Primary Unassisted Patency Rates Research Articles

Modified no-touch technique for radio-cephalic arteriovenous fistula increases primary patency and decreases juxta-anastomotic stenosis.

Low primary patency rate is a major problem of radio-cephalic arteriovenous fistula (RC-AVF) creation. Radial artery deviation and reimplantation (RADAR) is associated with low juxta-anastomotic stenosis rate. However, inflow artery stenosis is prominent with RADAR. To further reduce injury to veins and arteries during operation, a modified no-touch technique (MNTT) was used to create RC-AVF. We retrospectively reviewed our prospectively maintained database of patients with end-stage renal disease (ESRD)s undergoing RC-AVF creation for hemodialysis using either the MNTT between January 2021 and January 2022 (MNTT group) or conventional surgical procedure ( end-to-side vein-to-artery anastomosis) between October 2016 and October 2017 (Control group). Patients who chose to undergo RC-AVF surgery underwent standardized preoperative mapping and postoperative fistula evaluations using duplex ultrasound. Additionally, 4D flow MRI data were used to visualize and quantify the hemodynamics of one RC-AVF by MNTT. Outcomes included primary patency, juxta-anastomotic stenosis, and maturation rates. Forty patients underwent RC-AVFs by MNTT, compared to 60 patients in the control group. The MNTT group had a higher primary unassisted patency rate than the control group (p = 0.038). Juxta-anastomotic stenosis (all on the cephalic vein) occurred in 4 (10%) patients who underwent MNTT. RC-AVF maturation rates after 3 months were not different between both groups (maturation rate: 90% and 81.7% in the MNTT and control groups, respectively, p = 0.253). COX regression showed that both conventional AVF surgery (p = 0.031) and smaller cephalic vein diameter (p = 0.034) were associated with higher odds of RC-AVF failure. The AVF flow within the proximal vein remained helical during cardiac cycle. The distribution of wall shear stress (WSS) and oscillatory shear index (OSI) differed from that of conventional surgical AVF. RC-AVF by MNTT increases primary patency rate and decreases juxta-anastomotic stenosis rate. The improvement in hemodynamics may be one of the important reasons for the better patency rate of in the RC-AVF by MNTT group.

Preoperative Cardiac Index as a Predictor of Maturation and Primary Patency of Radiocephalic Arteriovenous Fistula in Hemodialysis

Background: Radiocephalic arteriovenous fistula (RCAVF) is the best access modality to be considered initially when planning arteriovenous fistula (AVF) for maintenance hemodialysis. Considering the higher incidence of RCAVF failed maturation (M), it is important to perform proper preoperative evaluation and identification of high-risk patients. There has been no study on the influence of preoperative cardiac function on the M and patency of AVFs. The purpose of this investigation is to determine whether preoperative cardiac index (CI) is a predictor of M and primary patency of RCAVF. Method: A total of 365 end-stage renal disease patients undergoing RCAVF surgery were consecutively enrolled with a median follow-up time of 20 months in this prospective cohort study. Demographics, vascular diameters measured by duplex ultrasound examination, and CI measured by echocardiography, were analyzed for effect on RCAVF primary functional M and primary patency. Result: Patients in the group achieving primary RCAVF functional M had a significantly larger mean CI than the group with early RCAVF failure (2.93 ± 0.77 vs. 3.57 ± 0.76 L/min/m², p < 0.001). The receiver operating characteristic curve was plotted and demonstrated that preoperative vein diameter and CI can predict failure of RCAVF M. The AUC of CI was higher (0.745 vs. 0.666). Multivariate regression analysis, adjusted for age, sex, diabetes, preoperative dialysis status and vessel diameters, showed that decreased CI remained associated with increased risk of failure of M (FM) and worse primary unassisted patency. The Kaplan-Meier survival analysis suggested that patients with CI <3 L/min/m² had a worse primary unassisted patency rate at all time points compared with patients with CI ≥3 L/min/m². Conclusion: This study demonstrated that preoperative CI was associated with RCAVF M and long-term patency. A decreased CI may be a possible predictor of an increased risk of FM and a shorter primary patency time.

