Dialysis Grafts Research Articles

Sodium and Hematocrit Levels' Correlation and Clinical Impacts in Jordanian Hemodialysis Patients.

Given cofounders, this retrospective study investigates the correlation between hyponatremia status and hematocrit (Hct) changes, as well as the clinical utility of these two prognosticators in relation to overall health status. The study was retrospectively conducted on adult hemodialysis (HD) patients at the King Hussein Medical Center in Amman, Jordan, from 2015 to 2022. It looked at how sodium (Na) levels, the hematocrit-to-hemoglobin ratio (HHR), and outcomes of interest were related. The study examined acute myocardial infarction, stroke, refractory hypertension, dialysis graft thrombosis, and all-cause mortality as the composite outcomes of interest (cOI). We conducted a series of receiver operating characteristics, binary logistic regression (BLgR), and sensitivity analyses between each tested prognosticator and the cOI. We constructed and illustrated a multiple logistic regression(MLgR) model to investigate the adjusted association of each prognosticator against the tested composite outcome probability. The majority of HD patients were hemolyzed for a period of four to seven years. The constructed binary regressionmodeling for each prognosticator was [e (109.36 - 0.849 × Na)/[1 + e (109.36 - 0.849 × Na)] and [e (16.033 - 6.388 × HHR)/[1 + e (16.033 - 6.388×HHR)], with a 35.57% probability of cOI at the optimal Na of 129.51 mEq/l and a 42.8% at optimal HHR of 2.555:1. When the length of hemodialysis (LOD) was introduced into theMLgRmodeling all the investigated independent variables were significant except the HHR (p-value = 0.908). A higher LOD, lower Na, and lower HHR all support a positive cOI probability status. Regular inspection of Na and HHR and ensuring their closet to their optimal thresholds are mandatory to mitigate the risk of higher cOI probability.

Brachial Artery to Axillary Vein Dialysis Graft Creation for Salvage After Failed Upper Extremity Dialysis Access

Brachial Artery to Axillary Vein Dialysis Graft Creation for Salvage After Failed Upper Extremity Dialysis Access

Salvage of brachiocephalic aneurysmatic fistulas, using ePTFE graft with a minimally invasive approach.

In this study, we evaluated our surgical approach in requiring surgical treatment of brachiocephalic arteriovenous fistula (AVF) aneurysms for salvage of AVF. Between 2012 and 2022, 20 patients (16 men, 4 women; mean age 54.5 years) who were surgically treated for a brachiocephalic AVF aneurysm in our Cardiovascular Surgery Clinic were evaluated retrospectively. These 20 patients were operated on for aneurysm thrombosis and fistula failure in 16 patients, sudden rupture and severe bleeding in 3 patients, cosmetic reasons, and anxiety in 1 patient. These aneurysms were ligated and divided from distal and proximal cephalic veins. Then, a 6 mm dialysis graft was interposed between the well-developed cephalic vein distal and proximal to the aneurysm with small skin incisions. All patients were taken to dialysis via this dialysis graft 24 h after the procedure without any problem. All patients were discharged after dialysis. After surgery, no catheterization or any other additional procedure was required for hemodialysis. No complications, such as infection, hematoma, neurological damage, or ischemia, were observed after the surgical procedure. The mean postoperative follow-up was 12 months. In brachiocephalic AVF aneurysms requiring surgical treatment, hemodialysis can be continued with a graft placed in the same arm in this technique.

An unconventional hemodialysis vascular access through graft-vein fistula.

An abnormal fistulation occurring between a prosthetic dialysis graft and an adjacent native vein is a rare complication. However, in our patient, this abnormality ended up preserving the patency of his hemodialysis vascular access. We present a case of an unconventional hemodialysis vascular access making use of the graft-vein fistula.

Meta-analysis of total versus partial graft excision: Which is the better choice to manage arteriovenous dialysis graft infection?

