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Objectives: To present long-term results of endoleak/endograft migration treatment by aortomonoiliac (AMI) endografting after failed endovascular aneurysm repair (EVAR) of infrarenal abdominal aortic aneurysms., Design: Post hoc analysis of a prospectively gathered database at a tertiary care university hospital., Materials and Methods: From March 1995 to November 2010, 23 patients were identified who underwent modification into AMI configuration after failed elective EVAR. Major causes for modification were type I (with/without endograft migration) or type III endoleaks with aneurysm expansion. An average increase in aneurysm size of 1.6 cm (range: -1.5 to 10.5 cm) since initial aneurysm treatment was observed. Interventional outcomes and long-term results were recorded for analysis., Results: Technical success rate of AMI endografting was 95.65% (n = 22). All except two endoleaks could be successfully sealed with this manoeuvre (94.44%). Median time to modification was 5.3 years (interquartile range Q1-Q3: 1.3-9.3 years). No intra-operative conversion to open surgery was necessary and mortality was 0%. Median follow-up was 44 months (interquartile range Q1-Q3: 17-69 months)., Conclusions: Treatment of graft-related endoleaks/endograft migration by AMI endografting after failed EVAR represents a safe and feasible procedure. This approach broadens the minimal invasive opportunities of aneurysm treatment, and open surgical conversion may be avoided except in selected patients., (Copyright © 2012 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Two treatment options are available for abdominal aortic aneurysms (AAAs): open surgical technique with graft replacement and endovascular aortic aneurysm repair (EVAR) as a minimally invasive procedure. The intention of this review is to highlight the advantages of both procedures and to demonstrate that offering both procedures is beneficial for the patient when he or she makes the important decision regarding which treatment to select. A comparative evaluation of both treatment options is offered as well as a short description of the risk of rupture and its consequences. The authors discuss the latest literature as well as their own experiences. An innovative statistical approach-the propensity score-based Cox model-is presented to evaluate the 2 treatment options. The benefits of offering both EVAR and open surgery permit optimal management of AAA for the individual patient and tailor the treatment to his or her organ dysfunctions and impaired physical status. In addition, EVAR offers a treatment option for otherwise incurable high-risk patients.

Background: In this prospective randomized multicenter trial, knitted gelatine-coated Dacron, knitted collagen-coated Dacron, and stretch polytetrafluoroethylene (PTFE) aortic bifurcation grafts were compared for their long-term results., Methods: Between 1991 and 1998, 149 patients undergoing elective revascularization for aortoiliac occlusive disease were prospectively randomized at 3 tertiary referral centers of vascular surgery. The patients received either gelatine-coated Dacron (GEL-D) grafts (n = 52), collagen-coated Dacron (COL-D) grafts (n = 49), or stretch PTFE grafts (n = 48)., Results: No intraoperative deaths were recorded. The 30-day mortality was 4%. The mean follow-up time was 97 months. Primary patency rates were 77% for GEL-D, 78% for COL-D, and 79% for PTFE at 8 years. The differences were not different (P >.8). Secondary corrected 8-year patency rates were also not significantly different (P >.5): 91% for GEL-D, 96% for COL-Dm and 90% for PTFE. Five Dacron and 1 PTFE grafts were affected by infections., Conclusions: Bifurcation grafts for revascularization of aortoiliac occlusive disease using these 3 materials were comparable in terms of primary and secondary patency and long-term complication rates.

Background: A prospective randomized multicenter trial was performed to compare knitted gelatin-coated Dacron bifurcation grafts, knitted collagen-coated Dacron grafts, and stretch polytetrafluoroethylene (PTFE) grafts., Methods: Between 1991 and 1998, 315 elective patients were randomized by age, gender, diabetes, runoff, indication (aneurysm, aortoiliac occlusive disease), and nicotine consumption at 3 centers of vascular surgery in Austria. The patients received gelatin-coated Dacron (GEL-D) grafts (n = 109), collagen-coated Dacron (COL-D) grafts (n = 100), or stretch PTFE grafts (n = 106)., Results: No intraoperative deaths occurred. The 30-day mortality was 3%. No difference was found between the 3 graft materials in long-term patency. The primary 5-year patency rates were 92% for GEL-D, 89% for COL-D, and 91% for stretch PTFE (P =.6001). The secondary 5-year patency rates also differed: 97% for GEL-D, 100% for COL-D, and 97% for stretch PTFE (P =.2062). Early occlusions were observed overall in 3% and late occlusions in 5% of patients. When both Dacron grafts were compared collectively with stretch PTFE, a difference was found in infection rate: Dacron 3% (6/209) versus PTFE 0% (0/106); P <.03., Conclusions: The bifurcation grafts of all 3 materials were comparable in primary and secondary patency rates, incidence of false aneurysms, and rate of perioperative complications. Graft infections were confined to the 2 Dacron grafts and did not occur in stretch PTFE grafts.