Short interposition with a small-diameter prosthetic graft for flow reduction of a high-flow arteriovenous fistula

ObjectiveThe objective of this study was to evaluate the outcome of a short interposition using a small-diameter prosthetic graft as a flow-limiting procedure to manage symptomatic high-flow arteriovenous fistula (AVF). MethodsA retrospective review of medical records on a case series was conducted. From June 2004 to April 2017, there were 25 patients with clinical symptoms of high output cardiac failure and progressive dilation of aneurysmal fistula vein due to high-flow AVF (≥1.5 L/min) who underwent short interposition with a 5-mm prosthetic graft at Saitama Medical Center. The primary outcome was the relief of clinical symptoms; other outcome measures included technical success, surgical complications, patency of vascular access, and postoperative changes in local and systemic hemodynamics as assessed by Doppler ultrasound. ResultsTwenty-five patients underwent short interposition for cardiac indications (n = 16) and aneurysmal dilation (n = 9). The technical success rate was 100%. The clinical symptoms were relieved in 24 patients (96.0%). Mean reduction in access blood flow was 52.4%. Cumulative primary unassisted patency rates (± standard error) at 1 year, 2 years, and 3 years were 76.2% ± 9.3%, 70.4% ± 10.3%, and 58.1% ± 11.6%, respectively. Secondary patency rates (± standard error) at 1 year, 2 years, and 3 years were 81.8% ± 8.2%, 71.5% ± 9.9%, and 71.5% ± 9.9%, respectively. Complications included access occlusion due to late thrombosis (n = 5 [21.7%]) and graft infection (n = 1 [4.3%]) in the median follow-up period of 3.9 years. ConclusionsShort interposition with a prosthetic graft is a simple, effective, and durable treatment option for end-stage renal disease patients with cardiac symptoms and progressive dilation of the fistula vein due to high-flow AVF, offering clinical symptom resolution while preserving the autologous behavior of the initial access.

Longevity and infection free survival of permicath

Abstract Background A hemodialysis catheter is a small biocompatible tube made of soft flexible material. It is inserted into a patient’s target vein to provide vascular access for hemodialysis. As important as catheter placing and handling guide-lines to prevent infection reporting standards are equally important, as they are the tools to enable us to evaluate our work attitudes, how much are we sticking to the guide-lines, how are we managing our resources, and are we aware of the resources we have or not. Aim of the Work to figure the outcome and infection rate related to tunneled-cuffed catheters in patients with ESRD needing dialysis who were submitted to tunneled cuffed catheter placement during the period from May 2017 to April 2018. Patients and Methods This retrospective descriptive study was conducted in 35 TTCs patients in the Vascular Surgery department ASU Hospital. Target population included patients of ESRD who were submitted for tunneled cuffed dialysis catheter placement in the Vascular Surgery department ASU Hospital in the period from May 2017 to April 2018. Results A total of 35 TCCs were inserted in end-stage renal disease patients for hemodialysis. Total number of catheter days was 6343 days. The primary unassisted patency rates at 6 months and 1 year were 51.4% and 11.4% respectively. Of the 35 cases 19 (54.28% of the total population) reported infection episode. 5 (26.3% of the infected population) TCCs were removed due to a severe episode of BSI, of the removed TCCs 2 (10.5% of the infected population) were died. The TCC bacteraemia rate was 2.186 per 1000 catheter days. The total number of the removed TCCs was 14 (40% of the total population). The reasons for removal were non-patency, infection, and completion of therapy with percentage of 22, 8%, 14.3%, and 2, 9% respectively. Conclusion Tunnelled cuffed haemodialysis catheters are vital line of treatment in patients requiring long term haemodialysis especially elderly population with weak vasculature or consumed peripheral accesses in which it is considered an access of choice.