Arteriovenous graft infection (AVGI) is a major cause of hemodialysis access failure. Delayed diagnosis and inappropriate treatment may lead to increased morbidity (3-35%) and mortality up to 12%. Compare the postoperative outcomes of total graft excision (TGE) and partial graft excision (PGE) in the treatment of AVGI. Systematic review and meta-analysis METHODS: The dataset was defined by searching PubMed, EMBASE, Google Scholar, and the Cochrane database for articles outlining the terms arteriovenous graft infection, infected dialysis graft, TGE and PGE published between 1995-2020. The data analysis evaluated the outcomes of TGE and PGE in the management of AVGI. The meta-analysis was performed using Review Manager Software version 5.4.1. 30-day mortality, recurrent infection, and reoperation rate. Eight studies, including 555 AVGI, and 528 patients. PGE showed a significant increase in recurrent graft infection rate (OR=0.23,95% CI=0.13-0.41, P<.00001) and re-operation rate for control of infection (OR=0.14,95% CI=0.03-0.58, P<.007). However, the 30-day mortality rate did not differ significantly between the groups (OR=0.92,95% CI=0.39-2.17, P=.85). TGE remains a safe and effective surgical method for the management of AVGI. PGE is associated with a higher risk of graft infection and need for re-operation. As a result, PGE should only be considered in carefully selected patients. Risk of bias due to the differences in patient characteristics. None.

A realistic arteriovenous dialysis graft model for hemodynamic simulations.

ObjectiveThe hemodynamic benefit of novel arteriovenous graft (AVG) designs is typically assessed using computational models that assume highly idealized graft configurations and/or simplified boundary conditions representing the peripheral vasculature. The objective of this study is to evaluate whether idealized AVG models are suitable for hemodynamic evaluation of new graft designs, or whether more realistic models are required.MethodsAn idealized and a realistic, clinical imaging based, parametrized AVG geometry were created. Furthermore, two physiological boundary condition models were developed to represent the peripheral vasculature. We assessed how graft geometry (idealized or realistic) and applied boundary condition models of the peripheral vasculature (physiological or distal zero-flow) impacted hemodynamic metrics related to AVG dysfunction.ResultsAnastomotic regions exposed to high WSS (>7, ≤40 Pa), very high WSS (>40 Pa) and highly oscillatory WSS were larger in the simulations using the realistic AVG geometry. The magnitude of velocity perturbations in the venous segment was up to 1.7 times larger in the realistic AVG geometry compared to the idealized one. When applying a (non-physiological zero-flow) boundary condition that neglected blood flow to and from the peripheral vasculature, we observed large regions exposed to highly oscillatory WSS. These regions could not be observed when using either of the newly developed distal boundary condition models.ConclusionHemodynamic metrics related to AVG dysfunction are highly dependent on the geometry and the distal boundary condition model used. Consequently, the hemodynamic benefit of a novel graft design can be misrepresented when using idealized AVG modelling setups.

Lower Limb Dialysis Grafts

The exponential rise in diabetes in India has led to a steady rise in end-stage renal disease patients requiring renal replacement therapy (RRT). Affordability and access to centers providing RRT and maintenance of functioning upper extremity vascular access for prolonged periods remain a challenge. Frequently facing no upper extremity access situations, we decided to reassess the feasibility of lower extremity vascular access. A retrospective study was carried out evaluating data from January 2009 to March 2022 including patients with a graft tunneled in the thigh (lower superficial femoral artery end to side to terminal great saphenous vein end to end). Totally 26 cases were studied with respect to age, sex, body mass index, comorbidities, difficulty in cannulation, complications, graft dysfunction, and patency rates. Follow-up was a dynamic ongoing process without a fixed endpoint. Graft dysfunction was seen in seven of 26 patients (26.92%), with a primary patency rate of 88.46% (23/26) at 1 year. Twelve subjects died during the study period, however, all had a functioning lower limb arteriovenous graft (AVG). Lack of surgical training, fear of complications, and absence of team approach in decision-making are some reasons why lower extremity permanent dialysis access is infrequently used. However, in view of increased survival on dialysis, advancing age of the dialysis population, associated comorbidities, and multiple access failures, lower limb AVGs may be considered a feasible access modality with acceptable patency rates and minimal complications.

