球囊扩张联合覆膜支架植入治疗人造血管动静脉内瘘狭窄

目的 探讨球囊扩张联合覆膜支架植入治疗人造血管动静脉内瘘(AVG)狭窄的临床疗效.方法 前瞻性选取15例经皮腔内血管成型术(PTA)疗效欠佳的AVG狭窄患者,且具备以下特点:狭窄长度不超过7 cm,狭窄程度大于50％;PTA后3个月内狭窄复发2次或以上;扩张后残余狭窄＞30％或狭窄部位立即弹性回缩.所有患者在数字减影血管造影(DSA)下行球囊扩张后植入不同内径的聚四氟乙烯覆膜支架.结果 男3例,女12例,平均年龄(66±12)岁.支架植入前内瘘平均使用时间为(19.5±15.0)个月.共植入支架16枚,技术成功率100％,植入部位为静脉吻合口9例(9/15);静脉流出道6例(6/15),其中头静脉3例,肱静脉2例,腋静脉1例.首次开通率3个月为40％,6个月为19％,12个月为13％.再次开通率3个月为93％,6个月为88％,12个月为87％.术后平均随访时间为(14.9±5.3)个月,再窄狭率为87％(13/15).术后PTA 36例次,支架内狭窄36％ (13/36);支架远端狭窄8％ (3/36);支架近端狭窄22％(8/36);与支架无关的狭窄33％ (12/36).AVG中位生存时间为25个月.结论 球囊扩张联合覆膜支架植入治疗AVG狭窄技术成功率高,并发症少,首次开通率不高,但再次开通率令人满意.     

球囊扩张成形术处理透析用动静脉内瘘狭窄性病变及短中期结果

目的:探讨球囊扩张成形技术在治疗血液透析用动静脉内瘘(AVF)狭窄的临床效果。方法:回顾性分析2014年5月—2015年12月间采用球囊扩张成形技术治疗的31例血液透析用AVF狭窄性病变患者的临床资料。结果:31例患者中,男18例,女13例;桡动脉-头静脉内瘘27例,桡动脉-贵要静脉内瘘2例,尺动脉-贵要静脉内瘘2例;均接受球囊扩张技术治疗。28例(90.3%)获得技术上的成功,围手术期无患者死亡。1例患者术后出现动脉穿刺处假性动脉瘤,1例患者术后出现AVF血栓形成,1例患者出现前臂皮下血肿,其他所有患者AVF恢复通畅并能够以正常流量进行血液透析治疗。术后随访3~12个月,3、6、12个月初次通畅率分别为92.9%,75.0%,50.0%。结论:球囊扩张成形术处理AVF狭窄性病变微创、安全,是AVF狭窄性病变的合理治疗方法,但其中长期疗效仍有待于进一步改善。     

Ultrasound evaluation and interventional therapy for peripheral vascular access stenosis in dialysis patients

Objective To investigate the patency rate and restenosis after percutaneous transluminal angioplasty (PTA) for the treatment of arteriovenous fistula (AVF) and arteriovenous graft (AVG) stenosis in dialysis patients. Methods The patients who were successfully treated by PTA for the first time in the blood purification center of the 2nd Affiliated Hospital of Nanjing Medical University from January 2016 to June 2017, including 71 cases of AVF in the forearm, 52 cases of AVF in the upper arm and 59 cases of AVG were recorded. The data of different stenosis parts were analyzed before and after treatment and followed up for 12 months. The initial patency rate and assisted-PTA patency rate were observed at 3 months, 6 months, 9 months, and 12 months after ultrasound interventional therapy, and the initial patency time for patients who needed to reintervention among all types of pathways were recorded. Results The initial patency rates at 3 months, 6 months, 9 months and 12 months after ultrasound interventional therapy were 98.59%, 90.14%, 71.93%, 54.93% respectively in forearm AVF, 90.38%, 65.38%, 42.31%, 32.69% respectively in upper arm AVF, 91.53%, 32.20%, 6.78%, 1.69% respectively in AVG, and the PTA-assisted patency rates were 98.59%, 97.18%, 95.77%, 94.37% respectively in forearm AVF, 92.31%, 86.54%, 84.62%, 80.77% respectively in upper arm AVF, 100.00%, 98.31%, 96.61%, 93.22% respectively in AVG, while the initial patency time was (8.99±3.54) months in forearm AVF, (6.33±3.01) months in upper arm AVF, (4.80±1.40) months in AVG respectively. Conclusions Ultrasound can comprehensively evaluate the function of peripheral vascular access, guide PTA treatment, and evaluate treatment outcomes. Ultrasound intervention therapy has best initial patency rate for forearm AVF stenosis. The prognosis of upper arm AVF stenosis PTA is relatively poor due to the easy cephalic stenosis. Although AVG has a short interval of restenosis, it can achieve a better long-term patency rate through regular intervention with ultrasound intervention.     

