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PURPOSE To investigate the theoretical forces involved in and the nature of fixation between the modular components of a variety of aortic stent-grafts. METHODS An in vitro study of 6 aortic stent-grafts was performed using a tensometer. The modular stent-graft components were distracted until the iliac limb was completely separated from the main body. Tests were repeated at least 6 times for each stent-graft. RESULTS The maximum pullout force was 36.0 N using the Fortron stent-graft, which resulted in stent-graft disintegration. The maximum median forces of the other stent-grafts were 23.7 N (19.9-31.2) for the Aorfix, 7.3 N (6.9-7.6) for the AneuRx, 7.0 N (6.8-7.1) for the Zenith BiFab, 5.4 N (5.0-6.5) for the Talent, and 2.4 N (2.2-2.4) for the Vanguard II CONCLUSION: The results of this in vitro study suggest that current forms of iliac limb fixation in modular aortic stent-grafts are adequate provided the components are deployed with sufficient overlap. However, for many of the stent-grafts tested, the safety margin was small.

Purpose: To determine in a retrospective analysis the incidence of renal impairment (RI) following endovascular repair (EVR) of abdominal aortic aneurysm (AAA), to assess the morbidity and mortality in endograft patients with preoperative RI, and to examine the impact of suprarenal stent-grafts on renal function. Methods: From March 1994 to October 2001, 315 AAA patients (289 men; mean age 72.4±7.0 years) undergoing EVR were entered prospectively into a vascular registry. The patients received either an in-house custom-made stent-graft or one of several commercially made devices implanted with infrarenal or suprarenal fixation. Renal function was monitored by serum creatinine measurements prior to discharge and at 3, 6, and 12 months and annually thereafter. Preoperative RI was defined as a serum creatinine > 130 μmol/L and/or long-term dialysis. Postoperative RI referred to a >20% increase in the serum creatinine over baseline. Additional deterioration of renal function in patients with preoperative RI was referred to as postoperatively worsened RI. Results: Of the 315 patients treated, 220 (69.8%) were considered high risk (ruptured AAA or ASA grade III or IV). Sixty-nine (21.9%) patients had preoperative RI (6 [1.9%] on preoperative dialysis). A suprarenal stent-graft was used in 169 (53.7%) patients and infrarenal stent-graft in the remaining 146 (46.3%). The mean follow-up was 30.1 ±22.7 months. Postoperative RI occurred in 53 (16.8%) patients (24 [7.6%] transient, 29 [9.2%] persistent). Patients with preoperative RI had a significantly higher incidence of postoperatively worsened RI (37.7% versus 11.0%, pConclusions: Endovascular AAA repair may lead to persistent postoperative RI in nearly 10% of cases, especially in patients with preoperative RI. Suprarenal stent-graft fixation does not seem to have any deleterious effect on renal function. Further long-term studies are required to confirm the innocuous nature of transrenal stent placement.

Purpose: To investigate the feasibility, efficacy, and long-term effects of peri-aortic ligatures and Palmaz stenting used to treat proximal type I endoleak after endovascular repair (EVR) of abdominal aortic aneurysm (AAA). Methods: An 8-year single-center experience with proximal type I endoleak was reviewed; the records of the 55 identified cases were examined to ascertain the methods of treatment used. Among these, all 22 patients who were treated with peri-aortic ligatures and Palmaz stenting were segregated for analysis. Results: The 22 patients (14 men; mean age 74.6 years, range 66–85) with proximal type I endoleak (18 early, 4 late) selected for analysis underwent 23 secondary procedures: 15 involving peri-aortic ligatures and 8 Palmaz stent implantations. Of the 18 early endoleaks, 11 were treated intraoperatively and 7 were observed. Ten (45%) patients died within 30 days of endoleak treatment: 8 had early endoleaks. Five of the 10 deaths occurred in patients successfully treated with peri-aortic ligatures (3/10) or Palmaz stenting (2/7). The 12 (54%) surviving patients suffered no aneurysm-related deaths or secondary endoleaks over a median follow-up of 20 months (range 4–75) Conclusions: Endoleak is an important mode of failure after endovascular repair. Peri-aortic ligatures and Palmaz stenting are feasible techniques for the treatment of proximal endoleak; however, the perioperative mortality of peri-aortic ligatures was higher when compared with other less invasive techniques. In contrast to other therapeutic options, these methods are more effective in the short and medium term.

Endovascular aneurysm repair (EVAR) is a controversial technique, which remains the subject of a number of prospective randomised trials. Although questions remain regarding its long-term durability objective evidence exists which demonstrates its reduced physiological impact compared with conventional open repair. If this technique could be used in patients with ruptured abdominal aortic aneurysm (AAA) it may reduce the high peri-operative mortality. A review of the literature identified a limited experience with EVAR of ruptured AAA. Only a small number of case series with selected patients exist. The majority of patients were haemodynamically stable. However, the selective use of aortic occlusion balloons allowed successful endovascular management in a small number of unstable cases. All investigators had access to an “off the shelf” endovascular stent-graft (EVG). Per-operative mortality ranged from 9 to 45% and may reflect increasing experience and patient selection. A number of patients who underwent successful EVAR were turned down for open repair. A number of important lessons have been learned from these studies but questions remain regarding patient suitability and staffing issues. If these difficulties can be surmounted then the technique may offer an alternative to open repair. Eur J Vasc Endovasc Surg 25, 191–201 (2003)

