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Background: The UK Multicentre Aneurysm Screening Study (MASS) showed a 44% reduction in AAA-related mortality after 4 years and predicted an increased number of deaths prevented in the longer term. We aim to compare the 5 and 13 years benefit from aneurysm screening in the Huntingdon Aneurysm screening programme., Methods: Incidence and mortality of ruptured AAA (RAAA) after 5 and 13 years of screening in a population based aneurysm screening program., Results: Five years of screening resulted in a reduction in the incidence of RAAA of 49% (95% CI: 3-74%). Nine out of 11 ruptures in the invited group did not survive (mortality 82%; 95% CI: 48-98%) compared to 38 non-survivors from 51 ruptures in the control group (mortality 75%; 95% CI: 60-86%). Five years of screening resulted in an RAAA-related mortality reduction of 45% (95% CI: -15 to 74%). After 13 years of screening the incidence of RAAA was reduced by 73% (95% CI: 58-82%). Twenty-one out of 29 ruptures in the invited group did not survive (mortality 72%; 95% CI: 53-87%) compared to 64 non-survivors from 82 ruptures in the control group (mortality 78%; 95% CI: 68-86%). Thirteen years screening resulted in a reduction of mortality from RAAA of 75% (95% CI: 58-84%). The number needed to screen to prevent one death reduced from 1380 after 5 years to 505 after 13 years. The number of elective AAA operations needed to prevent one death reduced from 6 after 5 years to 4 after 13 years., Conclusion: AAA screening becomes increasingly beneficial as screening continues over the longer term. Benefits continue to increase after screening has ceased.

Objective: Whole body hypoperfusion and lower torso ischaemia-reperfusion contribute to post-operative organ dysfunction in patients undergoing repair of ruptured abdominal aortic aneurysm (AAA). Serum lactate and base deficit are markers of tissue ischaemia and are used to assess the adequacy of resuscitation. This study examines the prognostic value of immediate post-operative levels of serum lactate and base deficit in ruptured AAA., Methods: Thirty patients (24 men and 6 women of median age 74, range 51-85, years) who survived to at least 12h after ruptured AAA repair were studied retrospectively. The relationship between immediate post-operative lactate, base deficit and mortality was determined., Results: Fifteen patients (50%) died, all from organ failure. An elevated lactate (>2.1 mmol/l) and base deficit (<-2 mmol/l) were present in 20 (67%) and 27 (90%) patients, respectively. Lactate (p<0.001) and base deficit (p=0.003) were significantly higher in non-survivors compared with survivors. Lactate (p=0.021) and base deficit levels (p=0.028) were independently significant for predicting mortality and a significant interaction existed between lactate and base deficit levels for predicting mortality (p=0.027). The sensitivity and specificity of lactate > or =4.0 mmol/l was 13 of 15 (87%) and 12 of 15 (80%), respectively, and base deficit < or =-7 mmol/l was 12 of 15 (80%) and 12 of 15 (80%), respectively. The likelihood ratios for a positive result with the defined cut-off values for lactate and base deficit were 4.3 and 4.0, respectively. Lactate > or =4.0 mmol/l and base deficit or =-7 mmol/l were associated with a 4% probability of death., Conclusion: These data demonstrate that an immediate post-operative serum lactate > or =4.0 mmol/l and base deficit < or =-7 mmol/l are good predictors of outcome after ruptured AAA repair. The prognostic value of these simple and inexpensive tests require corroboration in a larger prospective study.

