Never too old for an autogenous dialysis fistula? Results of endovascular interventions in nonagenarians.

The number of elderly patients in hemodialysis has increased in recent years and nowadays there are significant numbers of nonagenarians. However, there is currently no information in the literature about arteriovenous fistula (AVF) outcomes in patients aged over 90 years after endovascular treatment for stenosis or thrombosis. This retrospective analysis of prospectively collected data included 38 consecutive patients aged over 90 years who were referred for endovascular evaluation and treatment of AVF nonmaturation (n = 11), dysfunction (n = 25), or thrombosis (n = 2) between 2005 and 2013. Median age was 93.9 years, and 24% were diabetic and 47% hypertensive patients. Immature and dysfunctional AVFs were treated by angioplasty, thrombosed fistulas by thromboaspiration. Fistula patency rates were calculated according to the Life-Table method. The immediate overall clinical success rate was 97.4%. Complications included four transient dilation-induced ruptures. Stents were placed for rupture control (n = 3) and major elastic recoil (n = 3), and to rectify a basilic vein pseudoaneurysm developed after dilation. Mean follow-up was 62.6 months. Primary patency rates were 60% and 43% at 1 and 2 years, respectively. Secondary patency rates were 95% and 92% at 1 and 2 years, respectively. Patency rates were not significantly different between immature and dysfunctional AVFs. Endovascular treatment of AVF complications appears to be a valuable approach in nonagenarian patients in view of the low invasiveness, low complication rate, and relatively good long-term patency rates.

Mechanical enhancement of AVF maturation.

A native arteriovenous fistula (AVF) should be systematically evaluated at 4 to 6 weeks after creation. Any clinical indications of nonmaturation should be promptly followed up and confirmed by detailed duplex ultrasonography looking for a deep vein or inadequate access flow due to stenoses. Once vein depth has been ruled out, a significant stenosis is invariably identified and should therefore be operated on or dilated. Predilation angiography should be performed preferably through the brachial artery. Arterial lesions are frequent causes of nonmaturation of forearm AVFs and should therefore be dilated. The best results are obtained when the juxta-anastomotic vein and the feeding artery are dilated with 6 and 4 mm dilation balloons, respectively. Our opinion is that there is no or only the very rare indication for ligation or embolization of collaterals. Rupture of the weak venous or arterial wall is common (15% of cases), the majority of which can be managed with prolonged balloon tamponade. Nonmaturing AVFs are ideally needled only 7 to 14 days after successful dilation to allow hematomas caused by cannulation and local anesthesia to resorb. Including initial failures, 1-year primary and secondary patency rates reported by interventional radiologists range from 34% to 39% and 68% to 79%, respectively. Results after dilation of diseased radial arteries feeding normal veins are even better, with primary patency rates ranging for 65% to 83%, and secondary patency rates of over 90%. Using an aggressive and multidisciplinary treatment strategy, nonmaturing dialysis fistulas can be identified, evaluated and salvaged with angioplasty.

Monitoring dialysis arteriovenous fistulae: it's in our hands.

Vascular access problems are a daily occurrence in hemodialysis units. Loss of patency of the vascular access limits hemodialysis delivery and may result in underdialysis that leads to increased morbidity and mortality. Despite the known superiority of autogenous fistulae over grafts, autogenous fistulae also suffer from frequent development of stenosis and subsequent thrombosis. International guidelines recommend programmes for detection of stenosis and consequent correction in an attempt to reduce the rate of thrombosis. Physical examination of autogenous fistulae has recently been revisited as an important element in the assessment of stenotic lesions. Prospective observational studies have consistently demonstrated that physical examination performed by trained physicians is an accurate method for the diagnosis of fistula stenosis and, therefore, should be part of all surveillance protocols of the vascular access. However, to optimize hemodialysis access surveillance, hemodialysis practitioners may need to improve their skills in performing physical examination. The purpose of this article is to review the basics and drawbacks of physical examination for dialysis arteriovenous fistulae and to provide the reader with its diagnostic accuracy in the detection of arteriovenous fistula dysfunction, based on current published literature.

