High Plasma Angiopoietin-2 Levels Predict the Need to Initiate Dialysis within Two Years in Patients with Chronic Kidney Disease.

Volume status, congestion, endothelial activation, and injury all play roles in glomerular filtration rate (GFR) decline. In this study, we aimed to determine whether the plasma endothelial and overhydration markers could serve as independent predictors for dialysis initiation in patients with chronic kidney disease (CKD) 3b-5 (GFR < 45 mL/min/1.72 m2) and preserved ejection fraction. A prospective, observational study in a single academic center was conducted from March 2019 to March 2022. Plasma levels of angiopoietin (Ang)-2, Vascular Endothelial Growth Factor-C (VEGF-C), Vascular Cell Adhesion Molecule-1 (VCAM-1), Copeptin (CPP), beta-trace protein (BTP), brain natriuretic peptide (BNP), and cardiac troponin I (cTnI) were all measured. Lung ultrasound (US) B-lines, bioimpedance, and echocardiography with global longitudinal strain (GLS) were recorded. The study outcome was the initiation of chronic dialysis (renal replacement therapy) during 24 months of follow-up. A total of 105 consecutive patients with a mean eGFR of 21.3 mL/min/1.73 m were recruited and finally analyzed. A positive correlation between Ang-2 and VCAM-1 and BTP was observed. Ang-2 correlated positively with BNP, cTnI, sCr, E/e', and the extracellular water (ECW)/intracellular water (ICW) ratio (ECW/ICW). After 24 months, a deterioration in renal function was observed in 47 patients (58%). In multivariate regression analysis, both VCAM-1 and Ang-2 showed independent influences on risk of renal replacement therapy initiation. In a Kaplan-Meier analysis, 72% of patients with Ang-2 concentrations below the median (3.15 ng/mL) survived without dialysis for two years. Such an impact was not observed for GFR, VCAM, CCP, VEGF-C, or BTP. Endothelial activation, quantified by plasma levels of Ang-2, may play a key role in GFR decline and the need for dialysis initiation in patients with CKD 3b, 4, and 5.

A randomized multicenter trial on a lung ultrasound-guided treatment strategy in patients on chronic hemodialysis with high cardiovascular risk.

Lung congestion is a risk factor for all-cause and cardiovascular mortality in patients on chronic hemodialysis, and its estimation by ultrasound may be useful to guide ultrafiltration and drug therapy in this population. In an international, multi-center randomized controlled trial (NCT02310061) we investigated whether a lung ultrasound-guided treatment strategy improved a composite end point (all-cause death, non-fatal myocardial infarction, decompensated heart failure) vs usual care in patients receiving chronic hemodialysis with high cardiovascular risk. Patient-Reported Outcomes (Depression and the Standard Form 36 Quality of Life Questionnaire, SF36) were assessed as secondary outcomes. A total of 367 patients were enrolled: 183 in the active arm and 180 in the control arm. In the active arm, the pre-dialysis lung scan was used to titrate ultrafiltration during dialysis and drug treatment. Three hundred and seven patients completed the study: 152 in the active arm and 155 in the control arm. During a mean follow-up of 1.49 years, lung congestion was significantly more frequently relieved in the active (78%) than in the control (56%) arm and the intervention was safe. The primary composite end point did not significantly differ between the two study arms (Hazard Ratio 0.88; 95% Confidence Interval: 0.63-1.24). The risk for all-cause and cardiovascular hospitalization and the changes of left ventricular mass and function did not differ among the two groups. A post hoc analysis for recurrent episodes of decompensated heart failure (0.37; 0.15-0.93) and cardiovascular events (0.63; 0.41-0.97) showed a risk reduction for these outcomes in the active arm. There were no differences in patient-reported outcomes between groups. Thus, in patients on chronic hemodialysis with high cardiovascular risk, a treatment strategy guided by lung ultrasound effectively relieved lung congestion but was not more effective than usual care in improving the primary or secondary end points of the trial.

Carotid artery tortuosity may pose a problem during insertion of the tunneled catheter for hemodialysis.

Tortuosity of the carotid artery is usually an asymptomatic vascular abnormality and is discovered accidentally during cerebral angiography. These vascular changes may aggravate surgical procedures in the neck region. We described a technique of permanent catheter insertion in patients with renal graft failure in whom renal replacement therapy was necessary. Severe tortuosity of cervical arteries may make this procedure more difficult, necessitating a special technique, that is, full image monitoring.

