Percutaneous Treatment of Thrombosed Native Arteriovenous Dialysis Fistula Insufficiency: Efficacy of Mechanical Thrombectomy with Using the Stone Basket

PURPOSE: We wanted to evaluate the procedural success after percutaneous treatment of thrombosed native arteriovenous dialysis fistula insufficiency and the efficacy of performing mechanical thrombectomy with using the stone basket. MATERIALS AND METHODS: From March 2004 to June 2005, 36 thrombosed native hemodialysis access shunts in the upper limbs (brachiocephalic fistulas: 16 and radiocephalic fistulas: 20) were percutaneously treated in 30 patients. Declotting procedures were performed with using urokinase (100,000-200,000 unit) and manual catheter-directed thrombo-aspiration in all the patients. Angioplasty (6 mm in diameter and 4 cm in length) was performed at the identified area of the stenosis and/or with maceration of the thrombus. In 14 cases with massive thrombosis that was refractory to the above mentioned declotting procedures, mechanical thrombectomy with using a Wittich nitinol stone basket (Cook, Bloomington, IN) was performed. Data regarding the procedural success rate and the patency rate were analyzed by means of Fischer's exact test, and the Kaplan-Meier method with the Log-rank test was used for statistical inter-group comparisons between the brachiocephalic and radiocephalic fistulas. RESULTS: Successful declotting and restoration of thrill were achieved in 30 of 36 procedures (83%). Reestablishment of normal dialysis for at least one session was achieved in 29 of 36 procedures (81%). The procedural success rate for the brachiocephalic fistulas was 94% compared with 70% for the radiocephalic fistulas, but the difference was not statistically significant (p=0.104). In the cases with performing mechanical thrombectomy and using the stone basket, procedural success was achieved in 93% (13/14). The expected patency rates at 3, 6 and 12 months were 78%, 61% and 51%, respectively. The patency rates after declotting procedures were not significantly different between the brachiocephalic and radiocephlaic fistulas (p=0.871). CONCLUSION: Percutaneous treatment of thrombosed native arteriovenous dialysis fistula insufficiency showed an excellent success rate and patency rate, and especially performing mechanical thrombectomy with using the stone basket could increase the procedural success rate.

Metallic Stent Placement in Hemodialysis Graft Patients after Insufficient Balloon Dilation

OBJECTIVE: We wanted to report our experience of metallic stent placement after insufficient balloon dilation in graft hemodialysis patients. MATERIALS AND METHODS: Twenty-three patients (13 loop grafts in the forearm and 10 straight grafts in the upper arm) underwent metallic stent placement due to insufficient flow after urokinase thrombolysis and balloon dilation. The indications for metallic stent deployment included 1) recoil and/or kinked venous stenosis in 21 patients (venous anastomosis: 17 patients, peripheral outflow vein: four patients); and 2) major vascular rupture in two patients. Metallic stents 8-10mm in diameter and 40-80 mm in length were used. Of them, eight stents were deployed across the elbow crease. Access patency was determined by clinical follow-up and the overall rates were calculated by Kaplan-Meier survival analysis. RESULTS: No procedure-related complications (stent fracture or central migration) were encountered except for a delayed Wallstent shortening/migration at the venous anastomosis, which resulted in early access failure. The overall primary and secondary patency rates (+/- standard error) of all the vascular accesses in our 23 patients at 3, 6, 12 and 24 months were 69% +/- 9 and 88% +/- 6, 41% +/- 10 and 88% +/- 6, 30% +/- 10 and 77% +/- 10, and 12% +/- 8 and 61% +/- 13, respectively. For the forearm and upper-arm grafts, the primary and secondary patency rates were 51% +/- 16 and 86% +/- 13 vs 45% +/- 15 and 73%+/-13 at 6 months, and 25% +/- 15 and 71% +/- 17 vs 23% +/- 17 and 73% +/- 13 at 12 months (p = .346 and .224), respectively. CONCLUSION: Metallic stent placement is a safe and effective means for treating peripheral venous lesions in dialysis graft patients after insufficient balloon dilation. No statistically difference in the patency rates between the forearm and upper-arm patient groups was seen.