Perioperative hemorrhage is one of the principal causes of death in patients with ruptured abdominal aortic aneurysm (AAA). This study examines perioperative coagulation and fibrinolysis in patients undergoing ruptured AAA repair complicated by coagulopathy. Eight patients (8 men of median age 74, range 69-87, years) who developed clinical and laboratory evidence of coagulopathy during attempted repair of ruptured infrarenal AAA were prospectively studied. Platelet count, fibrinogen, clotting times, prothrombin fragment (PF) 1+2, and tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) activities were measured preoperatively, immediately before, and 5 min and 24 hr after aortic declamping. Six patients died, three intraoperatively, one within 24 hr, and two in the late postoperative period. All patients had thrombocytopenia and prolonged clotting times intraoperatively with evidence of increased thrombin generation (as demonstrated by elevated PF 1+2). Five patients had increased systemic fibrinolysis (as demonstrated by elevated t-PA activity) preoperatively and/or before aortic declamping and all of these patients died. Three patients had perioperative inhibition of systemic fibrinolysis (as demonstrated by elevated PAI activity) and two survived. These data demonstrate that coagulopathy in ruptured AAA repair may be associated with a hyperfibrinolytic state. Further research is required to determine if (a) a causal relationship exists between hyperfibrinolysis and coagulopathy and (b) whether antifibrinolytic agents can improve outcome if targeted at this group of patients.

Objective: von Willebrand factor (vWF) is essential for the formation of platelet aggregates at sites of vascular endothelial cell (EC) injury. Peri-operative thrombocytopenia is associated with poor outcome in ruptured abdominal aortic aneurysm (AAA) repair. This prospective study examines the relationship between vWF and platelet count (PC) in ruptured AAA repair., Methods: plasma vWF antigen, PC and C-reactive protein (CRP) were measured pre-operatively, and immediately before and 5 min after aortic clamp release, and on post-operative days 1 and 2 in 20 patients (18 men and 2 women of median age 74, range 63-86, years) with ruptured AAA., Results: elevated vWF was present in 13 (65%) patients pre-operatively, and 14 of 16 (88%) survivors at 24 h post-operatively. All patients demonstrated an intra-operative fall in vWF. There was no significant difference in vWF levels between survivors and non-survivors. PC was below the normal range in 8 (40%) patients pre-operatively and all patients at 24 h. Eighteen (90%) patients demonstrated an intro-operative fall in PC. PC was significantly lower in non-survivors pre-operatively (p=0.007), immediately before (p=0.009) and 5 min (p=0.009) and 24 h (p=0.02) after clamp release. There was a significant positive correlation between vWF and PC pre-operatively (r= +0.48, p=0.033), and immediately before (r= +0.47, p=0.044) and 5 min after clamp release (r= +0.5, p=0.043). There was a significant positive correlation between peak vWF level and the greatest fall in PC (r= +0.65, p=0.006). There was a significant negative correlation between vWF and CRP and operative blood loss; and between PC and CRP, operative blood loss and aortic clamp time., Conclusions: these data demonstrate that EC activation, the acute phase protein response, operative blood loss and aortic clamp time all contribute to the peri-operative fall in PC in patients with ruptured AAA. The peri-operative fall in circulating levels of vWF and PC may represent consumption secondary to macro- and microvascular thrombus formation. The resultant procoagulant state may partly explain the association between low PC and poor outcome in ruptured AAA.

Background: ruptured abdominal aortic aneurysm (AAA) is associated with inhibition of systemic fibrinolysis. Hypofibrinolysis is a risk factor for ischaemic myocardial injury, one of the commonest complications of ruptured AAA repair. Cardiac troponin I (cTnI) is one of the most sensitive and specific marker of myocardial injury currently available., Objective: To examine, for the first time, the relationship between fibrinolytic activity and myocardial injury in patients operated for ruptured AAA., Methods: Twenty patients (18 men and 2 women of median age 74, range 65-86 years) undergoing repair of ruptured AAA were prospectively studied. Plasma tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) activity were measured pre-operatively, immediately before and five minutes following aortic clamp release. Serum cTnI was measured pre-operatively, 6 and 24 h following clamp release. Results cTnI was detectable at one or more sample points in 13 (65%) patients, and in 7 out of 8 patients who suffered major cardiac complications. There was a significant negative correlation between pre-operative t-PA activity and cTnI before operation (r =-0.55, p = 0.01) and 6 h ( r =-0.51, p =0.02) after clamp release. There was a significant positive correlation between pre-operative PAI activity and cTnI before operation (r =+0.50, p =0.03), 6 h ( r =+0.47, p =0.04) and 24 h ( r =+0.50, p =0.03) after clamp release. There was no correlation between pre- and intra-operative hypotension or blood transfusion requirement and cTnI release., Conclusions: Hypofibrinolysis during ruptured AAA repair is associated with the development of peri-operative myocardial injury. The causal mechanisms underlying this state are not clear but treatment of this prothrombotic/hypofibrinolytic diathesis may help to limit myocardial cell necrosis., (Copyright 2001 Harcourt Publishers Limited.)