Relevance of a skilled vascular surgeon and optimized facility practices in the long-term patency of arteriovenous fistulas: a prospective study.

Introduction:Arteriovenous fistulas (AVF) are the best hemodialysis vascular accesses, but their failure rate remains high. Few studies have addressed the role of the vascular surgeon's skills and the facility's practices. We aimed to study these factors, with the hypothesis that the surgeon's skills and facility practices would have an important role in primary failure and patency rates at 12 months, respectively.Methods:This was a single-center, prospective cohort study carried out from March 2005 to March 2017. Only incident patients were included. A single surgeon made all AVFs, either in the forearm (lower) or the elbow (upper). Vascular access definitions were in accordance with the North American Vascular Access Consortium.Results:We studied 113 AVFs (65% lower) from 106 patients (39% diabetics, 58% started with catheter). Time to first connection was 21.5 days (IR: 14 - 31). Only 14 AVFs (12.4%) underwent primary failure and 18 failed during the first year. Functional primary patency rate was 80.9% (SE 4.1) whereas primary unassisted patency rate, which included PF, was 70.6% (4.4). Logistic regression showed that diabetes (OR = 3.3, 95%CI 1.38 - 7.88, p = .007) and forearm location (OR = 3.03, 95CI% 1.05 - 8.76, p = 0.04) were predictors of AVF failure. Patency of lower and upper AVFs was similar in non-diabetics, while patency in diabetics with lower AVFs was under 50%. (p = 0.003).Conclusions:Results suggest that a long-lasting, suitable AVF is feasible in almost all patients. The surgeon's skills and facility practices can have an important role in the long term outcome of AVF.

Novel use of the ClariVein® catheter for pharmacomechanical thrombolysis of thrombosed hemodialysis grafts: a case series.

The aim of this prospectively collected case series is to demonstrate a novel technique of using the ClariVein® catheter for pharmacomechanical thrombolysis of thrombosed hemodialysis grafts. The analysis comprised 11 procedures in 9 patients from 1 July to 31 December 2016 in which the ClariVein catheter was used in combination with urokinase. Demographic data, procedural data, technical and clinical success rates, and complications were evaluated. The primary and secondary patency rates at 1 and 3 months were also analyzed. In the 11 procedures performed, the technical and clinical success was 100%. The mean procedural time was 66.8 minutes (range 50-90 minutes), and the mean amount of urokinase administered was 87,000 units. The primary unassisted patency rates at 1 and 3 months were 81.8% and 63.6%, respectively. The secondary patency rates at 1 and 3 months were 90.9% and 81.8%, respectively. Perforation occurred after balloon angioplasty in 1 (9.1%) of the 11 procedures, for which covered stenting was performed. No major complications occurred. The combination use of the ClariVein catheter with urokinase for pharmacomechanical thrombolysis in thrombosed hemodialysis grafts is a feasible and safe method that can be performed in a relatively short duration. Our early results have shown 100% technical and clinical success. This case series serves as a platform for an upcoming prospective study to further evaluate this method.

Effect of initial stent position on patency of transjugular intrahepatic portosystemic shunt.