Objective: Endovascular repair (EVR) of abdominal aortic aneurysm (AAA) is being performed with increasing frequency worldwide. No studies have a complete follow-up of more than 4 years. Our study objective was to assess the long-term results and the durability of a first-generation stent graft with complete 7-year follow-up. Methods: Between March 1994 and May 1995, 23 consecutive patients underwent treatment with the Chuter stent graft at a single center. All patients underwent computed tomographic scan before discharge, at 3 and 6 months, and annually thereafter. The data were prospectively collected on all patients. The median follow-up period was 72.5 months (range, 0.2 to 91 months). None of the patients were lost to follow-up. Results: Among these 21 men and two women with a median age of 69 years (range, 52 to 85 years), 11 (47.8%) were at high risk. The 30-day technical success rate was 87%. Acute (30-day) complications were one graft deployment failure (4.3%) that necessitated an immediate conversion, 20 intraoperative graft limb kinks (87%), all of which needed additional Wallstent (Schneider, Minneapolis, Minn) placement, four renal failures (17.4%), one type Ia endoleak complicated with AAA rupture (4.3%), and three perioperative deaths (13%). Late complications were eight type I or II endoleaks (34.8%) after a mean delay of 23.9 months (range, 3 to 69 months), 13 proximal stent migrations (56.5%) after a mean delay of 29.6 months (range, 7 to 58 months), six graft limb thromboses (26.1%) after a mean delay of 38.7 months (range, 3 to 71 months), one AAA rupture (4.3%), and 11 deaths (47.8%), with five AAA-related deaths (21.7%). The 3-year, 5-year, and 7-year cumulative endoleak rates were 34%, 41%, and 49%, respectively; the cumulative migration rates were 66%, 75%, and 75%, respectively; and the cumulative open surgery rates were 30%, 50%, and 50%, respectively. At the same intervals, the cumulative survival rates for any death were 69%, 56%, and 49%, respectively; the cumulative survival rates for AAA-related deaths were 82%, 82%, and 73%, respectively; and the cumulative secondary success rates were 54%, 28%, and 28%, respectively. Conclusion: This studies emphasizes the need for close lifelong surveillance of AAAs treated with EVR. Despite the small population of this series, a long-term follow-up highlights that the first-generation homemade stent graft evaluated in this study failed to adequately protect the patient from AAA-related death and that most of the serious complications were related to a late failure of the aortic neck attachment. Better proximal fixation of the aortic stent graft is essential to improve the durability of EVR. (J Vasc Surg 2003;37:367-73.)

Purpose: To evaluate the efficacy and midterm results of the Zenith stent-graft in the treatment of abdominal aortic aneurysms (AAA). Methods: Since March 1994, 364 patients have undergone endovascular repair of infrarenal AAA. Of the 94 who were treated with the Zenith stent-graft from 1996 to 2002, 88 patients (82 men; mean age 72.6 ± 6.5 years, range 47–88) with at least 6-month follow-up were analyzed. Sixty-one (69.3%) patients were considered at high risk for intervention; 7 ruptured AAAs were treated emergently. In all, 68 (77.3%) bifurcated stent-grafts (including 18 TriFab systems) and 20 aortomonoiliac configurations were used. Cumulative data on endoleak, migration, secondary procedures, and survival were evaluated with Kaplan-Meier analyses. Results: Implantation success was 97.7%; 2 (2.3%) access-related failures were converted to open repair (1 immediate, 1 at 3 months). There were 3 (3.4%) graft limb thromboses (2 immediate, 1 late), 3 (3.4%) cases of colon ischemia due to embolization in 1 and hypogastric artery occlusion in 2, and 1 (1.1%) renal infarction due to embolism. Three (3.4%) patients died within 30 days. Eleven (12.5%) endoleaks and 1 (1.1%) late endograft migration were recorded. The 5-year cumulative endoleak and migration rates were 15% and 7%, respectively. Sixty-three (71.6%) patients did not present any complication related to the repair during a mean follow-up of 20.6 ± 14.9 months (range 6–68); notably, no complications were associated with the 18 TriFab systems. Six (6.8%) secondary procedures were performed (31% 5-year cumulative secondary procedural rate). All 6 (6.8%) aneurysm-related deaths (the 3 perioperative, 2 from late AAA rupture, and 1 during a secondary procedure) and 14 of 18 (20.4%) non-aneurysm—related deaths occurred in high-risk patients; the 5-year cumulative survival rates were 57% for any death and 92% for aneurysm-related deaths. Conclusions: The Zenith stent-graft appears both safe and effective in terms of midterm outcome of endovascular aortic aneurysm repair.

Purpose: To demonstrate aneurysm sac expansion in the face of a type II endoleak and its treatment with open ligation of multiple side branch endoleaks. Case Report: An 81-year-old patient had undergone elective endovascular repair of a 6.3-cm infrarenal abdominal aortic aneurysm in September 1999. Routine spiral computed tomographic angiography at 10 months disclosed a type II endoleak; the aneurysm sac diameter had grown to 7.4 cm. Selective angiography revealed multiple lumbar endoleaks and a patent inferior mesenteric artery. Laparotomy and sacotomy was performed, confirming the presence of pulsatile type II endoleaks, which were ligated successfully. The patient made a full postoperative recovery. Conclusions: Type II endoleaks may cause aneurysm expansion. Open repair of multiple type II endoleaks is feasible and may be useful where endovascular or laparoscopic techniques are at high risk of procedural failure, such as multiple endoleak channels.

Purpose: To demonstrate the feasibility of a hybrid endovascular procedure to preserve blood flow in the internal iliac arteries (IIA) during aortoiliac endografting. Technique: When aneurysmal dilatation makes the distal neck in the common iliac artery (CIA) too short for an adequate seal, the CIA bifurcation is exposed via an extraperitoneal approach after endograft deployment. Via an arteriotomy in the CIA, the distal end of the stent-graft is sutured to the CIA bifurcation under direct vision to preserve IIA blood flow. This approach has been successful in preserving IIA blood flow in 5 of 7 endograft procedures; in the other 2, IIA occlusion was a predictable event. Conclusions: Direct suturing of an aortoiliac stent-graft to the CIA bifurcation via an extraperitoneal approach is a useful method of maintaining IIA perfusion. However, further study is required to identify patients at high risk of pelvic ischemia who would benefit from such intervention.

Purpose: To report a case of colonic infarction following endovascular abdominal aortic aneurysm (AAA) repair in a patient with both internal iliac arteries (IIA) unobstructed by the endograft. Case Report: A 73-year-old man presented with blue toes as a result of emboli from a 6.4-cm AAA. As he was medically at high risk for open repair and his aneurysm morphology was suitable for a modular bifurcated endovascular graft, a Zenith endograft was used to exclude the aneurysm. Twenty hours after the successful procedure, in which both IIAs were preserved, the patient regurgitated coffee-ground vomit; an upper gastrointestinal endoscopy found a small Mallory-Weiss tear and antral gastritis. A proton-pump inhibitor was begun, but his symptoms progressed. Laparotomy revealed transmural ischemia and infarction of the upper rectum, sigmoid, descending colon, and the splenic flexure; a colonic resection with formation of Hartmann's pouch and colostomy was performed. He made a slow but uncomplicated recovery. Conclusions: Colonic necrosis can complicate endovascular AAA repair even when both IIAs are preserved. Advantageously, the clinical signs of severe colonic ischemia in endograft patients are not obscured by aftereffects of a laparotomy.