The impact of location and patency of the arteriovenous fistula on quality of life of kidney transplant recipients.

BACKGROUND: Arteriovenous fistulae (AVFs) may remain patent after kidney transplantation (KTx), contributing to maladaptive cardiac remodeling. The flow in AVFs is associated with the diameter of its vessels and thus with the AVF location. The main objective of this study is to assess the influence of AVF location and its patency on the self-reported quality of life (QOL) of kidney transplant recipients (KTRs) with past history of hemodialysis. METHODS: To gain clinical data, during a scheduled visit, 353 KTRs were asked to fill out an anonymous questionnaire. From this group, 284 respondents were found eligible for analysis. The outcome was defined as prevalence of symptoms and health status, measured with the Left Ventricular Dysfunction-36 (LVD-36) Questionnaire in symptomatic patients. RESULTS: The hemodialysis patients (n = 243) were divided into two groups according to AVF location, i.e., DAVF - distally located AVF - (n = 174) and PAVF - proximally located AVF - (n = 69). The proportion of patients with heart failure (HF) was higher in PAVF group (24% vs. 12%, p = 0.0482). In the multivariable regression, PAVF, serum creatinine levels, and the presence of HF or coronary artery disease (CAD) remained independent predictors of lower functional capacity. Among patients with heart disease, the presence of active AVF was independently associated with worse functional outcome (higher LVD-36 scores). CONCLUSIONS: The influence of persistent PAVF in KTRs seems to be unfavorable, especially when coexisting with CAD or HF. Abbreviations: AVF arteriovenous fistula; BMI body mass index; CAD coronary artery disease; D-AVF distally-located arteriovenous fistula; EC exercise capacity; HD hemodialysis; HF heart failure; KTx kidney transplantation; KTR kidney transplant recipient; LVD-36 Left Ventricle Disfunction - 36; LVEF left ventricle ejection fraction; LVH left ventricle hypertrophy; NYHA New York Heart Association; P-AVF proximally located arteriovenous fistula; PD peritoneal dialysis; PRO patient-reported outcomes; QOL quality of life.

Dialysis Catheter Insertion with Extended Ultrasound Monitoring.

INTRODUCTION: Dialysis catheter insertion is a routine procedure performed when there is necessity of urgent renal replacement therapy initiation. Due to limited access, higher costs, and long waiting times for fluoroscopy, alternative visualization methods are introduced into clinical practice. One of the most promising is transthoracic echocardiographic monitoring of guide-wire introduction. OBJECTIVE: The feasibility of the technique was verified by nephrologists inserting dialysis catheters. METHODS: A single center prospective trial was performed (NCT03727581). Introduction of guide-wire was monitored with ultrasound to confirm correct position of the wire in the inferior vena cava (IVC) or right atrium (RA). The study group included 30 patients, 19 males and 11 females, 25-83 years old. RESULTS: It was possible to obtain a good picture of IVC in the majority of patients. In 20 (66.7%) cases, IVC view was excellent; in 9 (30%) cases, was fair; and in 1 (3.3%) patient, we failed to visualize IVC. The guide-wire was identified in IVC in 12 (42.8%) patients, in another 9 (32.1%) patients guide-wire was visible in IVC after withdrawing and advancing it, and in RA in 6 (21.4%) patients. Catheters were successfully placed in 29 (96.7%) patients. CONCLUSIONS: Detection of the guide-wire confirms correct course of the procedure and increases the safety of catheter insertion without fluoroscopy.

Application of strain and other echocardiographic parameters in the evaluation of early and long-term clinical outcomes after cardiac surgery revascularization.

BACKGROUND: Coronary artery bypass graft (CABG) surgery is an effective therapeutic strategy for coronary heart disease (CHD). Myocardial longitudinal strain echocardiography with 2D speckle tracking could obtain ventricular function with better accuracy and reliability than the left ventricular ejection fraction. The aim of the study was to assess changes in left ventricular function in patients before and after surgical revascularization for a 24-month period of observation, using echocardiography with speckle tracking strain imaging. We searched for echocardiographic predictors of poor early and long-term outcome after CABG. METHODS: We enrolled 69 patients scheduled for elective coronary bypass grafting. Patients were divided into groups based on pre-operative systolic and diastolic parameters, depending on the GLS value and the E' Lat and E/E' value. The correlation between these parameters and early and long-term outcomes was analyzed. RESULTS: Preoperative EF was preserved in 86, 95% (60) patients. Pre-operative reduced GLS was observed in 73.91% (51) of patients and severely reduced in 31.88% (22). In the first post-operative 6-month period, we observed a significant decrease in the GLS. The GLS was a predictor of early postoperative outcome for intubation time, the inotropes use and length of ICU stay. Diastolic dysfunction was a predictor of the greater inotrope requirements. CONCLUSIONS: Global longitudinal strain and diastolic dysfunction parameters are a good predictors of worse early outcome after CABG.