AIMTo evaluate the effect of initial stent position on transjugular intrahepatic portosystemic shunt (TIPS).METHODSWe studied 425 patients from January 2004 to January 2015 with refractory ascites or variceal bleeding who required TIPS placement. Patients were randomly divided into group A (stent in hepatic vein, n = 57), group B (stent extended to junction of hepatic vein and inferior vena cava, n = 136), group C (stent in left branch of portal vein, n = 83) and group D (stent in main portal vein, n = 149). Primary unassisted patency was compared using Kaplan-Meier analysis, and incidence of recurrence of bleeding, ascites and hepatic encephalopathy (HE) were analyzed.RESULTSThe mean primary unassisted patency rate in group B tended to be higher than in group A at 3, 6 and 12 mo (P = 0.001, 0.000 and 0.005), and in group D it tended to be lower than in group C at 3, 6 and 12 mo (P = 0.012, 0.000 and 0.028). The median shunt primary patency time for group A was shorter than for group B (5.2 mo vs 9.1 mo, 95%CI: 4.3-5.6, P = 0.013, log-rank test), while for group C it was longer than for group D (8.3 mo vs 6.9 mo, 95%CI: 6.3-7.6, P = 0.025, log-rank test). Recurrence of bleeding and ascites in group A was higher than in group B at 3 mo (P = 0.014 and 0.020), 6 mo (P = 0.014 and 0.019) and 12 mo (P = 0.024 and 0.034. Recurrence in group D was higher than in group C at 3 mo (P = 0.035 and 0.035), 6 mo (P = 0.038 and 0.022) and 12 mo (P = 0.017 and 0.009). The incidence of HE was not significantly different among any of the groups (P = 0.965).CONCLUSIONThe initial stent position can markedly affect stent patency, which potentially influences the risk of recurrent symptoms associated with shunt stenosis or occlusion.

Reply to “Viatorr TIPS Endoprosthesis Versus Generic Expanded Polytetrafluoroethylene–Covered Stent-Grafts”

AJR 2015; 205:W1 0361–803X/14/2054–W1 © American Roentgen Ray Society Reply to “Viatorr TIPS Endoprosthesis Versus Generic Expanded ­Polytetrafluoroethylene–Covered Stent-Grafts” We agree with Dr. Tsauo and Dr. Li [1] that there is a lack of comparative data on the different types of expanded polytetrafluoroethylene (ePTFE)–covered stent-grafts available for use in transjugular intrahepatic portosystemic shunt (TIPS) procedures. As they discussed, the Fluency Plus (Bard Peripheral Vascular) ePTFE-covered stent-graft has slightly flared and uncovered 37-mm ends on both sides of the stent-graft. In the United States, the stent-graft is indicated for use in stent-restenotic lesions in arteriovenous fistulas and grafts. In contrast, the Viatorr TIPS Endoprosthesis (W. L. Gore & Associates) has a direct indication for TIPS and contains a 2-cm uncovered bare metal portion that can be deployed along the portal aspect of the shunt. Both are self-expanding stent-grafts. The 1-year primary unassisted patency rate has been reported to be 81% versus 89% for the Fluency Plus and Viatorr TIPS Endoprosthesis stent-grafts, respectively. No statistically significant differences were found in the major encephalopathy or hemodynamic success rates of TIPS. Saad et al. [2] used a technique in which a bare metal stent was used along the portal end, in combination with a Fluency Plus stent-graft, instead of relying on the short bare metal flared end of the stent-graft. In comparison, the Viatorr TIPS Endoprosthesis is often deployed as a single stent-graft. Thus, future cost-effectiveness studies should address comparisons of technique, including the number of stents and stent-grafts used, and should not simply compare the two stent-grafts alone. Fluency Plus stent-grafts are likely effective for use in TIPS [3] and may have increased efficacy when compared with other polymer stent-grafts [4]. Fluency Plus stentgrafts may represent an alternative in areas where Viatorr TIPS stent-grafts are unavailable; however, the limitations of Fluency Plus, as used in the United States, include absence of an indication for TIPS, lack of comparative data, and uncertain cost-effectiveness. Zachary L. Bercu Icahn School of Medicine at Mount Sinai, New York, NY Present address: Emory University School of Medicine, Atlanta, GA Aaron M. Fischman Robert A. Lookstein Icahn School of Medicine at Mount Sinai, New York, NY DOI:10.2214/AJR.15.14822 WEB—This is a web exclusive article.