Objectives: non-physiological flow behaviour plays a significant role in the development of distal anastomotic intimal hyperplasia. To investigate flow patterns in four anastomotic types of femoral end-to-side distal bypass graft anastomoses, a flow visualisation study was performed., Methods: transparent 1:1 casted replicas of distal vascular graft anastomoses created by conventional technique, Miller-cuff, Taylor- and Linton-patch were fabricated. A pulsatile mock circulation with a high-speed video system was constructed. Flow pattern was determined at mean Reynolds numbers 100-500. Migrations of the stagnation points on the bottom of the anastomoses at mean Reynolds numbers 100, 230, and 350 were measured., Results: a vortex forms during early systole and increases to maximum systole in all anastomoses. During the diastolic phase the vortex moves in the Miller-cuff distally to the toe of the anastomosis and remains standing, while in the other anastomotic types the vortex moves proximally to the heal of the junction and breaks down. The shift of the stagnation point in the Miller-cuff was considerably smaller than in the other anastomoses., Conclusion: conventional, Linton and Taylor anastomoses show similar flow patterns. The Miller-cuff with its wider cavity shows lower shift of the bottom stagnation point, but a persistent washout of the anastomotic cavity, which may contribute to its reported good clinical performance., (Copyright 1999 Harcourt Publishers Ltd.)

Objectives: To assess the early experience with the transfemorally placed modular endovascular MinTec graft (TPEG) for abdominal aortic aneurysm (AAA)., Design: One single centre prospective evaluation of the endograft procedure as well as early postoperative results., Setting: An academic teaching hospital., Patients: 30 consecutive patients treated during a period of 15 months., Results: Peri- and postoperative morbidity and mortality were evaluated according to the recommendations of the Ad Hoc Committee on Reporting Standards. The endograft procedure was successful in 28 patients (93.4%); two patients (6.6%) needed conversion into open conventional y-graft replacement; one patient died 36 days following intervention from multiple organ failure. Another patient died from pancreatitis unrelated to the implantation. Endoleaks were treated by "overstenting" or distal extension of the endografts, but conversions were unnecessary. Five severe adverse events were noted in four patients., Conclusions: TPEG is a feasible but technically demanding procedure, requiring both surgical techniques and catheter skills. The potential for less operative morbidity and simpler aneurysm management compared to conventional open surgery may be present. Close follow-up of patients is necessary to understand the development and treatment of endoleaks.

Purpose: To determine the rate of complications of transluminally placed endovascular stent-grafts in patients with abdominal aortic aneurysms and to assess efficacy of secondary radiologic intervention., Materials and Methods: In 28 patients, covered nitinol stents were implanted. Frequency and outcome of complications were evaluated after stent-graft placement (mean follow-up, 8.2 months)., Results: In 27 patients, 11 tube and 16 bifurcated grafts were implanted successfully. In one (4%) patient, distal migration of a bifurcated graft necessitated conversion to standard open repair. Technical success rates (successful deployment of the device and complete exclusion of the aneurysm at intraoperative angiography) for bifurcated and tube grafts were 24% (four of 17 patients) and 91% (10 of 11 patients). After surgery, leaks were seen in six bifurcated and five tube grafts. After secondary intervention, the final exclusion rate for bifurcated and tube grafts was 88% (15 of 17 patients) and 100% (11 of 11 patients), respectively; the overall success rate was 93% (26 of 28 patients) for exclusion of aortic abdominal aneurysms. Stent-graft thrombosis necessitated local thrombolysis in one patient. Overlapping of accessory renal arteries occurred in two patients., Conclusion: Complications after stent-graft placement in abdominal aortic aneurysms are frequent. Secondary radiologic intervention is successful in most cases.