Dialysis-Related Parameters Influence Remodeling in the Venous Part of the Native Arteriovenous Fistula.

BACKGROUND: The aim of this study was to evaluate the association of hemodynamic parameters related to hemodialysis and antropometric parameters of patients with changes in the venous part of the arteriovenous fistula (AVF) at points of needling. METHODS: Two hundred forty-two hemodialysis (HD) patients (60.3% men), with median age 65 (interquartile range [IQR] 56-75) years, on HD treatment for a median of 49 (IQR 20-88) months with functioning fistula were recruited for the study. The history of vascular access, comorbidity, antropometric (body mass index, body surface area, and body composition), and dialysis-related parameters were analyzed. The cross-sectional area of upper extremity vessels were measured using ultrasound and included 2 points: A (arterial point for blood aspiration) and V (venous point for returning the blood after purification). The difference between A and V (A-V) was calculated. RESULTS: The median cross-sectional area of A was larger than V (1.04 [IQR 0.58-1.7] vs. 0.74 cm2 [IQR: 0.41-1.39], P <0.0001). The median difference between A and V (A-V) was 0.17 cm2 and positively correlated with mean blood flow (Qb), effective Kt/V, and time of AVF use. Other analyzed factors had no influence on A-V. In the multivariate analysis, the independent factor increasing the difference (A-V) was mean blood flow measured during HD sessions. CONCLUSIONS: The needling and utilization of AVF for hemodialysis may affect vein anatomy, namely causing dilatation at the arterial point and narrowing at venous point of AVF. We suggest that blood pump velocity of the dialysis machine may have an impact on these changes, but practical importance of these findings has to be elucidated. The significance of (A-V) factor in the prognosis of fistula complications should be further studied and confirmed in the prospective trials.

The snuffbox fistula should be preferred over the wrist arteriovenous fistula.

OBJECTIVE: The snuffbox arteriovenous fistula (SBAVF) is the most distal native vascular access. Although published data show a favorable outcome, the SBAVF is not strongly recommended by the guidelines. The present study compared the patency of SBAVFs and wrist AVFs (WAVFs). METHODS: All 416 AVFs created by the same nephrologist from March 2006 to October 2014 were reviewed. From 416 procedures, 47 SBAVFs and 77 WAVFs with vessels suitable for a SBAVF were selected. RESULTS: Although vessel diameters used for construction of the SBAVFs were smaller than those used for WAVFs, the outcome of vascular access was similar. At 18 months, primary patency was 72% for SBAVF and 65% for WAVF (P = .48), and secondary patency was 93% for SBAVF and 94% for WAVF (P = .89). CONCLUSIONS: In our experience, a SBAVF performs as well as a WAVF up to 18 months after creation. We suggest favoring SBAVF, especially in young patients without comorbidities, as the primary vascular access.

Efficacy of a remote web-based lung ultrasound training for nephrologists and cardiologists: a LUST trial sub-project.

Within the framework of the LUST trial (LUng water by Ultra-Sound guided Treatment to prevent death and cardiovascular events in high-risk end-stage renal disease patients), the European Renal and Cardiovascular Medicine (EURECA-m) working group of the European Renal Association-European Dialysis Transplant Association established a central core lab aimed at training and certifying nephrologists and cardiologists participating in this trial. All participants were trained by an expert trainer with an entirely web-based programme. Thirty nephrologists and 14 cardiologists successfully completed the training. At the end of training, a set of 47 lung ultrasound (US) videos was provided to trainees who were asked to estimate the number of B-lines in each video. The intraclass correlation coefficient (ICC) for the whole series of 47 videos between each trainee and the expert trainer was high (average 0.81 ± 0.21) and >0.70 in all but five cases. After further training, the five underperforming trainees achieved satisfactory agreement with the expert trainer (average post-retraining ICC 0.74 ± 0.14). The Bland-Altman plot showed virtually no bias (difference between the mean 0.03) and strict 95% limits of agreement lines (-1.52 and 1.45 US B-lines). Only four cases overlapped but did not exceed the same limits. Likewise, the Spearman correlation coefficient applied to the same data series was very high (r = 0.979, P < 0.0001). Nephrologists and cardiologists can be effectively trained to measure lung congestion by an entirely web-based programme. This web-based training programme ensures high-quality standardization of US B-line measurements and represents a simple, costless and effective preparatory step for clinical trials targeting lung congestion.

