True aneurysm formation in axillofemoral bypass with a reinforced ePTFE graft-a case report

Since improvement in reinforced expanded polytetrafluoroethylene (ePTFE) grafts, true aneurysm and pseudoaneurysm formation have become relatively rare complications after axillofemoral reconstruction. This is a case report of a true aneurysm of an axillofemoral graft. The true aneurysm occurred 29 months after insertion of a reinforced ePTFE graft for aortoiliac occlusive disease. A mid-graft true aneurysm was identified during examinations without any trauma history. Continuous long-term follow-up is recommended for these reinforced ePTFE grafts because of rare aneurysm formation, preferably using duplex ultrasonography.     

Long-term Outcome of a Cuffed Expanded PTFE Graft for Hemodialysis Vascular Access

BACKGROUND: Development of venous outflow stenosis has been a major obstacle in maintaining the patency of dialysis vascular grafts. In the present study, we retrospectively analyzed the long-term results of cuffed expanded polytetrafluoroethylene (ePTFE) and non-cuffed (standard) ePTFE grafts placed for hemodialysis access. MATERIALS AND METHODS: A total of 67 patients who underwent placement of either cuffed (n = 41) or standard (n = 26) ePTFE grafts were retrospectively analyzed. There were no significant differences between the two groups with regard to age, gender, cause of end-stage renal disease, and anatomic placement of the graft. Endpoints consisted of primary (without any intervention) and secondary (with radiological or surgical intervention) graft patency rates at 1-3 years. RESULTS: There was a trend toward better primary graft patency rates in the cuffed versus the standard ePTFE: 37.7% vs. 25.7% at 1 year, 35% vs. 10.3% at 2 years, 28% vs. 5.1% at 3 years, respectively (p = 0.086, Kaplan-Meier). Secondary patency rates in the cuffed group were significantly superior (p = 0.047) to those in the standard group (81.8% vs. 56.1% at 1 year, 61.8% vs. 46.3% at 2 years, 51.5% vs. 33.1% at 3 years, respectively). Thrombosis as a cause of complete graft failure was significantly higher (34%) in the standard group than in the cuffed group (9%) (p = 0.0125). CONCLUSIONS: Compared to the standard ePTFE, the cuffed ePTFE graft provided better long-term outcome, especially in terms of secondary patency rates after radiological intervention.     

Prospective randomised trial of distal arteriovenous fistula as an adjunct to femoro-infrapopliteal PTFE bypass.

OBJECTIVES: To compare graft patency and limb salvage rate following femoro-infrapopliteal bypass using ePTFE grafts with and without the addition of adjuvant arterio-venous fistula. DESIGN: A prospectively randomised controlled trial. MATERIALS: Patients referred to two teaching hospital vascular surgery units in the U.K. for the treatment of critical limb ischaemia. METHODS: Eighty-seven patients (M:F; 2.3:1) undergoing 89 femoro-intrapopliteal bypass operations with ePTFE grafts for critical limb ischaemia were randomly allocated to have AVF included in the operative procedure (n = 48) or to a control group without AVF (n = 41). An interposition vein-cuff was incorporated at the distal anastomosis in all patients. RESULTS: The cumulative rates of primary patency and limb salvage at 1-year after operation for patients with AVF were 55.2% and 54.1% compared to 53.4% and 43.2%, respectively, for the control group. The differences between the AVF and control groups did not reach statistical significance, in terms of either graft patency or limb salvage, at any stage after operation (Log-Rank test). CONCLUSIONS: AVF confers no additional significant clinical advantage over interposition vein cuff in patients having femoro-infrapopliteal bypass with ePTFE grants for critical limb ischaemia.     

Development of intimal hyperplasia in six different vascular prostheses.