Efficacy of Percutaneous Transluminal Angioplasty for Treating Non-Maturing Brescia-Cimino Fistulas

PURPOSE: We wished to report our experiences for the treatment of non-maturing Brescia-Cimino fistulas by using percutaneous transluminal angioplasty (PTA). MATERIALS AND METHODS: From January 1997 and December 2003, we treated 22 patients with non-maturing Brescia-Cimino fistulas by using percutaneous transluminal angioplasty (PTA). A retrospective analysis was performed on the findings of the fistulograms, techniques and success rate of the PTA, and the patency rate. RESULTS: Seventeen segmental stenoses and 5 segmental occlusions of the cephalic veins were identified. Sixteen stenoses and 2 occlusions were located at the cephalic vein adjacent to the anastomosis site, and 3 occlusions and 1 stenosis are seen at the proximal vein near the elbow joint. In addition to venous stenosis, a focal arterial stenosis at the anastomosis site and two accompanying accessory veins that might hamper the maturation of main cephalic vein was seen in each of two patients, respectively, and the simultaneous occlusion of the left innominate vein as well as occlusion of the cephalic vein was noted in one patient. The initial success rate of the PTA procedures was 95.5% (21/22). The overall success rate including the 11 additional PTAs that were performed during follow-up was 96.9% (32/33). No major complication were noted to have occurred. The primary and secondary patency rates were 72% (16/22) and 95% (21/22) at 3 months, and 50% (11/22) and 77% (17/22) at 6 months, respectively. CONCLUSION: PTA is an effective and safe method for treating non-maturing Brescia-Cimino fistulas.

Percutaneous Intervention in the Management of Insufficient Native Arteriovenous Hemodialysis Fistulae

PURPOSE: To determine the effectiveness and patency of percutaneous intervention in insufficient native arteriovenous hemodialysis fistulae (AVFs). MATERIALS AND METHODS: Between March 1997 and September 2001, 67 cases of insufficient native AVF in 56 patients were treated by endovascular intervention. Except eight cases of insufficient native AVFs resulted from central vein lesion, PTA was performed in 48 cases, and thrombolytic therapy with or without PTA in 11. In eight of the cases, in which central vein stenosis had led to the insufficency, percutaneous transluminal angioplasty (PTA) was performed, and in three of the eight, a stent was inserted. Angiographic findings and complications, as well as success and patency rates in the non-thromobosis and thrombosis group, were evaluated; the central vein lesion group was analysed separately. RESULTS: Among 84 lesions observed at angiography, there were 54 cases of stenosis, 17 of occlusion, and 13 of combined thrombosis. The lesions were located in a proximal vein (n=51), distal vein (n=14), artery (n=6), and at the site of anastomosis (n=13). In the central vein lesion group (n=8), seven cases of stenosis and one of occlusion were noted. The overall procedural success rate was 79.1% (53/67). That is, in patients with no central vein lesion, the procedural success rate of PTA of native AVFs was 85.4% (41/48) and the patency rates of this were 83.1% at 6 months and 67.4% at 12 months. In cases of thrombolysis with/without PTA, the procedural success rate was 54.5% (6/11) and the patency rates were 83.3% at 6 months and 62.5% at 12 months. Finally, in patients with a central vein lesion, the procedural success rate was 75% (6/8) and the patency rates were 80% at 6 months and 30% at 12 months. There was one case of pseudoaneurysm formation at the puncture site of the brachial artery, which was used as the access route for intervention; one embolism in the brachial artery; and three cases of vascular spasm and two of hematoma which did not require active treatment. CONCLUSION: Percutaneous intervention offers effective and safe management of insufficient AVFs. The procedural success rate was higher for stenosis than for thrombotic occlusion.

