Percutaneous treatment of complications occurring during hemodialysis graft recanalization

INTRODUCTION/OBJECTIVE: To describe and evaluate percutaneous treatment methods of complications occurring during recanalization of thrombosed hemodialysis access grafts. METHODS AND MATERIALS: A retrospective review of 579 thrombosed hemodialysis access grafts revealed 48 complications occurring during urokinase thrombolysis (512) or mechanical thrombectomy (67). These include 12 venous or venous anastomotic ruptures not controlled by balloon tamponade, eight arterial emboli, 12 graft extravasations, seven small hematomas, four intragraft pseudointimal 'dissections', two incidents of pulmonary edema, one episode of intestinal angina, one procedural death, and one distant hematoma. RESULTS: Twelve cases of post angioplasty ruptures were treated with uncovered stents of which 10 resulted in graft salvage allowing successful hemodialysis. All arterial emboli were retrieved by Fogarty or embolectomy balloons. The 10/12 graft extravasations were successfully treated by digital compression while the procedure was completed and the graft flow was restored. Dissections were treated with prolonged Percutaneous Trasluminal Angioplasty (PTA) balloon inflation. Overall technical success was 39/48 (81%). Kaplan-Meier Primary and secondary patency rates were 72 and 78% at 30, 62 and 73% at 90 and 36 and 67% at 180 days, respectively. Secondary patency rates remained over 50% at 1 year. There were no additional complications caused by these maneuvers. DISCUSSIONS AND CONCLUSION: The majority of complications occurring during percutaneous thrombolysis/thrombectomy of thrombosed access grafts, can be treated at the same sitting allowing completion of the recanalization procedure and usage of the same access for hemodialysis.     

Early rethrombosis of clotted hemodialysis grafts: graft salvage achieved with an aggressive approach

OBJECTIVE: The purpose of this study was to assess the efficacy of repeated pulsed spray pharmacomechanical thrombolysis for salvage of early rethrombosis of hemodialysis grafts and to identify factors that predict successful outcome. MATERIALS AND METHODS: Thirty-four patients with initial successful thrombolysis were referred for repeated thrombolysis because of early rethrombosis. Repeated thrombolysis occurred within 1 month of initial thrombolysis. Technical success and patency rates were calculated. Causes of graft thrombosis and procedural modifications were analyzed. RESULTS: The 39 rethrombosed grafts were successfully treated using pharmacomechanical thrombolysis, and patients underwent subsequent hemodialysis. The underlying flow-limiting stenoses were treated with balloon angioplasty using a larger balloon (41%), a same-size angioplasty balloon (18%), stent placement (15%), or increased anticoagulation (5%). A new stenosis location was discovered in 18%. Mean primary patency was 80.9 days (2.6 months) and secondary patency was 235.4 days (7.8 months). With life table analysis, 1-, 3-, 6-, and 12-month primary patency rates were 72%, 31%, 23%, and 15%, and secondary patency rates were 77%, 62%, 51%, and 31%, respectively. Graft patency rates in our study were compared with our institutional historic graft patency rates, with no significant difference noted (p = 0.76). No major procedural complications occurred. CONCLUSION: Adequate technical success and patency rates for pharmacomechanical thrombolysis occur even for hemodialysis grafts that rethrombose within 1 month. After thrombolysis, aggressive search for and treatment of additional stenoses are warranted.     

Prophylactic angioplasty reduces thrombosis in virgin ePTFE arteriovenous dialysis grafts with greater than 50% stenosis: subset analysis of a prospectively randomized study

