Cytokine pattern in aneurysmal and occlusive disease of the aorta.

BACKGROUND: Prominent inflammatory infiltrates of macrophages and T-lymphocytes are found in both aortic occlusive disease (AOD) and abdominal aortic aneurysms (AAA). These cells secrete different cytokines that might affect matrix turnover through modulation of matrix metalloproteinase expression. A different cytokine pattern might account for the evolution of AOD vs AAA. MATERIALS AND METHODS: Six different cytokines were examined to determine whether AOD and AAA could be characterized by unique cytokine patterns. AOD (n = 8) and AAA (n = 8) tissues were collected and serially treated with salt, dimethyl sulfoxide, and urea buffers to extract the soluble matrix or cell-bound cytokines. Levels of IL-1 beta, TNF-alpha, IL-10, IL-12, and IFN-gamma were measured by immunoenzymatic methods. Additionally, RNA levels of IL-12 and IFN-gamma were measured. RESULTS: AAA tissue contained higher levels of IL-10 compared to AOD tissue (P < 0.05). Higher levels of the proinflammatory cytokines IL-1 beta, TNF-alpha, and IL-6 were found in AOD (P < 0.05). mRNA levels of IL-12 and IFN-gamma did not differ between the diseases. Aortic tissues contained large amounts of matrix or cell-bound cytokines. CONCLUSIONS: AAA is characterized by greater levels of IL-10 while IL-1 beta, TNF-alpha, and IL-6 are higher in AOD. Targeted deletion of these cytokines in animal models might help in identifying their role in the progression of AAA.     

Incision and abdominal wall hernias in patients with aneurysm or occlusive aortic disease

INTRODUCTION: Patients undergoing midline incision for abdominal aortic reconstruction appear to be at greater risk for postoperative incision hernia compared with patients undergoing celiotomy for general surgical procedures. Controversy exists as to whether incidence of abdominal wall hernia and increased risk for incision hernia is higher in patients with abdominal aortic aneurysm (AAA) than in patients operated on because of aortoiliac occlusive disease (AOD). We conducted a prospective multi-institutional study to assess frequency of incision hernia after aortic surgery through a midline laparotomy and of previous abdominal wall hernia. METHODS: Patients with AAA (n = 177) or AOD (n = 82) from three major institutions were prospectively enrolled in the study and examined. Data collected included demographic data, cardiopulmonary risk factors, smoking status, history of previous or current abdominal wall hernia (incision, inguinal, umbilical, femoral), previous midline incision, suture type, and postoperative complications. At a minimum of 6 months after laparotomy, patients were evaluated clinically for a new incision hernia. Differences were tested with the unpaired t test, X(2) test, or Fisher exact test, and multiple logistic regression was used to control for confounding variables. RESULTS: Mean follow-up of the cohort was 32.8 +/- 2.3 months. Rate of abdominal wall hernia and inguinal hernia in patients with AAA versus AOD was 38.4% versus 11% (P =.001) and 23.7% versus 6.1% (P =.003), respectively. Rate of postoperative incision hernia in patients with AAA was 28.2%, and in patients with AOD was 11.0% (P =.002). Adjusting for age, smoking, chronic obstructive pulmonary disease, body mass index, diabetes, bowel obstruction, and suture type, patients with AAA had almost a ninefold risk for postoperative incision hernia formation (odds ratio [OR], 8.8; P =.0049). CONCLUSION: Compared with patients with AOD, patients with AAA have a higher frequency of abdominal wall hernia and inguinal hernia, and are at significant increased risk for development of incision hernia postoperatively. The higher frequency of hernia formation in patients with AAA suggests the presence of a structural defect within the fascia. Further studies are needed to delineate the molecular changes of the aorta and its relation to the abdominal wall fascia.     

