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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.)

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.

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.

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.)

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.

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.)

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.

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.

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.

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.

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.

Introduction obtain or maintain a secure seal between the aortic wall and a transluminally implanted intra-aneurysmal Prevention of aneurysm rupture is the primary aim graft”. Type I, or attachment site endoleak, causes continued filling of the AAA leading to increased of treatment of abdominal aortic aneurysm (AAA). Early enthusiasm for endovascular aneurysm repair pressure and eventual rupture. Type II, or retrograde endoleak, was first described (EVAR) has been tempered by sobering reports of aneurysm sac rupture, despite apparently successful in 1998. The significance of type II endoleak is largely unknown and its natural history has generally been initial treatment. These catastrophes have largely been attributed to graft migration and endoleak. thought to be benign. There was no increase in aneurysm diameter during an 18 month follow-up of Endoleak is a term that describes “the inability to type II endoleak in one study. Despite this, there has been one reported case of predicted aneurysm sac rupture due to persistent sac perfusion from an accessory renal artery. We report a case of fatal aneurysm sac rupture secondary to a known type II endoleak (inferior mesenteric artery).

Objectives:to determine (a) changes in aneurysm size following endovascular repair, (b) the significance of collateral lumbar artery blood flow and (c) the relationship between thrombus distribution within the aneurysm sac and the development of a “lumbar endoleak”.Materials and Methods:72 patients treated with endovascular stent-grafts were followed up with spiral computed tomography for a median of 11 (range 3–27) months. The cross-sectional area of the aneurysm was measured at the point of maximum diameter pre- and post-operatively. The distribution and quantity of thrombus was recorded pre-operatively and this was related to changes in aneurysm size and the development of lumbar endoleaks post-operatively.Results:an increase in aneurysm size occurred in 22 patients, of whom 10 had endoleaks. Fifteen aneurysms did not change in size, including four with endoleak, and 35 aneurysms decreased in size with no endoleaks. There was a significant difference between the endoleak and no endoleak groups (Chi-squared test = 17.1 with 2 degrees of freedom (d.f.), p

Objective: The following procedures are the 3 main methods of endovascular repair (EVR) of abdominal aortic aneurysms (AAA): aorto-aortic bypass grafting, bifurcated bypass grafting, and aorta uni-iliac grafts. The latter method has the potential disadvantage of requiring an extra anatomic graft (ie, a femorofemoral crossover bypass graft) to maintain contralateral pelvic and limb perfusion. The aim of this study was to assess the complications associated with the femorofemoral crossover bypass graft after aorta uni-iliac EVR of AAA. Method: A prospective review was conducted of the complications attributable to the femorofemoral crossover bypass graft in 136 patients who underwent EVR of AAA with an aorta uni-iliac device. Results: During a median follow-up of 7 months (range, 0 to 36 months), 4 patients had superficial wound infections that required antibiotic treatment and 2 patients had bypass graft infections. Nine hematomas developed: 7 (5%) groin hematomas (6 in patients with Dacron bypass grafts), 1 scrotal hematoma, and 1 perigraft hematoma. One bypass graft thrombus developed. Conclusion: The femorofemoral crossover bypass graft is a safe and a durable component of EVR of AAA with an aorta uni-iliac device. The results are similar to those with bifurcated devices. (J Vasc Surg 1998;28:647-50.)

OBJECTIVES To determine the incidence of common iliac artery (CIA) aneurysms in patients with abdominal aortic aneurysms (AAA) and to evaluate the relationship between AAA and CIA diameter. METHODS Spiral CT angiography was used to measure the maximum diameters of the abdominal aorta and the common iliac arteries of 215 patients with AAA. RESULTS The median CIA diameter was 1.7 cm--significantly greater than the published mean of 1.25 (2 S.D. = 0.85-1.65) cm of an age-matched, non-vascular population. Thirty-four patients (16%) had unilateral and 26 patients (12%) bilateral CIA aneurysms > or = 2.4 cm diameter. Eight-six vessels (20%) were affected. Right CIA diameters were wider than left CIA diameters (p < 0.0001, Wilcoxon matched-pairs signed rank test). The correlation between AAA size and CIA diameter was weak. CONCLUSIONS The AAA population has abnormally dilated common iliac arteries. In this population, common iliac artery aneurysms should be defined as those greater than 2.4 cm diameter. 20% of CIAs in patients with AAA are aneurysmal according to this definition.