PURPOSE: To determine if prophylactic percutaneous transluminal balloon angioplasty (PTA) can extend patency in functioning virgin ePTFE arteriovenous hemodialysis grafts. MATERIALS AND METHODS: The results of a prospectively randomized study of 64 patients with greater than 50% stenosis of functioning ePTFE arteriovenous hemodialysis grafts who were blindly assigned to be treated with PTA (treatment group) or observed without treatment (control group) were subjected to statistical subset analysis. Within this group were 21 patients (virgins) who had never undergone surgery, PTA, or thrombolysis. Eight patients had been assigned to the treatment group and 13 to the control group. The virgin groups were well matched as to age, sex, and risk factors. The virgin treatment group versus virgin control group had 1.63 versus 1.46 stenoses per patient and 61.3% versus 63.3% average percentage stenosis per lesion, respectively. Stenoses were treated with PTA 27 times (average, 3.4 per patient) in the virgin treatment group. Primary study patency began at the time of randomization and ended with graft thrombosis or nonfunction. RESULTS: Among the 32 patients randomized to treatment with PTA, study patency was significantly increased (P > .0001) and the incidence of graft thrombosis significantly decreased (P = .0151) in the eight-patient virgin subset when compared with the 24-patient nonvirgin subset of the treatment group. During the 81.3 patient-dialysis-year study period, patency in the virgin-treatment versus virgin-control groups, respectively, was terminated by thrombosis in two versus nine, by death in two versus two, and cadaveric renal transplant in one versus zero. There was a statistically significant prolongation of study patency (P = .0349) and a reduction of graft thromboses, 0.10 versus 0.44 thromboses per patient-dialysis year, in the virgin-treatment group compared to the virgin-control group. CONCLUSION: Patency after PTA of ePTFE hemodialysis grafts is significantly affected by previous interventions. Prophylactic PTA of stenoses greater than 50% in functioning virgin ePTFE arteriovenous hemodialysis grafts can significantly extend their patency. PTA should be included as an important treatment option in this patient population.     

Cutting balloon percutaneous transluminal angioplasty for salvage of lower limb arterial bypass grafts: feasibility

PURPOSE: To evaluate the feasibility of cutting balloon percutaneous transluminal angioplasty (PTA) for treatment of neointimal hyperplasia in peripheral arterial bypass grafts. MATERIALS AND METHODS: Fifteen consecutive patients (six women, nine men; age range, 57-89 years; mean age, 71 years) were treated with cutting balloon PTA for 16 anastomotic stenoses after infrainguinal bypass (prosthetic grafts, seven patients; prosthetic-vein composite grafts, two; venous grafts, five; and ileofemoral stent-graft, one). Cutting balloon PTA was followed by conventional PTA to improve anastomotic diameter. Patients with stenotic vein grafts underwent cutting balloon PTA after failed conventional PTA; the other patients were treated primarily with cutting balloon PTA. Criteria for success were a lumen diameter improvement of greater than 50% or residual stenosis of 20% or less. Follow-up was performed with color duplex ultrasonographic surveillance. Patency rates and durations were calculated with Kaplan-Meier survival curves and log-rank statistics. RESULTS: Attempted conventional PTA (n = 6) prior to cutting balloon PTA was unsuccessful. Cutting balloon PTA was technically successful in 15 (94%) of 16 lesions, without clinical complications. Two local restenoses and one graft occlusion occurred between 5 and 7 months. The cumulative 6-month primary and secondary graft patency rates were 84% and 92%, respectively. At 12 and 18 months, they were 67% (95% CI: 0.34, 0.86) and 83% (95% CI: 0.48, 0.96), respectively; mean follow-up was 10.0 months. CONCLUSION: Cutting balloon PTA proved feasible for treatment of resistant peripheral arterial bypass graft stenosis, commonly caused by neointimal hyperplasia, with excellent technical success. Short-term patency with this technique appears to be superior to that with conventional PTA, and it compares well with patency of atherectomy for salvage of infrainguinal bypass grafts.     

