Computational model-based hemodynamic comparisons of traditional and modified idealized models of autologous radiocephalic fistula.

Autologous arteriovenous fistula (AVF) is a commonly used vascular access (VA) for hemodialysis, and hemodynamic changes are one of the main factors for its failure. To explore the effect of geometry on the hemodynamics in the AVF, a modified model is built with a gradual and smooth turn at the anastomosis and is compared with the traditional model, which has an abrupt sharp turn at the anastomisis. Transient computational fluid dynamics (CFD) simulations were performed for the comparison and analysis of the hemodynamic fields of the two models at different stages of the pulse cycle. The results showed that the low shear stress region and high oscillatory shear stress region in the modified AVF model coincided with regions of intimal hyperplasia that have been identified by previous studies. A comparison with the blood flow velocities measured in vivo was performed, and the error between the simulation results and the medical data was reduced by 22% in the modified model, which verifies the rationality and utility of the modified model.

MSCTA imaging analysis of autologous arteriovenous fistula dysfunction in maintenance hemodialysis patients.

OBJECTIVE: To observe the multi-slice spiral CT angiography (MSCTA) imaging features of arteriovenous fistula dysfunction in patients undergoing maintenance hemodialysis and analyze the significance of the imaging examination. METHODS: Altogether 90 patients with end-stage renal disease treated by maintenance hemodialysis in General Hospital of China Resources & Wisco from June 2020 to February 2023 were divided into a normal function group (n=68) and a dysfunction group (n=22) according to the function of autogenous arteriovenous fistula. The clinical data of the two groups were recorded. The MSCTA was performed in each patient, and the manifestations of arteriovenous fistula dysfunction were analyzed. Additionally, the vascular access stenosis, vascular access lumen stenosis, arteriovenous diameter, blood flow, and hemodynamic indices were tested, and the value of MSCTA in predicting arteriovenous fistula function was analyzed by Logistic regression. RESULTS: The degree of vascular access stenosis and vascular access lumen stenosis in the normal group were less than those in the dysfunctional group (P<0.05). The arteriovenous diameter, blood flow, blood flow velocity at anastomotic vein end, dialysis adequacy (spKt/V), and von Willebrand factor (vWF) function in the normal group were larger than those in the dysfunction group, and the radial artery shear force was lower than in the dysfunction group, with statistical significance (P<0.05). Among the arteriovenous fistula dysfunction, there were 3 patients with anastomotic + outflow vein stenosis, 4 patients with outflow vein stenosis, 9 patients with inflow artery + anastomosis + outflow vein stenosis, and 6 patients with superior vena cava stenosis. Logistic regression analysis showed that slow blood flow velocity at the venous end of anastomosis and high shear force of radial artery were influencing factors of arteriovenous fistula dysfunction, and the area under ROC curve of blood flow velocity at the venous end of anastomosis plus shear force of radial artery was 0.93, with a sensitivity of 0.87 and a specificity of 0.85. CONCLUSION: MSCTA can be used to evaluate the dysfunction of autologous arteriovenous fistula in patients undergoing maintenance hemodialysis, and provide important reference information for the formulation of the next best clinical treatment plan.

New-onset atrial fibrillation following arteriovenous fistula increases adverse clinical events in dialysis patients with end-stage renal disease.

Background: End-stage renal disease (ESRD) patients have a high potential cardiovascular burden, and cardiovascular disease (CVD) is the leading cause of death in maintenance haemodialysis (MHD) patients. Arteriovenous fistula (AVF) is the preferred vascular access for MHD patients, but AVF significantly affects the haemodynamics of the cardiovascular system, leading to or exacerbating CVD, including atrial fibrillation (AF). This study aimed to evaluate the impact of AVF on cardiac function, especially of the left atrium (LA), in patients with ESRD and to further explore the relationship between AVF establishment and the occurrence of AF. Methods: We selected 1,107 ESRD patients on haemodialysis using AVF and 550 patients with tunneled-cuffed catheters (TCC) admitted between January 2016 and December 2022 for follow-up to compare the rate of AF between the two groups. A total of 153 patients in the AVF group with complete information (clinical data, echocardiographic and biochemical indices, and other data) were enrolled and retrospectively analysed for risk factors for the development of AF and were followed up for adverse clinical outcomes (including all-cause death, cardiac death, readmission due to heart failure, and stroke). Results: The incidence of new-onset AF was higher in the AVF group than the TCC group after dialysis access was established (16.30% vs. 5.08%, P < 0.001). Echocardiography showed that the LA anteroposterior diameter increased (P < 0.001) and the incidence of AF increased from 11.76% to 26.14% (P = 0.001) after AVF establishment. Multivariate logistic regression analysis showed that age and LA enlargement were independent risk factors for new-onset AF after AVF establishment (P < 0.05). Adverse clinical outcomes were more common in patients with AF than in patients without AF (P < 0.001). Multivariate Cox risk regression analysis suggested that new-onset AF (HR = 4.08, 95% CI: 2.00-8.34, P < 0.001) and left ventricular systolic dysfunction (HR = 2.42, 95% CI: 1.20-4.88, P = 0.01) after AVF establishment were independent risk factors for adverse clinical outcomes. Conclusion: LA enlargement after AVF establishment is associated with a significant increase in the incidence of AF, in addition, AF which is as an important influential factor in patients with MHD combined other systemic diseases might increase adverse clinical events. Clinical Trial Registration: (NCT06199609).