A systematic review and meta-analysis of plain versus drug-eluting balloon angioplasty in the treatment of juxta-anastomotic hemodialysis arteriovenous fistula stenosis

ObjectiveOwing to the lack of comparative evidence between the endovascular technologies for arteriovenous fistula (AVF) stenosis treatments, we sought to summarize the reported data comparing the effectiveness of different endovascular approaches for the treatment of AVF stenoses at the juxta-anastomotic site.MethodsWe performed a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases were searched from inception to June 12, 2018 for observational and randomized studies that had examined the effectiveness of AVF stenosis treatment using plain percutaneous balloon angioplasty (PTA), cutting balloon angioplasty, drug-eluting balloon (DEB) angioplasty, high-pressure balloon angioplasty, and stenting. Bias was assessed using the Newcastle-Ottawa scale for observational studies and the Cochrane Collaboration tool for randomized studies. Article screening, full-text review, assessment of bias, and data collection were conducted in duplicate, with a third reviewer to reconcile any discrepancies. We conducted a qualitative synthesis of the available evidence and a quantitative meta-analysis for the primary assisted patency outcome. The meta-analysis was conducted using Review Manager, version 5.3, using random effects models, with the I² statistic used to assess heterogeneity. Statistical significance was set at P < .05.ResultsOur search yielded 3683 reports. Of these, three randomized trials and three observational studies were included. Three studies with 342 patients had described the effectiveness of high-pressure balloon angioplasty, conventional PTA, and stenting and had analyzed the data qualitatively. Three studies with 141 patients had investigated native AVF patency after DEB angioplasty and conventional PTA and were included in the meta-analysis. DEB angioplasty showed significantly greater primary assisted patency rates at 12 months after treatment compared with PTA (odds ratio, 3.66; 95% confidence interval, 1.32-10.14; I² = 49%). No statistically significant differences were found in 6-month primary assisted patency among the treatment groups (odds ratio, 2.03; 95% confidence interval, 0.64-6.45; I² = 50%). A total of 58 of 72 AVFs remained patent 6 months after DEB angioplasty compared with 45 of 69 at 6 months after PTA. At 12 months after treatment, 48 of 72 AVFs remained patent after DEB angioplasty compared with 23 of 69 AVFs after PTA.ConclusionsOur findings suggest DEB angioplasty is a more effective treatment option for AVF stenosis at the juxta-anastomotic site compared with PTA. Although DEB angioplasty might provide longer term patency than other endovascular treatments, further high-quality data are needed to confirm this finding.     

超声引导下腔内血管成形术治疗动静脉内瘘狭窄早期疗效评估

目的探讨超声引导下腔内血管成形术在治疗血液透析动静脉内瘘(AVF)狭窄的早期疗效。方法回顾性分析接受超声引导下经皮腔内血管成形术(PTA)治疗的24例前臂AVF狭窄的透析患者的临床资料,比较术前及术后即刻狭窄处内径,对通畅率采用Kaplan-Meier生存分析。结果 24例患者均获得技术成功,成功率为100%(24/24)。无穿刺部位假性动脉瘤及皮下血肿等并发症发生,除1例术后AVF血栓形成,围术期无患者死亡。术后随访3、6、9、12个月的初级通畅率分别为87.50%(21/24)、83.33%(20/24)、79.17%(19/24)、58.33%(14/24)。结论超声引导下PTA治疗AVF狭窄性病变微创、安全,是AVF狭窄性病变的合理治疗方法,近期效果明显。     

Short- and long-term functional effects of percutaneous transluminal angioplasty in hemodialysis vascular access