Balloon Dilatation for Removal of an Irretrievable Permanent Hemodialysis Catheter: The Safest Approach.

Long-term hemodialysis catheter dwell time in the central vein predisposes to fibrin sheath development, which subsequently causes catheter malfunction or occlusion. In very rare cases, the catheter can be overgrown with fibrin and rigidly connected with the vein or heart structures. This makes its removal almost impossible and dangerous because of the possibility of serious complications, namely vein and heart wall perforation, bleeding, or catheter abruption in deep tissues. We describe two cases in which standard retrieval of long-term catheters was not possible. Balloon dilatation of catheter lumens was successfully used to increase the catheter diameter with simultaneous tearing of the fibrin sheath surrounding it. This allowed the catheter to be set free safely. Based on this experience, we present recent literature and our point of view.

External dilator-assisted banding for high-flow hemodialysis arteriovenous fistula.

Creation of arteriovenous fistula (AVF) may lead to left ventricle hypertrophy and predispose for development or worsening of heart failure. It was postulated to reduce access blood flow if exceeded 2 L/min or cardiac index was higher than 3.0 L/min/m(2). Numbers of techniques decreasing flow were described. The major disadvantage was the complexity of procedure and necessity of intraoperative flow measurement needed to establish desired flow. The technique of dilator-assisted banding with no endovascular catheterization is presented. After blunt dissection non absorbable thread was placed around vessel and tied over the dilator. Then the dilator was gently removed and blood flow was confirmed by palpation. We performed 12 banding procedures. Mean brachial blood flows were 3733.2 ± 826.2 mL/min preoperatively and 1461.2 ± 337.7 mL/min after surgery. Mean flow reduction was 2272.2 ± 726.9 mL/min. The external dilator-assisted banding is a feasible method for vascular access flow reduction without necessity of endovascular catheterization.

Use of Plastic Needles for Early Arteriovenous Fistula Cannulation.

BACKGROUND: The native arteriovenous fistula (AVF) needs maturation before it can be used. Needling done before time may result in haematoma formation, miscannulation or even access loss. METHODS: This retrospective study included 20 patients with AVFs punctured with fluoroplastic dialysis catheters within 30 days after access creation and 19 historical controls. RESULTS: The time to first puncture was 2-29 days for the study group and 1-26 days for the control group. The incidences of haematoma were 16.7 and 48 per 1,000 dialysis sessions for plastic and metal needles, respectively. Estimated primary functional fistula survival at 3, 6 and 12 months were 95, 90 and 74% for the study group and 79, 67 and 60% for the control group (p = 0.106), respectively. CONCLUSIONS: Use of plastic needles enables safe AVF cannulation. If applied judiciously, it can minimize or even avoid catheter use.

[Vascular access in diabetic patients. Are these patients "difficult"?]. / Dostep naczyniowy u chorych na cukrzyce. Czy sa to chorzy problematyczni?