Purpose: Our goal was to evaluate the value of maximum intensity projections (MIPs) rendered from spiral CT in the assessment of abdominal aortic aneurysms after stent graft implantation., Method: Spiral CT of the aorta was performed in 28 patients 1 week after implantation of covered aortic stent grafts. MIPs were evaluated in a blinded fashion. Transaxial scans and intravenous angiographs were considered the reference standard., Results: Stent deformity was evident on the MIPs in 5 cases and stent angulation was seen in 24 cases. The excluded aneurysmal sac was visualized in 14 (50%) cases. MIPs depicted the patent inferior mesenteric artery in 20 of 23 cases (87%). Renal artery occlusion (n = 3), leaks (n = 8), and parietal thrombi, (n = 3) were detected on the MIPs in all cases., Conclusion: MIPs are a valuable tool in the assessment of aortic stent grafts.

Background: The treatment of aortic aneurysms with endovascular stents or stent-graft prostheses is receiving increasing attention as an alternative to major abdominal surgery. To define the clinical value of this technique, we prospectively studied the use of stent-graft endoprostheses made of nitinol and covered with polyester fabric for the treatment of infrarenal abdominal aortic aneurysms., Methods: We treated a total of 154 patients at three academic hospitals. Twenty-one patients with aortic aneurysms not involving the aortic bifurcation received straight stent-grafts, and 133 patients with aortic aneurysms involving the bifurcation and the common iliac arteries received bifurcated stent-grafts. After a unilateral surgical arteriotomy, the endoprostheses were advanced through the femoral arteries and placed under fluoroscopic guidance. Computed tomography and intraarterial angiography were performed during an average follow-up of 12.5 months., Results: The primary success rate, defined as complete exclusion of the abdominal aortic aneurysm from the circulation, was 86 percent in the group receiving straight grafts and 87 percent in the group receiving bifurcated grafts. In three patients the procedure had to be converted to an open surgical operation. Minor (n=13) or major (n=3) complications associated with the procedure (including 1 death) occurred in 10 percent of the patients. All patients had a postimplantation syndrome, with leukocytosis and elevated C-reactive protein levels., Conclusions: Our results suggest that endovascular treatment of infrarenal abdominal aortic aneurysms is technically feasible and can effectively exclude abdominal aortic aneurysms from the circulation. With further refinement, endoluminal repair may emerge as an interventional strategy to treat infrarenal aortic aneurysms, especially in patients at high surgical risk.

Intraoperative angioscopic control was performed in an early series of 27 patients undergoing peripheral vascular surgery. The majority were complex or re-do operations; reversed saphenous vein and PTFE-grafts were used as bypass material exclusively. Angioscopic findings were compared to conventional angiography with respect to the detection of technical problems leading to further surgical procedures. Angioscopy was feasable in 92.5%, it failed twice due to irrigation problems, which was before we used a dedicated angioscopy roller-pump. In 6 patients relevant findings requiring further surgical manipulations were only detected angioscopically, in 2 patients such findings were detected by angioscopy as well as by angiography. Such findings included technical problems (graft rotation [n = 1], anastomotic narrowing [n = 2]), balloon catheter injuries after thromboembolectomy (n = 2) and residual thrombi after local thrombectomy (n = 3); 5 of these patients had undergone previous vascular procedures in the same operation field. After local correction (n = 5) or placement of a new bypass (n = 3) there was no early graft failure. This early angioscopic experience confirmed previous reports that satisfactory visualization and specific recognition of angiographically unsuspected problems after peripheral reconstructions can be obtained by intraoperative angioscopic control. This was seen very distinctively in more complex and re-do operations, which we see as the cases most needing routine angioscopic control.

Dilated and varicose veins constricted with a Dacron mesh tube were successfully used as arterial bypass grafts to avoid nonautogenous vascular prostheses. Mesh constriction has also been used to adapt the venous graft lumen to the diameters of grafted arteries. The influence of the external mesh on the wall elasticity of such venous grafts and the reactions of the host artery were not investigated. Elastic properties of mesh constricted autologous veins used as arterial grafts in femoropopliteal reconstructions, as well as consecutive formation of distal anastomotic intimal hyperplasia (DAIH), were investigated in this experiment. Twenty-four autologous venous grafts were implanted in 12 sheep. Grafts were left natural (Groups 1 and 3) or were constricted with an external Dacron mesh (Groups 2 and 4); their diameters were left unchanged (Groups 1 and 2) or were matched to the diameter of the host artery (Groups 3 and 4). Wall elasticity of the graft, distal anastomosis, and distal artery were measured by locally applied crystal transducers during surgery and follow-up. Formation and localization of DAIH was evaluated histomorphologically after a median of 8.3 months. Graft wall elasticity was found to be lower (54.6 vs. 147.9, P = 0.006) and overall DAIH was found to be higher in mesh tube grafts (49.42 vs. 20.8 microns, P = 0.001, Mann-Whitney U-test). No differences in elasticity and DAIH formation were observed between grafts with adapted and large diameters. Constriction of venous grafts by a Dacron mesh tube reduces graft wall elasticity and promotes formation of DAIH. To avoid such an increased mismatch in compliance while making use of the advantages of this method, the external mesh tube must not be brought close to the distal anastomotic area itself.