Differential expression of serum TM, PAF, and CD62P in patients with autologous arteriovenous fistula and the correlation with vascular access function.

BACKGROUND: End-stage renal disease (ESRD) is the final stage of chronic kidney disease (CKD). AIMS: We aimed to analyze the expression differences of serum thrombomodulin (TM), platelet-activating factor (PAF), and P-selectin (CD62P) in patients with autologous arteriovenous fistula (AVF) and the correlation with vascular access function. METHODS: The case data were retrospectively analyzed. Moreover, 160 patients with AVF maintenance hemodialysis were selected as the AVF group, and 150 healthy participants were selected as the healthy control group. According to the function of vascular access, patients in the AVF group were divided into Group A (n = 50, after the first establishment of AVF), Group B (n = 64, normal vascular access function after hemodialysis treatment), and Group C (n = 46, vascular access failure). Pearson analysis was conducted to explore the correlation between serum TM, PAF, CD62P content, and vascular pathological examination indicators, to evaluate the value of TM, PAF, and CD62P levels in predicting vascular access failure in patients with AVF. RESULTS AND DISCUSSION: The serum levels of TM, PAF, and CD62P were positively correlated with the expressions of CD68 and MCP-1, respectively (p < .001). Serum TM was positively correlated with the levels of PAF and CD62P (p < .001), and PAF was positively correlated with the levels of CD62P (p < .001), respectively. Serum levels of TM, PAF and CD62P were risk factors for vascular access failure in AVF patients (p < .05). The area under the curve of serum TM, PAF and CD62P levels in predicting vascular access failure in AVF patients was 0.879. CONCLUSION: The serum levels of TM, PAF, and CD62P in AVF patients were correlated with the vascular access function of AVF patients, which was very important for maintaining the stability of vascular access function, and had certain value in predicting vascular access failure/disorder in AVF patients, and could be popularized and applied.

The RADAR technique in reconstruction of failed autologous arteriovenous fistulas due to juxta-anastomotic stenosis is equivalent to that with traditional surgery in maintenance hemodialysis patients.

OBJECTIVE: Autologous arteriovenous fistula (AVF) is recommended as superior vascular access for hemodialysis but has a high rate of failure, and juxta-anastomotic stenosis (JAS) is one of the predominant causes of fistula failure. The aim of this study was to compare the primary patency in reconstruction of failed AVFs due to JAS between the radial artery deviation and reimplantation (RADAR) technique and traditional surgery (end-vein to side-artery neo-anastomosis) in maintenance hemodialysis (MHD) patients. METHODS: A total of 1215 MHD patients with failed AVF were enrolled in this retrospective cohort study, and 614 patients with failed AVF received surgical intervention. Among these surgical interventions, 417 patients experienced AVF failure due to JAS. Finally, 25 patients who received the RADAR technique were enrolled. Controls of 50 patients received traditional surgery were randomly selected matched by age and sex. Clinical data such as age, sex, comorbidities, and blood biochemical indices were collected. Kaplan-Meier survival curves and Cox proportional hazards analyses were used to explore the difference between the RADAR group and the traditional group in reconstruction of failed AVFs. RESULTS: The RADAR group and the traditional group shared common baseline characteristics. The primary patencies of the reconstructed AVFs were 88.8%, 79.0%, 72.2%, 57.4%, and 38.3% at 12, 24, 36, 48, and 60 months among the 75 patients, respectively. Kaplan-Meier survival curve analysis demonstrated similar primary patencies in the two groups (log-rank test, p = 0.73). Compared with the traditional group, the RADAR group had no difference in predicting AVF failure after adjusting for potential confounders, with an HR of 0.92 (95% CI, 0.18-4.63). CONCLUSIONS: The primary patency of the RADAR technique and the traditional surgery in the reconstruction of failed AVFs due to JAS is almost equal in 5 years.