Purpose: The purpose of this study was to test a transfemoral system of bifurcated endovascular graft insertion for aortic aneurysm repair.Methods: Bifurcated endovascular grafts were inserted through bilateral femoral artery cutdowns in 41 patients. The results were assessed by completion angiography and follow-up computed tomography.Results: The second half of the study included more aneurysms 6 cm or larger (p < 0.05) and more instances of short proximal neck (p < 0.05), proximal neck angulation (p < 0.05), and iliac angulation (p < 0.05). Despite the increasingly challenging anatomy, the results were better in the second half of the study as illustrated by the lower overall combined morbidity/mortality rate (15% vs 50%) and higher overall success rate (85% versus 65%). The mortality rate for the series as a whole was 7.5%. Mean follow-up was 18.8 months for the first 20 patients and 10.9 months for the second 20. The commonest complication in the first half of the study was graft thrombosis (n = 5). This complication was absent from the second half of the study because of routine adjunctive stenting. Two patients died of complications of endovascular repair. In both cases aneurysm rupture on the third postoperative day was associated with coagulopathy and angiographic signs of perigraft leak.Conclusion: Aneurysm exclusion with a bifurcated endovascular graft was feasible in a wide range of patients, but when the aneurysm was not entirely excluded from the circulation, the risk of rupture persisted. (J Vasc Surg 1996;24:655-66.)

Endoluminal transfemoral repair of abdominal aortic aneurysm (AAA) is an important development but large aneurysms seldom have a distal neck suitable for the currently available devices for a straight aortoaortic graft1–3. A bifurcated graft system overcomes the limitation of lack of distal neck but it is unsuitable for a significant proportion of aneurysms because of a wide or aneurysmal iliac vessel1. An alternative technique of aorto-uni-iliac graft with occlusion of the contralateral common iliac with embolization and a femorofemoral crossover graft is described.

Pulse spray thrombolysis is a technique of accelerated peripheral thrombolysis which has been evaluated in 38 patients, 29 with threatened limb viability and nine with a viable but critically ischaemic limb. The median length of occlusion was 26·5 (range 3–65) cm. The lytic agent used was recombinant tissue plasminogen activator (rtPA), injected manually via a pulse spray catheter at a concentration of 0·33 mg/ml and a bolus size of 0·2ml. The median total dose of rtPA was 18 (range 5–35) mg. Patency and flow were completely restored in 34 of 38 patients and clinical success at 30 days was maintained in 27 of 38. The median lysis time was 120 (range 35–1125) min, compared with a median duration of 1545 (range 42–5760) min in 120 consecutive patients previously treated with conventional low-dose infusion thrombolysis using rtPA. This represents a 12-fold reduction in lysis time (P < 0·001). The overall estimated cumulative limb salvage rate for the 38 patients who entered the study was 84 per cent and the cumulative patency rate for the 34 patients in whom patency was restored was 74 per cent at 18 months follow-up. Pulse spray thrombolysis rapidly restores patency with good limb salvage at 30 days; the benefit is sustained even in patients with limbs at immediate risk of irreversible ischaemic injury who are not considered suitable for conventional thrombolysis.

The results of local intra-arterial thrombolysis in 98 patients treated with streptokinase and 69 patients treated with recombinant tissue plasminogen activator (rtPA) have been compared. The two groups of patients were well matched and their treatment protocols were identical except with regard to the thrombolytic agent used. Strict criteria for defining successful thrombolysis were used. Successful lysis was achieved in 40 of 98 patients (41 per cent) receiving streptokinase and 40 of 69 patients (58 per cent) receiving rtPA (P < 0·05). The time to lysis was significantly shorter with rtPA, median time 22h, than with streptokinase, median time 40 h (P < 0·002). There was no diference in the incidence of haemorrhagic complications. These results suggest that rtPA is superior to streptokinase for local intra-arterial thrombolysis.

Arteriography does not reliably distinguish between acute and chronic arterial occlusions. Seventeen patients with acute lower limb ischaemia were investigated by arteriography and by imaging with a platelet-specific monoclonal antibody (P256 Fab'); 20 MBq 111In-labelled P256 Fab' was administered intravenously and patients were imaged at intervals of between 20 min and 24 h. Thirteen patients were subsequently treated with intra-arterial thrombolysis. In six the images showed foci of increased uptake of 111In-labelled P256 Fab' and the corresponding arterial segment was recanalized. Patency to 30 days was maintained in four cases. Seven patients had negative scans, only four of whom achieved lysis, and two of these suffered early rethrombosis. The remaining four patients were excluded from thrombolysis by the arteriographic appearances. 111In-labelled P256 Fab' imaging can identify sites of acute arterial thrombosis and may have clinical applications in the management of peripheral vascular disease. Further studies are required to test whether the technique has a role to play in patient selection for thrombolysis.