The efficacy of percutaneous transluminal angioplasty (PTA) is usually expressed as the angiographic result. Access flow (Qa) measurements offer a means to quantify the functional effects. This study was performed to evaluate the short-term functional and angiographic effects of PTA and to determine the longevity of the functional effects during the follow-up period. Patients with an arteriovenous graft (AVG) or an arteriovenous fistula (AVF) who were eligible for PTA (Qa values of <600 ml/min) were included. Ultrasound-dilution Qa measurements were obtained shortly before PTA and periodically after PTA, beginning 1 wk after the procedure. The short-term effects were expressed as the increase in Qa and the reduction of stenosis. The long-term effects were expressed as patency and the decrease in Qa after PTA. Ninety-eight PTA procedures for 60 patients (65 AVG and 33 AVF) were analyzed. Qa improved from 371 +/- 17 to 674 +/- 30 ml/min for AVG and from 304 +/- 24 to 638 +/- 51 ml/min for AVF (both P < 0.0001). In 66% (AVG) and 50% (AVF) of cases, Qa increased to levels of >600 ml/min. The degree of stenosis decreased from 65 +/- 3 to 17 +/- 2% for AVG and from 72 +/- 5 to 23 +/- 7% for AVF (both P < 0.005). The reduction of stenosis was not correlated with DeltaQa (r(2) = 0.066). Six-month unassisted patency rates after PTA were 25% for AVG and 50% for AVF. The decreases in Qa were 3.7 +/- 0.8 ml/min per d for AVG and 1.8 +/- 0.9 ml/min per d for AVF. Qa values before PTA and DeltaQa were correlated with the subsequent decrease in Qa (P < 0.005). In conclusion, Qa increases after PTA but, in a substantial percentage of cases, not to levels of >600 ml/min. Qa values before PTA and the increase in Qa were correlated with long-term outcomes, whereas angiographic results were not. These data, combined with literature data, suggest that there is optimal timing for PTA.     

Cutting balloon angioplasty for resistant venous anastomotic stenoses

Conventional angioplasty of stenoses at the venous anastomosis has been demonstrated to be an important endovascular adjunct to mechanical thrombectomy of clotted arteriovenous dialysis grafts. In some cases, however, severe venous anastomosis stenosis is resistant to angioplasty. Cutting balloon angioplasty may have an advantageous role in these difficult situations in order to avoid surgical revision. In this series of 350 patients receiving percutaneous, endovascular declotting procedures, 9 patients had high-grade venous anastomotic stenoses (opening less than 2 mm) that could not be remedied with either conventional or high-pressure noncompliant peripheral angioplasty balloons. These nine patients had the lesions opened with the use of 4 mm x 10 mm cutting balloons and placement of self-expanding nitinol stents at the venous anastomosis during the same angiography procedure. Patients were followed for patency and functionality of the graft. In all cases, immediate technical success occurred. Among these patients, the vessels have remained patent for as long as 20 months of follow-up and grafts have remained functional. Cutting balloon angioplasty may have a potential therapeutic role in resistant venous anastomotic stenoses.     

介入手术联合口服培哚普利治疗血液透析患者动静脉瘘功能不良的疗效

目的 探讨经皮血管成形术(percutaneous transluminal angioplasty,PTA)治疗血液透析动静脉内瘘狭窄的有效性,比较介入手术后联合培哚普利对再次狭窄率的影响.方法 对17例自体血管动静脉内瘘狭窄患者行血管造影,其中15例行PTA.7例患者PTA术后每日口服培哚普利8 mg,7例患者未服用任何血管紧张素转换酶抑制剂(angiotensin converting enzyme inhibitor,ACEI)和血管紧张素Ⅱ受体拮抗剂(angiotensin receptor blocker,ARB).术后对患者进行随访,观察球囊扩张术的并发症、技术成功率、临床成功率和半年通畅率.结果 17例患者均在动静脉内瘘成熟并使用3个月以上发生功能不良,造影见狭窄多位于动静脉吻合口附近及头静脉透析用穿刺段.经PTA治疗后,造影显示狭窄段血管扩张、再通,治疗技术成功率达86.7％ (13/15),临床成功率达93.3％(14/15).2例患者因为导丝无法通过近乎闭塞段血管而选择其他手术方式.穿刺部位血肿2例,无医源性血管破裂,无继发血栓形成.随访6个月,14例获得临床成功的患者内瘘半年通畅率为64.3％,其中培哚普利组发生再次狭窄1例,对照组发生再次狭窄4例.结论 PTA是治疗动静脉内瘘狭窄安全、有效及微创的方法,联合口服培哚普利可能有助于降低术后再次狭窄率.     