Purpose: To report a single-center experience with endovascular repair of inflammatory abdominal aortic aneurysm (IAAA), with particular attention to the fate of the aneurysm sac, perianeurysmal fibrosis (PAF), and renal function. Methods: A retrospective review of 350 patients undergoing endovascular aortic aneurysm repair during a 7-year period at University Hospital, Nottingham, identified 14 (4%) cases of IAAA confirmed either on preoperative spiral computed tomography (CT) or at laparotomy in attempted open aneurysm repair. All data were reviewed from a prospectively maintained database, hospital notes, and serial CT studies. Results: Endovascular repair was successfully completed in all 14 IAAA patients, but 2 (14%) died in the perioperative period. One patient referred from another center was lost to imaging follow-up, leaving 11 patients who were followed for a mean 29 months (range 1–73). All 11 IAAAs remained excluded, but 1 patient required a secondary transabdominal intervention for a type III endoleak. There was no CT evidence of PAF progression in any patient. Postoperative renal complications were not encountered where there had been none preoperatively. Conclusions: IAAA may be successfully excluded by the endovascular technique, and EVAR is particularly useful where open repair has failed. The impact of endograft placement on perianeurysmal fibrosis is less clear. In this study, there was no suggestion that the degree of PAF worsens following endovascular repair.

Introduction: the mortality from ruptured abdominal aortic aneurysm (AAA) remains in the region of 50% despite advances in critical care. Endovascular repair of AAA has been shown to be associated with reduced physiological stress in the elective setting. It is hypothesised that the reduced physiological stress associated with EVAR may improve the outcome in patients with ruptured AAA. Methods: a feasibility study of endovascular repair of ruptured AAA was undertaken at the University Hospital, Nottingham, U.K. between 1994 and 2000. Patients admitted with ruptured AAA were assessed by a team familiar with endovascular techniques for elective repair of AAA. After giving informed consent patients underwent spiral computed tomographic angiography (CTA) in the majority of cases. Patients were then transferred to the operating theatre for EVAR. Results: twenty patients underwent repair of ruptured AAA. Of these 20 patients, seven were referred from another hospital. Eight patients were considered unfit for open repair. The median duration of procedure was 180 min (range 120–480) and median blood loss was 1200 ml (range 750–2000 ml). The overall peri-operative mortality was 45%. A number of intra-operative and peri-operative procedures (both open and endovascular) were required to ensure aneurysm exclusion and to deal with the complications of endovascular surgery. Conclusions: ruptured AAA remains a particularly hazardous condition to treat. There are a number of advantages of EVAR in this condition. A number of the problems early in the experience of EVAR have been addressed, but further experience is required to demonstrate its efficacy when compared with open repair.

Purpose: To report an experience using intrarenal color duplex ultrasonography (ICDU) to detect high-grade renal artery stenosis in patients who had endovascular repair of abdominal aortic aneurysm (AAA) with suprarenal stent fixation. Methods: Twenty-eight patients (25 men; mean age 71 years, range 58–83) who had endovascular AAA repair with suprarenal stenting at least 3 months prior to commencement of this study were screened with ICDU. Acceleration time (AT), peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI) were measured. The Doppler waveform was quantitatively scored on a scale from 0 to 4. AT >0.07 seconds, RI Results: Median follow-up was 15.5 months (range 3–34). ICDU was successful in 54 (98%) of 55 kidneys scanned. No AT values exceeded 0.07 seconds, all RIs were >0.45, and no waveforms had loss of early systolic peak, indicating that no patient had evidence of high-grade renal artery stenosis. Conclusions: ICDU is a simple and affordable method that seems well suited to periodic screening in patients with suprarenal stents. Longer follow-up with a larger number of patients is needed before definite conclusions can be drawn about the effect of suprarenal stenting on renal circulation.

Objective to design a flow model to determine whether and why increased proximal neck angulation correlates with increased risk of proximal perigraft endoleak (PPE) flow. Methods a tapered stent-graft (Gianturco stent + Dacron) was deployed with proximal and distal necks made of silicone. The amount of PPE was measured over 30-s periods while the angulation of the proximal neck was increased. Results PPE flow increased significantly for angulations ≥30°. The graft was lifted off the neck wall and gaps between the stent-graft and the neck created. Conclusion greater neck angulation increased PPE flow. The stent-graft was lifted off the neck and subsequent gaps created. This model could be used to compare available stent-grafts and to test new designs that would improve the seal in angulated necks.

Purpose: To evaluate the initial and mid-term results of the Zenith endovascular grafting system for infrarenal abdominal aortic aneurysms. Methods: Prospective databases at seven centers were used to assess a cohort of patients that underwent treatment for aortic, aortoiliac, or iliac aneurysms since 1995. Data were analyzed to yield descriptive characteristics that pertained to the patients, the aortic morphologic features, the graft configuration, and the complications. Follow-up imaging data were used to determine size changes of the aneurysm sac, endoleak rates, and further complications. Finally survival data were expressed with a Kaplan-Meier analysis. Results: A total of 528 patients were treated with the Zenith endograft. Most of the patients (66%) were considered to be at a high physiologic risk for open repair. Successful graft implantation was accomplished in all but four patients. An overall endoleak rate of 15% was noted, of which 4% was treated urgently because they were thought to represent attachment site faults. The mean follow-up period was 18 months. A total of eight endograft migrations were detected after 2 years of follow-up with an early version of the system. There were three late conversions; two ruptures occurred during the follow-up period. Conclusion: This early and mid-term data support the use of the Zenith endovascular graft for the treatment of aortic and aortoiliac aneurysms in properly selected patients. The risks of significant complications or aneurysm rupture are low. (J Vasc Surg 2001;33:S157-64.)