The Potential Roles of CHI3L1 in Failed Autologous Arteriovenous Fistula in End-Stage Renal Disease.

Autologous arteriovenous fistula (AVF) is commonly placed for hemodialysis treatment. Recent studies show that increased baseline serum level of Chitinase-3-like protein 1 (CHI3L1) is independently associated with a higher risk of the early failure of forearm AVFs. However, the changes and mechanisms of CHI3LI in local vascular tissues of failed AVF have not be revealed. This study aims to conduct the expression and mechanism of CHI3L1 in vascular tissues from patients. Immunoreactivity of CHI3L1, matrix metalloproteinase 2 (MMP-2) and vascular endothelial growth factor-A (VEGF-A) were detected in vascular tissues collected from nine patients with AVF surgery. Due to the significant stenosis clinically, six of the nine patients received arteriovenous fistula reconstruction. The expression differences of CHI3L1 between the initial vascular tissues and failed AVF are significant (P < 0.05). Failed AVF due to stenosis shows intraluminal thrombus, collagen fiber rupture, fibrous connective tissue hyperplasia, tube wall thickening, neovascularization, scattered inflammatory cell infiltration in the tunica media as well as high CHI3L1 expression level, and the expression of MMP-2 (r = 0.9022, P = 0.0139) and VEGF-A (r = 0.8355, P = 0.0393) was positively correlated with CHI3L1. CHI3L1 expression in vascular tissues possibly plays an important role in AVF failure. MMP-2 and VEGF-A may participate in venous stenosis with CHI3L1.

The risk factors of autogenous arteriovenous fistula dysfunction in maintenance hemodialysis patients and the curative effect of personalized nursing.

OBJECTIVE: To explore the effect of individualized nursing intervention on autologous arteriovenous fistula (AVF) dysfunction and the risk factors leading to failures in maintenance hemodialysis (MHD) patients. METHODS: A total of 196 patients undergoing MHD in our hospital from March 2017 to May 2019 were recruited as the study cohort and divided into two groups according to the nursing method each patient underwent. The patients who underwent individualized nursing intervention were placed in the research group (RG, n = 107), and the patients who underwent routine nursing intervention were placed in the control group (CG, n = 89). The proportion of patients with primary dysfunction in the use of AVF was recorded, and the patients' psychological states, treatment compliance, and self-nursing abilities in the two groups before and after the nursing intervention were observed. The complications, the life treatment scores, and the patients' nursing satisfaction were recorded after the nursing intervention. A logistic regression analysis was performed for the patients with initial AVF dysfunction. RESULTS: Compared with the CG, the patients in the RG after the nursing intervention had statistically lower AVF dysfunction rates, notably lower SAS and SDS scores, remarkably higher total compliance rates and ESCA scores, and a dramatically lower total incidence of complications. AVF dysfunction occurred in 26 of 196 patients (13.4%) during the follow-up, with an increased risk of AVF loss in patients over 60 years old, lower blood pressure, higher hemoglobin concentrations, lower treatment compliance, self-care inability, and routine nursing interventions. After the nursing, the WHOQOL-BREF and nursing satisfaction scores in the RG were noticeably higher than they were in the CG. CONCLUSION: Autologous AVF dysfunction is the result of multiple risk factors, and personalized nursing can reduce the incidence of complications, improve patients' treatment compliance and self-care abilities, and ameliorate their quality of life.

Factors associated with dysfunction of autogenous arteriovenous fistula in patients with maintenance hemodialysis: a retrospective study.

BACKGROUND: Patients in maintenance hemodialysis (MHD) need a patent vascular access for optimal treatment. Autologous arteriovenous fistula (AVF) is the optimal vascular access for patients with MHD. However, AVF dysfunction may limit its use. The aim of this article is to explore the factors associated with primary dysfunction of AVF in patients with MHD. METHODS: This is a retrospective study. A total of 121 patients who underwent anastomosis for AVF in our hospital from January 1st, 2016 through December 31st, 2018 were screened for eligibility. Of these patients, 44 were excluded according to the exclusion criteria. The remaining patients were divided into two groups based on the function of vascular access. The complete blood count and other blood biochemical parameters were compared between two groups. The risk factors associated with AVF dysfunction were analyzed by multivariate Cox proportional hazard regression model for patients with end-stage renal disease (ESRD). RESULTS: There were significant differences in serum phosphorus (P), total cholesterol (TC), low density lipoprotein (LDL) and gender between patency and dysfunction groups of AVFs (P<0.05). Further multivariate COX proportional risk regression showed that hypercholesterolemia and hyperphosphatemia were independent risk factors for AVF dysfunction. CONCLUSIONS: Hypercholesterolemia and hyperphosphatemia are independent risk factors for primary AVF dysfunction in patients with MHD.