Paclitaxel drug-coated balloon angioplasty for the treatment of failing arteriovenous fistulas: a single-center experience

Abstract

Objectives: To report our experience of angioplasty with Lutonix (Bard Peripheral Vascular, Inc., Tempe, AZ) drug-coated balloon (DCB) for the treatment of failing arteriovenous fistulas (AVF).

Materials and methods: Retrospective, single-center analysis consisting of 14 patients treated with Lutonix paclitaxel DCBs in the period from July 2015 through April 2017. We analyzed technical success, clinical success, primary patency of the target lesion, primary patency of the dialysis circuit, and the rate of complications. Regular follow-up of AVF patency was realized by clinical examination and duplex ultrasonography. The Kaplan–Meier survival method was applied to determine the cumulative primary patency of the target lesion and the dialysis circuit.

Results: Technical success was 100% and clinical success 92.9%. There were no major or minor complications. Cumulative target lesion primary patency after DCB was 69.2% at 6 months and 31.6% at 12 months. Cumulative vascular circuit primary patency was 61.5% at 6 months and 31.6% at 12 months.

Conclusion: Compared to results reported in literature with plain old balloon angioplasty (POBA), Lutonix paclitaxel DCB angioplasty proved a short-term patency benefit in treatment of dialysis AVF stenosis.     

Drug-coated balloon angioplasty for dialysis access fistula stenosis

Maintaining vascular access patency represents a tremendous challenge in hemodialysis patients. Although “native” arteriovenous fistula (AVF) is currently recommended as primary vascular access, neointimal hyperplasia stenoses frequently develop, with a risk for AVF thrombosis and vascular access loss. For years, first-line treatment of AVFs stenoses has been percutaneous transluminal angioplasty, generally with high-pressure or cutting uncoated balloons. However, restenosis and reintervention rates remain incredibly high and occur, according to recent studies, in up to 60% and 70% of patients at 6 and 12 months, respectively. Drug-coated balloons delivering paclitaxel at the angioplasty site have proved their superiority in the treatment of coronary and peripheral arterial stenoses. Paclitaxel reduces neointimal hyperplasia and drug-coated balloons, therefore, it represents an attractive option for AVF stenoses. Because data are scarce, the aim of this paper was to review the concepts and current results of drug-coated balloons in AVF stenosis management.     

Infrainguinal vein graft stenosis: cutting balloon angioplasty as the first-line treatment of choice

OBJECTIVE: The optimal treatment for hemodynamically significant infrainguinal vein bypass graft stenosis is not known. This study compares three options as first choice for the revision of failing infrainguinal vein grafts: cutting balloon angioplasty (CBA), standard percutaneous transluminal balloon angioplasty (PTA), and open surgical revision (OS). METHODS: Infrainguinal vein bypass graft lesions treated in a single institution during a 12-year period were evaluated. Of these, 161 lesions in 124 infrainguinal bypasses (101 patients) were treated with OS (n = 42), PTA (n = 57), or CBA (n = 62). The initial indication for the bypass in these patients was limb salvage in 73% and claudication in 27%. The primary outcome of interest was the development of vein graft occlusion or significant stenosis (>or=70%) as detected by surveillance duplex ultrasound scanning or arteriography some time after repair. RESULTS: The stenosis-free patency rates at 48 months for OS, CBA, and PTA were 74%, 62%, and 34%, respectively. PTA was associated with an increased risk of treatment failure compared with both OS (hazard ratio [HR], 3.9; P < .0001) and CBA (HR, 3.1; P < .0001). There was no significant difference between OS and CBA (HR, 1.3 for CBA vs OS, P = .6). Pseudoaneurysms developed in two CBA patients. One ruptured and required interposition graft, and one was monitored. CONCLUSION: Cutting balloon angioplasty is a reasonable, initial treatment for infrainguinal vein graft stenosis in most patients. It is a safe, minimally invasive, outpatient procedure with patency rates that are comparable to OS and superior to PTA.     