Diabetics with stage V chronic kidney disease (CKD) on hemodialysis (HD) are considered as "difficult patients", because of problems with creation of the vascular access. There is controversy regarding the results and recommendations for preparation of the vascular access in these patients. The aim of this retrospective study was to evaluate the results of creating different types of arteriovenous fistula (AVFs) in consecutive series of patients starting dialysis treatment. The analysis was performed in 741 patients (385 females and 356 males), average age 61.4±7 years, who started dialysis treatment in our department between January 2005 and December 2012. Native AVFs were created in all patients. No patients received an AVF requiring synthetic graft material. The number of patients with diabetic nephropathy was 166 (22.4%). Among them, 30 (18%) had type 1 diabetes and 136 (82%) type 2. In this group the occurrence of calcification in the forearm artery was estimated on the basis of physical examination, Allan's test, Doppler ultrasound and forearm X-ray. In a subgroup of patients with atherosclerotic changes in the arterial system the frequency of failed AVFs was analyzed. These results were compared with the group without diabetes. The number of procedures necessary for successfu AVF creation and type of access was counted in both groups. The assessment of the procedure frequency and AVF location in diabetic and in non-diabetic patients was made by χ² test with Yates correction. In the group of 166 patients with diabetes, in 100 cases (60%) atherosclerotic changes in forearm arteries were observed. In a subgroup of 30 patients with type 1 diabetes atherosclerosis was observed in 17 adults (57%). In this subgroup creation of a suitable forearm AVF in the first procedure in 9 patients was possible and in the other 8 cases the atherosclerotic changes necessitated repeated procedures and were an important obstacle to create the AVF. In the subgroup of 136 patients with type 2 diabetes, atherosclerosis in the forearm artery was observed in 83 cases (61%). In this subgroup the creation of a native AVF was possible in 40 patients during the first procedure and in 43 cases additional intervention was needed, but only in 8 cases was atherosclerosis the cause of fistula failure. Generally, among 166 patients only in 16 cases (10%) did atherosclerosis present an important obstacle for AVF creation, but the number of necessary procedures to create one functioning AVF was significantly greater in this population (2 v 2.7, p=0.0001). A functioning AVF in patients with diabetes was found significantly frequently in the arm localization in comparison to non-diabetic patients (4.3 v 2%, p=0.0478). Atherosclerotic changes in forearm arteries in diabetic patients appear in 60% of hemodialysis patients and make it difficult to create an AVF only in 10% of diabetic patients, but it is possible to create a native AVF in 90% of diabetic patients, although this requires more procedures. In patients with diabetes, AVF in the wrist region should be preferred.

Consider use of a collateral venous circuit before abandoning the arteriovenous fistula--the experience of a complex vascular access case.

We describe a 65-year-old woman with diabetes on hemodialysis maintenance, with a number of complications associated with high-flow arteriovenous fistula (AVF, anastomosis between brachial artery and medial vein of the forearm) requiring an extended diagnostic and individual approach. The patient was admitted to our hospital because of pain, edema of the limb, hand ischemia, and infection caused by steal syndrome. To reduce fistula flow, banding of the proximal cephalic vein was performed. Simultaneously because of necrosis, amputation of the fifth finger was necessary. Following this procedure, the cephalic vein on the arm thrombosed. The fistula was patent through the collateral circuit, which was diagnosed in detail during the late course. A long course of antibiotics and sessions in a hyperbaric chamber allowed limb rescue. Single-needle dialysis was carried out because of problems in finding an appropriate second place. After an episode of bleeding from the puncture site caused by ulceration, we were forced to search for an alternative needling point. On the basis of ultrasound scans, an anatomic schema of the blood circuit was created. The fistula demonstrated flow from the brachial artery resulting in retrograde flow in the section of the cephalic vein distal to the anastomosis in the upper forearm. This was then seen to drain in an antegrade direction via the median vein of the forearm after the 2 vessels connected in the mid forearm. Using the diagram, 2 alternative places for needling were found and it allowed the adequate hemodialysis to be continued. Complex and complicated cases associated with native AVF could be resolved using simple diagnostic tools to preserve the fistula use for hemodialysis. Both clinical examination and ultrasound scan with the Doppler option appear to be valuable methods for finding the optimal cannulation place.

Severe Bullous Erysipelas/Cellulitis, Atypically Caused by Escherichia coli, in Kidney Transplant Recipient - Case Report and Review of Literature.

Erysipelas/cellulitis are severe skin infections that are especially dangerous for immunocompromised patients. The most common cause of these diseases is streptococcal infection, but sometimes they may be caused by other Gram-positive or negative bacteria or other factors. Proper diagnosis and treatment should be implemented accurately to prevent dangerous complications. We present a case of severe bullous erysipelas caused by Escherichia coli and discuss the diagnosis, differential diagnosis, and treatment of cellulitis in kidney transplant patients.

Outcomes of early cannulation arteriovenous graft versus PTFE arteriovenous graft in hemodialysis patients: A meta-analysis and systematic review.

