had severe complications and all were treated endovascularly. Due to the abnormal fistula of PTAVF and its specific histopathological features, the disease is not self-limiting. It is unwise to wait for PTAVF to cause “failure.” We recommend early and timely cure of this disease by surgery to avoid serious complications.

USE of IMplanting the Biotronik PassEo-18 Lux drug coated balloon to treat failing haemodialysis arteRiovenous FIstulas and grafts (SEMPER FI Study)

Background: Plain old balloon angioplasty has been the mainstay of treatment for arteriovenous fistula (AVF) stenoses. Recent studies suggest that drug coated balloons (DCB) may significantly reduce re-intervention rates on native and recurrent lesions. The Passeo-18 Lux DCB (Biotronik AG, Buelach, Switzerland) is packaged with a 3.0 µg/mm2 dose of paclitaxel. The hypothesis is that its use provides better target lesion primary patency (TLPP), primary assisted patency (PP), secondary patency (SP) rates and reduces the number of visits for re-intervention in a cohort of patients with stenotic AVF and arteriovenous grafts (AVGs). Methods: The USE of IMplanting the Biotronik PassEo-18 Lux DCB to treat failing haemodialysis arteRiovenous FIstulas and grafts trial (SEMPER FI) was a prospective double-centre, multi-investigator, non-consecutive, non-blinded single-arm study investigating the efficacy and safety of the Passeo-18 Lux DCB in patients with stenotic AVF/AVG lesions between January 2021 and January 2022. Patient demographics, clinical characteristics, vascular access history, operative indications, details and outcomes were collected prospectively. TLPP, circuit access primary patency (CAP), PP, SP and deaths 6- and 12-months post-intervention were studied. Results: Ninety-one patients with 110 lesions were recruited across the two centres. 62.6% ( n = 57) were male with a median age of 63.5 years (SD = 10.5). 62.6% ( n = 57) were taking anti-platelets. Eighty-five AVFs and six AVGs were treated. 60% ( n = 54) of AVFs intervened were radiocephalic. 52.7% ( n = 58) of targeted lesions were juxta-anastomotic stenosis (JAS) and one-third ( n = 33) at the AVF/AVG outflow. 70.9% ( n = 78) of lesions were recurrent. Median time from last intervention was 219 days. 78% of target lesions ( n = 85) and circuits ( n = 70) were patent at 6-months, of which 96.7% ( n = 87) of those requiring assisted intervention were patent. Conclusion: This study shows that the Passeo-18 Lux DCB can be an effective and safe tool in the treatment of failing haemodialysis AVFs/AVGs.

Creating hemodialysis autogenous access in children and adolescents

ObjectiveEnd-stage renal disease (ESRD) in childhood and adolescence is rare, with relatively few published reports of pediatric ESRD vascular access. This study analyzes a 10-year experience creating arteriovenous fistulas (AVFs) in children and adolescents. Our goal is to review our strategy for creating functional autogenous vascular access in younger patients and report our results. MethodsWe retrospectively reviewed data and outcomes for consecutive vascular access patients aged ≤19 years during a 10-year period. Each patient had preoperative vascular ultrasound mapping by the operating surgeon in addition to physical examination. A distal forearm radiocephalic AVF was the first access choice when feasible, and a proximal radial artery inflow AVF was the next option. Demographic data, inflow artery, venous outflow target, and required transposition vs direct AVFs were variables included in the analysis. Primary and cumulative patency were calculated by Kaplan-Meier analysis. ResultsThirty-seven AVFs were created in 35 patients. No grafts were used. Ages were 6 to 19 years (mean, 15 years), and 20 were male. Causes of ESRD included glomerular disease (n = 18) and urinary obstruction or reflux (n = 7), among others. Three had previous AVFs, and 10 were obese. The proximal radial artery supplied AVF inflow in 25 patients and the brachial artery in only seven. Eleven individuals required a transposition and one a vein translocation to the contralateral arm. No patients developed hand ischemia, although two later required banding procedures for high flow. Eleven patients had successful transplants. A single patient died, unrelated to the vascular access. Five AVFs failed. Of these, two had new successful AVFs created, two regained renal function, one was transplanted, and one declined other procedures. Primary and cumulative patency rates were 75% and 85% at 12 months, 70% and 85% at 24 months, and 51% and 85% at 36 months, respectively. Median follow-up was 16 months. ConclusionsCreating an AVF for hemodialysis is a successful vascular access strategy for pediatric and adolescent patients. Proximal radial artery AVFs provided safe and functional access when a distal AVF was not feasible. Cumulative AVF patency was 85% at 36 months.

