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Endovascular aneurysm repair (EVAR) offers a minimally invasive alternative to open repair and has the benefits of reduced perioperative morbidity and mortality. There are potential complications specific to EVAR, including device failure, graft migration, and endoleak, which necessitate long-term follow-up. This remains a relatively novel technique, and therefore, little long-term data exist. This study reports 5-year EVAR outcome data from a single center. Five-year follow-up data for 58 patients at a single center who underwent EVAR using a variety of different commercial devices was reviewed. All patients were followed up with 6-monthly duplex ultrasound scanning and clinical assessment in a nurse-led clinic, in addition to yearly computed tomographic (CT) scans for those participating in the EVAR trial. All patients in this series were male, with a median age of 72 years (range 58-81). Mean preoperative aortic diameter was 5.95 cm, and this reduced following EVAR to 5.2 cm (mean diameter) at 5 years. Mean hospital stay was 7 days, and there were no perioperative deaths. There were 20 (34%) early and 15 (26%) late complications. There were 13 endoleaks confirmed on CT; four (31%) were type I and nine (69%) were type II. All-cause mortality was 26%. There were no late aneurysm-related deaths. EVAR has the advantages of shorter hospital stay and reduced perioperative morbidity and mortality. Long-term follow-up remains a priority following aortic stenting in order to detect late complications such as endoleak.

Emergency EVR for ruptured AAA is now technically feasible, and several reports with small numbers have appeared in the literature from major centers suggesting that the results may be the same as or better than seen with open repair. The immediate priority is avoidance of over-resuscitation together with the rapid transfer of the patient to CT and then to the operating theater. Because of the learning curve involved, these cases should be attempted only by major centers that have extensive elective endovascular experience. The requirement for 24-hour availability of surgeons and radiologists trained in endovascular techniques places an enormous strain on vascular and radiologic staff and is achievable only in major centers with large teams of doctors. These issues raise important questions about the delivery of vascular services and whether all cases of ruptured aortic aneurysm should be transferred to major vascular centers. The operating theater staff and other support persons need training in endovascular techniques and in rapid deployment of an aortic occlusion balloon. A wide selection of devices, guidewires, and catheters must be immediately available in the operating theater. The ideal way to establish the role of EVR for ruptured AAA would be a randomized trial, but there might be logistic difficulties in recruiting sufficient numbers in major vascular centers, particularly as screening for AAA becomes more common and reduces the number of cases. There also are ethical issues as to whether these patients can give informed consent for involvement in such a trial. The alternative is for major centers to continue to develop their endovascular programs, to do more cases, and to compare the results with historical controls undergoing open repair.

Background: Because subintimal angioplasty (SA) is a technique that can achieve recanalization of long arterial occlusions, it is considered an alternative to lower limb bypass operations. The aim of this prospective study was to identify the risk factors that affect patency of SA in patients suffering from critical limb ischemia (CLI)., Methods and Results: 51 consecutive infrainguinal SA were done in 46 patients suffered from CLI. The patients were followed-up with regular duplex scans up to 12 months post-intervention. Sex, atherosclerosis risk factors, and some technical details of the procedure (number of patent run-off vessels after the procedure, length and re-entry point of angioplasty) were examined as potential risk factors of patency, using survival analysis statistical techniques. The overall patency rate at 12 months post-intervention was 50%. According to Cox-regression analysis, the factors that affect patency were the number of run-off vessels and the length of occlusion. Patients with two or three run-off vessels had a hazard of occlusion of 0.30 (P = .027) compared to those who had one run-off vessel. The 12-months patency in patients with more than one run-off vessels was 81% vs. 25% in patients with one run-off vessel. Regarding the length of angioplasty, the hazard of reocclusion was 1.02 for every centimeter of occlusion (P = .049)., Conclusions: The number of patent run-off crural vessels after the angioplasty and the length of occlusion are significant risk factors for reocclusion of infrainguinal SA in patients with CLI. Trying to recanalize more than one run-off vessels could raise the SA patency.