OBJECTIVES: to compare six vascular prostheses for the development of intimal hyperplasia (IH) in a sheep model. MATERIAL AND METHODS: prostheses tested were gelatin sealed Dacron (GSD), fluoropassivated Dacron (FPD), FluroIpassiv TM (FD), expanded polytetrafluoroethylene (ePTFE), carbon-lined expanded polytetrafluoroethylene (CL-ePTFE) and vascular access graft (VAG). Sixty-two adult female Merino sheep (35-45 kg) were used. Elliptical graft patches were implanted into the left common carotid artery using one of the six graft types: GSD (n=10), FPD (n=10), FD (n=12) VAG (n=10), ePTFE (n=10), or CL-ePTFE (n=10). Four weeks later grafts were removed for histopathological assessment and measurement of the degree of IH obtained on a computerised image analysis system. RESULTS: IH indices were significantly less for FPD (0.191+/-0.095, p<0.05), FD (0.199+/-0. 081, p<0.05), ePTFE (0.213+/-0.078, p<0.05) and CL-ePTFE (0.161+/-0. 066,p<0.01), compared to the GSD group (0.287+/-0.077). The VAG group (0.257+/-0.091) showed no difference compared to GSD. There was no significant difference between the FPD, FD, ePTFE and CL-ePTFE grafts. CONCLUSION: this study indicates that less IH occurred in the two-ePTFE grafts and two fluoropolymer coated Dacron grafts than in gelatin sealed Dacron or polyurethane grafts.     

Sutureless nonocclusive bypass surgery in combination with an expanded polytetrafluoroethylene graft. Laboratory investigation

OBJECT: Cerebral aneurysms that cannot be treated by clip or coil placement can be treated with high-flow bypass surgery using techniques such as the excimer laser-assisted nonocclusive anastomosis (ELANA). To simplify the technique, a sutureless ELANA (SELANA) was developed in combination with an expanded polytetrafluoroethylene (ePTFE) graft. METHODS: In 18 rabbits a bypass was constructed on the abdominal aorta using the SELANA technique with an ePTFE graft, resulting in 18 bypasses and 36 anastomoses. Short-term effects were analyzed in the first 2 weeks and at 2 and 3 months after the procedure. Patency was evaluated using quantitative ultrasound flowmetry. The anastomotic sites were studied using scanning electron microscopy. RESULTS: Construction of the bypass using the SELANA technique was easier and faster (15-25 minutes) compared with bypasses made with the ELANA technique (> 90 minutes). At the end of follow-up, 16 of 18 bypasses were patent. Of 36 SELANA anastomoses, 32 could be completed without short temporary occlusion of the recipient vessel. Scanning electron microscopy showed complete coverage of all anastomoses with neointimal repair tissue after 10 days. CONCLUSIONS: The SELANA technique provides further advantages over the conventional ELANA technique in ease of use and shortening of procedure time. The patency rate in this series was 89% and neointima repair tissue at the anastomosis site was complete after 10 days. Further experimental studies of the long-term patency and safety of this technique are necessary before clinical application.     

Open surgical and endovascular treatment of superior vena cava syndrome caused by nonmalignant disease

OBJECTIVES: The purpose of this study was to evaluate the role of endovascular and open surgical reconstructions in patients with superior vena cava (SVC) syndrome caused by nonmalignant disease. METHODS: Clinical data from 32 consecutive patients who underwent endovascular or open surgical reconstruction of central veins because of symptomatic benign SVC syndrome between November 1983 and June 2001 were retrospectively reviewed. RESULTS: The study included 17 male and 15 female patients (mean age, 38 years; range, 5-69 years). Presenting symptoms were head fullness (n = 26), dyspnea or orthopnea (n = 23), headache (n = 17), or dizziness (n = 11); physical signs were head swelling (n = 31), chest wall collateral vessels (n = 29), facial cyanosis (n = 18), or arm swelling (n = 17). Etiologic factors included mediastinal fibrosis (n = 19), indwelling catheter (n = 8), idiopathic thrombosis (n = 4), or post-surgery (n = 1). Two patients were heterozygous for factor V Leiden; 1 patient had antithrombin III deficiency. Twenty-nine patients underwent surgical reconstruction with 31 bypass grafts: spiral saphenous vein (n = 20), superficial femoral vein (n = 4), human allograft (n = 1), or expanded polytetrafluoroethylene (ePTFE, n = 6). Eleven patients underwent percutaneous transluminal angioplasty or stenting; 3 primary and 8 secondary endovascular procedures were performed to treat graft stenosis (n = 7) or occlusion (n = 1). There were no early deaths. Five early graft failures in 3 ePTFE grafts and 2 bifurcated vein grafts (thrombosis, n = 4; stenosis, n = 1) were successfully treated with open surgical revision. Over a mean follow-up of 5.6 years (range, 0.4-16.6 years) in surgical patients, 17 additional secondary interventions were performed in 8 patients, 14 endovascular and 3 surgical. Primary, assisted primary, and secondary patency rates of surgical bypass grafts were 63%, 79%, and 85%, respectively, at 1 year, and 53%, 68%, and 80%, respectively, at 5 years. Graft patency was significantly higher in vein grafts compared with ePTFE grafts (P =.02). Mean follow-up after percutaneous transluminal angioplasty or stenting was 3.1 years (range, 1 day-11.7 years). Twelve secondary endovascular interventions were performed in 6 patients (primary group, 3 of 3; secondary group, 3 of 9 grafts in 8 patients) to maintain patency in 11 of 12 reconstructions. Mean follow-up in the entire patient cohort was 5.3 years (range, 0.4-16.6 years). In 79% of patients symptoms had resolved or were significantly improved at last follow-up. CONCLUSIONS: Surgical treatment of benign SVC syndrome is effective over the long term, with secondary endovascular interventions to maintain graft patency. Straight spiral saphenous vein graft remains the conduit of choice for surgical reconstruction, with results superior to those with bifurcated vein and ePTFE. Endovascular treatment is effective over the short term, with frequent need for repeat interventions. It does not adversely affect future open surgical reconstruction and may prove to be a reasonable primary intervention in selected patients. Patients who are not suitable for or who fail endovascular intervention merit open surgical reconstruction.     