Percutaneous transluminal angioplasty for intracranial arteriosclerotic lesions

We report 17 cases of intracranial arterial stenosis treated by percutaneous transluminal angioplasty (PTA), including 9 on the intracranial internal carotid (ICA), 4 on the middle cerebral (MCA), and 4 on vertebrobasilar artery (VBA) system. All patients had ischaemic brain symptoms and stenoses of more than 60 % (calculated angiographically). We treated four patients by PTA for residual stenoses after thrombolysis for acute occlusion. We used PTA balloon catheters 2.0–3.5 mm in diameter for all procedures. As a rule, the balloon was inflated for 1 min at 6 atm. All arteries were successfully dilated (stenosis less than 50 %) except for one treated by PTA for residual MCA stenosis after thrombolysis. The patient died of a massive infarct due to MCA reocclusion caused by arterial dissection. Stenosis recurred in 4 of 16 patients. Repeat PTA was successfully carried out in these cases. However, stenosis recurred in one of these patients 3 months after PTA, but the patient is being followed because he is asymptomatic. PTA of intracranial arteries is effective, but its indications should be based strictly on potential risks, such as acute occlusion derived from arterial dissection. Received: 8 September 1997 Accepted: 6 January 1998     

Modified use of the arrow-trerotola percutaneous thrombolytic device for the treatment of thrombosed hemodialysis access grafts.

PURPOSE: To assess the safety and efficacy of using the Arrow-Trerotola percutaneous thrombolytic device (PTD) as the sole means of mechanical thrombolysis in hemodialysis access grafts, including in situ treatment of the arterial plug. PATIENTS AND METHODS: Fifty consecutive patients (22 women, 28 men; mean age, 58 years; mean graft age, 29 months), in whom mechanical thrombolysis of a thrombosed hemodialysis access graft using the PTD was planned, were included in the study. In all patients, the PTD was used to treat the arterial plug in situ at the arterial anastomosis, instead of using a Fogarty catheter to reposition the plug, as indicated in the PTD product labeling. Prospective data collection included demographic information, technical details of the procedure, immediate outcomes, and complications. Patients were followed for 3 months using definitions and data forms that were identical to those used in the original clinical trial of the PTD. A sample of procedures drawn from the PTD clinical trial database (n = 54) served as control. RESULTS: Immediate technical patency was 100%. Complications included arterial embolization (6% versus 2% control; P = NS; all successfully treated with backbleeding); venous rupture (6% versus 2% control; P = NS); and sepsis (n = 1), probably due to occult graft infection. Adjunctive therapy with an Adherent Clot catheter was needed in two procedures (4%). Three month patency using life-table analysis was 42% (versus 39% control; P = NS). The number of subsequent interventions (surgical/percutaneous) to the arterial limb of the graft did not differ from the PTD trial, and no native arterial stenoses were detected during the follow-up period. CONCLUSIONS: The PTD is safe and effective when used as the sole means of mechanical thrombolysis of hemodialysis grafts. Treating the arterial plug in situ with the PTD eliminates the need for a Fogarty or Adherent Clot catheter in 96% of procedures. A slight increase in arterial embolic complications was observed but these were easily treated with backbleeding.     

Ultrahigh-pressure versus High-pressure Angioplasty for Treatment of Venous Anastomotic Stenosis in Hemodialysis Grafts: Is There a Difference in Patency?

PURPOSE: Ultrahigh-pressure (UHP) balloon catheters were compared with high-pressure (HP) balloon catheters to determine if there was a difference in patency after percutaneous transluminal angioplasty (PTA) of venous anastomotic stenoses. MATERIALS AND METHODS: A retrospective study was conducted from January 2001 to September 2005 that included 22 patients with synthetic hemodialysis grafts who underwent 110 PTA procedures for venous anastomotic stenoses. Data collected included graft configuration and location, percent stenosis, balloon type used, residual stenosis, and total access blood flow before and after intervention. Patency from time of initial PTA to the next intervention was estimated with the Kaplan-Meier technique, with initial failures included in the analysis. RESULTS: A total of 55 PTAs were performed in each group. Technical success rate was 96% (n = 106) and clinical success rate was 100%. Median survival times were 4.6 months for the UHP cohort and 5.4 months for the HP group. When each event was considered independent, the difference was significant (P = .014). However, when each PTA event was considered dependent on earlier PTA events, no significant difference in patency was observed (P = .64). The mean increases in access blood flow rate by ultrasound dilution (available for 71 events) after PTA were 264 mL/min with UHP and 524 mL/min with HP (P = .14, Student t test). One minor complication (0.9%) of focal extravasation after PTA occurred and resolved with prolonged balloon inflation. CONCLUSION: Routine use of UHP for PTA of venous anastomotic stenoses in synthetic hemodialysis grafts was not associated with any significant change in patency compared with routine HP balloon angioplasty.     