MO767: Severe Bleeding and Infectious Complications Associated with Dialysis Access—an 11 Year Experience in Treating and Salvaging Problematic Accesses

Abstract BACKGROUND AND AIMS Penetrating ulcers and cellulitis of autogenous fistulae have become significant and common complications of haemodialysis access. Their presentation can be associated with exsanguinating haemorrhage or a severe septic picture—both endangering the access and the very life of the patient. Over a 12-year period, we have seen and treated over 70 patients requiring treatment of these types of difficult complications. METHOD There were 762 autogenous fistulae and 26 prosthetic grafts performed in the 11-year period for dialysis access. In this collection of patients, there were 76 patients who presented with severe complications of infection, bleeding ulcers, exsanguinating haemorrhage, exposed graft, or massive aneurysms. In order to apply some order to these diverse complications—they were divided into five groups. There were 12 patients and 16 procedures treated with interventional techniques of covered stent placement. There were 30 patients with 34 procedures who presented with bleeding, massive, or intermittent and were treated operatively urgently or emergently depending on their stability. A total of 23 patients were presented with ulcers on their autogenous fistula or aneurysmal dilatation of the autogenous fistula. There were 11 patients who presented with obvious and significant infection in autogenous or prosthetic grafts. There were 10 patients who presented with a prosthetic graft with persistent bleeding, an ulcer with penetration to the graft, or an exposed graft. RESULTS No patient was exsanguinated from these complications at the time of operative intervention. In reviewing the 12 patients treated with stents and interventional radiology, the range of time from the repair until death or occlusion of the graft ranged from 1–89 months and an average of 15 months. In the 30 patients who presented with bleeding—the individual patients who could be primarily repaired (20) had the best results. This entailed wide excision of the ulcer/bleeding site, repair of the vein, and a two-layer closure over the repaired vein. These patients were able to resume dialysis in 24-h through their repaired fistula. In reviewing the patients who presented with large ulcers on the fistula or aneurysm with no history of bleeding—these numbered 23 patients requiring 29 procedures. There were 13 patients who had a primary repair and excision of the ulcer and these had the best results. There were two patients with large aneurysmal Cimino fistulae who had a conversion to a mid-forearm fistula, excluding the massive aneurysm. A total of 11 patients presented with severe infection and cellulitis involving the dialysis access unresponsive to antibiotics. There were 4 patients with postoperative infections from autogenous fistula construction, and these were all treated with debridement and secondary closure. There were 10 patients with a prosthetic graft who presented with an ulcer, exposed graft, or a severe infection involving the dialysis graft. These were treated with secondary closure and irrigation. As to be expected the majority (60%) were functional for only 1–2 months. CONCLUSION The results of our study continue to affirm the use of autogenous fistula in the construction of dialysis access for those patients requiring long-term haemodialysis. In each of the five groups the best results, unequivocally, were found in those patients with an autogenous fistula repaired with autogenous tissue. The fact that these autogenous fistulae were in place for several years before requiring repair allowed their walls to become thickened and have a larger diameter. It is these two characteristics, which allowed the excision of the ulcerated/bleeding area to be excised and repaired. The size of the functioning fistula allowed the closure of the defect with no compromise of the lumen and the thickened vein walls allowed a good haemostatic closure. This study emphasizes the need for autogenous tissue for both construction and repair of haemodialysis access—whether it is for ulcers on the fistula, ulcers actively haemorrhaging, or infected fistula.

The efficacy of rotational pharmaco-mechanical thrombectomy in patients with acute iliofemoral deep vein thrombosis: is the standard treatment of deep vein thrombosis changing?