Challenges of hemodialysis access for high risk patients: Impact of mesenteric vein bioprosthetic graft

Objective: The purpose of this study is to compare in a prospective fashion the performance of a new bioprosthesis, the mesenteric vein bioprosthesis (MVB), in patients who have had multiple failed ePTFE grafts. Performance measures include primary patency rates, assisted-primary patency rates, secondary patency rates, complications, and the number of interventions required to maintain graft patency. Study: From October 1999 to February 2002, 276 hemodialysis access grafts were implanted in a multicenter study. Of those grafts, 74 were placed in patients with a prior history of 3 failed prosthetic grafts (mean = 3.5 grafts, range = 3-6 grafts). Fifty-nine grafts were constructed with MVB, and 15 grafts with ePTFE as a concomitant control. Mean follow-up was 11.5 months. In the MVB group, 79.7% were African-Americans, 61% were females, and 23.7% were hypercoagulable. Of the ePTFE group, 86.7% were African-Americans, 46.7% were female, and 13.2% were hypercoagulable. Results : Per Kaplan-Meier curves, the primary patency rate of the MVB group at 12 months was 33% vs the ePTFE group of 18% (p=0.120); the assisted-primary patency rates at 12 months were 45% MVB vs 18% ePTFE (p=0.011). The secondary patency rates at 12 and 24 months for the MVB group were 67% and 59%, respectively, vs 45% and 15% for the ePTFE group (p=0.006). During the follow-up time period, 80% of the ePTFE grafts were abandoned compared to 34% of the MVB group. Infection and thrombosis rates in the MVB group were lower than the ePTFE group. The infection rate for the MVB group requiring intervention was 0.07 events/graft year (gt/y) compared to 0.30 events/gt-y for ePTFE (p=0.04). A thrombosis rate of 0.69 events/gt-y occurred in the MVB group whereas 2.50 events/gt-y presented in the ePTFE group (p<0.01). Conclusion: In this study, high-risk patients (defined as those having multiple failed prosthetic grafts for hemodialysis) in whom the MVB conduit for hemoaccess was implanted, showed significant improvement in assisted-primary and secondary patency rates compared to the ePTFE cohort. The MVB group, however, did not have a statistically better primary patency rate compared to the ePTFE group. The MVB patient also had fewer thrombotic and infectious events and an overall reduction in the number of interventions while maintaining a permanent access site. This new bioprosthesis should be the conduit of choice in the complex group of patients as it offers assisted-primary and secondary patency rates similar to those commonly experienced by patients without a history of multiple graft failures.     

Comparison of carbon-impregnated and standard ePTFE prostheses in extra-anatomical anterior tibial artery bypass: a prospective randomized multicenter study.