An unusual case of central venous catheter-related bacteremia.

Some hemodialysed patients need definitive central venous catheterization. One of the main complications is catheter infection, and each infection must be treated. We report a case of an unusual cause of central venous catheter (CVC) infection: physical examination and catheter opacification demonstrated two pin-holes in the catheter. It was possible to salvage the catheter following a treatment regimen combining systemic antibiotics, antibiotic locks, fibrinolytics, and removal of a catheter segment.

Comparative outcomes of treated symptomatic versus non-treated asymptomatic high-grade central vein stenoses in the outflow of predominantly dialysis fistulas.

BACKGROUND: Witholding treatment in asymptomatic/pauci-symptomatic high-grade central vein stenosis (CVS), i.e. those not causing debilitating painful extremity oedema, the benefits of which have been shown in only one study in grafts, is debatable. The aim of our study was to assess the short- and long-term benefits of such a strategy in mainly autogenous fistulas. METHODS: We retrospectively compared the outcomes of 53 untreated asymptomatic/pauci-symptomatic and 50 symptomatic high-grade CVS treated by dilation with or without stenting between January 1998 and August 2010 at a single center. Central vein and access patency was estimated by Kaplan-Meier analysis. RESULTS: Mean age, central catheter use and location of stenosis (brachiocephalic vein) in asymptomatic/pauci-symptomatic and symptomatic CVS were significantly different at 69 versus 75 years, 28 versus 48% and 74 versus 56%, respectively. Ninety percent of the cases had an autogenous fistula. The mean degree of stenosis was >80%. Fourty percent of asymptomatic/pauci-symptomatic CVS became severely symptomatic after 4 years. Primary central vein patency at 3, 12, 24 and 36 months in asymptomatic/pauci-symptomatic and symptomatic CVS were 87±5 versus 82±6, 77±6 versus 55±9, 71±7 versus 35±9 and 67±7 versus 18±9%, respectively (P=0.002). Primary access circuit patency rate was not significantly different between the two groups with 66±5 versus 50±4% at 1 year. Secondary central vein and access circuit patency rates at 1 and 3 years were 100 and 93±7 versus 89±5 and 84±7% (P=0.014). CONCLUSIONS: Withholding treatment in asymptomatic/pauci-symptomatic CVS in dialysis fistulas yielded significantly better short- and long-term central vein patency than treatment of symptomatic cases without detrimental effects on overall dialysis circuit.

Placement of wrist ulnar-basilic autogenous arteriovenous access for hemodialysis in adults and children using microsurgery.

OBJECTIVES: The distal basilic forearm vein is frequently preserved and might be used more frequently for placement of an ulnar-basilic autogenous arteriovenous access (UB-AAVA) in the wrist despite the small size of the two vessels. The scarcity of publications led us to initiate a prospective study regarding the placement and outcomes of UB-AAVAs. METHODS: Seventy patients (63 adults, seven children) with no usable cephalic vein in either forearm were selected consecutively over 4 years for placement of a UB-AAVA. The prerequisite was a clinically visible or palpable forearm basilic vein after placing a tourniquet. Regional anesthesia, prophylactic hemostasis, and a surgical microscope were used systematically. Secondary superficialization was performed in two patients. Most non-matured accesses were abandoned in favor of the placement of a more proximal autogenous access. Mean follow-up was 20 months (SD =15). RESULTS: Immediate patency was obtained in 94% of adults and 100% of children. Success (in-use access) was achieved in 60% of patients (38/63 adults and 6/7 children) after a mean postoperative interval of 80 days (SD = 64; range, 31-277). Failures included four immediate thromboses, one postoperative death, and 21 never-matured accesses. No steal syndrome was observed. Initial failures included, primary patency rates in adults at 1 and 2 years were 42% ± 6% and 30% ± 7%, respectively; secondary patency rates at 1 year and 2 years were 60% ± 6% and 53% ± 7%, respectively. CONCLUSIONS: Although patency rates are not as good as those achieved with radial cephalic-AAVA, the UB-AAVA is an alternative autogenous forearm access before the placement of any other access involving the basilic vein. The use of the surgical microscope is mandatory, and more than usual time is required to achieve maturation.