Chitinase-3-like protein 1 is an independent risk factor for the early failure of forearm autologous arteriovenous fistulas in uremic patients.

Chitinase-3-like protein 1 (CHI3L1) has been introduced as a marker of inflammation in different diseases, which can promote cell proliferation and differentiation. It has also been demonstrated that elevated serum CHI3L1 concentration can independently predict all-cause mortality in uremic patients. However, the impact of CHI3L1 on the early failure of autologous arteriovenous fistulas (AVFs) in uremic patients remains unknown. We conducted a prospective observational cohort study of 109 uremic patients (mean age 53.2 ± 14.7 years, 67.9% males), who received forearm AVF surgery, and were consecutively enrolled with a median follow-up time of 15 months. The early failure was defined as a fistula that never developed adequately for dialysis or that failed within the first 3 months of use. Serum CHI3L1 concentration was determined by the ELISA method. Among 109 uremic patients, 24 patients had AVF failure. The optimal cutoff value based on the receiver operating characteristics analysis of CHI3L1 was 122.6 ng/mL, with the area under the curve of 0.73 (P = 0.001). The Kaplan-Meier survival analysis demonstrated that patients with CHI3L1 < 122.6 ng/mL had better AVF patency than patients with CHI3L1 ≥ 122.6 ng/mL (Log-rank test, P = 0.001). Multivariable Cox proportional hazards regression analysis showed that baseline CHI3L1 level (≥ 122.6 ng/mL vs. < 122.6 ng/mL) was significantly associated with AVF failure after adjustment for confounders (adjusted hazard ratio [HR], 3.67; 95% CI, 1.44-9.36). The study demonstrated that Increased baseline serum level of CHI3L1 is independently associated with higher risk of the early failure of forearm AVFs.

Serum levels of the endothelial glycocalyx constituents and the early failure of forearm autologous arteriovenous fistulas in end-stage renal disease patients: a prospective cohort study.

BACKGROUND: The relationship between the endothelial glycocalyx constituents and the early failure of autologous arteriovenous fistulas (AVFs) in ESRD patients is still unknown. METHODS: In this prospective cohort study, 181 ESRD patients (the mean age was 53.3 ± 11.8 years, 66.3% of them were males) received forearm AVFs surgery were consecutively enrolled with a median follow-up time of 10 months. The early AVF failure was defined as a fistula that never developed adequately for dialysis use or that failed within the first 3 months of use. The serum levels of glycocalyx constituents including glypicans-1 (GPC-1), syndecans-1 (SDC-1), and hyaluronan (HA), and the indicator of endothelial activation reflected by E-selectin (ES) were determined by ELISAs. RESULTS: The primary patencies of AVFs were 98.3%, 96.7%, 91.7%, and 89.5% at 3, 6, 12, and 18 months, respectively. The ROC curve was plotted and demonstrated that HA, not GPC-1, SDC-1 or ES, can diagnose the AVF failure, with the cut-off value of 6.37 ng/ml, the sensitivity of 87.5%, the specificity of 46.9%, and the Youden index of 0.34, respectively. The Kaplan-Meier survival analysis demonstrated that patients with HA < 6.37 ng/mL had better patency of AVFs than patients with HA ≥ 6.37 ng/mL (log-rank test, p = 0.008). In the Cox proportional hazards analysis, after adjusting for confounders, HA (≥ 6.37 ng/mL vs. < 6.37 ng/mL) was associated with the early AVFs failure, with the OR of 5.88 (1.21-28.60). CONCLUSIONS: This study demonstrated that HA can predict the early failure of forearm AVFs, when its serum level is more than 6.37 ng/mL.

Plasma D-Dimer Level and the Failure of Forearm Autologous Arteriovenous Fistula in Patients With End-Stage Renal Disease.