OBJECTIVES: The aim of this study was to find out whether carbon impregnated ePTFE vascular grafts have better long-term patency or limb salvage rates than Standard ePTFE vascular grafts in crural revascularization in patients with chronic critical ischemia. DESIGN: Prospective randomized multicenter trial. Study endpoints were 36 months follow-up, major amputation or death. MATERIALS: We used 6mm carbon ePTFE (Carboflo) and 6mm standard ePTFE vascular grafts (both C.R. BARD Inc./IMPRA). METHODS: From June 1995 to November 1998, 283 patients were randomly assigned either to carbon (C) (n=140) or to standard (St) ePTFE (n=143) vascular grafts at 19 centres. A standard protocol was used with lateral extra-anatomic course of the graft to the anterior tibial artery and of a distal vein patch or cuff. More than 90% of the patients had rest pain or gangrene. RESULTS: Two hundred and sixty-five (C=130; St=135) patients could be analysed in the intention-to-treat (ITT) group. Primary patency, secondary patency and limb salvage rates after 36 months were 33, 43 and 67% in the carbon- and 30, 38 and 58% in the standard PTFE group, respectively, (log-rank test: p=0.20, 0.12 and 0.16). Additional analyses were made per protocol (PP) and as-treated (AT). The retrospective power of the study was calculated as 79 and 83%. CONCLUSION: The ITT, PP and AT analysis, showed no statistically significant advantage of the carbon ePTFE vascular graft in terms of patency or limb salvage over the standard ePTFE vascular graft at 36 months.     

严重十二指肠损伤的治疗

目的探讨严重十二指肠损伤的治疗方法。方法回顾8年间手术治疗的严重十二指肠损伤和胰腺损伤38例患者的临床资料。结果十二指肠憩室化手术8例,5例痊愈,2例肠瘘,死亡1例。胰十二指肠切除9例,3例痊愈,胰瘘6例其中死亡3例。十二指肠直接修补或补片修补16例,13例痊愈,2例发生肠瘘,死亡1例。5例十二指肠修补+胰头切除胰腺空肠吻合(保留十二指肠的胰头切除),4例痊愈,1例胰瘘;其中3例行胰腺空肠捆绑吻合患者,无胰瘘发生,均痊愈出院。结论大部分十二指肠损伤可行十二指肠直接修补或补片修补加可靠的十二指肠和空肠造瘘术;对合并严重胰头部损伤者可在上述手术基础上行保留十二指肠的胰头切除,可获得比较满意的效果。不要轻易使用十二指肠憩室化手术和胰十二指肠切除手术。     

The midterm results of stent graft treatment of thoracic aortic injuries

INTRODUCTION AND OBJECTIVES: Several publications document the technical feasibility of stent graft repair of aortic transection. We report our mid-term results of endovascular repair of thoracic aortic transections using covered stent grafts and compare this to a cohort undergoing open repair during the same time period to demonstrate the shift in practice pattern at our institution. MATERIALS AND METHODS: A retrospective review of patients who sustained blunt thoracic transection was undertaken. Medical records were examined to identify the clinical outcome of the procedure, and follow-up CT scans were reviewed to document adequate treatment of the transection. Outcome measures include procedure-related mortality, neurological morbidity, and successful immediate and mid-term coverage of the thoracic false aneurysm and absence of graft migration or endoleak. RESULTS: From July, 2000 to October, 2004, 27 patients were identified with descending thoracic aortic transection at our level I trauma center. Fourteen patients were managed nonoperatively, five patients underwent thoracotomy and direct aortic repair, and eight patients underwent endoluminal stent graft repair. Of the endovascular group (n=8), repairs were performed with stacked AneuRx aortic cuffs (Medtronic, Inc., Minneapolis, MN) (n = 6), a Gore thoracic aortic stent graft (Thoracic EXCLUDER; W.L. Gore, Flagstaff, AZ) (n=1), or a Medtronic Talent thoracic endograft (Medtronic, Inc.) (n=1). Access for stent graft deployment was the common femoral artery (n=2), iliac artery (n=4), or distal abdominal aorta (n=2). Completion arch aortography and postoperative CT scanning confirmed successful management of the aortic transection in each patient. There were no procedure-related deaths, paraplegia, or stroke. Postoperative complications included a brachial artery thrombosis in one patient as well as an external iliac artery dissection and acute renal failure in a second patient for a complication rate of 37.5%. Two patients died as a result of their injuries unrelated to the stent graft repair. Mean follow-up of 16.6 mo has shown no evidence of endoleak or stent graft migration. Of the open repair group (n=5), one patient died in the operating room during attempted aortic repair, and one patient had a postoperative stroke. CONCLUSIONS: Due to technical success and absence of delayed complications including endoleak and graft migration, stent graft repair of traumatic aortic transection has replaced open aortic repair as the primary treatment modality in the multiply injured trauma patient at our institution. The postoperative complication rate observed in this small series tempers the success to some degree, but the severity of the complications compares favorably with those observed in the open repair group.     

Viability of engineered vessels as arterial substitutes.