Objectives: to establish the feasibility of using magnetic resonance imaging (MRI) with dynamic contrast-enhanced (DCE) MRA as the sole imaging modality in the assessment of patients prior to endovascular repair of abdominal aortic aneurysms (AAAs). Design: DCE MRA with MRI and helical computed tomography (CT) examinations were performed in patients being assessed for suitability for an endovascular approach to repair of their AAA. Management outcomes determined by the two techniques were compared. Materials: sixteen patients with AAA. Methods: all subjects underwent DCE MRA/MRI and helical CTA. Criteria for suitability for endovascular repair were established. The management outcomes determined by the MRI findings were compared with those obtained by CTA. Results: high-quality MRA/MRI and CT images were obtained in 16 patients. Six patients were considered suitable for an endovascular approach, one was considered borderline and nine were judged unsuitable. In all cases, the overall management determined by the two methods concurred. Conclusions: comparison of the two imaging modalities resulted in agreement as to suitability for an endovascular approach. We therefore conclude that in our group the use of MRI and DCE-MRA proved effective as a sole imaging modality for the assessment of these patients.

Purpose: To report a technique that might decrease the incidence of lumbar artery endoleaks following endovascular repair (EVR) of abdominal aortic aneurysms (AAAs). Methods: Ninety-three patients (86 males, median age 72 years, range 56 to 88) undergoing EVR with the aortomonoiliac technique were entered into a study to detect and then occlude patent side branches before completion of the endografting procedure. Prior to deploying the iliac occluder, an aneurysmogram was performed to detect patent aortic side branches. If these side branches were found, an absorbable gelatin sponge was inserted into the aneurysm sac via the occluder introducer sheath. The patients were followed with contrast-enhanced spiral computed tomography (CT) at 1 week and 3, 6, and 12 months to detect the presence of endoleaks. Results: Forty-eight (52%) patients demonstrated patent side branches that were occluded by the insertion of gelatin sponges into the aneurysm sac. The remaining 45 patients without evidence of side branch flow were untreated. Ten (10.7%) patients died in the perioperative period, and 15 (16.1%) primary endoleaks (13 proximal, 2 distal) were detected. This left 68 (73.1%) patients for follow-up, 33 (48.5%) of whom had patent branch vessels treated with the thrombogenic sponge. The median follow-up was 4 months (range 1 to 17), during which time no side branch endoleak was detected on surveillance CT scans in any of the 68 patients, which included all patients treated with the thrombogenic sponge technique and those in whom no patent side branches had been identified. Conclusions: We have demonstrated a safe and reliable method of preventing lumbar artery endoleaks following endovascular AAA repair.

Purpose: To present the perioperative and late mortality following endovascular repair (EVR) of abdominal aortic aneurysms (AAAs). Methods: Data were collected prospectively on 221 patients undergoing AAA EVR over a 4-year period (median 5-month follow-up). Patients were classified preoperatively as high risk with at least 1 of these features: serum creatinine > 150 μmol/L, ischemic heart disease or poor left ventricular function, respiratory function < 50% of predicted normal, ruptured or symptomatic AAA, contraindication to or failed open repair, and age > 80 years. Results: One hundred forty (63.3%) patients were classified as high risk, the most common criterion being cardiac disease (n = 96, 68.6%). There were 25 (11.3%) deaths in the 30-day perioperative period, 22 (15.7%) in the high-risk group compared to 3 (3.7%) in the acceptable-risk group (p = 0.02). The most common causes of perioperative death were multisystem organ failure and myocardial infarction. A further 21 (9.5%) late deaths occurred, 16 (11.4%) in the high-risk group and 5 (6.2%) in the acceptable-risk group (p > 0.1). Conclusions: The mortality of patients at acceptable risk undergoing EVR compares with the best published series for conventional open AAA repair. The perioperative and late mortality in the high-risk patients are substantially higher.

Objective: The purpose of this study was to detect any change in the proximal neck diameter after endovascular repair of abdominal aortic aneurysm. Methods: The study was performed in a teaching hospital with an endovascular program on 112 patients who had undergone endovascular repair of abdominal aortic aneurysm. The interventions were pre-endovascular and postendovascular repair of abdominal aortic aneurysms with contrast-enhanced, spiral computerized tomography, and the main outcome measures were change in aortic proximal neck diameter, change in maximum aortic diameter, presence of endoleaks, and change in length from lowest renal artery to aortic bifurcation. Results: The median anterior-posterior and transverse diameter decreased from 63.5 mm before surgery to 50.4 and 54.5 mm, respectively, after surgery in a period of 4 years. This trend in reduction in maximum diameter was not seen in the patients with endoleaks. There was no significant change in the proximal neck diameters when measured at 5-mm intervals after endovascular repair. There was also no significant change in the aortic length after endovascular repair. Conclusion: We have not demonstrated any evidence for proximal neck dilatation after endovascular repair of abdominal aortic aneurysm. (J Vasc Surg 1999;29:625-30.)

Purpose: To investigate the renal complications associated with endovascular repair of abdominal aortic aneurysms (AAAs). Methods: Data were prospectively collected on 164 AAA patients (154 males; median age 72 years; interquartile range 51 to 88) undergoing endovascular grafting. Any history of renal failure and diabetes mellitus was recorded. Serum urea and creatinine levels were measured preoperatively and at regular intervals postoperatively. Renal impairment was defined as serum creatinine > 130 μmol/L. Results: There were no significant differences in pre- and 1-day postoperative serum urea and creatinine levels. Among 15 (9.1%) patients with preoperative renal failure, 7 (47%) died, 4 (27%) in the perioperative period. Of the 149 patients with normal renal function preoperatively, 4 (2.7%) developed renal failure as part of multisystem organ failure. Another 9 (6.2%) developed significant postoperative elevations (> 20%) in their creatinine levels compared to baseline; 4 of these patients died, 2 in the perioperative period. There was no significant difference in the median dose of intravascular contrast used for those patients that did and did not have a deterioration in their renal function (250 mL versus 300 mL). Conclusions: In this study, approximately 6% of patients with normal preoperative renal function who undergo endovascular AAA repair develop renal dysfunction. For patients with preoperative renal impairment, the perioperative mortality rate is high, 27%, following endovascular aortic aneurysm repair.