Percutaneous Mechanical Declotting of Thrombosed Dialysis Graft

PURPOSE: To evaluate the effectiveness of percutaneous mechanical declotting in thrombosed dialysis graft. MATERIALS AND METHODS: Thirty-two patients with thrombosed dialysis graft in 260 cases involving insufficient hemodialytic access underwent mechanical declotting. Using a 7-F Desilets-Hoffman sheath and the crossed-catheter technique, we aspirated the intragraft clot and pushed the residual clot into the central circulation with balloon catheters. The success rate, procedure time, complications and patency rates were evaluated. RESULTS: Technical success was achieved in 24 of 32 cases, with a procedure time of 30 -240 (average, 111) minutes. In five of eight cases in which technical failure occurred, the guide wire failed to reach the stenotic site and in the other three, there was insufficient luminal dilatation. Complications included vein ruptures (n=2), arterial emboli (n=1) and arterial dissection (1), but there was no evidence of clinical symptoms of pulmonary embolism. The six-month patency rate was 67.8%. CONCLUSION: Mechanical declotting of thrombosed dialysis graft using a balloon catheter is relatively inexpensive, safe and fast, and is well tolerated.

The Usefulness of Wire-Loop Technique for Percutaneous Angioplasty of Insufficient Hemodialysis Fistula

PURPOSE: To evaluate the usefulness of the Wire-Loop technique, used to perform percutaneous transluminal angioplasty (PTA) in occluded arteriovenous fistula when standard methods fail to pass the balloon catheter. MATERIALS AND METHODS: In 30 patients [M:F=14:16; aged 27 -77 (mean, 51.3) years], the Wire-Loop technique was used to perform percutaneous transluminal angioplasty of insufficiently hemodialysed arteriovenous fistula where a balloon catheter had failed to pass through the stenotic lesion after a guide wire had successfully passed. Native and Goretex fistula were used in 22 and eight cases, respectively. Sixteen stenoses were located in the central vein, and fourteen in the peripheral. The punture sites used in order to perform the technique were the femoral vein in all cases of central stenosis; three basilic, four cephalic, and five femoral veins in cases of peripheral stenosis and one femoral and one radial artery in cases of anastomotic stenosis. The guide wire was passed through the stenotic lesion, pulled out using the snare technique, and then stretched in order to tighten it. The balloon catheter was then passed through the lesion and traditional balloon angioplasty was performed. The technical success rate and complications of the technique, and the patency rate of recanalized arteriovenous fistula, were evaluated. RESULTS: In 26 of the thirty patients, (86.7%), the procedure was technically successful. In the remaining four cases, failure was due to venous dissection (n=1), marked residual stenosis (n=2), or cardiac arrest (n=1) during the procedure. The average procedure time was 105 (range, 40 -210) minutes, and in three cases rupture of the vein occurred. The patency rate of PTA was 80% (24/30) at four months, 63% (19/30) at six months, and 30% (9/30) at twelve months. The expected technical success rate of traditional PTA, without the Wire-Loop technique, would have been 79.3%, but using the technique, the rate increased to 86.7%. CONCLUSION: The Wire-Loop technique appears to be a safe and valuable procedure in patients with insufficiently hemodialysed arteriovenous fistula, and is therefore useful in cases in which traditional PTA fails.

Hemodialysis Shunts-related Subclavian Vein Stenosis: Treatment with Self-expandable Metallic Stent