Sixty patients were recruited into a randomized parallel group comparison of three thrombolytic regimens for acute or subacute peripheral arterial thrombosis. There were no significant differences in age, duration of history, length of occlusion or presence of neurosensory deficit between the groups. Initially successful lysis was significantly greater with intra-arterial (IA) recombinant tissue plasminogen activator (rt-PA) than with either streptokinase (Sk) (P < 0·04) or intravenous (IV) rt-PA (P < 0·01). The duration of therapy varied from a median of 35 h with IA rt-PA to 40 h with Sk (P > 0·5). The median (confidence interval) increase in ankle:brachial pressure index following IA rt-PA of 0·57 (0·33–0·82) was significantly higher than for either Sk of 0·24 (0–0·57) or for IV rt-PA of 0·18 (0–0·41). Limb salvage at 30 days was achieved in 80, 60 and 45 per cent respectively for IA rt-PA, Sk and IV rt-PA. Haemorrhagic complications occurred in six patients following Sk and in 13 following IV rt-PA; only one minor haemorrhage occurred following a catheter perforation in a patient who received IA rt-PA (P < 0·05). IA rt-PA provides a more effective, safer fibrinolytic regimen than conventional therapy with Sk. IV rt-PA has not been as successful and carries a significantly higher risk of haemorrhagic complications.

Thirty acute peripheral arterial thromboses in 28 patients were treated with local low-dose intra-arterial recombinant tissue plasminogen activator (t-PA). All patients received 0·5 mg h−1 t-PAand 15 also received 250 units h−1 of intra-arterial heparin. Overall limb salvage at 30 days was 83 per cent (25 out of 30 limbs). Mean(s.d.) ankle/brachial index was increased by 0·53(0·26) and there was no significant difference between the group receiving t-PA alone and that receiving t-PA and heparin. No strokes or major haemorrhages occurred but there were four (13 per cent) minor haematomas associated with the catheter entry site. There were four (13 per cent) deaths from myocardial infarction occurring between 5 and 21 days after treatment. Rethrombosis occurred in four cases (13 per cent). In two patients following t-PA alone, rethrombosis occurred after 2 and 11 days. Limb salvage was achieved with a successful repeat thrombolysis and a femoropopliteal graft respectively. Rethrombosis after t-PA and heparin occurred after 30 days in two patients due to poor run-off and extensive proximal atheromatous disease respectively. t-FA is a safe, effective thrombolytic agent when given as a low-dose intra-arterial infusion. The addition of low-dose heparin does not produce any significant benefit.

Traditional open repair of abdominal aortic aneurysm has disadvantages. We present our experience of transfemoral endoluminal repair with a bifurcated graft system. 29 patients with aortic aneurysm over 5·5 cm in diameter and 1 with a 3·2 cm aneurysm and bilateral iliac stenosis were assessed; 5 were suitable for the procedure. The operation was successful in all the patients, without haemodynamic compromise or major complications. This technique has the potential to reduce morbidity and mortality from abdominal aortic aneurysm. Further modifications are required to make it applicable to most aneurysms.

Background Endovascular repair (EVR) of abdominal aortic aneurysm (AAA) is feasible for selected patients. Placing an uncovered stent across the origins of the renal arteries may improve fixation and seal of the proximal end of the stent-graft. However, this has potential for problems (e.g. renal artery stenosis or microembolization). This study aimed to evaluate the short-term effect of a suprarenal stent on the function of the individual kidney. Methods In 30 patients undergoing EVR for AAA, renal function was assessed before and after operation by 99mTc-radiolabelled diethylenetriamine penta-acetate radionuclide renography and daily measurement of serum creatinine levels. Eleven patients had infrarenal stent-grafts using an aorta uni-iliac system (group 1); 19 patients had the device with an uncovered suprarenal stent (modified Gianturco Z stent), ten of which were aorta uni-iliac and nine bifurcated systems (group 2). Individual kidney function was expressed as the whole kidney transit time (WKTT). In addition, glomerular filtration rate (GFR) was measured from serial blood samples following renography. Conclusion No result reached statistical significance. Placing an uncovered stent over the origins of the renal arteries does not appear to impair kidney function in the short term.