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.

Some surgeons feel that femoro-femoral suprapubic crossover bypass (FF) is the treatment of choice in unilateral artery disease, whereas others reserve this procedure for the rare high risk patient. Results and their evaluation seem to differ depending upon the indications and the patients elected for comparison. We analysed 57 consecutive patients, who received a FF-PTFE graft between 1977 and 1989 (age 48-95 years; male/female 47/10; preoperative clinical status [Fontaine Classification] St. II: 19%, St. III: 58%, St. IV: 23%; diabetics: 14; smokers: 40). The estimated cumulative primary and secondary patency according to the Kaplan-Meier method were 52 +/- 10% (three grafts at risk) and 63 +/- 10% (six grafts at risk), respectively at 5 years. There was no statistical difference in the secondary patency comparing patients with a good and bad run-off (Breslow, Mantel-Cox). The cumulative 5-year survival was 35 +/- 7% (nine patients at risk). The results were compared with those obtained in a group of 150 patients, in whom an unilateral ilio-femoral (IF) retroperitoneal orthotopic graft had been implanted for the same indication and within the same period. Comparing the primary patency of FF and IF patients (55 +/- 6%; 24 grafts at risk) no significant difference could be seen at 5 years. But there was a significant difference in the 5-year survival rates, being in favour of the IF-group (43 +/- 5%; 43 patients at risk) suggesting that both groups were not comparable.(ABSTRACT TRUNCATED AT 250 WORDS)

During the past 2 years (April 1981-March 1983) 50 PTFE Y-grafts were implanted. The early results are good. Except one graft limb occlusion (8 months postoperatively), which was successfully managed by thrombectomy, all grafts are functioning well or did so until death. 5 patients (age 70-84 years, aortic aneurysm, additional vascular surgery) died 1 day to 8 weeks postoperatively. The death was not specifically related to the material of the new prosthesis. Advantages of PTFE are: a) no need of preclotting; b) absolute tight body of the prosthesis even in the heparinized patient; c) thrombectomy is easy to perform. Important technical details, mandatory for a safe operative procedure and for good functional as well as morphological results, are reported.

21 patients had aortoiliac reconstructions for aortic aneurysms or occlusive disease with the new PTFE Y-graft during the past 12 months. 2 patients in the aneurysm group with additional renal artery reconstruction suffered postoperative myocardial infarction and subsequently died. 2 patients older than 80 years died after aneurysm repair in cause of graft infection, respectively respiratory insufficiency. All grafts (n=17) are functioning well or did so until death of the patient (n=4). The obvious advantage of the PTFE Y-graft is the fact, that there is no need of preclotting. Suture line--even using 4-0 material at the proximal anastomosis--and graft body is absolutely tight and no blood loss has to be expected from this site. However positioning of the left limb of the y-graft can be difficult in patients with right sided extraperitoneal approach and proximal side end anastomosis. Performing an end-end anastomosis can overcome this problem. For occlusion of the prosthesis limbs two vascular clamps on each side are needed to control blood flow within the rather stiff graft. Immediate and short term function is excellent. There was no material specific complication noted until now. Further longterm experience is necessary to evaluate the definitive quality of this new prosthetic material after some years.

Sonography should be routinely used for clinical follow up of patients with prosthetic grafts replacing the abdominal aorta and iliac vessels. 112 patients were investigated and the normal findings as well as pathological changes following aortic graft implantation are described and the difference between Dacron and PTFE-Y graft material discussed. Adequate visualization of anatomic detail of the graft was found in 82.1%. In the remaining patients the site of implantation was partly or completely overshadowed by bowel gas. 67.4% showed normal graft findings, whilst the remaining 32.6% exhibited incipient or manifest minor or major pathological changes such as dilatation of graft material, kinking, pseudoaneurysm, intraluminal thrombotic material and occlusion of parts of the implanted grafts. Dilatation was seen only with Dacron grafts and kinking only with PTFE-Y graft material. In combination with the clinical findings sonography helps to reduce the necessity of invasive angiographic procedures and allows early recognition of abnormal anatomical situations.