The search for vessel substitutes to replace small-/medium-caliber vessels is an ongoing concern for vascular surgeons. Engineered vessels were designed for use as arterial equivalents and assessed in an in vivo model in dog. Three study groups were established: clinical expanded polytetrafluoroethylene (ePTFE; control, n = 24), ePTFE seeding with endothelial cells (EC graft, n = 12), and ePTFE with a fibroblast matrix seeded with EC (FM+EC graft, n = 12). Grafts were subjected to a custom-designed femoral ex vivo circuit and implanted in the carotid artery for 60 days. The viability of the prosthetic grafts was evaluated. The ex vivo circuit revealed that the presence of a fibroblast matrix induced over double the cell retention compared to EC grafts. A significant reduction in platelet adhesion in EC grafts was observed. After their in vivo implantation, the engineered vessels were more efficient at avoiding occlusion than the prosthetic grafts. The FM+EC grafts induced more endothelialization than those seeded with ECs alone. Intimal hyperplasia response was reduced in the EC substitutes. Significant differences in apoptotic cells emerged between the EC and control ePTFE grafts. In conclusion, engineered vessels showed improved initial patency over ePTFE grafts. The EC graft was best at combating restenosis, a good indicator of the long-term efficiency of the graft.     

An artificial vascular graft is a useful interpositional material for drainage of the right anterior section in living donor liver transplantation.

Congestion in the anterior section in a right liver (RL) without a middle hepatic vein (MHV) may lead to graft dysfunction. To solve this problem, an RL draining MHV branches with autologous or cryopreserved vessels can be introduced. However, these vessels are often unavailable, and their preparation is time-consuming. An expanded polytetrafluoroethylene (ePTFE) graft may be used for anterior section drainage. Between February and November 2005, 26 recipients underwent RL liver transplantation draining MHV branches with an ePTFE graft (group P). Twenty-six ePTFE grafts (6 or 7 mm in internal diameter) drained 35 MHV branches on the back table to the graft right hepatic vein or to the recipient's inferior vena cava. The patency of the ePTFE graft was checked with computed tomography scans of the liver. The outcome of group P was compared with those of an RL group with MHV (group M, n=17) and an RL group without reconstruction of MHV or its tributaries (group R, n=85). The 1-month and 4-month patency rates (PRs) of the ePTFE grafts were 80.8% (21/26) and 38.5% (10/26). All showing early obstruction of the ePTFE graft had congestion in the anterior section, but all showing late obstruction were asymptomatic. The 1-month PRs of group P were comparable to, but the 4-month PRs were lower than, those of group M (both 94.1%; P<0.05). However, 1-year patient and graft survival rates of group P (both 100%) were comparable to those of group M (94.1% and 100%) and better than those of group R (83.5% and 88.2%; P<0.05). In conclusion, the early PR of group P was good, and late obstruction of the ePTFE graft had no impact on congestion in the anterior section or patient survival. Therefore, an ePTFE graft may be a useful interposition material for anterior section drainage in RL transplantation without serious complications.     

Comparison of femorofemoral and aortofemoral bypass for aortoiliac occlusive disease

BACKGROUND: Role and results of femorofemoral bypass grafting, usually reserved to high-risk patients affected with unilateral iliac artery occlusion, are still debated. METHODS: EXPERIMENTAL DESIGN: retrospective clinical study. SETTINGS: University Hospital. PATIENTS: seventy-six high-risk patients (group 1) who underwent a primary expanded polytetrafluoroethylene (ePTFE) externally supported femorofemoral bypass graft were retrospectively compared to two additional groups of patients selected from the entire series of patients who underwent an aortobifemoral bypass graft. Patients of group 2 (n=80) were randomly chosen to determine differences in risk factors, associated diseases, previous abdominal operations, operative indications, preoperative findings and outcome. Patients of group 3 (n=50) were matched for sex, risk factors, associated diseases, previous abdominal operations, operative indications and preoperative findings with those of group 1 to assess the importance of the type of operation in determining the outcome of the procedure. RESULTS: Postoperative mortality (6, 4 and 6%, respectively), 5-year primary and secondary patency (71, 80, 83% and 80, 87, 87%, respectively) and limb salvage rates (78, 87 and 87%, respectively) were similar among the groups (p=NS, p=NS, p=NS, respectively). Five-year survival rate of group 2 was significantly better than that of group 1 and 3 (p<0.04 and p<0.04, respectively). CONCLUSIONS: Primary ePTFE externally supported femorofemoral bypass graft in high-risk patients is safe and produces long-term results similar to aortofemoral reconstruction.     