Current results of elective aortic reconstruction for aneurysmal and occlusive disease

Decisions to resect small aortic aneurysms or employ non-operative treatment for aorto-iliac occlusive disease must depend on current rather than historical surgical results. To assess current morbidity and mortality, we reviewed 200 consecutive aortic resections in two groups of patients treated from 1981 to 1989: those undergoing elective aortofemoral bypass for occlusive disease (AFB, no. 100) or resection of infrarenal abdominal aortic aneurysms (AAA, no. 100). Indications for AFB included claudication (54%), rest pain (32%), and gangrene (13%). AAA size ranged from 3 to 14 cm (mean 6.5 +/- 2.4 cm); 45% presented with abdominal or back pain. Patients undergoing AFB were younger (AFB 61.5 +/- 10 years vs AAA 68.7 +/- 8.9 years) with a higher incidence of some atherosclerotic risk factors, diabetes mellitus 30% vs 10%, tobacco use 77% vs 49%, hyperlipidemia 21% vs 7%; p less than 0.001). Coronary artery disease (CAD) was more prevalent in AAA patients (49% vs 34%; p less than 0.001). Postoperative mortality was not different in occlusive or aneurysmal disease (3% AFB vs 2% AAA), nor was the occurrence of serious complications such as myocardial infarction (2% vs 1%) or pulmonary embolism (2% vs 3%). Improvements in patient selection, perioperative care and surgical technique have lowered the mortality of elective aortic surgery. Given the current standard of care, an aggressive approach to AAA even in high risk patients is appropriate. The low morbidity of AFB for occlusive disease mandates a critical appraisal of less effective nonoperative therapies.     

Neutrophil chemotaxis and neutrophil elastase in the aortic wall in patients with abdominal aortic aneurysms.

To test the hypothesis that elastin-derived peptides (EDP) from human aortic tissue may be chemotactic for inflammatory cells, we studied the chemotaxis of neutrophils and monocytes to EDP derived from abdominal aortic aneurysm (AAA), aortic occlusive disease (AOD), and control aortas. In addition, we determined if neutrophils deliver neutrophil elastase to the aorta in vivo by staining for neutrophil elastase (NE) throughout the course of abdominal aortic aneurysms with the monoclonal antibody to human NE. EDP from AAA, AOD, and control tissue demonstrated significant chemotactic activity for both neutrophils and monocytes. All neutrophils had a greater attraction to EDP from AAA tissue compared to AOD and control aorta. Neutrophils from AAA patients were more attracted to EDP of AAA tissue than were neutrophils of AOD or control patients attracted to their respective aortic EDP. Neutrophil elastase stained positive in the adventitia and thrombus throughout the course of the aneurysm, but was not found in the intima, media, or plaque of the aorta.     

Abdominal aortic aneurysm: association between haptoglobin phenotypes, elastase activity, and neutrophil count in the peripheral blood

To investigate the role of genetic factors on susceptibility to atherosclerotic arterial disease, the influence of haptoglobin phenotypes (Hp) on serum elastase activity, neutrophil count, and elastin concentration in the aorta was measured in patients with abdominal aortic aneurysm (AAA; n=52) and aortoiliac atherosclerotic occlusive disease (AOD; n=37). Findings (serum elastase activity, peripheral blood neutrophil count) were compared to a control group (CG) of 37 subjects without atherosclerosis. Hp phenotyping performed by starch-gel electrophoresis produced a haptoglobin-hemoglobin complex of three phenotypes: Hp1-1, Hp2-2, and Hp2-1. Distribution of Hp phenotypes was similar in the three study groups (AAA, AOD, CG). Significant increases in serum elastase activity and neutrophil count was measured in Hp2-1 phenotype of AAA patients. Although the aorta wall of aneurysm patients contained less (p<0.001) elastin than that of AOD patients, no significant difference of aorta elastin concentration between the three Hp phenotypes, including Hp2-1, was measured. The postulated association of AAA susceptibility with Hp2-1 phenotype was supported by the study data that demonstrated an increase in serum elastase activity in patients undergoing AAA repair.     

Impaired Fas-induced apoptosis of T lymphocytes in patients with abdominal aortic aneurysms