PURPOSE: To evaluate the usefulness of placement of self-expandable stents in hemodialytic shunt-relatedsubclavian vein stenosis. MATERIALS AND METHODS: Self-expandable metallic stent was placed in nine patients withhemodialytic shunt-related subclavian vein stenosis. In seven cases, angioplasty was attempted before stentplacement; in five, stents were placed immediately after failed angioplasty; and in two, due to restenosis afterangioplasty. Procedures involved a 10mm diameter, 7-10cm length Wallstent in eight cases, and a 10mm diameter, 8cm length Hanaro stent in one. In all cases, clinical follow-up, which included physical examination and themeasurement of venous resistance pressure during hemodialysis, was performed. The follow-up period was between 5months and 1 year 7 months. Repeated intervention was performed if restenosis was detected. RESULTS: The stenoticsites were in eight cases the site of a previous subclavian venous line, and in one, the site of anatomicnarrowing at the thoracic inlet of the subclavian vein. The technical success rate was 100%; a resultingcomplication was stent migration into the right atrium in one case in which a Hanaro stent had been used; this wasremoved by snaring. During follow-up of the eight patients in whon stent placement was successful, restenosisdeveloped in three cases. This occurred during the 7th, 8th, and 15th month, respectively. Two such cases weretreated by balloon dilatation. CONCLUSION: In hemodialytic shunt-related subclavian vein stenosis, treatmentinvolving the use of a self-expandable metallic stent is useful, especially for treating a lesion which has notresponded to angioplasty with a high patency rate.

Effect of Percutaneous Transluminal Angioplasty in insufficiency of Arteriovenous Fistula for Hemodialysis

PURPOSE: To evaluate the effectiveness of percutaneous transluminal angioplasty(PTA) and to determine thefactors affecting the long-term patency rate in the management of insufficient hemodialytic arteriovenousfistula(AVF). MATERIALS AND METHODS: Forty-nine cases of insufficient hemodialytic AVF were treated in 44patients(native AVF:20, graft AVF:29, M:17, F:27, Age:22-70 years). In 28 thrombus patients, thrombolysis wasperformed with urokinase, and was followed by PTA. The initial success rate and complications of PTA wereevaluated. According to the site and length of the stenosis, type and age of the AVF, the presence or abscence of thrombus, a history of diabetic mellitus, the patient 's age, and the duration of renal failure, patency rateswere compared within each subgroup using the Kaplan-Meier logrank test. RESULTS: The initial success rate of PTAfor insufficient hemodialytic AVF was 88%(43/49), the patency rate of PTA was 67% at 6 months, and 50% at 12months. The initial success rate of thrombolysis was 89%(25/28). The complication rate of PTA was 12%(6/49), ofwhich five cases were vein rupture, and one was subcutaneous hematoma. Statistically, the patency rates in theabove mentioned subgroups were not significantly different. CONCLUSION: PTA with or without thrombolysis offerssafe and effective management of insufficient hemodialytic AVF.

Percutaneous Transluminal Angioplasty and Stent Insertion in Central Venous Steno-occlusion

PURPOSE: To evaluate the efficacy of percutaneous transluminal angioplasty (PTA) and stent insertion incentral venous steno-occlusion. MATERIALS AND METHODS: Between August 1992 and January 1998, 11 patients with symptomatic central venous steno-occlusion(six stenoses and five occlusions) underwent pereutaneous treatment. Eleven PTAs were performed and stents were introduced in two patients because of incomplete PTA. During follow-up, a total of eight revisions were performed in five patients with recurrence(six stenoses and two occlusions). Success and long term patency rates were evaluated. The length and degree of the lesion and degree of residualstenosis, as well as pressure gradient through the lesion and decrease of the gradient after PTA, were correlated with patency rates. Complications during the procedures and follow-up period were evaluated. RESULT: The overall success rate was 89.5%; those of primary and revision intervention were 90.9% and 87.5%, respectively. Primary and revision patency rates were 72.7% and 50%, respectively, at 6 months, and 40% and 25% at 12 months. In five patients who underwent revision, primary and secondary patency rates were 80% and 100% at 6 months, 40% and 80% at 12 months, and 0% and 60% at 18 months. Only reduction of the pressure gradient after PTA correlated significantly with patency rates. No significant complications observed during the procedures follow-up period. CONCLUSION: PTA and stent insertion is effective for the treatment of central venous steno-occlusion.