Background The aim of endovascular repair of an abdominal aortic aneurysm is to exclude the aneurysm from the systemic circulation in order to prevent aneurysm expansion and rupture. Lumbar artery (LA) endoleaks have been associated with continued expansion of the aneurysm sac and occur with a reported incidence of approximately 10 per cent. The aim of this study was to reduce the incidence of LA or inferior mesenteric artery (IMA) endoleaks. Methods Following deployment of an aortic uni-iliac graft an aneurysmograph was performed by injecting contrast into the aneurysm sac to look for patent aortic side branches. Patients with no visible side branches had an occluder deployed in the contralateral iliac artery. Patients with patent side branches had an absorbable gelatin sponge inserted into the aneurysm sac before occluder deployment. Patients had contrast-enhanced spiral computed tomography (CT) during follow-up at 1 week, and 3, 6 and 12 months. Results Fifty-four patients were studied. Eleven were excluded (two perioperative deaths, seven top endoleaks and two occluder endoleaks). Median follow-up was 2 (range 11–7) months. Of the 17 patients in whom patent vessels were demonstrated on an aneurysmograph, one had a patent IMA only, three had a patent LA and IMA, and the remainder had a patent LA. No patient within the study has had a LA or IMA endoleak identified at follow-up CT. Conclusion An intraoperative aneurysmograph can help select patients for aneurysm sac packing with gelatin sponge and has been successful in the short term in preventing LA and IMA endoleaks.

Background Dilatation of the proximal neck following conventional open repair of abdominal aortic aneurysm (AAA) has been reported. Such continued dilatation following endovascular repair (EVR) could potentially be a disaster resulting in graft slippage, endoleak and aneurysm rupture. The aim of this study was to detect any change in proximal neck diameter following EVR of AAAs. Methods One hundred patients had undergone EVR of an AAA over a 4-year period in whom contrast-enhanced spiral computed tomography was performed both before and after EVR (1 week, 3, 6 and 12 months and annually thereafter). Change in aortic proximal neck diameter, change in maximum aortic diameter, presence of endoleaks, and change in length from the lowest renal artery to the aortic bifurcation was sought. Results The median anteroposterior and transverse diameter decreased from 64 mm before operation to 56 and 54 mm respectively after operation. This trend in reduction in maximum diameter was not seen in patients with endoleaks. There was no significant change in proximal neck diameter when measured at 5-mm intervals following EVR. There was also no significant change in the aortic length following EVR. Conclusion There was no evidence of proximal neck dilatation or aneurysm length reduction following EVR of AAAs.

The effects of mannitol on renal impairment following infrarenal aortic aneurysm repair were studied. Patients received either mannitol 0.3 g/kg (n = 15) or saline (n = 13) as a rapid intravenous infusion before aortic cross-clamping. One patient in the control group developed fatal postoperative renal failure but there was no renal failure in the mannitol group. Two patients treated with mannitol died from perioperative myocardial infarction. There were no significant differences in postoperative blood urea level, serum creatinine concentration or creatinine clearance between mannitol and control groups. In patients who had mannitol there was a significant diuresis on the first day after operation (mean urine output 2250 ml) compared with before operation (1557 ml) (P = 0.007). Compared with controls, patients treated with mannitol had lower mean (s.e.m.) postoperative levels of urinary albumin (160(32) versus 500(140) mg per mmol creatinine; P = 0.036) and N-acetyl glucosaminidase (143(34) versus 271(70) mumol per mmol creatinine; P = 0.04) indicating a reduced level of subclinical glomerular and renal tubular damage. These data demonstrate that mannitol reduces subclinical renal injury following infrarenal aortic aneurysm repair.