Objective: Endovascular repair (EVR) of abdominal aortic aneurysm (AAA) has many potential advantages, one of which may be reduced blood product requirements. The aim of this study was to compare the current blood product usage in our unit for three types of elective operation: EVR of AAA, open AAA repair and femorofemoral crossover grafts. Design: Prospective data analysis with historical controls. Materials: One-hundred and thirty-two patients undergoing elective EVR of AAA, 35 patients undergoing elective open repair of AAA and 37 patients having femorofemoral crossover grafts. Methods: Data was collected on the blood product requirements of patients having EVR of AAA, with open AAA repair and femorofemoral crossover graft providing historical controls. Results: There was no difference in the haematological parameters preoperatively between the three groups but postoperatively patients having EVR had a slightly lower haemoglobin than the open group (10.6 g/dl vs. 10.85 g/dl, p = 0.015). The number of patients who received blood transfusion in the EVR group was 82/132 (62%) and the open group 27/35 (77%), p = 0.4. Conclusion: Patients undergoing EVR of AAA require blood transfusion in the same numbers when compared to those undergoing open repair.

PURPOSE To compare measurements of aortoiliac length obtained with spiral computed tomographic angiography (CTA) and aortography in patients undergoing endovascular aneurysm repair. METHODS The distances from the lower-most renal artery to the aortic bifurcation and from the aortic bifurcation to the common iliac artery (CIA) bifurcation were measured using both CTA and aortography in 108 patients with abdominal aortic aneurysms. RESULTS The level of agreement between CTA and aortography was high, with 69% of aortic and 76% of iliac measurements within 1 cm and > 90% within 2 cm of each other. Mean differences were -0.35 +/- 1.20 cm and 0.25 +/- 1.10 cm, respectively, for aortic and iliac lengths. Aortography overestimated renal artery to aortic bifurcation length in comparison to CTA (p = 0.003), particularly in patients with large aneurysms (> 6.5 cm) and lumen diameters > 4.5 cm (p < 0.0001). Measurements of CIA length were shorter by aortography than CTA (p = 0.02). CONCLUSIONS There is a high level of agreement between CTA and aortography in the measurement of aortoiliac length, but aortography overestimates renal artery to aortic bifurcation length in patients with large-diameter aneurysms and wide aneurysm lumens. CTA is sufficiently accurate in the majority of cases to be used as the sole basis for the construction of endovascular grafts.

PURPOSE: To assess the effect of abdominal aortic aneurysm (AAA) size on overall aneurysm morphology with special attention to possible relationships among various anatomic variables that determine the feasibility of endovascular repair. METHODS: One hundred sixty-eight patients were assessed with spiral computed tomographic angiography to measure the length and diameter of the AAA, the proximal neck, and the common iliac arteries. Anatomic variables were correlated with aneurysm size using Spearman's rank order correlation coefficients (rS); comparisons among small, intermediate, and large aneurysms were made using the Chi-square test. RESULTS: Correlations between aneurysm size and the anatomic variables above were weak. The strongest association was between aneurysm size and aortic length (rS = 0.41, p 3 cm), and hence, unsuitable proximal necks were found in patients with aneurysms > 7 cm in diameter (chi 2 = 7.8, p < 0.01). CONCLUSIONS: Shortening and widening of the proximal neck seems to increase with aneurysm size but only after the aneurysm expands beyond 7 cm in diameter. Aneurysms with diameters in the 4.5- to 5.5-cm range are no more suitable for endovascular repair than those between 5.5 and 7 cm. The lack of any significant correlation between anatomic variables emphasizes the need for accurate preoperative assessment of the anatomy of each individual patient before endovascular repair.

Objectives: To determine the full range of aorto-iliac anatomy of patients with abdominal aortic aneurysms (AAAs) and thence the range of endovascular graft sizes required to deal with the majority of AAAs. Design: Analysis of preoperative spiral CT measurements Materials: One hundred and sixty-eight patients with AAAS Method: Multiplanar reconstruction measurements were taken of proximal aortic neck diameter and length, lowermost renal artery to the aortic bifurcation distance and length and diameter of common iliac arteries. Based on these measurements a range of graft sizes that would fit the majority of AAAs was determined. Results: Ranges of anatomical variables were as follows: proximal aortic neck diameter 18–30 mm, renal artery to aortic bifurcation distance 93–210 mm, common iliac artery length 13–108 mm, common iliac artery diameter 6–67 mm. Over 750 graft sizes would be required to cover all anatomical combinations using a one-piece aorto-uni-iliac graft. Conclusion: A wide variety of aorto-iliac anatomy exists in patients with AAAs. The large number of graft sizes required to deal with the majority of AAAs makes the production of one-piece endovascular grafts commercially impractical. A proposed two-piece modular graft would allow the majority of AAAs to be treated using only 16 graft sizes.

Purpose: The aim of this study was to evaluate the feasibility of endovascular aortic aneurysm repair with use of an aortouniiliac graft secured with self-expanding (Gianturco) stents. Methods: Thirty patients with a median age of 72 years (age range, 52 to 86 years) and aneurysm diameter of 6.0 cm (range, 4.0 to 9.0 cm) were treated with an aortouniiliac endovascular graft. Of these 30 procedures, 28 were carried out electively and two as emergencies for leaking aneurysm. Of the 30 patients, 21 (70%) were considered to be at high risk for open surgery. A modified Gianturco stent, Dacron graft, and Wallstent were used for these procedures. Results: Endovascular repair was successfully carried out in 25 of 30 (83.3%) patients. All these patients were mobile and had resumed a normal diet within 48 hours of the procedure. The overall 30-day mortality rate was two in 30 (6.6%), but it was one in 28 (3.5%) for the elective cases; all deaths occurred in the group at high risk for surgery. Other complications encountered within 30 days of procedure included myocardial infarction in one patient, pneumonia in two patients, homonymous quadrantanopia in one patient, and colonic ischemia in one patient, giving an overall morbidity rate of four in 30 (13.3%). At a median follow-up of 4 months (range, 1 to 13 months), 27 of 30 (90%) patients remain alive and well. Conclusion: Endovascular aortouniiliac repair of abdominal aortic aneurysm with Gianturco stent is feasible in both elective and emergency situations. It appears to be minimally traumatic, and the majority of patients deemed to be at high risk for open surgery can safely undergo endovascular repair. However, data on more patients with longer follow-up is required to determine its role in the management of abdominal aortic aneurysm. (J Vasc Surg 1997;25:165-72.)