Pharmacomecanical thrombectomy with the Cleaner thrombectomy device (Argon Medical Devices, Frisco, Tex) was safe and beneficial in the treatment of acute iliofemoral deep vein thrombosis (DVT). This study retrospectively evaluated 75 patients with acute DVT involving the iliofemoral segment who underwent pharmacomechanical thrombectomy with the Cleaner thrombectomy device (Argon Medical Devices). Approximately 91% had complete thrombus resolution, and >90% could be treated in a single session. Short-term improvement occurred in post-thrombotic syndrome assessed via Villalta scores; however, the scores worsened over time. This study seems to be of another “me too” mechanical thrombectomy device that removes acute soft thrombus efficiently using a strong rotating wire that macerates the thrombus, delivers thrombolytic agents, and, basically, scrapes thrombus from the venous endothelium. The advertisements for the device state that is effective with adherent thrombus but with a reduction in the risk of endothelial damage. What data are available to support this statement, which seems to have been a common one made by the manufacturers of various thrombectomy devices during the past almost 20 years? We know that post-thrombotic syndrome can appear anywhere from 6 months to 20 years after an acute DVT. How long do the investigators plan to monitor this small group of patients? Perhaps this device is efficacious in cleaning out synthetic dialysis grafts or lower extremity bypass conduits. However, it is difficult to imagine a “powerful” wire whipping around in a delicate vein already damaged by thrombus. I am concerned additional recurrent DVTs could develop once anticoagulation therapy has been discontinued owing to the increased endothelial damage. Of course, I also have no data to support this statement.

Effectiveness of stent graft versus balloon angioplasty for failing arteriovenous dialysis graft—a single center retrospective cohort experience

Background: Evaluating stent graft (SG) and balloon angioplasty for the treatment of failing arteriovenous dialysis graft (AVG).

Computationally guided in-vitro vascular growth model reveals causal link between flow oscillations and disorganized neotissue

Disturbed shear stress is thought to be the driving factor of neointimal hyperplasia in blood vessels and grafts, for example in hemodialysis conduits. Despite the common occurrence of neointimal hyperplasia, however, the mechanistic role of shear stress is unclear. This is especially problematic in the context of in situ scaffold-guided vascular regeneration, a process strongly driven by the scaffold mechanical environment. To address this issue, we herein introduce an integrated numerical-experimental approach to reconstruct the graft–host response and interrogate the mechanoregulation in dialysis grafts. Starting from patient data, we numerically analyze the biomechanics at the vein–graft anastomosis of a hemodialysis conduit. Using this biomechanical data, we show in an in vitro vascular growth model that oscillatory shear stress, in the presence of cyclic strain, favors neotissue development by reducing the secretion of remodeling markers by vascular cells and promoting the formation of a dense and disorganized collagen network. These findings identify scaffold-based shielding of cells from oscillatory shear stress as a potential handle to inhibit neointimal hyperplasia in grafts.

Invited Commentary Open Venous Bypass in the Era of Endovascular Therapy

Central venous disease and obstruction in dialysis patients is a common problem and a cause of upper extremity access failure. Endovascular therapy, angioplasty and stenting, is the first line of therapy nowadays in treating central venous disease. However high failure rates and need for re-intervention due to external compression at the thoracic outlet led many to perform other salvage procedures like clavicle or rib resection 1. Glass C. Maevsky V. Massey T. et al. Subclavian vein to right atrial appendage bypass without sternotomy to maintain arteriovenous access in patients with complete central vein occlusion, a new approach. Ann Vasc Surg. 2009; 23: 465-468 Abstract Full Text Full Text PDF PubMed Scopus (26) Google Scholar and even more creative ideas like percutaneous bypass. 2. Chiung-Yu Chen M. Weng M.J. Percutaneous extraanatomic bypass for treatment of central venous occlusions in patients undergoing hemodialysis. AJR Am J Roentgenol. 2020; 214: 477-481 Crossref PubMed Scopus (2) Google Scholar Open central venous bypass should be considered in patients, particularly younger patients, as their life depends on a functioning upper extremity bypass. In addition, most of them have symptoms related to superior vena cava syndrome. The big questions are who should get it? What algorithm should we follow? What is the long-term patency? In the current paper, 3. Uceda P.V. Feldtman R.W. Ahn S.S. Long term results of bypass graft to the right atrium in the management superior vena cava syndrome in fialysis patients. Ann Vasc Surg. 2021; (accepted for publication) Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar the authors provide the readers with some answers to all these questions based on their experience. The authors present a mix of 5 patients (3 with fistulas, 1 with dialysis graft and 1 with dialysis catheter) treated with atrial bypass with no mortality. From the authors’ affiliation, two are vascular surgeons and one is a cardiac surgeon. Having a multidisciplinary approach, vascular and cardiac surgeons along with other interventionlists, would identify and increase the enthusiasm for this open and durable procedure and help some of the dialysis patients who need it the most.