Successful intra-arterial alteplase infusion is a predictor of 12-month limb survival in patients with lower limb arterial occlusion

AIM: To determine the factors predicting amputation of the affected lower limb 12 months after thrombolysis for acute arterial occlusion. MATERIALS AND METHODS: The clinical endpoints of 39 patients (24 men, 15 women; average age 69 years) 1 year after catheter-directed thrombolysis with alteplase (mean dose 30 mg, mean duration 24h) for lower limb arterial occlusion (30 native arteries, nine grafts) from January 2001 to June 2005 were assessed. The amputation rate at 12 months was analysed in relation to the thrombolytic outcome, type of vessel occluded, presence or absence of complications, and subsequent requirement for additional surgery on an elective basis using Fischer's exact test. RESULTS: Successful thrombolysis, defined as complete clot dissolution based on angiographic imaging, was achieved in 64.1% of cases (19 native artery, six bypass graft) with a total complication rate of 23% (n=9). The incidence of major haemorrhage was 7.5% (n=3, hypotension and haematemesis, groin haematoma and hypotension, haematemesis). No patient had an intracranial bleed. One year after thrombolysis, 28.2% (n=11) had further surgery (bypass graft, fasciotomy, embolectomy) and the amputation rate was 20.5% (n=8). Statistical analysis showed that the amputation rate was significantly higher for patients with failed compared with successful thrombolysis (p=0.02). The amputation rates did not reach statistical significance in relation to native artery or graft occlusion, presence or absence of complications, and whether or not additional surgery was required. CONCLUSION: Successful thrombolysis was a predictor for limb survival up to 12 months post-thrombolysis regardless of the type of vessel occlusion, presence of complications or additional surgical requirement.     

Placement of venous stents: clinical experience with a self-expanding prosthesis.

A self-expanding vascular prosthesis was used to treat 20 venous stenoses or occlusions in 13 patients. The lesions were caused by tumor (n = 5), postoperative fibrous scars (n = 2), and chronic hemodialysis fistulas (n = 13). Follow-up ranged between 6 weeks and 53 months (mean follow-up, 14.9 months). Acute occlusion occurred in two stents, one within a tumor stenosis and one in a dialysis shunt after 3 days and 2 days, respectively. Balloon angioplasty, thrombolysis, and aspiration in the first case and balloon angioplasty and thrombolysis in the second case successfully restored patency. Definite occlusion occurred in these two patients after 8 weeks and 5 months, respectively. Ten secondary interventions were performed in three patients with 10 restenoses who had stenotic arm veins in chronic hemodialysis at presentation. Five of seven patients who received treatment for stenoses associated with hemodialysis underwent successful kidney transplantation 5-27 months after placement of vascular stents. Both patients who received treatment for benign strictures had patent stents at follow-up examinations performed at 45 and 53 months, respectively. Four of five stents placed for malignant stenoses were patent at venography (n = 3) or autopsy (n = 1).     

Tenecteplase in the Treatment of Thrombosed Hemodialysis Grafts

A pilot study was carried out to prospectively evaluate the efficacy and safety of Tenecteplase (TNKase) using a modified ’lyse and wait” technique with percutaneous transluminal angioplasty (PTA) to treat thrombosed hemodialysis arteriovenous grafts (AVG)s. Seven patients with eight hemodialysis AVGs were treated and followed up to 1 year. Dosing included 1 mg TNKase and 3,000–4,000 U of heparin. Technical and clinical success rates were 100% and 88%, respectively. No major complications occurred. Primary patency rates at 30, 90, and 180 days were 62%, 50%, and 33%, respectively. TNKase, used in this fashion, may be comparable to alteplase and reteplase for safe and effective thrombolysis of PTFE dialysis grafts.     