Background Pulse-spray thrombolysis is a rapid technique for the treatment of limb ischaemia of recent onset. Early results have been published but the longer term results are not known. Methods This study consisted of a series of 100 legs with acute and subacute ischaemia treated using this method with a follow-up interval of up to 3 years. Eighty-three limbs were classified as Fontaine grade Ill or IV and 42 had a sensory or motor deficit. Sixty-seven limbs were treated with pulse spray alone and 33 had an additional low-dose infusion. In 71 cases an additional catheter-directed intervention was required. Results Median duration of lysis was 135 (range 35–1540) min and median dose of recombinant tissue plasminogen activator used was 18 (range 4–61) mg. Complete radiological patency was achieved in 79 limbs and the ankle: brachial pressure index improved from a median of 0 (range 0–0.8) to 0.8 (range 0–1.5) (P

We have examined whether or not endovascular insertion of a bifurcated aorto-iliac graft resulted in greater intraoperative haemodynamic and metabolic stability than that achieved during conventional open graft placement. We studied 20 patients prospectively during surgery for asymptomatic infra-renal aortic aneurysm. All patients received the same anaesthetic technique. Haemodynamic data were collected continuously using indwelling radial artery and pulmonary artery catheters, allowing calculation of mean arterial pressure (MAP), cardiac output (CO) and systemic vascular resistance (SVR). Blood samples were obtained for measurement of serum lactate concentrations. Variables were compared within each group before and after specific critical events, namely occlusion of femoral or aortic blood flow, or both, and sequential reperfusion of each lower limb. Patients undergoing open repair showed significant changes in CO, MAP and SVR related to aortic cross-clamping and lower limb reperfusion, and a significant increase in blood lactate concentration after distal tissue reperfusion. The only significant changes during endovascular repair were a transient increase in SVR secondary to application of the femoral artery clamps, and sequential decreases when each limb was reperfused. Endovascular aneurysm repair imposed significantly less intraoperative haemodynamic and metabolic stress on the patient compared with conventional open surgery.

Unlike coronary thrombolysis, the role of platelet activity in the outcome of local thrombolytic therapy for peripheral ischaemia is not well understood. In the present study ten patients undergoing local pulse spray thrombolysis (PST) with recombinant tissue-type plasminogen activator (rt-PA), six patients undergoing conventional infusion thrombolysis (CT) with rt-PA and another six patients undergoing arteriography with iopamidol were studied. Venous blood samples obtained before and after the procedure were analysed using a flow cytometric technique for detection of platelet activation after labelling platelets with VH10, a monoclonal antibody against P-selectin. In the present study no significant differences were observed in P-selectin expression before and after any of the procedures, except that P-selectin expression following ADP stimulation was reduced in patients who had received conventional thrombolysis. Unexpectedly, we observed relatively greater P-selectin expression, particularly after ADP stimulation, both before and following thrombolysis in ten patients in whom thrombolysis was successful compared with six patients in whom thrombolysis was unsuccessful. ADP-induced P-selectin expression on platelets may therefore be a useful predictor of outcome of peripheral intra-arterial thrombolysis.

Objectives:To compare the time required to achieve lysis with the pulse spray technique and the conventional slow continuous infusion technique.Design:Prospective randomised open Study.Methods:Eighteen patients suitable for intra-arterial thrombolytic therapy with conventional and pulse spray technique were randomised 1.1 to receive either pulse spray thrombolysis with 0.33 mg/ml rt-PA injected as a bolus of 0.2 ml or conventional thrombolysis with 0.05 mg/ml rt-PA infused at a rate of 10 ml/h.Results:The age, duration of symptoms, length of occlusion and prethrombolysis ankle brachial pressure index were comparable in the two groups. The median duration of thrombolytic therapy in the pulse spray group was 195 min (range 90–1260) compared to 1390 min (range 300–2400) in the Conventional group. The difference between the two groups was significant, p < 0.002 (Mann-Whitney test).Conclusions:Significantly shorter time is required to achieve local thrombolysis with pulse spray compared to the conventional infusion method.

Purpose: To report the successful repair of a ruptured pseudoaneurysm of the infrarenal abdominal aorta secondary to pancreatitis Case Report: A 47-year-old man was admitted with abdominal pain due to an acute exacerbation of chronic alcoholic pancreatitis. He was found to have an infrarenal abdominal aortic aneurysm, which was confirmed by spiral computed tomography (CT), but there had been no evidence of aneurysm formation on a scan performed 1 year previously. Persistent symptoms prompted a further CT scan 48 hours later; this revealed evidence of a ruptured infrarenal abdominal aortic pseudoaneurysm. The pseudoaneurysm was excluded using a Zenith aortomonoiliac endovascular graft. Recovery was uneventful, and the patient underwent pancreatic resection 6 months later. A duplex scan 10 months after endograft placement could not identify an aneurysm sac. Conclusions: In selected cases, endovascular repair provides a useful method of excluding ruptured aortic pseudoaneurysms due to pancreatitis. It allows hemorrhage control in a potentially infected operative field and permits elective pancreatic resection. Prolonged follow-up is mandatory to ensure there is no evidence of graft sepsis and that aneurysm exclusion is maintained.

To determine the intermediate-term results of intra-arterial thrombolysis, 127 consecutive patients receiving 129 courses of treatment were reviewed at a median follow-up of 3 years. At initial review, 30 days after treatment, thrombolysis was successful in 63 cases (49 per cent). Of these patients, 16 were lost to follow-up: 15 died without further vascular symptoms and one moved from the area. Some 35 patients were alive and asymptomatic, of whom 33 had either angiographic or clinical evidence of continued arterial patency. Symptomatic reocclusion occurred in 12 cases; a further two patients remained asymptomatic and reocclusion was detected at follow-up. Two of the 12 symptomatic patients required amputation. Estimated patency rates were 80 per cent at 1 year, 72 per cent at 2 years and 70 per cent at 3 years. The intermediate-term results in the 66 cases in which lysis was unsuccessful were worse, only 16 patients (24 per cent) surviving to follow-up with the treated limb intact. It is concluded that, if thrombolysis is successful at 30 days, the intermediate-term results are good.