Background: The influence of gender on the management of coronary artery disease is well documented, but few reports exist regarding the influence of gender on the management of peripheral arterial disease., Objective: The purpose of this study was to examine the influence of gender on selection for and short-term and long-term outcomes of repair of ruptured abdominal aortic aneurysm (RAAA) in a regional vascular surgery unit., Methods: Analysis of the prospectively gathered Lothian Surgical Audit database identified 692 patients (542 male and 150 female) admitted with RAAA between January 1, 1983, and December 31, 1995. Case notes were reviewed for patients who were admitted but not operated on. Operative mortality was defined as death within the same hospital admission. Long-term survival data were obtained from the General Register Office (GRO1 records) through record linkage by the Information and Statistics Division of the National Health Service of Scotland., Results: A total of 542 men (78%; median age, 72 years; age range, 46-93 years) and 150 women (22%; median age, 74 years; age range, 55-93 years) were admitted with RAAA (P =.12; Mann-Whitney U test). There was no significant difference in perioperative mortality between men and women. Although women who were not operated on (median age, 81 years; age range, 68-93 years) were significantly (P =.005) older than men who were not operated on (median age, 77 years; age range, 54-93 years), for any given age group, women appeared less likely than men to be offered surgical repair. Long-term survival after successful repair was comparable for the genders., Conclusions: Gender has no influence on either short-term or long-term outcome for patients undergoing operative repair of RAAA. However, women are less likely to be selected for operation than their male counterparts.

Purpose: Elevated levels of soluble tumor necrosis factor receptors (sTNF-Rs) are associated with multiple organ failure and increased mortality rates in critically ill patients. Paradoxically, experimental data suggest exogenous sTNF-Rs may improve outcome in patients who undergo elective abdominal aortic aneurysm (AAA) repair. This study examines, for the first time, changes in sTNF-R levels during repair of ruptured and nonruptured AAA., Methods: Sixteen patients who underwent surgical procedures for ruptured AAA and 10 patients who underwent surgical procedures for nonruptured AAA were studied. Levels of sTNF-Rs p55 and p75 were measured before the operation and immediately before and 5 minutes, 6 hours, and 24 hours after aortic clamp release., Results: When compared with nonruptured AAA, levels of sTNF-R p55 were significantly higher in ruptured AAA 5 minutes (P <.02) and 24 hours after aortic clamp release (P <.05). Levels of sTNF-R p75 were significantly higher in ruptured AAA before (P <.05), during (P <.001), and after the surgical procedure (P <.01). Six hours after aortic clamp release, sTNF-R p75 levels were significantly higher in nonsurvivors of ruptured AAA when compared with survivors (P <.05) and patients who underwent surgical procedures for nonruptured AAA (P <.01)., Conclusion: Ruptured AAA repair is associated with increased sTNF-R expression. Furthermore, elevated levels of sTNF-R p75 are associated with increased postoperative mortality rates.

Penetrating atheromatous ulcers of the aorta are increasingly recognized as a distinct entity. Although their natural history remains ill-defined, such ulcers may lead to pseudoaneurysmal formation, dissection, rupture, or embolization. Given the morbidity associated with open repair, endovascular repair of penetrating atheromatous ulcers may be the treatment of choice. Although stent-graft replacement of acute aortic dissections has recently been described, endovascular repair of penetrating thoracic aortic ulcers has not previously been reported. We report two cases of successful endovascular repair of penetrating atheromatous ulcers that previously ruptured.