Prospective multicenter study with a 1-year analysis of a new vascular graft used for early cannulation in patients undergoing hemodialysis

More than 85% of patients with end-stage renal disease start dialysis through a tunneled dialysis catheter (TDC) for long periods while their arteriovenous fistula or vascular access graft (arteriovenous graft [AVG]) matures. Because TDCs are associated with a high risk of complications, including death and infection, use of an AVG that can be cannulated safely immediately after implantation may reduce morbidity in these patients by allowing earlier TDC removal. We report a prospective multicenter study of a new early-cannulation AVG (Gore ACUSEAL Vascular Graft; W. L. Gore & Associates, Flagstaff, Ariz). Patients requiring creation of a prosthetic vascular access for hemodialysis were enrolled between July 2010 and February 2012 and observed for 12 months. Data were collected on the patients' baseline characteristics; location, position, loss of patency, and revisions of prior AVGs; dialysis sessions using the AVG; and major adverse events related to graft implantation or cannulation. Cumulative and primary unassisted graft patency rates were calculated. A subgroup analysis compared outcomes in patients in whom the AVG was first cannulated within 72 hours after implantation with outcomes in patients in whom the initial cannulation was performed >21 days postoperatively. The population of this study was formed by 138 patients who received an ACUSEAL graft. During follow-up, 17 patients died and the AVG was abandoned in 27. The median value for follow-up was 360 days for all patients (variance 15,387). The overall mean time to initial cannulation was 15 days, with 54 grafts (40%) first cannulated within 72 hours after graft implantation and 33 grafts first cannulated >21 days afterward. The reason for late cannulation in some patients was dependent on the implanting surgeon's decision and the surgeon's personal experience with early cannulating grafts. The 1-year overall cumulative patency rate was 79% (95% confidence interval, 71%-85%); the primary unassisted patency rate was 35% (95% confidence interval, 27%-44%). Adverse events included 6 hematomas (two of which were related to cannulation and occurred 107 and 169 days, respectively, after AVG implantation), 15 graft infections, and 15 cases of steal syndrome requiring intervention. Patients in the early- and later-cannulation groups had similar characteristics and no significant differences in rates of cumulative or primary unassisted patency or adverse events. This study demonstrated that the new, early-cannulation AVG graft can be cannulated soon after implantation without a significant difference in patency and complication rates compared with rates associated with standard cannulation of expanded polytetrafluoroethylene grafts in the literature. This new AVG may allow early removal or avoidance of TDC use in patients undergoing hemodialysis, potentially reducing or eliminating the number of days of catheter-dependent dialysis, but further studies will be needed to demonstrate this potential.

Stent-grafts for Transjugular Intrahepatic Portosystemic Shunt Creation: Specialized TIPS Stent-graft versus Generic Stent-graft/Bare Stent Combination

To compare functional and anatomic outcomes of transjugular intrahepatic portosystemic shunts (TIPSs) created with the specialized Viatorr stent versus a Wallstent/Fluency stent combination. Retrospective review of patients who underwent TIPS creation with stent-grafts was conducted over a 54-month period ending in June 2008. Patients were divided into three groups: Viatorr only, Fluency only, and combined Viatorr/Fluency, the latter of which was included in the overall evaluation but excluded from the comparative analysis between the Viatorr and Fluency groups. Patient demographics, Child-Pugh scores, and portosystemic gradient (PSG) reduction were compared. Patencies were calculated using the Kaplan-Meier method and compared. A total of 126 TIPSs created with stent-grafts were found: 28 with Fluency stents, 93 with Viatorr devices, and five combined. No significance in demographic factors or PSGs was found among groups (P > .05). Major encephalopathy rates were 3.6% and 4.3% in the Fluency and Viatorr groups, respectively (P = 1.000). Hemodynamic success rates were 93% and 98% in the Fluency and Viatorr groups, respectively (P = .099). The primary unassisted patency rates at 6, 9, and 12 months were 87%, 81%, and 81%, respectively, in the Fluency group and 95%, 93%, and 89%, respectively, in the Viatorr group (P = .03). Portal and hepatic end stenoses were the causes of TIPS narrowing in the Fluency and Viatorr groups, respectively. The Wallstent/Fluency stent combination is associated with a 1-year patency rate greater than 80%, with no significant difference versus the Viatorr stent regarding technical and hemodynamic success and encephalopathy rate. However, the Viatorr stent is associated with improved patency (89%) versus this bare stent/stent-graft combination.