OBJECTIVE: Homeostasis of the immune system is maintained by apoptotic elimination of potentially pathogenic autoreactive lymphocytes. Emerging evidence shows that Fas-mediated apoptosis is impaired in activated lymphocytes from patients with autoimmune disease. The aim of this work was to assess apoptosis mediated by the cell death receptor Fas in peripheral T lymphocytes from patients with abdominal aortic aneurysms (AAA). METHODS: The apoptotic pathway was triggered by anti-Fas monoclonal antibodies in cultured and activated peripheral T-cell lines from 20 AAA patients with control groups of 15 patients with aortic atherosclerotic occlusive disease (AOD) and 25 healthy individuals. Cell survival and death (apoptosis) rate were assessed. RESULTS: Cross-linkage of Fas receptor exerted a strong apoptotic response on T cells from AOD patients and healthy controls, but a much less pronounced effect on T cells from AAA patients. The evaluation of cell survival rate showed a significantly higher percentage in AAA group (98.9% +/- 10.3%) than in the AOD subjects (58.9% +/- 15.2%) or the healthy group (59.4% +/- 12.9%; P < .001). Apoptosis assessment by annexin V and propidium iodide staining and flow cytometry showed similar results. The defect in AAA group was not due to decreased Fas expression, since Fas was expressed at normal levels. Moreover, it specifically involved the Fas system because cell death was induced in the normal way by methylprednisolone. Complementary DNA sequencing identified no causal Fas gene mutation, but two silent single nucleotide polymorphisms with higher frequency were found in the AAA group. CONCLUSIONS: Fas-induced apoptosis in activated T cells from AAA patients is impaired. This may disturb the normal down-regulation of the immune response and thus provide a new insight into possible mechanisms and routes in the pathogenesis of AAA.     

Systemic dilation diathesis in patients with abdominal aortic aneurysms: a role for matrix metalloproteinase-9?

INTRODUCTION: Accumulating evidence suggests that patients with abdominal aortic aneurysm (AAA) suffer from a systemic dilating condition affecting all arteries. Matrix metalloproteinases (MMPs) and their natural inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), appear to be involved in aneurysm formation, as evidenced by increased aortic tissue MMP activity and plasma MMP levels in patients with AAA. Hypothesizing that an imbalance in plasma MMP/TIMP level might be associated with a systemic dilation diathesis, we studied mechanical vessel wall properties of non-affected arteries of patients with either AAA or aorto-iliac obstructive lesions in association with plasma MMP-9 and TIMP-1 levels. METHODS: Twenty-two patients with AAA and 12 with aorto-iliac occlusive disease (AOD) were included. Diastolic diameter (d) and distension (Deltad) were measured at the level of the common carotid artery (CCA) and suprarenal aorta (SA) using ultrasonography. Distensibility (DC) and compliance (CC) were calculated from d, Deltad and brachial pulse pressure. Plasma MMP-9 and TIMP-1 were determined with specific immunoassays. RESULTS: The average (+/-SD) age was 72.3+/-5.6 and 65.0+/-8.2 years for the AAA and AOD patients, respectively, (P=0.005). CCA diameter was 9.1+/-1.3mm in AAA patients and AOD 7.8+/-1.4mm in AOD patients, P=0.009. This difference persisted after correction for age. Plasma MMP-9 and TIMP-1 did not differ significantly between AAA and AOD patients. In the total 34 patients, the MMP-9/TIMP-1 ratio was correlated inversely with distensibility (r=-0.74, P=0.002) and to compliance (r=-0.58, P=0.024) of the suprarenal aorta. CONCLUSIONS: The CCA diameter was larger in AAA patients compared to AOD patients. MMP-9/TIMP-1 ratio was associated with decreased distensibility and compliance of the suprarenal aorta. These data support the idea that AAA patients exhibit a systemic dilation diathesis, which might be attributable to MMP/TIMP imbalances.     

Serum concentrations of elastin-derived peptides in patients with specific manifestations of atherosclerotic disease.

OBJECTIVE: To measure serum concentrations of elastin-derived peptides (S-EDP) in patients with aneurysmal, occlusive and ulcerative manifestations of atherosclerotic disease. MATERIALS AND METHODS: S-EDP concentrations were measured by a competitive enzyme-linked immunosorbent assay in 10 patients with infrarenal aneurysms 5cm in diameter (AAA), 10 patients with distal aortic occlusive disease (AOD), 10 patients with symptomatic carotid stenosis (>or=70%) and plaque ulceration (SCS) and a control group of 10 patients with no similar specific manifestations of atherosclerotic disease (NAM). RESULTS: S-EDP concentrations (median, range) were significantly higher in patients with AAA (42ng/ml, 35-52, p<0.001) and SCS (49ng/ml, 37-60, p<0.001) but not AOD (28ng/ml, 22-38, p=0.240) compared to NAM (26ng/ml, 19-36) patients. CONCLUSION: Increased concentrations of S-EDP were associated with aneurysmal and ulcerative, but not occlusive, manifestations of atherosclerosis.     