Objective: The objective of this study was to examine patterns of referral, management, and outcome of patients with ruptured abdominal aortic aneurysm (RAAA) within the catchment area of this regional vascular unit (RVU)., Methods: Referral, management, and outcome data regarding 972 consecutive patients admitted to the hospital or certified deceased in the community because of RAAA between January 1, 1989, and December 31, 1995, were retrieved from prospectively gathered computerized national and local databases., Results: Of 381 (39.2%) patients admitted to this unit, 316 (82.9%) underwent surgery, and of those, 188 (59.5%) survived. There was no significant difference in overall mortality between patients who were admitted directly to this unit (152 of 310, 49%) and those who were transferred from elsewhere (41 of 71, 58%). Surgical patients traveled significantly farther to the RVU than nonsurgical patients (P <.001), but there was no significant difference in traveling distance between surgical patients who survived and those who did not. Of 372 (38%) patients who were admitted to other units and not transferred, 24 (6.4%) underwent surgery and 14 (3.8%) survived. Of 972 patients, the overall community mortality from RAAA was 770 (79%)., Conclusion: Transferring patients from outlying units did not appear to prejudice operative outcome in this RVU. However, less than half of all RAAA patients were transferred, and only a small minority of those not transferred underwent surgery. Although the overall community mortality from RAAA was similar to that reported in earlier studies from other regions and countries where centralization has not occurred, centralization of vascular surgical services may be associated with an inappropriately low operation and survival rate for those patients who are not transferred to the regional center. The effect of centralization on the community outcome of emergent vascular surgical conditions requires further investigation.

Aim: Aortic compliance as measured by the pressure-strain elastic modulus (Ep) and stiffness (beta), may allow a more precise estimate of rupture risk. The aim of this study was to determine the relationships between compliance, maximal aneurysm diameter and growth rate., Methods: Sixty abdominal aortic aneurysm patients of median age 73 years, were studied. Growth rate was derived from repeat ultrasound scans obtained over a median period of 21 months (range 6-48). At the end of follow-up, patients underwent measurement of maximum aortic diameter, Ep and beta using the Diamove echo-tracking system., Results: Growth rate correlated positively (r = 0.6, P < 0.01) with maximum diameter on entry to the study There was a positive correlation between mean arterial pressure and Ep (r = 0.3, P = 0.03), but not between mean arterial pressure and beta (r = 0.8, P = 0.61). A positive correlation was found between final maximum diameter and Ep (r = 0.22, P = 0.04) but not beta (r = 0.16, P = 0.11). There was no significant relationship between growth rate and Ep or beta., Conclusion: Large aneurysms tended to be less compliant. Within a population of abdominal aortic aneurysm of similar maximum diameter there was a 10-fold variation in Ep and beta. Compliance and growth rate were not related. If aortic compliance is related to risk of rupture then this predictive information is likely to be largely independent of that currently obtained from size and growth rate.

Introduction: The risks and benefits of operating on patients with ruptured thoracoabdominal aortic aneurysm (TAAA) have not been defined. The aim of the present study is to report this unit's experience with operations performed for ruptured TAAA over a 10-year period., Methods: Interrogation of a prospectively gathered computerised database., Patients: Between 1 January 1983 and 30 June 1996, 188 consecutive patients with TAAA were operated on, of whom 23 (12%) were operated for rupture., Results: There were nine survivors (40%). Patients whose preoperative systolic blood pressure remained above 100 mmHg were significantly more likely to survive (4/8 vs. 13/15, p = 0.03 by Fisher's exact test). Survival was also related to Crawford type: type I (two of three survived); II (none of six); III (two of six); and IV (five of eight). All non-type II, non-shocked patients survived operation. Survivors spent a median of 28 (range 10-66) postoperative days in hospital, of which a median of 6 (range 2-24) days were spent in the intensive care unit. Survivor morbidity comprised prolonged ventilation (> 5 days) (n = 3); tracheostomy (n = 1); and temporary haemofiltration (n = 2). No survivor developed paraplegia or required permanent dialysis., Conclusions: Patients in shock with a Crawford type II aneurysm have such a poor prognosis that intervention has to be questioned except in the most favourable of circumstances. However, patients with types I, III and IV who are not shocked on presentation can be salvaged and, where possible, should be transferred to a unit where appropriate expertise and facilities are available.