Failed autologous arteriovenous fistula (AVF) is a major issue in the creation of functional hemodialysis vascular access. To date, the relationship between D-dimer and AVF failure is still uncertain. Hence, we conducted a retrospective cohort study to explore the patency rate of forearm AVFs and to clarify whether plasma D-dimer level can predict the failure of AVFs. In this study, 290 ESRD patients (the mean age 54.1 ± 14.6 years, 63.8% of them were males) receiving forearm AVFs surgery were consecutively enrolled with a median follow-up time of 34 months. Primary patency rates and risk factors associated with AVFs failure were explored by the Kaplan-Meier method or Cox proportional hazards model. Patients were divided into two groups based on the median level of D-dimer (group 1 <1.1 mg/L and group 2 ≥1.1 mg/L). The Kaplan-Meier survival analysis demonstrated that the patency of AVF in group 1 was similar in group 2, which were 92.4% versus 88.9%, 84.8% versus 84.0%, 80.0% versus 79.2%, 76.7% versus 78.5%, and 76.7% versus 78.5% at 12, 24, 36, 48, and 60 months (Log-rank test, P = 0.8), respectively. In the crude analysis, D-dimer (per 1 mg/L increase) was independently associated with AVFs failure, with OR of 1.08 (95% CI, 1.02-1.15). However, after adjusting for potential confounders, the D-dimer (per 1 mg/L increase) was not associated with the AVFs failure (OR = 1.06, 95% CI = 0.99-1.13). This study did not find that the plasma D-dimer level can predict the failure of forearm AVFs.

Clinical outcomes following the surgery of new autologous arteriovenous fistulas proximal to the failed ones in end-stage renal disease patients: a retrospective cohort study.

Background: Most prior studies have explored surgery for the treatment of failed autologous arteriovenous fistulas (AVFs) with limited follow-up times and a lack of end point mortality. Accordingly, we conducted a retrospective cohort study to evaluate the clinical outcomes of the surgery of new AVF proximal to the failed forearm AVF.Methods: In this study, 538 end-stage renal disease patients (group A, 418 with primary AVF; and group B, 120 with failed AVF) were consecutively enrolled between January 2013 and June 2016, with a median follow-up time of 41 months. Primary and secondary patency, all-cause mortality, and risk factors associated with AVF failure were explored by the Kaplan-Meier method or Cox proportional hazards model.Results: In group A (n = 418), the primary and secondary patencies of AVF were 85.6% vs. 96.8%, 79.7% vs. 95.0%, 75.1% vs.93.9%, 73.2% vs. 93.6% and 73.2% vs. 93.6% at 12, 24, 36, 48 and 60 months, respectively. The primary patencies of AVF in group B were 95.0%, 91.7%, 89.2%, 88.3% and 88.3% at 12, 24, 36, 48 and 60 months, respectively. After adjusting for potential confounders, age, angiotensin-converting inhibitors or angiotensin-receptor blockers (anti-RAAS) drugs and D-dimer were independent predictors of AVF failure. However, there were no differences between functional and failed AVF regarding all-cause mortality.Conclusions: The study revealed that the primary and secondary patiencies of the surgery of new AVF proximal to the failed ones were ideal operations to restore failed forearm AVF.

Factores pronósticos de las complicaciones de las fístulas arteriovenosas autólogas para hemodiálisis / Prediction factors of the autologous arteriovenous fistula complications for hemodialysis

Se realizó un estudio retrospectivo, transversal y descriptivo, para determinar los factores pronósticos sobre la aparición de complicaciones en 300 pacientes con una fístula arteriovenosa creada, atendidos en el Servicio de Angiología y Cirugía Vascular del Hospital Provincial Docente "Saturnino Lora" de Santiago de Cuba durante el trienio 2012- 2015. Entre los resultados principales predominaron el sexo femenino (52,7%), el grupo etario de 51-60 años (55,6%), la hipertensión arterial y la diabetes mellitus como factores de riesgo más comunes, así como la complicación de la FAV a nivel de la muñeca, principalmente en las féminas (34,2 %). Se concluyó que las complicaciones de la fístula arteriovenosa dependen de la presencia o no de factores de riesgo, que pueden ser un marcador negativo que afecta la calidad de vida del paciente y por sí mismos determinan el tiempo de supervivencia.

A retrospective, cross-sectional and descriptive study was carried out, to determine the prediction factors about the emergence of complications in 300 patients with a created arteriovenous fistula, assisted in the Angiology and Vascular Surgery Service of "Saturnino Lora" Teaching Provincial Hospital in Santiago de Cuba during the triennium 2012 - 2015. Among the main results the female sex (52.7%), the 51-60 age group (55.6%), hypertension and diabetes mellitus prevailed as the most common risk factors, as well as the AVF complication at wrist level, mainly in females (34.2%). It was concluded that the arteriovenous fistula complications depend on the presence or not of risk factors that can be a negative marker that affects the patient's life quality and per se determine the survival time.