Reteplase in the treatment of thrombosed hemodialysis grafts.

PURPOSE: To prospectively evaluate the efficacy and safety of reteplase with percutaneous transluminal angioplasty (PTA) in the treatment of thrombosed polytetrafluoroethylene hemodialysis arteriovenous grafts (AVGs). MATERIALS AND METHODS: Forty-two patients were entered into the study. Sixty-two procedures in 43 grafts were performed. One unit of reteplase and 4,000 units of heparin were administered into the AVGs. Routine venography and percutaneous transluminal angioplasty (PTA) was then performed. Patients were transferred for hemodialysis immediately after the procedure. RESULTS: Technical success was achieved in 92% of the cases. Four cases involved intentional repeat thrombosis because of poor outflow and/or need for a new graft site. Minor complications occurred in 6.5% of the cases. No major complications occurred. The mean procedure time for experienced versus less-experienced interventionalists was significantly shorter (P <.001). Primary patency rates were 50%, 34%, and 34% at 30, 90, and 180 days, respectively. CONCLUSION: Reteplase in conjunction with heparin and PTA is a safe and effective means of thrombolysis of AVGs. Its efficacy is comparable to that of other available thrombolytic drugs.     

血液透析动静脉内瘘血管狭窄和闭塞的介入治疗

目的探讨经导管溶栓、经皮血管成形术(PTA)治疗血液透析动静脉内瘘狭窄和闭塞的可行性和有效性。方法对25例自体血管血液透析动静脉瘘道狭窄和闭塞患者行血管造影,18例血栓形成闭塞患者经导管尿激酶溶栓治疗,16例血管狭窄行PTA。结果 25例造影显示血栓闭塞18例,单纯性狭窄7例;经溶栓治疗开通16例,即时开通率88.9%(16/18)。溶栓开通16例中9例显示血管狭窄,该9例与单纯性狭窄7例共16例进行了PTA治疗,成功14例,失败2例,术后所有病例未发生肺梗塞、出血等并发症。溶栓完全开通或PTA成功后,即感血管震颤较前明显增强,次日透析时血流量达到250mL/min,可完全满足透析需要。结论经导管溶栓和PTA是治疗动静脉内瘘血栓形成和血管狭窄的安全、有效和微创的方法,经导管溶栓具有较高的开通率;对栓塞伴有血管狭窄的患者,在溶栓的基础上,结合PTA可提高远期开通率。     

Angioplasty of Long Venous Stenoses in Hemodialysis Access: At Last an Indication for Cutting Balloon?

PURPOSE: To compare the postintervention primary patency rates of cutting balloon angioplasty (CBA) with those of conventional percutaneous transluminal angioplasty (PTA) in the treatment of hemodialysis-related stenoses at least 2 cm long. MATERIALS AND METHODS: This retrospective and controlled study included 29 patients with a hemodialysis-related stenosis at least 2 cm long. From August 2002 to August 2003, nine patients (PTA group, six upper-arm and three forearm fistulas) were treated with a conventional balloon (5-8 mm, 4 cm long). From September 2003 to December 2005, 20 patients (CBA group, 12 upper-arm and seven forearm fistulas; one polytetrafluoroethylene hemodialysis graft) were treated with a cutting balloon (5-7 mm, 1 cm long). The median follow-up was 22.1 months for the CBA group and 15.6 months for the PTA group. The Kaplan-Meier method was used to calculate the primary cumulative patency rates, and the log-rank test was used for comparison. Multivariate Cox models were generated by combining three variables: patient age, stenosis length, and treatment type (CBA or PTA). RESULTS: In the CBA group, the postintervention primary patency was 85% +/- 16 at 6 months, 70% +/- 20 at 1 year, and 32% +/- 26 at 18 months. In the PTA group, the postintervention primary patency was 56% +/- 32 at 6 months and 21% (range, 0%-53%) at 1 year. When comparing PTA versus CBA with the log-rank test, there was a statistically significant difference (P = .009). With the multivariate Cox models, treatment was again a statistically significant (P = .007) determinant of primary patency; patient age and stenosis length were not. CONCLUSION: The use of a cutting balloon as the first-line treatment for stenoses at least 2 cm long significantly improves the postintervention primary patency rate.     