维持性血液透析患者前臂动静脉内瘘狭窄的球囊导管扩张治疗

目的：探讨球囊导管扩张（PTA）治疗维持性血液透析患者前臂动静脉内瘘（AVF）狭窄的临床效果。方法：自2006年01月～2010年06月,对5例前臂AVF的维持性血液透析患者进行了10次PTA治疗。结果：5例患者PTA术后即血流量恢复,但分别在3～24个月后复发,再次PTA治疗后血流量恢复;较短时间发生第1次复发的2例患者分别又在术后3、4个月发生第2次复发,其余患者目前尚未发生狭窄。结论：前臂AVF狭窄形成后,及时采用PTA治疗是修复失功能内瘘的一种行之有效的方法,PTA治疗后复发时间较长的患者,如发生再次复发可继续行PTA治疗。     

Cutting balloon angioplasty of autogenous infrainguinal bypasses: short-term safety and efficacy

PURPOSE: This study evaluated the safety and efficacy of cutting balloon angioplasty in the treatment of infrainguinal vein bypass graft stenosis. METHODS: Data from a prospective database, supplemented by chart review, were obtained on all patients who underwent cutting balloon angioplasty of lower extremity vein bypass grafts at a single institution during a 4-year period. Noninvasive duplex ultrasound imaging of grafts, along with measurement of ankle-brachial indices and digital pressures, was performed on all patients before and after treatment with the cutting balloon. Efficacy of cutting balloon angioplasty and procedural complications were analyzed. Data from noninvasive vascular testing were compared using the two-tailed paired Student t test. Patency rates were calculated using the Kaplan-Meier method. Differences in patency rates were compared using the log-rank test. RESULTS: From July 2002 to February 2006, 109 cutting balloon angioplasties were performed on 70 bypasses in 61 patients. There were 12 complications in 109 procedures (11%), only one of which required immediate operative intervention. Initial technical success was 96%. Noninvasive vascular testing indicators significantly improved immediately after intervention: peak systolic graft velocity decreased from 360 +/- 158 cm/s to 143 +/- 67 cm/s (P < .001), ankle-brachial index improved from 0.55 +/- 0.3 to 0.85 +/- 0.2 (P < .001), and digital pressure increased from 31 +/- 30 mm Hg to 62 +/- 32 mm Hg (P < .001). Patency rates at 6 months according to the Kaplan-Meier method were primary patency, 48% (95% confidence interval [CI], 0.36 to 0.60); assisted primary patency, 72% (95% CI, 0.61 to 0.83); and secondary patency, 99% (95% CI, 0.97 to 1.00). At 6 months, cumulative limb salvage was 94% (95% CI, 0.89 to 1.00). CONCLUSIONS: Cutting balloon angioplasty of infrainguinal vein bypass graft stenosis is technically feasible but is associated with a relatively high complication rate and a relatively low short-term patency rate.     

介入导管技术在动静脉内瘘失功治疗中的应用

目的:探讨动静脉内瘘(AVF)失功后介入手术的治疗方法,评估其治疗效果及应用价值。方法:回顾性分析自2006年4月—2015年1月行介入手术治疗的20例自体AVF失功患者的临床资料。结果:20例患者中,16例经静脉端造影,4例经股动脉-主动脉-腋动脉路径造影;单纯吻合口狭窄4例,行球囊扩张后狭窄明显改善;吻合口狭窄伴血栓形成有5例,切开取栓后再行球囊扩张治疗;静脉端血栓形成3例,切开取栓后返血良好;静脉端狭窄合并血栓形成7例,行切开取栓后再行球囊扩张治疗;头静脉长段闭塞1例,改用人工血管行AVF术。术后全部患者经该血管通路恢复透析治疗,透析时流量均200 m L/min。共17例患者获得随访,平均随访时间13.2个月,12个月通畅率为47.1%。结论:介入导管技术在治疗AVF失功方面是安全、有效的。     

Lysis/balloon angioplasty versus thrombectomy/ open patch angioplasty of failed femoropopliteal polytetrafluoroethylene bypass grafts