Thirty-two patients with acute and subacute limb-threatening peripheral arterial ischaemia were treated with low dose intra-arterial streptol ase infusions. The mean duration of infusion was 38 h. Six patients developed pericatheter thrombosis and two had distal embolization of fragments of thrombus but in all cases these responded to repositioning the catheter and continuing the infusion. Five patients developed groin haematomata and in three of these there was evidence of a systemic fibrinolytic effect from the streptokinase with plasma fibrinogen reduced below 1 g/l. The most serious complication was perforation of the popliteal and tibial arteries which occurred on two occasions and required cessation of the infusion. Twenty-two patients (69 per cent) achieved limb salvage, eight (25 per cent) suffered a major amputation and two (6 per cent) died. The outcome was not related to the site, nature or duration of the arterial occlusion but patients with loss of sensation or paralysis of the affected limb were significantly less likely to obtain limb salvage (P = 0.001). For occlusions greater than 30 cm in length a new technique was used where the thrombus was lysed from distal to proximal in short lengths by gradual catheter withdrawal. This was successful in five out of six cases. Low dose intra-arterial streptokinase has been confirmed as an effective, relatively safe method of treatment in recent arterial ischaemia and can be recommended in situations where the results of surgery may not be favourable. In particular, patients with arterial thromboses and no distal run-off, distal and late arterial emboli, thrombosed popliteal aneurysms and patients after a failed embolectomy, have all been shown to respond to thrombolytic therapy with intra-arterial streptokinase.

Resting plasma fibrinolytic activity and fibrinolytic activity after stimulation by 10 min of venous occlusion (fibrinolytic potential) were estimated in 51 patients before femoropopliteal reconstructive surgery. Twelve patients suffered a graft thrombosis in the first month. Resting plasma fibrinolytic activity was similar in patients with thrombosed grafts and those with functioning grafts. However reduced fibrinolytic potential was found to be a risk factor for graft thrombosis in the month after surgery (P = 0·01). Other risk factors were increasing age (P = 0·007) and the indication for surgery (P = 0·03). Thirty-four patients whose grafts were functioning after 1 month were followed up for a mean of 9 months. A further eight grafts thrombosed. Neither fibrinolytic activity nor fibrinolytic potential were found to be risk factors for late graft thrombosis. Fibrinolytic potential has been shown to be an independent risk factor for early graft thrombosis. Peri-operative fibrinolytic stimulation might be a method of improving femoropopliteal graft patency.

Twelve patients with a clinical diagnosis of possible vascular graft infection have been studied over the last 3 years. All patients had their leucocytes labelled with indium-111 and γ-camera imaging after 24 and 48h. Subsequent management was according to established surgical techniques. Eight patients proved to have vascular graft infection and indium uptake was seen along the length of the graft in six. Two patients with open wound infections and synthetic grafts had localized uptake only on leucocyte scanning. Four patients, all of whom had negative scans were not thought to have infected grafts after further investigation using digital subtraction angiography and computed tomography scanning. These patients have been followed up for a median period of 19 months (range 5–25 months) and have remained symptom free. Initial experience with 111In-labelled leucocyte scanning has been encouraging, both in diagnosis and in planning the management of patients with graft infections.

The use of local low dose thrombolysis is gradually increasing. Most experience is with streptokinase, although newer agents such as recombinant tissue plasminogen activator (rTPA) may offer more effective lysis with reduced complications. We have reviewed the experience documented in 19 prospective series published between 1974 and 1988 in an attempt to define the incidence of stroke, major haemorrhage and minor haemorrhage. The overall risk of stroke was 1·0 per cent. of patients (14 cases). Major haemorrhage occurred in 5·1 per cent of patients (71 cases) and minor haemorrhage occurred in 14·8 per cent (92 out of 620 cases). There was little difference between the two thrombolytic agents, although the experience with lower doses of rTPA suggests it may offer a reduced risk of haemorrhagic complications. It is essential that all studies concerning thrombolysis should give their exclusion and inclusion criteria in full to allow an accurate appraisal of haemorrhagic complications, with the hope of improved patient selection and reduced morbidity in the future.