SummaryIn peripheral thrombolysis adjuvant anti-platelet therapy may help to lyse otherwise resistant thrombus, thereby increasing the number of patients successfully treated and reducing the “time to lysis”. If continued after lysis it may help to prevent early rethrombosis. In this pilot study 21 patients undergoing peripheral thrombolysis with streptokinase were randomised to receive the thromboxane receptor antagonist sulotroban or placebo. The dose of sulotroban given was 2 mg/min (four patients), 4 mg/min (five patients) or 8 mg/min (four patients), eight patients received placebo. The clinical and laboratory effects of the treatment were monitored.Thrombolysis was achieved more quickly in patients receiving sulotroban, however, there was no difference between groups in the number of patients in whom recanalisation was achieved (six of eight receiving placebo and eight of 13 receiving sulotroban) or in the number of cases of early rethrombosis. During lysis there was an increase in plasma beta-thromboglobulin with similar levels being found in patients receiving sulotroban and streptokinase and those receiving streptokinase alone. No other major changes in platelet function during lysis were seen in patients receiving streptokinase alone. Sulotroban significantly reduced platelet aggregtion and 14C-5HT release in response to several platelet agonists. With the thromboxane mimetic U46619 the degree of inhibition of aggregation and 14C-5HT release depended on the dose of sulotroban used. High levels of inhibition were associated with an excess of haemorrhagic complications especially in combination with a low plasma fibrinogen level.We conclude that the use of low dose sulotroban in combination with streptokinase merits further study and may have a role in accelerating lysis. However, the combination of high dose sulotroban with streptokinase causes an increased incidence of bleeding. Monitoring platelet function during such therapy may identify patients likely to bleed.

To present performance data on the use of the Aorfix stent-graft in patients with hostile infrarenal abdominal aortic aneurysm (AAA) anatomy.A study protocol was designed to examine the safety and efficacy of the Aorfix endovascular stent-graft in AAA patients who had a proximal neck diameter between 18 and 30 mm, neck angulation between 60 degrees and 90 degrees , and/or severe iliac artery angulation/tortuosity. Between September 2005 and April 2009, 20 men (mean age 72.4+/-7.7 years, range 55-89) were enrolled in the study. The mean AAA diameter was 61.8+/-14.9 mm (range 45.5-102). The mean angulation of the proximal neck was 61.9 degrees +/-16.5 degrees (range 30 degrees -90 degrees ); in the iliac arteries, the angulation was 59.9 degrees +/-16.3 degrees (range 30 degrees -85 degrees ) for the left and 60.9 degrees +/-17.6 degrees (range 28 degrees -90 degrees ) on the right. Fourteen (70%) patients had60 degrees proximal neck angulation. Outcome measures were analyzed using life-table analysis.The graft was successfully implanted in all but 1 patient (technical success 95%); failure to cannulate the contralateral iliac limb resulted in conversion to aortomonoiliac stent-graft placement. In 1 patient, bilateral renal artery stent rescue was performed due to severe procedure-related stenosis. Occlusion of an internal iliac artery was noted in 2 patients. Mean follow-up was 26.9 months (range 4.5-43.5). No aneurysm-related rupture or death occurred. Two endoleaks were observed: 1 type I without migration at 3 years and 1 type II at 13 months. Freedom from any type of endoleak was 91.6% at 1 year and 75.9% at 2 years. Freedom from any early or late intervention was 88.8% at 1 year and 76.0% at 2 years. Aneurysm sac shrinkage (5 mm) was evident in 79% (11/14) of the cases reaching 12-month follow-up.The Aorfix device seems to be safe and reliable in purely complex infrarenal AAA anatomy, demonstrating good short and midterm clinical outcomes. Further larger or multicenter studies are needed to confirm the suitability of the Aorfix stent-graft in hostile infrarenal AAA anatomy.

Patients with rest pain or acute peripheral arterial thrombosis are known to have impaired endogenous fibrinolysis, which is associated with an increased risk of early vascular graft thrombosis. This risk is exacerbated by the fibrinolytic shutdown which is known to occur after major surgery. Stanozolol, which has been demonstrated to enhance endogenous fibrinolysis, was therefore used in an attempt to prevent this perioperative fibrinolytic shutdown and so enhance graft patency. Twenty-seven patients were randomized to receive either 50 mg stanozolol or placebo intramuscularly 24 h before operation, followed by a 6 week course of either 5 mg stanozolol or placebo orally, twice daily. On the second day after operation, 10–11 MBq of autologous 111indium-labelled platelets were injected, with scanning over the graft on the 3 following days. Despite using a large depot of stanozolol, significant effects, such as raised plasminogen (P < 0·001), reduced fibrinogen (P < 0·001) and reduced euglobulin lysis time (P < 0·001), were not seen until the seventh day after operation, with maximum benefit at 6 weeks. This was reflected in the 111indium-labelled platelet deposition studies. The placebo group had a progressive increase in platelet deposition on all 3 days. In contrast, those receiving stanozolol showed a lower, static picture of deposition. However, these changes did not attain statistical significance. Three patients experienced early graft thrombosis, two in the placebo group and one in the stanozolol group. Only an incomplete inhibition of the perioperative fibrinolytic shutdown was achieved. Much longer preoperative courses are thus required to allow the maximum effect to be present at the most crucial time. At present, perioperative fibrinolytic enhancement does not appear to be a practical proposition, and we must await the development of new safer and more potent agents.

Over a 10-year period 23 patients had a clinical diagnosis of axillary/subclavian vein thrombosis; excluded from the study are those thromboses secondary to carcinomatosis, local surgery or radiotherapy. At a median follow-up of 16 months (range 3–120), six patients had died and five patients had moved away. Twelve patients were reviewed (nine male and three female) with a median age of 30 years (range 18–62). All had been managed conservatively with arm elevation, heparinization and warfarin therapy. Five patients (42%) were clinically symptomatic, necessitating a change in employment in three patients (25%). Objective signs of chronic venous insufficiency were demonstrable in the same five patients (42%). Repeat venography was obtained in 11 patients, seven of whom were asymptomatic. Evidence of recanalization was seen in nine patients (82%); however, there was no correlation between clinical symptoms and radiographic findings. This disparity highlights the importance of clinical examination over persistent venographic changes in the evaluation of new treatment methods attempting to reduce the morbidity of this condition.

A total of 119 patients with acute peripheral arterial ischaemia were studied prospectively to validate the definition of acute critical ischaemia suggested by the working party of the International Vascular Symposium. The majority of the patients had primary treatment using thrombolytic therapy. Overall limb salvage after 30 days was achieved in 56% of the patients, 19% required amputations and 25% died. Comparisons of the outcome in patients with or without a distal neurosensory deficit (limb salvage 30% vs. 72%, P = 0.0001) and those with absent or audible Doppler ankle blood flow (limb salvage 37% vs. 78%, P = 0.0001) confirmed that the severity of the initial ischaemia was a significant indicator of prognosis. The definition of acute critical ischaemia as assessed by objective measurement of Doppler pressures has been validated and can be used to divide patients into groups with critical and sub-critical ischaemia with different prognoses.