Management of perianastomotic stenosis of direct wrist autogenous radial-cephalic arteriovenous accesses for dialysis.

OBJECTIVE: Radial-cephalic fistulas (RCFs) perianastomotic stenoses (PASs) are on and around the fistula anastomosis. This group of lesions encompasses juxta-anastomotic stenosis (stenosis located on the venous side within 3 cm away from the anastomosis), anastomotic, and arterial stenosis. The purpose of our study was to assess the postintervention primary patency and assisted postintervention primary patency (APP) rates for surgery and angioplasty when treating these stenoses. The secondary endpoint was to identify factors that might influence the procedure's patency rates. MATERIALS AND METHODS: This retrospective study included 73 consecutive patients treated for lack of maturation PASs between January 1999 and December 2005 in two interventional centers. Patients' mean age was 65 years old. Stenoses were treated by surgery (n = 21) or percutaneous transluminal angioplasty (PTA; n = 52). Surgery meant creation of a new anastomosis excluding the area of stenosis. Preoperative characteristics including the patient's age, gender, comorbidities, stenosis location, and length were not statistically different between the two groups. The mean follow-up was 39 months for PTA and 49 months for surgery. RESULTS: Anatomical and clinical success rates were 86% and 90% for surgery, and 75% and 92% for PTA. At 1 year, the primary patency rates were 71 ± 10% for surgery and 41 ± 6% for PTA, respectively (P < .02). There was no significant difference between the two groups with respect to assisted primary patency (95% vs 92%). In the PTA group, stenosis location at the anastomosis itself was a risk factor of early recurrence (P = .047). The complication rate was similar between surgery and PTA. CONCLUSION: Our results suggest that the treatment of anastomotic stenoses should be surgical rather than endovascular. Angioplasty and surgery have shown similar results when used to treat other perianastomotic stenoses, but repeat procedures were more frequent with angioplasty.

Endovascular treatment of immature, dysfunctional and thrombosed forearm autogenous ulnar-basilic and radial-basilic fistulas for haemodialysis.

BACKGROUND: Forearm basilic fistulas are rarely used as vascular accesses for haemodialysis but they represent a valuable option when autogenous radial-cephalic fistulas cannot be performed. There is no information in the literature to date about the outcome of direct ulnar-basilic or transposed radial-basilic forearm autogenous fistulas after endovascular treatment of stenosis or thrombosis. METHODS: This retrospective study included 78 consecutive patients from eight dialysis units who were referred to a single interventional radiology centre for endovascular treatment of delayed maturation (n = 30), dysfunction (n = 35) or thrombosis (n = 13) of their autogenous forearm ulnar-basilic (n = 62) or radial-basilic fistulas (n = 16). The male/female ratio was 54/24, mean age was 64.7 years, 26% had diabetes, 83% were treated for hypertension and the mean body mass index was 24 kg/m(2). Immature and dysfunctional fistulas were treated by dilation and thrombosed fistulas by aspiration thrombectomy. Clinical success was defined as the perception of a continuous palpable thrill and the ability to perform dialysis. Fistula patency rates were calculated with the Kaplan-Meier method. RESULTS: Overall primary patency rates were 51% and 44% at 1 and 2 years, respectively. These rates were lower for immature and thrombosed fistulas compared to dysfunctional mature fistulas. Secondary patency rates were 96% and 91% at 1 and 4 years, respectively. Immediate overall clinical success was 97%. The two failures occurred with an immature and a thrombosed fistula. Immediate complications included two transient dilation-induced ruptures treated by prolonged balloon inflation. One case of subsequent hand ischaemia was successfully treated by distal artery ligation. CONCLUSIONS: Endovascular treatment plays a major role in the maturation process, maintenance and salvage of radial and ulnar-basilic fistulas. The preservation of upper arm veins for the future, with low risk of hand ischaemia or hyperflow, might encourage nephrologists and surgeons to consider forearm basilic fistulas systematically in their strategy of vascular access creation.