Arteriovenous graft (AVG) is an alternative for hemodialysis (HD) patients with end-stage renal disease when their permanent vascular accesses fail. Since the last decades, the most widely used materials in these patients have been polytetrafluoroethylene (PTFE)-AVGs. Recently, several studies have reported that early cannulation (EC)-AVG can be an alternative to PTFE-AVG. This systematic review and meta-analysis aimed to compare the outcomes of EC-AVG and PTFE-AVG in HD patients. We searched the Ovid Embase, Ovid MEDLINE, and Cochrane Central Register of Controlled Trials for the relevant studies published from 01.01.2000 to 19.12.2022 by keywords and free words. All randomized controlled trials (RCTs) and observational cohort studies comparing EC-AVG with PTFE-AVG were included. Ten studies were included in analysis: one RCT, six retrospective cohort studies, and three prospective cohort studies. The results showed shorter cannulation intervals (four studies, 1116 participants: mean difference -23.62 days, 95% CI [-32.03, -15.21], p < 0.05) and less central venous catheter (CVC) usage (four studies, 733 participants: OR 0.20, 95% CI [0.04, 0.92], p < 0.05) for EC-AVG compared with PTFE-AVG, while comparable outcomes of primary patency (eight studies, 1712 participants: HR 0.89, 95% CI [0.70, 1.12]), primary assisted patency (five studies, 1355 participants: HR 1.13, 95% CI [0.70, 1.84]), secondary patency (nine studies, 1920 participants: HR 0.93, 95% CI [0.66, 1.31]), and infection risk (four studies, 640 participants: HR 1.12, 95% CI [0.48, 2.58]). When compared to PTFE-AVG in HD patients, EC-AVG seems to exhibit shorter cannulation intervals, less CVC usage, and comparable outcomes of graft patency, and infection risk.

The Influence of Healthy Habits on Cognitive Functions in a Group of Hemodialysis Patients.

(1) Background: Cognitive impairment (CI) is more prevalent in hemodialysis (HD) patients than in the general population. The purpose of this study was to examine if behavioral, clinical, and vascular variables are linked with CI in individuals with HD. (2) Methods: Initially, 47 individuals with chronic HD volunteered to participate in the trial, but only 27 patients ultimately completed the Montreal Cognitive Assessment (MoCA) and the Computerized Cognitive Assessment Tool (CompBased-CAT). We collected information on smoking, mental activities, physical activity (Rapid Assessment of Physical Activity, RAPA), and comorbidity. The oxygen saturation (rSO2) and pulse wave velocity (PWV; IEM Mobil-O-Graph) of the frontal lobes were measured. (3) Results: Significant associations were discovered between MoCA and rSO2 (r = 0.44, p = 0.02 and r = 0.62, p = 0.001, right/left, respectively), PWV (r = -0.69, p = 0.0001), CCI (r = 0.59, p = 0.001), and RAPA (r = 0.72, p = 0.0001). Those who actively occupied their time during dialysis and non-smokers achieved higher cognitive exam results. A multivariate regression study demonstrated that physical activity (RAPA) and PWV had separate effects on cognitive performance. (4) Conclusions: Cognitive skills are related to inter-dialysis healthy habits (physical activity, smoking) and intra-dialysis activities (tasks and mind games). Arterial stiffness, oxygenation of the frontal lobes, and CCI were linked with CI.

Radial Artery Deviation and Reimplantation (RADAR) to Accelerate the Maturation of Radial-Cephalic Fistulas for Hemodialysis in Patients with End-Stage Renal Disease.

BACKGROUND: The most common form of vascular access for hemodialysis is a native arteriovenous fistula, which connects the site of the artery to the end of the vein. The maturation process of the fistula plays a crucial role in the establishment of a functional vascular access. Radial artery stenosis is among the potential causes of maturation failure. In these cases, improving the fistula's blood flow may be difficult, as traditional surgical reanastomosis and endovascular intervention frequently fail. Radial artery deviation and reimplantation (RADAR) is a novel and effective technique for creating primary fistulas with a high patency rate. The main disadvantage of this procedure is the ligation of the radial artery and the subsequent known consequences. METHODS: To accelerate maturation, we used RADAR as a secondary approach in three patients with radial artery stenosis and maturation failure. RESULTS: In all patients after surgery, we observed a significant increase in fistula blood flow. Two patients used fistulas for hemodialysis after surgery. We describe the image diagnosis, procedure, and benefits of this method. CONCLUSIONS: The RADAR technique may be successfully used as a secondary access in patients with maturation failure due to RA stenosis to accelerate fistula maturation.