PTA versus Stent in der femoropoplitealen Strombahn

PURPOSE: To evaluate whether primary stenting is superior to balloon angioplasty (PTA) alone in the treatment of femoropopliteal obstructive disease. MATERIALS AND METHODS: Sixty-two patients, 24 female and 38 male, mean age 67 years (39-87) years, were randomized to PTA alone (n = 37) or balloon angioplasty followed by implantation of Palmaz stents (n = 33). Follow-up included clinical assessment, ankle-brachial index (ABI), color duplex ultrasound at 1, 3, 6 and 12 months after intervention and intravenous angiography at 6 or 12 months. RESULTS: We had four cases of primary PTA failures (10.8%) and no early (< 30 days) thrombosis compared to one primary stent failure (3.0%) and three early thromboses (9.0%) in the stent group. Cumulative primary angiographic patency rates (life-table analysis) for PTA alone were 82% and 72% (6 and 12 months, respectively) compared to 81% and 60% for primary stent placement. The secondary angiographic patency were 97% and 88% for PTA and 88% and 72% for stent implantation, respectively. However, there was no significant difference in patency rates. CONCLUSIONS: Despite fewer primary technical failures, mid-term angiographic and clinical patency were not improved by primary stent placement compared to PTA alone.     

Combined direct percutaneous transluminal angioplasty and low-dose native tissue plasminogen activator therapy for acute embolic middle cerebral artery trunk occlusion

BACKGROUND AND PURPOSE: In embolic middle cerebral artery (MCA) trunk occlusion, recanalization with direct percutaneous transluminal angioplasty (PTA) may be preferable to time-consuming thrombolysis. However, distal embolization with small crushed fragments is a complication of direct PTA. We prospectively evaluated combined direct PTA and low-dose native tissue plasminogen activator (t-PA) therapy for acute embolic MCA trunk occlusion. METHODS: Fifteen patients underwent direct PTA. The embolus was successfully crushed in 12, who received subsequent native t-PA infusion. Direct PTA was performed with a balloon catheter, which was advanced into the occlusion site and inflated several times until recanalization was established. After PTA, 7.2 mg of native t-PA in 100 mL of isotonic sodium chloride solution was infused for 30 minutes. Neurologic status was evaluated at admission and immediately and 1 month after treatment. In all patients, follow-up CT was performed within 24 hours and 3-7 days after onset, and follow-up MR imaging, 1 month after onset. RESULTS: Direct PTA failed to crush the embolus in three of 15 patients; these three had no clinical improvement. In 11 of 12 patients, combined therapy was successful, with no technical complication. Although no symptomatic intracerebral hemorrhage occurred, one patient had a small hematoma. All patients with successful recanalization had marked clinical improvement. Although angiograms showed distal embolizations in 10, cortical infarctions were confirmed in only three at follow-up. CONCLUSION: Combined direct PTA and IV low-dose native t-PA therapy may be a safe alternative to thrombolytic therapy in some patients with embolic MCA trunk occlusion.     

Retrospective comparison of the Amplatz thrombectomy device with modified pulse-spray pharmacomechanical thrombolysis in the treatment of thrombosed hemodialysis access grafts.