Interventional Recanalization of Artificial Arteriovenous Fistula and Graft for Hemodialysis: Angioplasty andPulsed-Spray Thrombolysis with Urokinase

PURPOSE: To evaluate the effectiveness of percutaneous transluminal angioplasty (PTA) and pulsed-spraypharmacomechanical thrombolysis (PSPMT) using urokinase for the management of insufficient hemodialysis access. MATERIALS AND METHODS: Between September 1996 and May 1998, 21 insufficient hemodialysis accesses were treated in16 patients (3 artificial arteriovenous fistulae, AVF ; and 13 arteriovenous graft, AVG). PTA and PSPMT were performed in 6 and 15 and 15 cases, respectively, and success and long-term patency rates were evaluated. RESULTS: The overall success rate of PTA and PSPMT for insufficient hemodialysis access was 76.2%(16/21). The success rates of PTA and PSPMT were 83.3%(5/6) and 73.3%(11/15), respectively. the primary patency rates of PSPMT were 69+/-12.8% at 6 months and 38+/-18.6% at 12 months. One of the two initially successful PTAs had been patent for 7months, and the second PTA was performed at that time due to venous stenosis. The other was patent for 15 months throughout the follow-up period. CONCLUSION: PTA and PSPMT are effective primary methods for the treatment of insufficient hemodialysis access ; success and patency rates were high, and the procedures can be performed repeatedly.

Radiologic Findings of Pulmonary Endometriosis

PURPOSE: To evaluate the effectiveness of percutaneous transluminal angioplasty (PTA) and pulsed-spraypharmacomechanical thrombolysis (PSPMT) using urokinase for the management of insufficient hemodialysis access. MATERIALS AND METHODS: Between September 1996 and May 1998, 21 insufficient hemodialysis accesses were treated in 16 patients (3 artificial arteriovenous fistulae, AVF ; and 13 arteriovenous graft, AVG). PTA and PSPMT were performed in 6 and 15 and 15 cases, respectively, and success and long-term patency rates were evaluated. RESULTS: The overall success rate of PTA and PSPMT for insufficient hemodialysis access was 76.2%(16/21). The success rates of PTA and PSPMT were 83.3%(5/6) and 73.3%(11/15), respectively. the primary patency rates of PSPMT were 69+/-12.8% at 6 months and 38+/-18.6% at 12 months. One of the two initially successful PTAs had been patent for 7months, and the second PTA was performed at that time due to venous stenosis. The other was patent for 15 months throughout the follow-up period. CONCLUSION: PTA and PSPMT are effective primary methods for the treatment of insufficient hemodialysis access ; success and patency rates were high, and the procedures can be performed repeatedly.

Percutaneous Transluminal Angioplasty and Thrombolysis in the Management of Insufficient Hemodialysis Access: Long-Term Patency Rates and Factors Affecting Patency Rates

PURPOSE: To evaluate the success rates, long-term patency rates and factors affecting the patency rates of percutaneous transluminal angioplasty (PTA) and thrombolysis in the management of insufficient access during hemodialysis. MATERIALS AND METHODS: Between January 1991 and March 1995, 37 insufficient shunts (23 native fistulae and 14 graft fistulae) were treated in 31 patients. PTA was performed in 24 shunts, and thrombolysis in13; in seven of these latter, thrombolysis was followed by PTA. The success and long-term patency rates of PTA and thrombolysis were evaluated. Shunts were subdivided according to a patient's age, type and age of the shunt, and number and length of the stenosis, and the degree of residual stenosis and in each subgroup, patency rates was compared. RESULTS: The overall success rate of PTA and thrombolysis for insufficient hemodialytic access was 78.4% (29/37). The success rates of PTA and thrombolysis were 91.7% (22/24) and 53.8% (7/13), respectively. The patency rates of PTA (85.7% at 6 months, 78.6% at 12 months, and 55.9% at 24 months) were superior to those of thrombolysis (100% at 6 months and 0% at 12 months) (p=.014). Patency rates in each subgroup were not significantly different (p>.05). CONCLUSION: The success and patency rates of PTA were superior to those of thrombolysis, and after PTA or thrombolysis, no factors affected patency rates.