Long Term Results of Bypass Graft to the Right Atrium in the Management of Superior Vena Cava Syndrome in Dialysis Patients

Superior vena cava (SVC) occlusion in dialysis patients is a serious complication that can cause SVC syndrome and vascular access dysfunction. While endovascular therapy has advanced to become the first line of treatment, open surgical treatment may still be needed occasionally. However, no long term outcome data has been previously reported. We performed a retrospective review of 5 dialysis patients treated with bypass graft to the right atrium from 2012 to 2014. Four patients had severe dysfunction of their upper arm dialysis access as well as superior vena cava syndrome, and one patient with a femoral tunneled dialysis catheter (TDC) had SVC occlusion. None of the patients were candidates for lower extremity access creation or peritoneal dialysis (PD). Three patients underwent a left brachiocephalic-right atrial bypass and 2 underwent a bypass from the cephalic fistula to the right atrium. All procedures were technically successful and maintained function of the arteriovenous fistulas or allowed creation of a new upper extremity dialysis graft. One-year secondary patency rate of the bypass was 100%. Longer follow up revealed that one patient died of leg sepsis and another one of a stroke within 14 months after the procedure. Another patient did well for 16 months when recurrent graft thrombosis occurred; and ultimately the graft failed after 31 months despite multiple interventions. Two patients maintained bypass graft patency during a follow up of 78 months; however, they underwent multiple endovascular interventions (23) and open vascular access procedures (4) to maintain hemodialysis function. Bypass grafts to the right atrium in dialysis patients with SVC occlusion are successful in maintaining function of already existing vascular access or new ones. Long term secondary patency can be achieved but requires strict follow up and a proactive endovascular strategy to treat lesions in the access and or the bypass graft.

Serum electrolyte/metabolite abnormalities among patients with acute myocardial infarction: comparison between patients with and without diabetes mellitus

ABSTRACT Background: Diabetes mellitus (DM) in a setting of acute myocardial infarction (AMI) is associated with significant metabolic changes and worse outcomes. Objective: To evaluate the prevalence and the prognostic significance of electrolyte/metabolite disturbances among AMI patients with vs. without DM. Methods: Patients admitted to a tertiary medical center with AMI throughout 2002–2012 were screened. Exclusion criteria were: dialysis, mechanical ventilation, and in-hospital coronary artery bypass graft (CABG) surgery. All the results of the following analyses were obtained: Glucose, Uric Acid, (UA) Calcium, Magnesium, Albumin, Potassium, and Sodium. The primary outcome was in-hospital all-cause mortality. Results: A total of 14,364 AMI patient admissions was evaluated, mean age 68.1 ± 14.4 years, 65.5% males, and 41.2% with DM. Following an adjustment to potential confounders, DM patients had increased risk for significant hyperglycemia, hyperuricemia, hypercalcemia, hypomagnesemia, hyperkalemia, and hyponatremia as well as significantly decreased risk for hypoglycemia, hypermagnesemia, and hypokalemia compared with nondiabetics. Overall, 681 (4.7%) patients died throughout the index admission. Deceased had an increased incidence of electrolyte/metabolite abnormalities versus hospital survivors. The prognostic significance of the different categories of the investigated variables is very similar among diabetics and nondiabetics, except increased and decreased uric acid levels [<4.5 (men); <4.0 (women) and ≥9.0 (men); ≥9.4 (women)] which are associated with worse outcomes among diabetics while hyperglycemia (Glucose ≥213 mg/dL) and increased Potassium levels (Potassium ≥4.4mEq/L) which comprise significantly worse prognosis among nondiabetics. Conclusions: Patients with DM admitted with AMI are at greater risk for electrolyte/metabolite abnormalities which are associated with increased risk for in-hospital mortality. The latter association is similar among patients with and without DM except for hyperglycemia and increased potassium levels (stronger among nondiabetics).