Background: This study reviews the results of infrarenal abdominal aortic aneurysm (AAA) surgery over 21 years (1 January 1976 to 31 December 1996)., Methods: A prospectively gathered database was analysed., Results: Infrarenal AAA repair was performed in 1515 patients: 492 (32.5 per cent) had elective repair of an asymptomatic AAA; 194 (12.8 per cent) had elective repair of a symptomatic AAA; 156 (10.3 per cent) had emergency repair of a symptomatic non-ruptured AAA; and 673 (44.4 per cent) had surgery for a ruptured AAA. The 30-day and/or same admission mortality rates were 6.1, 5.8, 14.1 and 37 per cent respectively. Operative mortality increased in all four groups over the study interval, although this only attained statistical significance in patients having elective repair of a symptomatic, non-ruptured AAA. There was a significant increase in the age of patients undergoing elective repair of an asymptomatic AAA, but not in the other three groups. There was also a significant increase in the proportion of straight 'tube' grafts inserted in all four groups., Conclusions: It remains the minority of patients who have elective operation before the onset of symptoms and/or rupture. Despite anaesthetic and surgical specialization, the results of AAA repair have not improved over the past two decades. Operative mortality may be increasing, possibly because of the increasing age and associated comorbidity of the patients presenting to this unit.

Objective: The objective of this study was to determine the diagnostic value of computed tomography (CT) in patients with suspected ruptured abdominal aortic aneurysm., Study Design: The study was an interrogation of a prospectively gathered computerized database., Setting: The study was performed at a regional vascular surgery unit., Subjects: Six hundred fifty-two consecutive patients were admitted to this unit with suspected ruptured abdominal aortic aneurysm between January 1, 1989, and December 31, 1996. Seventy-four patients (11.3%) in whom the diagnosis was in doubt on clinical grounds alone underwent urgent CT. A total of 47 men and 27 women with a median age of 73 years (range, 52 to 86 years) were evaluated., Main Outcome Measures: CT and operative findings were compared., Results: CT correctly diagnosed rupture in 22 of 28 patients who underwent operation and correctly excluded rupture in 30 of 39 patients who underwent operation. The sensitivity and specificity of CT when compared with operative findings were therefore 79% and 77%, respectively., Conclusions: These data indicate that CT has little additional diagnostic value. If in the opinion of an experienced vascular surgeon rupture cannot be excluded on clinical grounds alone, and the patient has no medical contraindications to abdominal aortic aneurysm repair, then the patient should be taken directly to the operating department.

Background: The operative mortality rate for elective repair of asymptomatic abdominal aortic aneurysm (AAA) is falling but the fate of patients with ruptured AAA may have changed little over the past decade., Methods: This study was an analysis of a prospectively gathered computerized database., Results: In the 12 years to 31 December 1994, 1144 patients underwent (attempted) repair of AAA. In 514 patients (44.9 per cent) who had an operation for ruptured AAA there was no significant change in the mean age, male:female ratio (418:96), or operative mortality rate (35.0 per cent) over the interval of the study. Forty-seven patients died before reaching the operating theatre, giving an 'intention to operate' mortality rate of 40.5 per cent. A further 68 patients (10.8 per cent of all patients who presented with a ruptured AAA) were not offered operation because of poor medical condition (n = 34) or extreme age (n = 34); three patients refused operation. A greater proportion of patients had surgery between 1989 and 1994 (276 of 323, 85.4 per cent) than between 1983 and 1988 (238 of 309, 77.0 per cent) (P < 0.01, chi2 test)., Conclusion: The proportion of aneurysms operated on for rupture in this unit remains high (almost 50 per cent). The results of surgery for ruptured AAA have not improved in the past 12 years.