Endovascular Treatment of Subclavian Artery Occlusion by Surgical Exposure of the Proximal Brachial Artery at the Side of an Arteriovenous Fistula.

A 76-year-old man undergoing hemodialysis complained of pain and discoloration of his right finger. The hemodialysis arteriovenous fistula was in the right upper extremity. Ultrasonography showed right subclavian artery occlusion. The lesion could not be approached from the lower extremity and olecranon artery. Thus, we performed the procedure after exposing the proximal brachial artery. We were able to recanalize the subclavian artery and restore blood flow to the right upper extremity. When the lesion is on the side of the arteriovenous fistula and approaching from the lower extremity is difficult, exposure of the proximal brachial artery can be considered.

Role of drug coated balloon angioplasty in treatment of recurrent dysfunctional arteriovenous fistulae for hemodialysis

Objective This study aimed to evaluate the safety, clinical benefits, and patency outcomes of using paclitaxel drug-coated balloons (DCBs) for the treatment of recurrent dysfunctional arteriovenous fistulae (AVF) in hemodialysis patients. Study design A nonrandomized clinical trial was conducted involving 20 patients who had previously undergone percutaneous transluminal angioplasty (PTA) for failing or failed AVF. Patients were assessed based on clinical criteria, and interventions were performed using paclitaxel-coated balloons. Clinical outcomes, including thrill, bruit, and hemodialysis function, were evaluated, and duplex assessments were conducted after 3 and 6 months to determine recurrent stenosis. Statistical analysis was carried out using SPSS. Results The study included 20 end-stage renal disease (ESRD) patients with a mean age of 49.4±17 years. After 2 weeks’ postintervention, all patients had adequate bruit, 16 (80%) patients had adequate thrill, and 19 (95%) patients had adequate hemodialysis. After 6 months, 70% of patients exhibited adequate thrill, while adequate bruit, and hemodialysis were observed in 75% of patients. Duplex assessments showed minimal recurrent stenosis after 3 and 6 months, with only a few cases of new stenotic lesions. Postoperative complications were infrequent, including one unrelated death, and a small number of central venous occlusions and infections. The study indicated a significantly improved efficacy of drug-coated balloon angioplasty over traditional angioplasty in maintaining AVF patency. Conclusion Paclitaxel drug-coated balloons offer a promising approach for treating recurrent dysfunctional arteriovenous fistulae in hemodialysis patients. The study demonstrated favorable clinical outcomes, reduced restenosis rates, and improved patency compared with traditional angioplasty.

Possibility and predictors of surgical salvage of infected mature arteriovenous fistula for hemodialysis

Background Infection in arteriovenous fistula (AVF) is a common complication in patients with end-stage renal disease (ESRD) requiring dialysis. The standard management includes ligation of the AVF to prevent the progression of septicemia. Till now, there is limited evidence on the effectiveness and possibility of salvage of infected AVFs. Aim To evaluate the effectiveness and safety of salvage of infected mature autogenous AVF. Methods This prospective study was conducted at the Fayoum University Hospital from September 2015 to April 2023. We included patients with dysfunctional and functioning infected AVF. Patients with infected synthetic grafts and immature infected AVFs were excluded. We aimed to excise the infected part of the vein wall and surrounding tissues to restore fistula patent and functioning after direct vein repair. We followed-up with all patients for 1 year and examined the repaired AVFs for patency and the possibility of re-infection. Tissue cultures were obtained to identify the commonest responsible organism and the recommended antibiotics. Results A total of 46 patients with infected AVFs were included. At the end of the follow-up period, 11 patients were ligated, and 35 underwent AVF salvage procedures. 19 cases experienced some complications: 5 cases had hematoma required surgical intervention, 2 cases had hematoma managed conservatively, 2 patients had wound dehiscence, 3 patients required hybrid angioplasty for acute failed AVF, and 7 cases required angioplasty for failing AVF. Conclusion When performed correctly and with expert hands, salvage of infected mature AVFs seems possible with excellent efficacy and high patency for up to 1 year.