39 Sparks-Mandril grown grafts were implanted as arterial substitute in the femoropopliteal region and followed up for a minimum of 36 and a maximum of 57 months. At 7 instances it was not possible to perform the connecting procedure, 18.7% immediate occlusions, 28.2% early failures within the first postoperative year, 12.5% pseudoaneurysmal changes were noted. 13 patients (40.6%) demonstrated function for more than one year. Dilatation, elongation and parietal thrombosis over the whole length of the graft (2 cases) and late reocclusion turned out to be the main problems. Only 2 patients carry a properly functioning graft.

A randomized prospective study comparing PTFE-Y and Dacron-Y-grafts with regard to function rate, morphology, hemodynamic differences along the proximal anastomosis and body of the graft, complications and quality of material was performed. Between March 1983 and February 1987, 112 patients were admitted to the study. Randomization including the criteria of age, sex, indication to operation (chronic occlusive disease, aneurysm) run-off, diabetes, nicotine consumption and operative approach (transperitoneal, retroextraperitoneal) followed the methods of adaptive randomization developed by Pocock and Simon and was well balanced. Function rate and complications as well as morphological alterations showed no significant differences in either group. During a mean observation period of 24 months, Group I yielded a 97% and Group II a 95% function rate (Kaplan-Meier). In all patients but one in each group with limb graft occlusions (n = 5) function was regained by successful thrombectomy and profundaplasty. With respect to Doppler ultrasound differences in flow pattern, in four patients with enlarged proximal side-end anastomosis and adequate--not to large--incision is recommended performing the proximal anastomosis.

The intraoperative angiography was employed in 307 vascular reconstructive procedures (thrombendarterectomies (TEA) n = 107 = 34.8%; Veinbypass (VBP) n = 145 = 47.2%; fabric grafts (KBP) n = 44 = 14.4%) within the femoro-popliteal and crural region. 11.7% unsuspected technical errors were detected (TEA 18.6%, VBP 8.2%; KBP:6.8%) by angiography and successfully revised prior to wound closure. Errors were most common after thrombendarterectomies followed by VBP and KBP. Revisions after immediate failures were performed successfully in 7.4% (TEA : 8.4%, VBP: 5.5%, KBP: 6.8%). Lesions on X-ray of questionable significance were accepted in 6.8%, and followed by 4 immediate occlusions (1.7%). In 3.6% of the angiogramms the film was not satisfactorily exposed from the technical point of view. We think intraoperative angiography is a valuable adjunct in peripheral vascular surgery helping to detect and correct technical errors.

In a high risk patient an extended extraanatomic PTFE (ring armored) bypass was performed for limb salvage. The right subclavian artery served as donor vessel to the left tibial anterior artery in a crossover suprapubic fashion. A total of 7 anastomoses in this subclavian bifemoro-crossover popliteo-crural reconstruction yielded a high flow situation as well as good function with a palpable dorsalis pedis artery pulse and a postoperatively increased ankle-brachial pressure index of 0.9, 8 months postoperatively. During the 9th postoperative month the distal part of the reconstruction occluded and the left leg was amputated below the knee. However, limb salvage was achieved for 9 months. Several points are discussed in connection with long-term functioning.

Unilateral iliac femoral reconstructions with PTFE are yielding good results-similar to those with Dacron, with patency rates of 75, 67, and 65% at 1, 2 and 3 years, respectively (Kaplan-Meier). PTFE has additional advantages compared with other materials: a) no need of preclotting; b) smooth inner surface-easy thrombectomy in case of thrombosis and c) good handling characteristics. In view of the above-mentioned facts PTFE can be recommended without restriction for unilateral pelvic reconstructions. The functional early results of bilateral aorto-femoral Goretex-Y bifurcation grafts in 50 cases after 2 years are encouraging. Long-term results are still pending. Reports of other groups using this material as aorto-bifemoral substitute are not yet available. The functional results with PTFE for femoro-popliteal grafts are not satisfactory: 35% after 2.5 years. Extra-anatomical bypasses yielded 70% one-year functioning rate. Especially the ring-or spiral-armoured PTFE grafts seem to be suitable for these reconstruction procedures.