PURPOSE: To retrospectively evaluate the Amplatz thrombectomy device (ATD) in the treatment of thrombosed hemodialysis grafts and compare it with modified pulse-spray pharmacomechanical thrombolysis (PPT). MATERIALS AND METHODS: During a 4-month period, 79 patients presented with 126 episodes of graft occlusion. Percutaneous recanalization was performed by using the ATD (n = 57) or the modified PPT technique (n = 69). Evaluation included the technical success, complications, and primary patency rates. RESULTS: Technical success was achieved in 93% (53 to 57) of the cases treated with the ATD and in 96% (66 of 69) of the cases treated with modified PPT (P = .70). Complications occurred in 6% (four of 69) of modified PPT procedures and 16% (nine of 57) of ATD procedures. This difference was not statistically significant (P = .08); however, there were significantly more local complications in the ATD group (P = .04). The primary patency rates at 30, 90, and 180 days were 65% and 65%, 36% and 50%, and 26% and 33% for modified PPT and ATD, respectively. Survival curves were found not to differ significantly (P = .49). CONCLUSION: The ATD and modified PPT were similarly successful in the recanalization of thrombosed hemodialysis access grafts and achieved comparable primary patency rates. The higher rate of local complications and technical difficulties encountered with use of the 8-F ATD limit its usefulness for this indication.     

Hydrodynamic thrombectomy system versus pulse-spray thrombolysis for thrombosed hemodialysis grafts: a multicenter prospective randomized comparison

P:URPOSE: To evaluate the safety and efficacy of a hydrodynamic thrombectomy system in a prospective, multicenter randomized comparison with pulse-spray thrombolysis in hemodialysis grafts. MATERIALS AND METHODS: Nine centers enrolled 120 adult patients with recently (相似文献   

Prospective study of balloon inflation pressures and other technical aspects of hemodialysis access angioplasty

PURPOSE: Balloon angioplasty is a mainstay in the treatment of failing or thrombosed hemodialysis access grafts and fistulas. A sizable body of outcomes data exists concerning percutaneous transluminal angioplasty (PTA) in hemodialysis access, yet there is a relative paucity of technical information available, especially regarding dilation pressures. The aim of the present study was to compile such information, which can be critical to the choice of devices for PTA and to the design of future clinical trials seeking to improve outcomes in this area. MATERIALS AND METHODS: Technical data were collected prospectively for 102 PTA procedures (66 prophylactic PTA procedures and 36 PTA procedures performed during access thrombectomy). Demographic data concerning the access were collected. Technical data were collected individually for each lesion treated, including lesion location; degree of stenosis (in quartiles); lesion length; PTA balloon brand, size, and length; pressure at which the waist of the balloon was effaced; residual stenosis; and reason for additional balloons or inflations if used. Outcomes data other than residual stenosis were not collected, but the endpoint for all interventions was a thrill in the access. RESULTS: A total of 230 lesions were treated. Two (1%) could not be successfully treated with PTA despite the use of "ultra high" pressure (approximately 40 atm); one was treated successfully with parallel wire technique and the other was revised surgically after the use of a cutting balloon also failed. Overall, 55% of lesions required pressures greater than 15 atm to efface the waist. Excluding initial failures, 20% of lesions in native fistulas and 9% in grafts required very high pressure (>20 atm) to efface the waist (P = .02). High pressure was needed less frequently in PTA procedures performed in the setting of thrombectomy procedures than in prophylactic PTA procedures (P = .0001). Residual stenosis was positively correlated with severity of initial stenosis and negatively correlated with duration of inflation. CONCLUSIONS: Conventional angioplasty balloons are inadequate for the treatment of most hemodialysis access stenoses. High pressures (>15 atm) are commonly needed for PTA in hemodialysis access. Very high pressures (>20 atm) are more frequently needed in native fistulas.     