Objectives: To describe our experience with iatrogenic arterio-venous fistula (AVF) occurring during lower limb subintimal angioplasty, their management and the final clinical, radiological outcome., Design: Retrospective review of case series from two centres, from a computerised database over a period of five years., Material: Twelve patients whose lower limb subintimal angioplasty was complicated by Iatrogenic AVF., Results: The Majority of AVF occurred at the popliteal trifurcation vessels. And the incidence of this complication in our case series was 0.8%. This was managed with a variety of techniques-Coil embolisation, balloon tamponade, alternative dissection and stent placement. In one patient, the fistula was left open intentionally. All twelve patients had a successful angioplasty. The overall technical success rate for AVF ablation was eighty percent., Conclusions: AVF is a potential complication of angioplasty. The majority can be managed by endovascular means during the angioplasty procedure with good technical success.

Objective: To investigate the value of duplex ultrasound scanning (DUSS) in the routine follow up of patients following EVAR., Methods: Imaging was reviewed for 310 consecutive patients undergoing EVAR at a single centre. Concurrent ultrasound and CT scans were defined as having occurred within 6 months of each other. There were 244 paired concurrent DUSS and CT scans which were used for further analysis. These modalities were compared with respect to sensitivity, specificity, positive and negative predictive values and level of agreement (by Kappa statistics) using CT as the 'gold standard'., Results: DUSS failed to detect a number of endoleaks which were seen on CT and the sensitivity of this test was therefore poor (67%). However, the specificity of DUSS compared more favourably with a value of 91%. Positive predictive values ranged from 33-100% but negative predictive values were more reliable with values of 91-100% at all time points post operatively. There were no type I leaks, or endoleaks requiring intervention which were missed on DUSS. Overall, there was a 'fair' level of agreement between the two imaging modalities using Kappa statistics., Conclusion: Although DUSS is not as sensitive as CT scanning in the detection of endoleak, no leaks requiring intervention were missed on DUSS in this study. DUSS is much cheaper than CT and avoids high doses of radiation. DUSS therefore remains a valuable method of follow up after EVAR and can reduce the need for repeated CT scans.

Objective: To report the experience of endovascular repair (ER) in patients with ruptured and symptomatic abdominal aortic aneurysms (rAAA and sAAA), comparing results with a cohort of controls who underwent open repair (OR) of sAAA or rAAA., Design: A historically controlled cohort study., Materials: Retrospective data from 21 patients who underwent ER and prospective data from 23 patients who underwent OR., Methods: Results were compared using the Mann-Whitney U-test., Results: Eleven ER patients had sAAAs and 10 had rAAAs. Nine OR patients had rAAAs and 13 had sAAAs. Thirty-day mortality was 11% in patients with rAAA in the ER group, and 54% in the OR group (p=0.03). There were no post-operative deaths in the patients who had an sAAA in the ER group, and one death in the patients who had sAAA in the OR group. Results as expressed as mean ER value versus mean OR value and p-value. ER was associated with significant reductions in the length of operation (2.6 versus 3.1h, p=0.03), blood transfusion requirements (0.86 versus 10.7 units p<0.01), time in critical care (1.5 versus 6.1 days, p=0.02), and total hospital stay (8.5 versus 17.5 days, p=0.01) compared with OR. There was no difference in time from admission to arrival in theatre between the two groups (3.4 versus 5.0h, p=0.35)., Conclusions: In patients with rAAA and sAAA that are suitable for stenting, ER has reduced mortality compared with open repair. Assessment for ER does not cause a pre-operative delay, operating time is reduced, blood transfusion requirements are reduced and there is a faster recovery.