Percutaneous dilation of the radial artery in nonmaturing autogenous radial-cephalic fistulas for haemodialysis.

BACKGROUND: Delayed maturation of radial-cephalic fistulas can be due to lesions of the radial artery that are amenable to percutaneous dilation. METHODS: Over a period of 7 years, 74 consecutive patients underwent angiography of an immature fistula that showed either stenosis or an insufficient enlargement of the radial artery that was treated by percutaneous dilation. Success, complications and secondary interventions were recorded according to consensus definitions. Patency following angioplasty was estimated with the Kaplan-Meier technique. RESULTS: The mean patient age was 70 years, 44% were women, 69% had diabetes, 23% were smokers, 76% had hypertension, 64% had coronary disease and 46% had peripheral artery occlusive disease. Concomitant venous stenosis was diagnosed in 53% of patients. Arterial stenosis was >5 cm long in 53 cases. Technical success was achieved in 73/74 cases following angioplasty. All but two fistulas were then successfully used for dialysis. Dilation-induced rupture occurred in 13 cases (17%) but required only two stent placements. Five cases (7%) of hand ischaemia within 1 month of dilation were treated successfully by ligation of the distal artery. Primary patency rates at 12 and 24 months were significantly better for pure arterial lesions, with 65% and 61% compared to 42% and 35% in cases of concomitant venous stenosis (P < 0.04). The secondary patency rates were 96% and 94% at 1 and 2 years, respectively. CONCLUSION: Dilation of the radial artery yields higher patency rates than for veins. Surgeons might therefore be less demanding about the initial quality of the radial artery prior to creation of radial-cephalic fistulas.

Lipectomy as a new approach to secondary procedure superficialization of direct autogenous forearm radial-cephalic arteriovenous accesses for hemodialysis.

BACKGROUND: The depth of veins can discourage surgeons from creating radial-cephalic arteriovenous accesses for hemodialysis in obese patients. Elevation and tunneled transposition are the two techniques that have been described to superficialize these veins and make them accessible for cannulation. Unfortunately, such manipulation of veins has potential drawbacks. We report lipectomy, a new technique that removes subcutaneous fat and does not mobilize the vein. METHODS: This single-center prospective study included 49 consecutive patients (17 men, 32 women) who underwent second-stage lipectomy after creation of a radial-cephalic fistula. Mean patient age was 54 years, 36% had diabetes, and the mean body mass index was 31 +/- 5.6 kg/m(2). Subcutaneous fatty tissues were removed after two transverse skin incisions under regional anesthesia and preventive hemostasis. Cannulation was first allowed 1 month later, after clinical and color duplex ultrasound evaluation. Technical success was defined as the ability to remove the fat and to palpate the patent vein immediately under the skin at the end of the operation. Clinical success was defined as the ability to perform at least three consecutive dialysis sessions with two needles. All patients were checked systematically every 6 months by the surgeon. RESULTS: Technical and clinical success rates were 96% (47 of 49) and 94% (46 of 49), respectively. Mean vein depth decreased from 8 +/- 2 to 3 +/- 1 mm according to duplex ultrasound imaging. The mean vein diameter increased from 6 +/- 1 to 8 +/- 2 mm. In one patient, vein tortuosity that was overlooked required conventional repeat tunneling. One extensive hematoma resulted in loss of the fistula. One patient died before the fistula could be used. Primary patency rates were 71% +/- 7% and 63% +/- 8% at 1 and 3 years, respectively, and secondary patency rates were 98% +/- 2% and 88% +/- 7%. Delayed complications were treated by surgery (n = 7) or by endovascular procedures (n = 10). CONCLUSION: Lipectomy is a safe, effective, and durable approach to make deep arterialized forearm veins accessible for routine cannulation for hemodialysis in obese patients. It might even be hypothesized that incident obese dialysis patients will eventually have the highest proportion of radial-cephalic fistulas because they often have distal veins that have been preserved by their fat from previous attempts at cannulation for blood sampling or infusion.