PURPOSE: Several studies have reported on the outcome of lysis/percutaneous transluminal balloon angioplasty (PTA) of failed or failing femoropopliteal bypass grafts (FPGs) with mixed results. None of these studies have compared the results of lysis/PTA versus thrombectomy/open patch repair for failed above-knee polytetrafluoroethylene (PTFE) FPGs. METHODS: Patients with failed (thrombosed) above-knee FPGs (PTFE, Goretex) during a 10-year period were given the option to choose between thrombectomy/open patch repair for localized anastomotic short stenosis (less-than-or-equal2 cm; group A, 31 patients) and lysis/PTA or thrombectomy/balloon angioplasty when lysis failed or was contraindicated (group B, 26 patients). The cumulative patency rates were compared by using a Kaplan-Meier life table analysis. All patients underwent routine color duplex ultrasound scanning/ankle brachial index measurements at 30 days, 6 months, and every 6 months thereafter. RESULTS: Demographic and clinical characteristics and indications for intervention were comparable in both groups. The mean follow-up period was 54.1 and 46.2 months in group A and group B, respectively. There were four perioperative complications in group A (13%) and seven perioperative complications in group B (27%). Initial technical success and 30-day secondary graft patency rates were 100% in both groups. Overall, 17 of 31 patients (55%) had open grafts, with no further revisions in group A and six of 26 patients (23%) in group B requiring further revisions (P =.012). Nine of 31 grafts (29%) failed in group A versus 15 of 26 grafts (58%) in group B (P =.027). The rate of limb loss was comparable in both groups (6% vs 12%). The overall cumulative secondary patency rates at 6 months and 1, 2, 3, 4, and 5 years were 100%, 93%, 85%, 72%, 67%, and 62% for group A and 100%, 96%, 88%, 76%, 63%, and 45% for group B (P =.035). Thirty-five further interventions were needed to maintain graft patency in group B (mean, 1.35; range, 0-3) versus five further interventions in group A (mean, 0.16; range, 0-1; P <.05). CONCLUSION: Thrombectomy/open surgical repair is superior to lysis/PTA (or thrombectomy/balloon angioplasty) for the treatment of failed above-knee PTFE FPGs with anastomotic stenoses. Therefore, balloon angioplasty should be reserved for patients who are at high risk for surgery.     

Percutaneous management of perianastomotic stenosis in arteriovenous fistulae: results of a prospective study

Surgical creation of new anastomosis has been proposed as the preferred treatment for perianastomotic stenoses of fistulae. However, disadvantages of surgical approach have included (1) frequent conversion of fistula to a graft by using synthetic graft material to create a new anastomosis, (2) shortening the length of the cannulation segment by proximal autologous arteriovenous neoanastomosis, and (3) abandoning the fistula altogether in favor of a synthetic graft. We report the results of a prospective study using percutaneous balloon angioplasty (PTA) to treat fistulae with perianastomotic lesions. Seventy-three consecutive patients undergoing 112 PTA procedures for the treatment of perianastomotic lesions were studied. Primary and secondary patency rates were calculated. Procedure success, procedure-related complications, and conversion of fistulae to grafts were recorded. The initial success rate was 97%. The degree of stenosis before and after PTA was 81 +/- 9 and 11+/-11%, respectively. Primary patency rates at 6, 12, and 18 months were 75, 51, and 41%, respectively. Secondary patency rates at 6, 12, and 18 months were 94, 90, and 90%, respectively. Grade I hematoma occurred in three and vein rupture in two cases. No grafts were inserted. These outcomes are superior to those that have been reported for surgery. The outpatient PTA is safe and effective for the management of perianastomotic stenosis. Because of its advantage of fistula preservation, the percutaneous approach should be considered as the preferred first-line therapy for the management of perianastomotic fistula lesions.     

Restoration of acutely thrombosed arterio-venous fistulae by rTPA and percutaneous angioplasty

Acute thrombosis in native arterio-venous fistulae (AVF) results in considerable patient morbidity. Interventional radiology (IR) comprising thrombolysis and percutaneous transluminal angioplasty (PTA) is well established in the management of thrombosed polytetrafluoroethylene (PTFE) grafts. However its role in thrombosed AVF is uncertain. We looked retrospectively at the role of IR in re-establishing blood flow in acutely throm-bosed AVF. Between 1992-2000, 21 episodes of acutely thrombosed AVF in 15 patients (9 females; age range 29-80yrs) were referred for intervention. All fistulae were being used for haemodialysis at the time. Diagnosis was established by angiography and thrombolysis with recombinant tissue plasminogen activator (rTPA) was attempted in all patients. Discrete stenoses when present (n=12) were then treated with PTA and resistant or recurrent stenoses were managed by stent insertion (n=3). Patients were then heparinised for 24 hours. Technical success as defined by radiological patency was achieved in 86% cases. Clinical success i.e. the ability to reuse of the fistula for haemodialysis was achieved in 62% of the interventions, where patency rates at 3 and 6 months were 92% and 69% respectively. Five patients had recurrence of thrombosis >3 months after the primary procedure, 3 had successful reintervention. Minor local bleeding was the only complication. Our retrospective study shows rTPA and PTA is successful in the management of acutely thrombosed AVF. We advocate the routine use of IR as a valuable technique for prolonging the life of native AVF in patients on maintenance haemodialysis.     