Dacron versus polytetrafluoroethylene for Y-aortic bifurcation grafts: a six-year prospective, randomized trial.

BACKGROUND. A prospective, randomized trial was conducted to compare Dacron with expanded polytetrafluoroethylene (ePTFE) in reconstructive aortoiliac surgery. No comparable trial with a prospective, randomized design with a comparable number of patients or an equal long-term follow-up period can be found in the literature. METHODS. Between 1984 and 1989, 165 patients were randomized for either Dacron or ePTFE on the basis of age, sex, indication for surgery, diabetes, nicotine consumption, runoff, and operative approach. The two groups were well matched for randomization criteria, as well as the incidence of aneurysms. RESULTS. No statistically significant difference was found between the two graft materials in terms of patency rates (corrected 3-year patency rates: Dacron = 95% vs ePTFE = 95%; Breslow, p = 0.83; Mantel-Cox, p = 0.74). Subgroup analysis comparing long-term patency rates of the two graft materials and relating them to poor runoff, good runoff, aneurysms, and arterial occlusive disease also failed to show any significant differences between ePTFE and Dacron. Early graft failure (n = 6; 3.6% of the patient population; p = 0.045) and severe abdominal graft infection (n = 3; 1.8% of the total population) were seen only in ePTFE grafts. However, these did not affect the corrected long-term patency rate of ePTFE grafts. There were five late graft failures with PTFE (3.0%) and four with Dacron (2.4%). CONCLUSIONS. Graft materials currently available for aortoiliac repair were comparable in terms of corrected long-term patency rates. The alleged advantages of PTFE were not confirmed by our data. PTFE grafts were associated with a higher rate of complications, and more redo operations were required to duplicate the results obtained with Dacron.     

Clinical results with an ePTFE inflow conduit for mechanical circulatory support

BACKGROUND: Neurologic complication is an adverse event associated with mechanical circulatory support. To decrease the incidence of embolic cerebrovascular accidents (CVA) during support with the Novacor left ventricular assist system (LVAS), an expanded polytetrafluoroethylene (ePTFE) inflow conduit has been developed and introduced clinically. METHODS: Using clinical data from Europe and Canada, we conducted a retrospective analysis of the incidence of embolic CVA with the ePTFE inflow conduit (n=88) in comparison with the previously used polyester inflow conduits (n=310, including Vascutek n=155 and Cooley n=155). We calculated freedom from embolic CVA, risk reduction for embolic CVA, and linearized rates of embolic CVA. RESULTS: A significant decrease in the incidence of embolic CVA was demonstrated with the ePTFE conduit (ePTFE 10% vs polyester 23%, p=0.002). Kaplan-Meier analysis of freedom from embolic CVA at 180 days after implantation was 86% for the ePTFE group vs 72% for the polyester group (log-rank test, 0.0185). We also found an associated risk reduction of 55% in CVA occurrence in the ePTFE group when compared with the Polyester group (hazard ratio, 0.445; 95% confidence limit, 0.222-0.890; p=0.0221). Linearized CVA rates also were decreased at all time intervals after implantation in the ePTFE group. CONCLUSIONS: Preliminary clinical results with the newly introduced ePTFE inflow conduit provide compelling evidence that the ePTFE conduit material significantly decreases thromboembolic complications during mechanical circulatory support with the Novacor LVAS.     

膨体聚四氟乙烯补片修复胆管缺损的实验研究

目的 探讨膨体聚四氟乙烯（ePTFE)修复胆管缺损的可能性。方法 36条重庆地区成年犬,通过切除部分胆管壁（A组,14条）、整段切除2－4cm胆总管（B组,10条）和完全结扎胆总管（C组,5条;D组,7条）的方式建立胆管损伤模型,分别采用ePTFE补片修补胆管缺损,管形材料替代胆管,间置材料在胆囊、十二脂肠或空肠吻合修复胆管。观察动物在手术前后的活动状况,结合胆道造影了解胆通畅情况,并在术后3天,2、4、8、12及52周切取胆管修复处的组织,观察胆管组织的变化,不同手术方式对肝脏形态结构的影响。结果 A组采用ePTFE补片修补胆管,胆管上皮能覆盖材料表面,通畅率达75％（9／12）,胆汁引流通畅,肝脏无损害;B组通畅率为40％（4／10）,伴有不同程度的肝脏形态结构改变;C组和D组的材料均被排除,形成胆囊十二指肠或胆囊空肠瘘。结论 ePTFE补片具有操作简便、通畅率高的特点,可作为修补胆管缺损的材料。     