Percutaneous Thrombectomy of an Ipsilateral Arteriovenous Dialysis Graft in a Patient with Dextrocardia

Percutaneous Thrombectomy of an Ipsilateral Arteriovenous Dialysis Graft in a Patient with Dextrocardia

Retrospective Analysis of 77 Hemodialysis Patients Shows No Cases of Steal Syndrome from Graft Taper Reduction

PurposeTo review the immediate flow response and incidence of steal syndrome after taper reduction of tapered dialysis grafts. Material and MethodsThis was a retrospective review of a quality assurance database of all hemodialysis access interventions performed between 2005 and 2017. It identified 77 patients who underwent a taper reduction procedure, involving angioplasty of the arterial limb of the graft and the arterial anastomosis for graft thrombosis/poor flow. A subset of patients underwent 5-, 6-, or 7-mm balloon taper reduction angioplasty coupled with intravascular direct flow measurement (n = 15 with 16 dialysis grafts). A two-tailed Wilcoxon matched-pairs signed-rank test was used to compare pre- and post-taper reduction flows. Mean duration of follow-up was 3.5 years (range, 0–12.5 years). ResultsMean access survival after taper reduction was 20.2 months (range, 0.10–94.4 months). Pre- and post-taper reduction access flows (mean Qb ± standard deviation) were 574 ± 315 ml/min and 929 ± 352 ml/min, respectively (P < .0001). The mean ratio of post- to pre-taper reduction flows was 1.6 (range, 1.1–10.2). No patients developed steal syndrome within 6 months after taper reduction. ConclusionsDialysis graft arterial anastomotic taper reduction did not result in the development of steal syndrome within 6 months. In the subset of patients who underwent flow measurements, taper reduction was associated with nearly a 2-fold improvement in access flow, which is a key predictor of access function.

End-stage renal disease meets end-of-the-line access

Ali et al1 have reported on a large series of prosthetic hemodialysis arterioarterial loop grafts constructed in complex and high-risk patients, with remarkable results. It is counterintuitive that the patency of relatively long prosthetic grafts in a limited outflow bed would be favorable, and also that relatively low-flow conduits with resistant outflow can achieve efficient dialysis. Indeed, their primary patency rate of 87.5% at 1 year and 62.5% at 2 years is far superior to most current reports for standard arteriovenous dialysis grafts.

Needle Directed Pulse Spray Pharmacomechanical Thrombolysis for Acute Thrombosis of Dialysis Fistulas – Technique, Efficacy and Short Term Follow UP

Background: The incidence of end stage renal disease is on the rise and most of these patients are undergoing dialysis either through tunnelled/non tunnelled dialysis catheters or through arteriovenous fistulas/grafts. The dialysis grafts and fistulas have limited durability of about 3 years and are more prone for thrombosis and stenosis. Catheter directed interventions are successful in establishing flow in most of the thrombosed fistulas, but require dedicated Cath lab and tertiary care centre. Needle directed thrombolysis is a novel economical, safe technique for thrombolysis of dialysis fistulas and grafts. The aim of the studt is to review the technique, safety, efficacy of needle directed pulse spray pharmacomechanical thrombolysis of dialysis fistulas and grafts with short term follow up. Subjects and Methods: This was a prospective observational study done in department of Radio diagnosis, Narayana medical college, Nellore. Selectively 25 patients with thrombosed AV fistulas were referred from nephrology OPD for needle directed thrombolysis to our department from December 2018 to May 2019. The procedure was performed on OPD basis in ultrasound procedure room. Regular Doppler follow up of patients is done up to 6 months. Results: Out of twenty five cases about seventeen cases (68%) were successful in achieving adequate recanalization in single session. four cases (16%) required repeat sessions of thrombolysis and were successful in second attempt. In four cases (16%) there was failure in attaining adequate recanalization due to marked multisegment attenuation/flow limiting stenosis of the draining vein. Conclusion: Needle directed Pulse spray pharmacomechanical thrombolysis is a novel technique, which can be done bedside, under portable ultrasound guidance and is an economical procedure as no intervention hardware is required. Continuous monitoring allows procedure to be stopped at the earliest once there is optimal recanalization, minimizing the systemic side effects of thrombolytic agents.