Cutting balloon angioplasty for carotid artery in-stent stenosis supported by three-dimensional rotational angiography with automated vessel analysis software

In-stent stenosis is a possible long-term complication of carotid artery stenting. A simple and safe technique of cutting balloon angioplasty is described for carotid in-stent stenosis. The stented vessel is imaged by three-dimensional (3D) rotational angiography, the acquired projection images are transferred to a workstation, and the stenotic lesion and implanted stent are reconstructed. The diameter of the implanted stent in the stenotic region is measured by automated analysis software. Cutting balloon angioplasty carries the risk of vessel injury by the cutting balloon microblades, but the implanted stent acts as a barrier to protect the vessel. Therefore, cutting balloon inflation up to the stent diameter is safe and results in maximal vessel dilation. The key to success is precise measurement of the stent diameter and choice of a cutting balloon catheter of the appropriate size. 3D rotational angiography provides high-quality images of the vasculature of a stented vessel and a reference for intervention based on absolute measurements. Cutting balloon angioplasty supported by 3D rotational angiography with automated vessel analysis software should be considered as a treatment strategy for high-grade carotid artery in-stent stenosis.     

A proposed management algorithm for fistulae between hemodialysis access circuits and adjacent veins

Purpose: Fistulae between an arteriovenous hemodialysis graft (AVG) or fistula (AVF) and an adjacent vein are an unusual complication of hemodialysis access. Such fistulae may theoretically cause steal syndrome, extremity edema, or access dysfunction. We sought to use our experience and existing literature to develop a management algorithm for this access complication. Methods: Twelve patients with AVG/AVF to adjacent vein fistulae found on fistulography were identified using a quality assurance database. Indications for fistulography, treatment rendered for both the fistulae and access stenosis, and outcome of treatment were determined. AVG/AVF to adjacent vein fistulae, when identified and considered to be significant, were treated with embolization. Results: Five out of twelve patients had successful embolization of their AVG/AVF to adjacent vein fistulae. Reasons for treatment included partial thrombosis of the access to the level of the fistula (n=1), contribution to bleeding during dialysis (n=1), and concern for competing flow causing thrombosis (n=5). No recurrence was identified. Seven patients did not undergo embolization either because of failure to recognize the fistula (n=3) or determination that treatment was not indicated (n=4). Two untreated fistulae were found occluded at follow-up. Additional access treatment included angioplasty (n=11), covered stent (n=1), and mechanical thrombectomy (n=3). Conclusions: The significance of AVG/AVF to adjacent vein fistulae remains unclear; some resolve spontaneously, possibly related to PTA of outflow stenosis. Embolotherapy is an effective treatment for such fistulae when determined to be significant.     

Comparison of early clinical results of contact laser thermal angioplasty with a metal hot tip with balloon angioplasty

Contact laser thermal angioplasty with a metal hot tip heated by an Argon laser system (Trimedyne Inc.) was performed on 34 peripheral arterial occlusive or stenotic regions (7 iliac, 20 femoral and 7 popliteal arteries) in 22 patients with ASO. The early clinical results of laser angioplasty were investigated by comparing those of 15 patients treated by percutaneous transluminal balloon angioplasty (PTA). There was no perforation of the arterial wall caused by thermal ablation with the hot tip heated by repeated pulses under power conditions of 10 watts of laser energy for 5 seconds. Detachment of the hot tip caused by frequent healing without a sufficient period of tip cooling was observed in 2 cases. Acute thrombosis was observed in 1 patient during reconstruction of the proximal artery. The initial success rate of laser angioplasty and PTA was 91.2% and 86.7%, respectively. Re-stenosis or occlusion was observed in 7 of 31 regions 6 months after laser angioplasty. Satisfactory results were not obtained in the femoral artery. The overall patency rate of laser angioplasty and PTA was 77.4% and 69.2%, respectively. The initial success rate of laser angioplasty in totally obstructed arterial regions was higher than that of PTA.