Management of blunt thoracic aortic injuries: endovascular stents versus open repair

BACKGROUND: Endovascular stent graft (EV) technology has been successfully adapted to the repair of blunt traumatic aortic injuries. The purpose of this study was to compare the outcomes of patients treated with EV repair and open repair after blunt thoracic aortic trauma. METHODS: A review of a tertiary trauma center's prospective trauma registry identified all patients who suffered a blunt traumatic thoracic aortic injury over an 11-year period (1991-2002). Operative interventions and outcomes were then compared. RESULTS: Over an 11-year period, 18 patients underwent repair of a blunt thoracic aortic injury (EV, 6; open, 12). There were no significant differences in demographics, injury, or crash statistics between groups. The open group had a 17% early mortality rate (n = 2), a paraplegia rate of 16% (n = 2), and an 8.3% incidence of recurrent laryngeal nerve injury (n = 1). This is in contrast to a 0% rate of mortality, paraplegia, and recurrent laryngeal nerve injury in the EV group. A definite trend toward decreased morbidity, mortality, intensive care unit length of stay, and number of ventilator-dependent days was seen with EV repair. CONCLUSION: We observed a clear trend toward improved outcomes after EV repair of thoracic aortic injuries compared with standard open repair. EV repair is emerging as the preferred method of repairing blunt thoracic aortic injuries in trauma patients with multiple injuries.     

Infrainguinal arterial reconstructions with vein grafts in patients with prior aortic procedures: the influence of aneurysm and occlusive disease

PURPOSE: This study assessed whether infrainguinal reconstructions with autogenous vein (IR) performed in patients with prior abdominal aortic aneurysm (AAA) repairs have altered graft patency, compared with those in patients who have undergone prior aortobifemoral bypass grafting procedures (ABF) for aortoiliac occlusive disease. METHODS: From 1979 to 1998, 54 patients with prior aortic reconstructions underwent 64 autogenous single-segment saphenous IRs solely for infrainguinal occlusive disease. Included in this cohort were 30 IRs with an earlier AAA repair and 34 IRs with an earlier ABF repair. During the same period, 1274 patients underwent 1642 autogenous vein lower-extremity bypass grafting procedures (LEB). Lower-extremity native arterial (AAA, n = 6; ABF, n = 11) and vein graft diameters (AAA, n = 6; ABF, n = 6) were determined by means of angiography and duplex ultrasonography, respectively. The three reconstruction groups (AAA, ABF, LEB) were compared. RESULTS: The patients in the three groups were similar in sex, indication for operation, proximal and distal anastomotic site, and number of distal runoff vessels. The cumulative 5-year primary graft patency rate in the AAA group (92% +/- 5%) was significantly higher (P <. 001) than that in the LEB group (63% +/- 2%) and the ABF group (44% +/- 11%). Furthermore, cumulative 5-year primary patency was decreased in the ABF group compared with the LEB group (P =.05). A significant increase in both native arterial (P =.001) and vein graft diameter (P <.05) was demonstrated by using linear regression and a Student t test, respectively, in the AAA group compared with the ABF group. CONCLUSION: These data demonstrate that, compared with those in patients without a previous aortic procedure, IRs in patients with prior AAA repairs have significantly improved graft patency, and IRs in patients with prior ABF reconstructions for aortoiliac occlusive disease have significantly decreased graft patency. Larger arterial diameter and altered vein graft adaptation may contribute to the superior long-term outcomes of IRs in patients with prior AAA repairs.     

The value of duplex surveillance after open and endovascular popliteal aneurysm repair