Purpose: The purpose of this study was to assess the incidence and management of intraoperative technical problems during endovascular repair (EVR) of complex abdominal aortic aneurysms (AAA). Methods: From February 1995 to March 1999, 204 EVRs of nonruptured AAA were performed at our institution. One hundred seventy-six patients had an in-house custom-made graft; 172 were aorto–uni-iliac grafts, and four were aortoaortic grafts. Twenty- eight patients had a bifurcated graft. One hundred fourteen patients (56%) were high risk for conventional open repair. One hundred nine patients (53%) were not suitable for most commercially available devices. Results: Intraoperative technical problems occurred in 81 patients (40%). There were 37 endoleaks (27 proximal, 10 distal), 15 graft stenoses, one failure of graft deployment, two graft thromboses, three aortoiliac ruptures, five renal artery occlusions (one bilateral, four unilateral), and 18 internal iliac occlusions (five bilateral, 13 unilateral). Endovascular management of these problems was successful in 37 of the 81 patients (46%) and included 15 balloon dilatations, 21 additional stent placements, and one graft thrombectomy. Fifteen of the 81 patients (19%) had open procedures (four periaortic ligature placements, six open aneurysm repairs, three common iliac ligations, and two extra-anatomic bypass grafts). In the remaining 29 patients, the on-table problem was managed expectantly. During follow-up, two of 37 patients (5%) who were treated successfully with endovascular procedures experienced recurrence. There were five deaths (33%) among the 15 patients who underwent open procedures. Conclusion: Intraoperative problems occur frequently during the endovascular management of complex aneurysms. Many of these problems can be managed with additional endovascular techniques without an increased risk of recurrence or procedure-related complications. Open procedures in high-risk patients carry a high mortality rate. The team performing EVR of AAA should be skillful in advanced endovascular and open surgical procedures. (J Vasc Surg 2000;31:1185-92.)

Objective to show how differences in anatomical and physiological risk factors can affect the outcome of endovascular repair of AAA by describing the experience of two centres with different selection policies. Methods one hundred and thirty-five patients (group I) were treated at Queen's Medical Centre (Nottingham, U.K.) using 101 in-house made and 34 manufactured stent-grafts. Median diameter, length and angulation of the proximal aneurysm neck were 26 mm, 27 mm, 40°, respectively. Seventy-six patients had ischaemic heart disease, 47 had left ventricular failure, median forced expiratory volume in one second (FEV1) was 83%, median creatinine was 100 μmol/l and median age was 72 years. Fifty patients (group II) were treated at Timone Hospital (Marseilles, France) using seven in-house made and 43 manufactured stent-grafts. Median diameter, length and angulation of the proximal aneurysm neck were 25 mm, 34 mm, 33°, respectively. Thirteen patients had ischaemic heart disease, two had left ventricular failure, median forced expiratory volume in one second was 101%, median creatinine was 108 μmol/l and mean age was 72 years. Results anatomical characteristics of the proximal neck were significantly worse in group I (p=0.02 for the three variables). Cardiac comorbidities were more frequent and mean FEV1 was lower in group I (p

Objective: Endoleaks and endotension are critically important complications of some endovascular aortic aneurysm repairs (EVARs). For the resolution of controversial issues and the determination of areas of uncertainty relating to these complications, a conference of 27 interested leaders was held on November 20, 2000. Methods: These 27 participants (21 vascular surgeons, five interventional radiologists, one cardiologist) had previously answered 40 key questions on endoleaks and endotension. At the conference, these 40 questions and participant answers were discussed and in some cases modified to determine points of agreement (consensus), near consensus (prevailing opinion), or disagreement. Results: Conference discussion added two modified questions for a total of 42 key questions for the participants. Interestingly, consensus was reached on the answers to 24 of 42 or 57% of the questions, and near consensus was reached on 14 of 42 or 33% of the questions. Only with the answers to four of 42 or 10% of the questions was there persistent controversy or disagreement. Conclusion: The current endoleak classification system with some important modifications is adequate. Types I and II endoleak occur after 0 to 10% and 10% to 25% of EVARs, respectively. Many (30% to 100%) type II endoleaks will seal and have no detrimental effect, which never or rarely occurs with type I endoleaks. Not all endoleaks can be visualized with any technique, and increased pressure (endotension) can be transmitted through clot. Aneurysm pulsatility after EVAR correlates poorly with endoleaks and endotension. An enlarging aneurysm after EVAR mandates surgical or interventional treatment. These and other conclusions will help to resolve controversy and aid in the management of these vexing complications and should also point the way to future research in this field. (J Vasc Surg 2002;35:1029-35.)

Objectives: To study the use of carbon dioxide as a contrast medium for arteriography. Methods: Carbon dioxide was used as a contrast medium for intra-arterial digital subtraction lower limb angiography in 12 examinations on 11 patients. Results: No complication was encountered and no significant changes occurred in the arterial pH,PaCO 2 and PaO 2 . The quality of images as assessed by an independent observer was adequate for the majority of the vessels (77%). Conclusions: Carbon dioxide is a safe alternative in patients at an increased risk of adverse reaction to iodinated ionic or non-ionic contrast medium and is very cheap.