Endothelial cell activation as an early response to hypovolaemic shock may be important in the pathogenesis of coagulopathy and multiple organ failure after aortic aneurysm rupture. The aim of this study was to determine whether any evidence could be found of changes in endothelial cell ultrastructure in patients undergoing operation for ruptured aneurysm and to establish a model for future studies of endothelial cells in these patients. At the start of operation, fat samples from the anterior abdominal wall were taken from five patients with ruptured abdominal aortic aneurysms and in an identical fashion from five control patients undergoing elective surgery. Endothelial cells lining capillaries were examined by transmission electron microscopy. Photomicrographs were taken of all capillaries present and these were assessed blindly by three independent observers. When compared with controls it was found that the luminal surface of the endothelial cells in patients with aneurysm rupture was more convoluted, with more frequent processes projecting into the lumen of the capillary. Budding of the luminal surface of the endothelial cell was seen in 11 of 45 capillaries in the rupture group and in none of 44 capillaries in the control group (P < 0.005). Budding was seen in at least one capillary of all five patients presenting with rupture but in none of the control group (P < 0.05). In conclusion, at the ultrastructural level there are changes within endothelial cells in capillaries at an early stage after ruptured abdominal aortic aneurysm.

Purpose: The purpose of this study was to determine the relationship between admission and postoperative platelet count (PC) and mortality and morbidity rates after emergency surgery for ruptured abdominal aortic aneurysm (AAA)., Methods: We performed a case record review of 65 consecutive patients admitted with ruptured AAA., Results: Five patients did not undergo operation because of poor clinical condition, 12 patients died at operation, 13 patients died after operation, and 35 patients survived (operative mortality rate of 58%). Fifteen patients had an admission PC of less than 150 x 10(9)/L, of whom 14 (93%) died; 27 patients had an admission PC of 150 to 250 x 10(9)/L, of whom 8 (30%) died; and 18 patients had an admission PC of greater than 250 x 10(9)/L of whom 3 (17%) died. At the end of operation 29 patients had a PC of less than 100 x 10(9)/L, of whom 13 (45%) died, 20 (69%) had development of multiorgan failure (MOF), and 6 (21%) required relaparotomy for bleeding complications. By contrast, all 19 patients having a PC of 100 x 10(9)/L or greater at the end of the operation survived, three (16%) had development of MOF, and none required further surgery for bleeding. There was a significant inverse correlation between PC at the end of the operation and the number of postoperative days spent on a ventilator, in the intensive therapy unit, and in hospital. After operation, 15 patients had development of thrombocytosis (PC > 400 x 10(9)/L), of whom 10 had development of deep venous thrombosis and 8 had development of pulmonary embolism. There were no deep venous thromboses or pulmonary embolisms in patients who did not have development of a postoperative thrombocytosis., Conclusions: There is a direct correlation between PC on admission to the hospital and death after emergency repair of ruptured AAA. Thrombocytopenia at the end of the operation is associated with a high risk of morbidity from continuing hemorrhage or MOF. The development of postoperative thrombocytosis is associated with a high risk of thromboembolic complications. PC provides a simple marker of outcome in patients diagnosed with and undergoing operation for ruptured AAA.

Long-term survival was assessed after the repair of non-ruptured (n = 311) and ruptured (n = 227) abdominal aortic aneurysm. Follow-up was 94.2 per cent complete, and the overall survival rate at 8 years was 43.6 per cent. There was no significant difference in 8-year survival rates between patients with non-ruptured (45.2 per cent) and ruptured (40.5 per cent) aneurysms. The survival curves were also compared with that for an age- and sex-matched population derived from Scottish Home and Health Department data.