Dacron-covered Stent-Grafts in Transjugular Intrahepatic Portosystemic Shunts: Initial Experience

To retrospectively review the authors' experience with use of a Dacron-covered stent-graft in transjugular intrahepatic postosystemic shunts (TIPS). The need for internal review board approval was waived. Informed consent was obtained from all patients. The study was compliant with the Health Insurance Portability and Accountability Act. A retrospective analysis was performed of 16 patients who received a Dacron-covered stent-graft during revision or de novo creation of TIPS. There were 13 men and three women aged 44-80 years (mean age, 61 years). Primary unassisted and assisted patency rates and secondary patency rates were estimated. The primary unassisted patency of patients who underwent de novo placement of stent-grafts (n = 10) was compared with that of patients with stent-grafts placed during shunt revision (n = 6); in all patients, stent-grafts were placed within stents. Primary unassisted patency was also compared between patients in whom the covered stent was confined to the parenchymal tract (n = 7) and those in whom the stent extended 1 cm or more into the portal vein (n = 9). Patency was estimated with the Kaplan-Meier method, and group comparisons were performed with the log-rank test. Primary unassisted patency rates following stent-graft placement at 4, 12, and 24 months (+/- standard error) were 64% +/- 14, 54% +/- 15, and 40% +/- 16, respectively. The rates for primary assisted patency were 78% +/- 12, 67% +/- 14, and 67% +/- 14 and those for secondary patency were 91% +/- 9, 81% +/- 12, and 54% +/- 23. At 12 months, primary unassisted patency with de novo stent-graft placement was 90% +/- 9, whereas that with stent-grafts placed during TIPS revision was 17% +/- 15 (P = .005). At 12 months, the primary unassisted patency in patients with stent-grafts confined to the parenchymal tract was 75% +/- 22, and that of patients with stent-grafts extending at least 1 cm into the portal vein was 40% +/- 17 (P = .21). In this small series, satisfactory long-term patency was observed among patients in whom Dacron-covered stent-grafts were placed during revision or de novo creation of TIPS. More favorable outcomes were observed when the stent-graft was placed during de novo TIPS creation and when the device was confined to the parenchymal tract.

The Effect of Initial Shunt Outflow Position on Patency of Transjugular Intrahepatic Portosystemic Shunts

It has been suggested that initial stent position in transjugular intrahepatic portosystemic shunts (TIPS) with relation to hepatic venous outflow is an important determinant of shunt patency. It was hypothesized that TIPS with the stent-implanted segments terminating in the hepatic vein (HV) have shorter primary unassisted shunt patency durations than TIPS with the stent-implanted segments extending to the hepatocaval junction. A consecutive group of 107 patients who underwent TIPS creation for variceal bleeding were retrospectively identified, and the angiographic images during initial TIPS creation were reviewed independently by two observers who were blinded to outcome. Primary unassisted patency was estimated in group A (TIPS terminating in the HV; n = 47) and group B (TIPS terminating at the hepatocaval junction; n = 60) with the Kaplan-Meier method, and the two groups were compared with the log-rank test. Patients who had less than 30 days of follow-up were excluded from the analysis. Among all 107 patients, primary unassisted patency rates at 3, 6, and 12 months were 91% +/- 4%, 74% +/- 6%, and 49% +/- 6%. TIPS were classified into group A or group B with high interobserver agreement (Cohen kappa = 0.98). At 12 months, the primary unassisted patency rate among the patients in group A was 36% +/- 10%, compared with 58% +/- 8% among the patients in group B (P =.017, log-rank test). Patients in group A were twice as likely to lose patency than patients in group B (95% CI of odds ratio, 1.2-4.5). Thirty-day mortality was similar between groups (15% vs 12%; P =.13). Initial stent position within the hepatic venous outflow is predictive of shunt patency, with TIPS extending to the hepatocaval junction having a longer lifespan than shunts terminating in the HV.