Introduction: Despite advances in surgery, anaesthesia, and critical care, mortality from ruptured abdominal aortic aneurysms (AAAs) has not decreased over the last 20 years. Endovascular aneurysm repair (EVAR) of ruptured AAAs is an alternative to open repair, which may improve outcome. However, a computed tomography (CT) scan is usually required to assess the anatomic suitability of the aneurysm for EVAR. This may result in delay in transferring patients to the operating room. We evaluated all patients admitted to hospital with a ruptured AAA who died without undergoing surgery, to determine time to death after AAA rupture and thus the potential time available for obtaining a CT scan., Methods: A retrospective case note review was conducted of 56 patients admitted to a single center with ruptured AAAs who did not undergo surgery because of advanced age or associated comorbidity over 8 years from 1995 to 2003. Statistical analysis was performed with the Fisher exact test., Results: The 56 patients (33 men, 59%; 23 women, 41%) had a median age of 85 years (range, 71-98 years). Reasons for no operation being performed were shock (9%), cardiac arrest (11%), quality of life (29%), malignancy (7%), cardiac disease (15%), respiratory disease (16%) and age (14%). Median systolic blood pressure at admission was 110 mm Hg, heart rate was 88 beats per minute, and hemoglobin concentration was 10.5 g/dL. Patients were not aggressively resuscitated once a decision was made to not perform surgery. Death within 2 hours of hospital admission occurred in 7 (12.5%) patients, and 49 (87.5%) patients died more than 2 hours after admission. Median interval between onset of symptoms and admission to hospital was 2 hours 30 minutes (range, 44 minutes-36 hours), and the median interval between admission and death was 10 hours 45 minutes (range, 1 hour 1 minute-143 hours 55 minutes). The median total time to death from onset of symptoms was 16 hours 38 minutes (range, 2 hours 6 minutes-146 hours 50 minutes)., Conclusion: Most (87.5%) patients admitted to hospital with a ruptured AAA died after more than 2 hours. These data show that most patients with a ruptured AAA who reach the hospital alive are sufficiently stable to undergo CT and consideration of EVAR.

Objectives: to determine the incidence of early complications following percutaneous transluminal angioplasty and to describe their management and outcome., Materials: five hundred and fifty consecutive patients undergoing angioplasty of 648 limbs, containing 1053 anatomical segments during a two year period were reviewed retrospectively., Results: early complications affected 109 segments (10%) in 92 limbs (14%) of 84 patients (15%). Of the 109 segments affected by early complications, 106 (97%) were managed by endovascular techniques with surgery being required on only three (3%) occasions. There were no deaths attributable to angioplasty., Conclusions: although early complications occur in 14% of limbs undergoing percutaneous transfemoral angioplasty, the majority (97%) can be managed by endovascular techniques.

Aim: To assess the feasibility of endovascular repair (EVR) of wide neck abdominal aortic aneurysms (AAA)., Study Design: Retrospective., Method: A cohort of patient was identified who had an AAA neck diameter of 28 mm or more and underwent EVR. These patients undergo regular follow-up by 6 monthly CT scan of abdominal aorta. Two independent observers quantified the diameter of the suprarenal aorta, the top of the neck, the bottom of the neck, the length of the neck and the transverse diameter of the AAA., Results: The study cohort comprised 16 patients. Bland Altman Analysis determined that the 95% interobserver limits of agreement were -4.7 to 3.3 mm. The mean preoperative diameter of the suprarenal aorta, the top of the neck and bottom of the neck all were 31 mm. On the follow-up CT scan on average after 12 months the suprarenal aorta measured 29 mm, the top of the neck 28 mm and the bottom of the neck 30 mm. There was a statistically significant decrease in the size of the top of the neck (p = 0.03)., Conclusion: This preliminary report suggests that the endovascular repair of AAA with a wide neck is feasible with available commercial devices. The necks do not appear to increase in size and there is no increased incidence of proximal endoleak.

The consequences for lambs of infection over the winter with Teladorsagia circumcincta were quantified by deliberate, trickle infection of selected animals at 7 months of age. Infected and control uninfected animals were each allocated into four groups, relatively resistant animals on a normal diet, relatively resistant animals on an isocaloric diet supplemented with urea, and relatively susceptible animals on the same two diets. Resistance and susceptibility was assessed by faecal egg counts following natural infection during the summer preceding the deliberate infection. During the deliberate infection egg counts remained low and most parasites recovered at necropsy were inhibited larvae. Nonetheless, infection reduced weight gain, decreased albumin and fructosamine concentrations and provoked a noticeable pepsinogen and eosinophil response. As most larvae were inhibited these responses may have been largely a consequence of immuno-inflammatory responses in the host rather than the direct action of parasites themselves. Relatively resistant animals on the supplemented diet allowed fewer larvae to establish and had higher fructosamine concentrations, higher albumin concentrations and decreased pepsinogen responses. Therefore, a combination of relatively resistant sheep and nutritional supplementation appears most efficient at controlling infection.