Percutaneous Endovascular Treatment of Stenosis of Dialysis Arteriovenous Fistulas

Background: The incidence of end stage renal disease is on the rise and most of these patients are undergoing dialysis either through tunneled/non tunneled dialysis catheters or through arteriovenous fistulas. The dialysis grafts and fistulas have limited durability of about 3 years and are more prone for thrombosis and stenosis, resulting in AVF dysfunction. As the number of access sites for dialysis is limited, percutaneous endovascular management by fistuloplasty has become the accepted first line of management to increase the lifespan of these fistulas.This article discusses a series of cases of AVF dysfunction secondary to draining vein stenosis managed by percutaneous transluminal angioplasty, their outcome and short term follow up till 3 months. The aim of the study is to review the role of percutaneous endovascular management of stenosis of dialysis fistulas, its indications, safety, efficacy and short term patency. Subjects and Methods: This was a prospective observational study done in department of Radio diagnosis, Narayana medical college, Nellore. About 20 cases were performed in our institution from December 2018 to August 2019. All these cases were done in angio suite after proper dialysis through temporary catheter. Post procedure doppler was done to evaluate the improvement in flow rate of these fistulas. Results: Seventeen cases were successful with immediate restoration of optimal flow rate during dialysis. (One case developed acute thrombosis of the fistula within 24 hours post procedure, which was successfully treated by needle directed thrombolysis with good patency at three month follow up). In two cases, there was failure of the procedure as the tight stenotic segment could not be negotiated. One case had early re-stenosis of the draining vein which required repeat session of fistuloplasty within one month with occlusion of the draining vein on three month follow up. Conclusion: Fistuloplasty is a minimally invasive percutaneous procedure with established safety and efficacy to restore the normal function of dialysis fistulae/grafts. The main aim of the procedure is to restore a diameter of the draining vein adequate for optimal flow rate during dialysis. Careful patient selection is required for increasing the success rate of the procedure. Repeat sessions of angioplasty is offered for re-stenosis to increase the lifespan of fistulas. Stent placement is usually avoided except for recurrent focal stenosis in precious fistulas.

Perioperative and long-term outcomes after percutaneous thrombectomy of arteriovenous dialysis access grafts

ObjectiveMaintenance of functional arteriovenous grafts (AVGs) for dialysis is difficult secondary to low primary patency, need for reinterventions, and limited alternative dialysis access options. We assessed our experience with percutaneous thrombectomy for treatment of occluded AVGs. MethodsWe performed a retrospective analysis of all percutaneous thrombectomies for AVGs from 2015 to 2017. These were generally performed using mechanical thrombectomy and occasional chemical tissue plasminogen activator thrombolysis, over-the-wire balloon embolectomy for inflow, and adjunctive inflow and outflow interventions as necessary. Perioperative outcomes, long-term patency, reinterventions, and need for new permanent access placement were analyzed. ResultsThere were 218 percutaneous thrombectomies performed on 86 AVGs in 77 patients. Approximately half (53.2%) of the patients were male and 68.8% were black. Mean age was 61.1 ± 13.0 years. At the time of thrombectomy, 73.8% underwent venous outflow interventions and 4.5% underwent arterial inflow interventions. Within 30 days, 24.8% of declotted grafts underwent repeated percutaneous thrombectomy, 14.3% required tunneled dialysis catheter placement, 4% developed minor access site or graft infections, and one patient underwent surgical arterial thrombectomy for arm ischemia. There were no venous thromboembolic, cardiopulmonary, or cerebrovascular complications or clinically significant pulmonary embolism. At 1 year and 3 years after percutaneous thrombectomy, freedom from repeated thrombosis was 37% and 18%, respectively, and freedom from new dialysis access placement was 66% and 51%, respectively. Overall patient survival was 82% at 3 years. ConclusionsPercutaneous thrombectomy of AVGs is safe and is associated with acceptable patency rates. This minimally invasive method extends AVG use for these high-risk patients with limited dialysis access options.