Background Aortic aneurysm anatomy is crucial when considering patients for endovascular repair. The aim of this study was to determine the proportion of patients with aortic aneurysm suitable for endovascular repair with three different graft-stent systems. Methods Spiral computed tomographic angiography was used to assess the anatomy of 154 abdominal aortic aneurysms. Measurements were made of aneurysm neck length and diameter, renal artery to aortic bifurcation length, common iliac artery diameter and length, and external iliac artery diameter. Aneurysms were assessed for anatomical suitability for currently available aortoaortic, aortobi-iliac and aortouni-iliac devices. Results Six patients (4 per cent) had a distal aortic neck suitable for implantation of a straight aortic graft. Fifteen patients (10 per cent) had arterial anatomy suitable for implantation of a bifurcated graft and 85 (55 per cent) patients were suitable for endovascular repair with an aortouni-iliac graft. The primary reasons for unsuitability were: proximal neck length less than 1.5 cm (44 patients), proximal neck diameter greater than 3.0 cm (12), and angulation of the proximal neck (three). A further ten patients were considered unsuitable for an aortouni-iliac graft because of bilateral common iliac artery aneurysms (four), tortuous iliac arteries (four) and narrow external iliac arteries (two). Conclusion The aortouni-iliac device has the widest applicability of the currently available endovascular systems but open repair remains the only option for a large proportion of patients.

Introduction Endovascular aneurysm repair (EVAR) with aortouniiliac prostheses extends the morphologic range of aneurysms that can be treated and is potentially a more rapid and simple operation than bifurcated endovascular repair. It may, however, be limited by durability of the femorofemoral extra-anatomic bypass graft required to revascularize the contralateral lower limb. Previous studies of femorofemoral bypass grafts were performed almost exclusively in patients with occlusive disease. An 8-year single center experience with use of the femorofemoral bypass graft in aneurysmal disease is reported. Methods All patients undergoing EVAR with an aortouniiliac endovascular stent graft over eight years (1994-2002) at a single institution were included in a retrospective study. Patient data were collected from a prospectively maintained local endovascular database. All patients gave informed consent and were part of an endovascular program approved by the local ethics committee. Results Over the 8 years, 231 patients underwent EVAR with an aortouniiliac endovascular stent-graft. Median follow-up was 22 months. Localized wound complications were observed in 25 patients (11%). Cumulative 3-year patency rate for the femorofemoral bypass graft was 91%. At the end of 5 years 83% of grafts remained patent. Conclusions The femorofemoral bypass graft used during EVAR with aortouniliac stent grafts offers encouraging medium and long-term patency. When graft occlusion occurs, it is usually directly attributable to inadequate inflow from the endovascular stent graft itself or to endoluminal damage of the external iliac artery. Awareness and early detection of stent-graft distortion or complications in the external iliac artery may result in improved patency rates.

Purpose: To assess the anatomical suitability of ruptured abdominal aortic aneurysms (AAA) for emergency endovascular repair. Methods: All cases (46 patients [35 men; mean age 74 years, range 54–85]) in which computed tomographic angiography (CTA) confirmed AAA rupture over a 5-year period at our university hospital were reviewed for anatomical suitability for endovascular repair. Measurements were made by a radiologist experienced in anatomical assessment of CT criteria for elective endovascular aneurysm repair (EVAR). Results: The mean aneurysm neck length was 18 mm (range 0–59); 17 were conical, 13 straight, 4 barrel, and 6 reverse conical. Six cases had no proximal neck. Overall, 37 (80%) patients were unsuitable for EVAR according to our criteria. Nearly half the patients (22, 48%) had ≥2 adverse features. Unsuitable neck morphology (35, 76%) was the primary reason for exclusion, but CIA aneurysm (10, 22%) and EIA tortuosity (7, 15%) were secondary adverse features. Conclusions: With current stent-graft design, the majority of ruptured abdominal aortic aneurysms are anatomically unsuitable for endovascular repair.

After endovascular repair of abdominal aortic aneurysm with endografts with suprarenal stents, the proximal uncovered stent may cross the origin of the superior mesenteric artery. Effects on splanchnic circulation are unknown and may include development of stenosis at the vicinity of the stent. The criteria of high-grade superior mesenteric artery stenosis using color duplex ultrasonography have been previously reported. The purpose of this study is to examine the incidence of high-grade superior mesenteric artery stenosis in patients with endografts with suprarenal stents using color duplex ultrasonography. Candidates for the study were patients who had placement of an aortic endograft with a suprarenal stent and were able to undergo ultrasonography of the superior mesenteric artery. After reviewing computed tomography scans, patients who had the origin of the superior mesenteric artery crossed by the suprarenal stent underwent color duplex ultrasonography of this vessel. Presence of turbulence or narrowing of the superior mesenteric artery, or a peak systolic velocity greater than 2.75 m/sec, or an end-diastolic velocity greater than 0.45 m/sec were considered significant for the presence of high-grade superior mesenteric artery stenosis. There were 24 patients (21 males, three females), median age 71 years (range, 59-83). The suprarenal stent was crossing the superior mesenteric artery in 17 of 24 patients (71%). Color duplex ultrasound was technically successful in 13 of 17 (76%). The test was performed after a median follow-up of 9 months (range, 3 days to 34 months). No patient had evidence of turbulence or narrowing of the superior mesenteric artery during ultrasonography. The median peak systolic velocity was 0.92 m/sec (range, 0.53-1.21 m/sec). No patient had peak systolic velocity greater than 2.75 m/sec. The median end-diastolic velocity was 0.10 m/sec (range, 0.09-0.14 m/sec). No patient had end-diastolic velocity greater than 0.45 m/sec. Color duplex ultrasonography did not demonstrate the presence of high-grade superior mesenteric artery stenosis during early follow-up of patients with endografts with suprarenal stents. Longer follow-up of larger series of patients is needed to determine the long-term effects of suprarenal stents on splanchnic circulation.