Endoluminal repair of abdominal aortic aneurysm (AAA) is being adopted as a less invasive alternative to conventional open repair in many centers worldwide. Although the initial results are encouraging, the long-term durability of this procedure remains unknown. Endoluminal AAA repair in 29 patients using three different devices (EVT tube Endograft(R), aortouniiliac device, and Stentortrade mark bifurcated system) is described. Overall, 24 procedures (83%) were completed successfully. Complications included two deaths due to microembolization, five early conversions, two chest infections, three patients with buttock claudication, and three patients with trashed foot. Perigraft leaks were detected in four patients (three proximal, one distal) treated with the EVT tube Endograft. Continued aneurysm expansion was observed in three of the patients. One of the leaks was discovered at the 1-year follow-up. In this patient the aneurysmal process was not retarded by endoluminal repair. The findings in this patient may have implications for the durability of this technique. Therefore, careful long-term evaluation of this procedure is recommended prior to its widespread use.

Objective: To investigate the agreement between colour duplex ultrasonography and digital subtraction arteriography of the infrapopliteal arteries., Design: Retrospective, blinded study., Setting: Vascular laboratory and Radiology Department, University Hospital., Methods: The infrapopliteal vasculature was examined in a total of 51 limbs by both colour duplex ultrasound and digital subtraction angiography. By examining all arteries from the distal popliteal to the pedal arteries, a total of 204 individual arterial segments were available for analysis. Each segment was graded as 0-49%, 50-99% diameter reduced or occluded by both modalities. Using ultrasound, classification of stenoses was achieved by observing peak systolic velocity ratios; a doubling of peak systolic velocity indicating a > or = 50% diameter reducing stenosis. Where no Doppler signal could be obtained, the vessel was assumed to be occluded. From angiographic studies, two radiologists separately and blindly assessed the extent of disease for each infrapopliteal artery noting areas of > or = 50% diameter reduction and occlusion. The Kappa statistic was used to examine the level of agreement between angiography and ultrasound as well as between both radiologists., Results: The Kappa level (95% confidence interval) of agreement between ultrasound and angiographic assessments for distinguishing patent from occluded segments was 0.61 (0.49-0.74) for all segments. The equivalent agreement between radiologists was 0.80 (0.70-0.89). Poorest agreement was observed from ultrasound assessments of the peroneal and tibioperoneal trunk arterial segments., Conclusion: Since agreement between colour duplex scanning and angiography never fell significantly below levels achieved between two radiologists, we conclude that colour duplex ultrasound can be used to assess infrapopliteal artery patency.

The intensity of parasitaemia, degree of anaemia, live body weight gains and blood biochemical changes were measured in two groups of Scottish Blackface sheep infected experimentally with Trypanosoma congolense and allowed either a high (9.9 MJ metabolisable energy (ME) day-1) or a low (6.1 MJ ME day-1) energy intake. It was observed that infected animals on the low energy intake had a longer mean prepatent period, but following patency they developed more severe anaemia and greater growth retardation than those on the high energy intake. Both infected groups exhibited significant reductions in serum total lipids, phospholipids, plasma cholesterol and albumin. However, these changes were more severe in the animals on the low energy intake than in those on the high energy intake. It was concluded that adequate energy nutrition enhances the ability of infected animals to withstand the adverse effects of infection, by promoting body weight gains and moderating the severity of the pathophysiological changes associated with ovine trypanosomosis.

The intensity of parasitaemia, degree of anaemia, blood biochemical changes and live weight gains were measured in two groups of Scottish Blackface sheep infected experimentally with bloodstream forms of Trypanosoma congolense and given either a high or a low protein diet. It was observed that infected animals on a high protein diet tended to develop a higher intensity of parasitaemia than those on a low protein diet. Both groups of infected sheep exhibited similar degrees of anaemia, but the erythropoietic activity, as judged by the increase in mean corpuscular volume and appearance of normoblasts in the circulation, was significantly greater in animals on a high protein diet. The infected animals on a high protein diet gained weight at a similar rate to their uninfected controls, while those on a low protein diet gained significantly less than their controls between 0 and 70 days after infection. Following treatment with the trypanocidal drug isometamidium chloride, both infected groups recovered from the anaemia. However, the rate of recovery was faster in animals on a high protein diet than in those on a low protein diet. It was concluded that high protein intake ameliorates the adverse effects arising from infection, as assessed by the severity of anaemia and weight changes, and also enhances the rate of recovery following chemotherapy.