Long-term follow-up of management of failing in situ saphenous vein bypass grafts using endovascular intervention techniques

PURPOSE: To report the long-term follow-up of previously reported cases of salvaging failing or failed in situ bypass grafts using endovascular techniques, to include previously unreported cases, and to include the results of thrombolysis for the salvage of occluded in situ venous bypass grafts. MATERIALS AND METHODS: Between 1985 and 1995, 352 patients underwent distal bypass via the in situ saphenous vein. Seventy-three of these patients underwent endovascular interventions for (i) graft stenoses (65 lesions in 40 patients) treated by balloon angioplasty (PTA), (ii) AV residual fistulas to veins (AVF) (23 patients) occluded by coil embolotherapy, (iii) graft occlusion (21 occluded grafts in 19 patients) treated by catheter-directed high-dose thrombolytic infusion and PTA or surgical revision of uncovered stenoses, and (iv) retained valve leaflets causing stenoses (five patients) treated by valvectomy and/or PTA. Cumulative patency rates were determined by the Kaplan-Meier method. Twenty-nine of 73 patients had been previously reported by the authors. RESULTS: PTA was successful in 39 of 40 patients, cumulative patency after bypass PTA was 0.79 (SE +/- 0.07) for 12 months and 0.63 (SE +/- 0.12) for 5 years. The only complication of PTA was a graft anastomotic disruption that was successfully treated by surgery. Longer lesions and lesions requiring repeated PTA were more likely to restenose. For thrombolysis, there were 13 of 19 successful infusions and five delayed occlusions. The cumulative patency for both 12 months and 5 years was 0.43 (SE +/- 0.12). AVF embolization was successful in 21 of 23 patients. Cumulative patency for 12 months and 5 years was 0.87 (SE +/- 0.07) and 0.81 (SE +/- 0.09), respectively. Five successful valvectomy procedures were performed by stripping residual valves with endocardial forceps. CONCLUSION: In experienced hands, PTA and AVF embolization can be performed on failing in situ saphenous vein bypass grafts with good long-term patency. Thrombolysis results were less favorable but can prolong patency of grafts.     

Selective venous thrombolysis with the nipple-balloon catheter: comparative evaluation in vivo.

PURPOSE: To compare in an animal model of deep vein thrombosis, an intramural drug delivery catheter, the nipple-balloon catheter, with an occlusion balloon-infusion guide wire system. MATERIALS AND METHODS: Ten juvenile pigs were used for the study. Deep vein thrombosis was induced in both hind limbs by using a previously described technique. Heparin was administered 30 minutes later (2,500 IU intravenously) and bilateral thrombolysis was attempted with use of 8 mg of alteplase as a 0.25 mg/mL solution containing heparin 50 IU/mL (n = 10) and sodium/meglumine ioxaglate 40 mgI2/mL (n = 5). In one limb, the external iliac vein was endoluminally occluded, and 0.8 mL of alteplase was administered every 3 minutes through a multisideport infusion wire placed coaxially through the balloon catheter. On the other side, a nipple-balloon catheter was used: alteplase was injected as two 0.4-mL aliquots every 3 minutes in overlapping segments of the vessel. Blood samples were taken at predetermined intervals to determine the partial thromboplastin time and plasma fibrinogen concentration. At autopsy, the thrombus mass in the iliofemoral veins was measured, and the extent of residual thrombosis in the venous tributaries was graded at four sites. The heart and the lungs were also examined for thromboemboli (n = 5). Venous specimens were then subjected to X-ray fluorescence spectrometry to determine iodine content (n = 5). RESULTS: Bilateral thrombolysis could be successfully completed in all animals. No procedural problem associated with the use of the nipple-balloon catheter was encountered. The mass of residual thrombus in the axial veins was significantly lower in this group (P = .005). The drug delivery system used did not appreciably influence thrombolysis in the tributaries. Signs of macroscopic damage to the veins were not observed in any animal. None of the venous specimens had detectable levels of iodine. Small thromboemboli were found in the pulmonary circulation in three of five animals. Fibrinogen levels did not decrease during the procedure. CONCLUSIONS: The significantly lower residual thrombus burden associated with use of the nipple-balloon catheter suggests that the device may have the potential to be an effective delivery system for selective thrombolysis in veins.