OBJECTIVE: The objective of this study was to determine the clinical value of vascular laboratory surveillance after open or endovascular repair of popliteal aneurysm by analysis of the frequency and nature of secondary interventions performed. METHODS: Over an 8-year period, 55 popliteal artery aneurysms were repaired in 46 men (mean age, 72 years) by aneurysm ligation and bypass grafting (vein, 37; prosthetic, 7), endoaneurysmorrhaphy and interposition grafting (prosthetic, 3; vein, 1), or endograft exclusion (n = 7). Indications for intervention included aneurysm thrombosis with critical limb ischemia (n = 8), symptomatic (n = 10) or asymptomatic (n = 37), >1.75 cm popliteal aneurysm with mural thrombus. Catheter-directed thrombolysis was used in three limbs to restore aneurysm and tibial artery patency before open repair. Duplex ultrasound surveillance was performed after repair to identify residual and acquired lesions. Life-table analysis was used to estimate repair site intervention-free (primary) and assisted-primary patency. RESULTS: During a mean 20-month follow-up interval, 20 secondary procedures were performed in 18 (31%) limbs to repair duplex-detected graft stenosis (n = 10), repair site thrombosis (n = 5), vein graft aneurysm (n = 3), graft entrapment (n = 1), or type 1 endoleak (n = 1). Primary patency was 76% and 68% at 1 and 3 years, and was uninfluenced by tibial artery runoff status or type of bypass conduit. Open (n = 12) or endovascular (n = 8) secondary procedures were performed on 15 (12 vein, 3 prosthetic) bypass grafts, 2 endografts, and 1 interposition graft. Mean time to repair graft stenosis (11 months) was shorter than to repair of vein graft aneurysm (37 months). Assisted-primary patency was 93% and 88% at 1 and 3 years; redo bypass grafting was required and successful in five limbs. Limb salvage was 100%. CONCLUSIONS: One third of popliteal artery aneurysms repaired by open or endovascular procedures required a secondary intervention within 2 years of repair. Repair-site surveillance using duplex ultrasound was able to identify lesions that threaten patency, which resulted in excellent assisted patency and limb preservation rates when corrected.     

Clinical results of surgery for retroperitoneal sarcoma with major blood vessel involvement

PURPOSE: The study was conducted to evaluate the clinical results of resection for retroperitoneal soft tissue sarcoma (STS) with vascular involvement. METHODS: The study group consisted of consecutive patients (mean age, 52 years) who underwent surgery for retroperitoneal STS with vascular involvement. The procedures were performed between 1988 and 2004. Vessel involvement by STS was classified as type I, artery and vein; type II, only artery; type III, only vein; and type IV, neither artery nor vein (excluded from the analysis). Patient data were prospectively gathered in a computerized database and retrospectively analyzed. RESULTS: Of 141 patients with retroperitoneal STS, 25 (17.7%) underwent surgery for tumors with vascular involvement. The most common vascular involvement pattern was vein only (type III) at 64%. Arterial and vein (type I) and arterial only (type II) involvement were observed in 16% and 20% of the cases, respectively. STS originating from the vessel wall (primary vessel involvement) was seen in eight patients, and 17 patients had secondary vascular involvement. Resection and vascular repair were done in 22 patients (no vascular repair in three patients due to ligation of the external iliac vein in one patient, and debulking procedures in two). All patients with arterial involvement (type I and II) had arterial reconstruction consisting of aortic replacement (Dacron, n = 3; and expanded polytetrafluoroethylene [ePTFE], n = 2), iliac repair (Dacron, n = 3), and truncal reimplantation (n = 1). The inferior vena cava (6 ePTFE tube grafts, 3 ePTFE patches, 2 venoplasties), iliac vein (1 ePTFE bypass, 1 Dacron bypass, 1 venous patch), and superior mesenteric vein (1 anastomosis, 1 Dacron bypass) were restored in 80% of the patients (n = 16) with either arterial and venous or only venous involvement (type I and type III setting). Morbidity was 36% (hemorrhage, others), and mortality was 4%. At a median follow-up of 19.3 months (interquartile range, 12.8 to 49.9 months) the arterial patency rate was 88.9%, and the venous patency rate was 93.8% (primary and secondary). Thrombosis developed in one arterial and venous (type I) iliac reconstruction due to a perforated sigmoid diverticulitis 12 months after surgery. The local control rate was 82.4%. The 2-year and 5-year survival rates were 90% and 66.7% after complete resection with tumor-free resection margins (n = 10 patients, median survival not reached at latest follow-up). The median survival was 21 months in patients with complete resection but positive resection margins (n = 7) and 8 months in patients with incomplete tumor clearance (n = 8, persistent local disease or metastasis). CONCLUSIONS: Patency rates and an acceptable surgical risk underline the value of en bloc resection of retroperitoneal STS together with involvement of blood vessels. The oncologic outcome is positive, especially after complete resection with tumor-free resection margins. A classification of vascular involvement can be used to plan resection and vascular replacement as well as to compare results among reports in a standardized fashion.