Transposition of radial artery for reduction of excessive high-flow in autogenous arm accesses for hemodialysis.

OBJECTIVE: All surgical methods published to date for the reduction of excessive high-flow in native elbow fistulas for dialysis have limitations. We report a new surgical approach to flow reduction by transposition of the radial artery to the elbow level. METHODS: From 1992 to 2008, 47 consecutive patients (22 women) with brachial artery to elbow vein autogenous fistula underwent flow reduction via replacement of brachial artery by transposed distal radial artery inflow. Fistulas were side-to-end either brachial-cephalic (19) or brachial-basilic (28). The indications were hand ischemia (4), cardiac failure (13), concerns about future cardiac dysfunction (23), and chronic venous hypertension resulting in aneurysmal degeneration of the vein (7). Mean patient age was 44 years, 11% were diabetic, 17% were smokers, and mean BMI was 22. Mean fistula age before flow reduction was 2.5 years. RESULTS: Technical success was 91% (43 of 47). The mean flow rate dropped by 66% +/- 14%. Clinical success in symptomatic patients was 75% (18 of 24). The fistula eventually had to be ligated in three cases of cardiac failure because of insufficient clinical improvement. All four patients with hand ischemia were cured, with no recurrence during follow-up. Primary patency rates at one and three years were 61% +/- 7% and 40% +/- 8%. Secondary patency rates at one and three years were 89% +/- 5% and 70% +/- 8%. CONCLUSION: Transposition of the radial artery, a safe and effective technique, might now be considered in the surgical armamentarium of flow reduction techniques.

Declotting a thrombosed Brescia-Cimino fistula by manual catheter-directed aspiration of the thrombus.

Acute thrombosis of native fistulae for hemodialysis occurs more rarely than for prosthetic grafts. The vascular access should be reopened as soon as possible in order to resume regular dialysis and to avoid resorting to a temporary central line. Manual aspiration is one of the numerous methods described in this setting. Clinical examination is essential to rule out local infection, which is the only serious contraindication to percutaneous maneuvers. Two introducer-sheaths are placed in a criss-cross fashion in order to gain access to the venous outflow and to the anastomosis. Access to the venous outflow is performed first in order to check the proximal extent of the thrombosis. Heparin and antibiotics are injected systemically. A similar maneuver is then performed in the direction of the anastomosis. The aspiration phase is then initiated. A 7-9 Fr aspiration catheter is pushed through the "venous" introducer. Manual aspiration is created through a 50 ml syringe while the catheter is progressively removed with back and forth movements. The catheter and the contents of the syringe are flushed through a gauze on the working table to evaluate the amount of thrombus which has been removed and the maneuver is repeated as often as necessary to remove all the thrombus. Once all the clots located downstream from the venous introducer have been removed, any unmasked underlying stenosis is NOT dilated at this stage since it provides protection against major embolism coming from the inflow. The aspiration catheter is then pushed through the "arterial" introducer down to the anastomosis in order to aspirate the thrombus located between the tip of the introducer and the anastomosis. Dilatation of unmasked stenoses is finally performed using high-pressure balloons. The holes made by the two introducers are closed using a U-shaped suture with interposition of a short piece of plastic and the patient is sent back to the nephrologists for dialysis.