The influence of peripheral vascular disease on the carotid and femoral wall mechanics in subjects with abdominal aortic aneurysm

AIM: Aortic and carotid stiffness is elevated in patients with abdominal aortic aneurysm (AAA). Peripheral vascular disease (PVD) frequently coexists with AAA and may further impair the arterial wall mechanics and increase the cardiovascular load. We therefore studied the elastic carotid and muscular femoral biomechanical properties and intima-media thickness (IMT) in this group of patients. METHODS: The elastic indices and IMTs of the common carotid and common femoral arteries were determined in 30 patients with AAA (15 with PVD) with a duplex scanner coupled with a wall tracking system. Fasting plasma creatinine level, glucose and lipid concentrations, and their physiologic variables known to influence the arterial wall mechanics were also assessed. RESULTS: Patients with AAA and PVD have significantly stiffer carotid (Petersen's elastic modulus, 2207 +/- 905 mm Hg versus 1268 +/- 432 mm Hg; P =.001; stiffness index, 22.73 +/- 9.63 versus 12.60 +/- 4.24; P =.001] and femoral (Petersen's elastic modulus, 4906 +/- 4057 mm Hg versus 2599 +/- 1169 mm Hg; P =.043; stiffness index, 49.02 +/- 40.04 versus 26.07 +/- 13.22; P =.044) arteries than subjects with AAA alone. Although patients with PVD have thicker carotid and femoral IMTs, no statistical difference was seen between the two groups. The subjects were matched for age, body mass index, heart rate, systolic and diastolic blood pressures, total vascular risk score, plasma creatinine level, and fasting lipid and glucose concentrations. CONCLUSION: Subjects with PVD and AAA have significantly stiffer carotid and femoral arteries, which may indicate increased cardiovascular load and may account for the highest mortality rate seen in these patients in the UK Small Aneurysm Trial. Therefore, treatment of associated cardiovascular risk factors is important and may have to be tailored on an individual basis according to the findings of the arterial wall mechanics.     

Interleukin-1 beta and tumor necrosis factor-alpha release in normal and diseased human infrarenal aortas.

The presence of chronic inflammatory cells in the adventitia and media of abdominal aortic aneurysms and aortic occlusive disease suggest an immunologic response. The purpose of this study is to determine whether normal or diseased infrarenal aortas liberate the inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta). Twenty-six infrarenal aortic biopsies (5 aortic occlusive disease, 15 abdominal aortic aneurysms, and 6 cadaveric donors) were weighed, minced into small pieces, and incubated in media for 48 hours. Conditioned media was harvested at 48 hours and assayed for IL-1 beta or TNF-alpha with use of an ELISA assay. Comparison of groups was performed with a one-way analysis of variance. The constitutive IL-1 beta produced by abdominal aortic aneurysms was significantly different than that in cadaveric donors (908 +/- 194 pg/ml [SE] vs 100 +2- 30 pg/ml). There was no statistically significant difference between abdominal aortic aneurysms and aortic occlusive disease (908 +/- 194 pg/ml vs 604 +/- 256 pg/ml) or aortic occlusive disease and cadaveric donor (604 +/- 256 vs 100 +/- 30). In time-course studies for the release of IL-1 beta, abdominal aortic aneurysms demonstrated maximal release at 48 hours. IL-1 beta release was augmented by lipopolysaccharide in all categories. A dose response curve demonstrated maximal IL-1 beta release on stimulation with 5 micrograms/ml LPS. Constitutive TNF-alpha production was low, ranging from 13 +/- 1.5 pg/ml in cadaveric donor, to 20 pg/ml in aortic occlusive disease, and 24 +/- 11 pg/ml in abdominal aortic aneurysms. There was no augmentation in TNF-alpha with lipopolysaccharide.(ABSTRACT TRUNCATED AT 250 WORDS)     

Screening for abdominal aortic aneurysm and occlusive peripheral vascular disease in Japanese residents

To evaluate the prevalence of abdominal aortic aneurysm (AAA) and occlusive peripheral vascular disease (PVD) in Japanese residents, and to examine the correlations between these diseases and the risk factors of atherosclerosis, 348 residents of a village in central Japan aged between 60 and 79 years were screened. The screening for AAA was performed using ultrasonography (US) and that for PVD was performed by palpation and Doppler US. No AAA was found, and a right common iliac arterial aneurysm was detected in a 79-year-old man (0.3%). The mean diameter of the infrarenal abdominal aorta was 18.7 mm and an abdominal aorta of 25 mm or greater in diameter was seen in 16 participants (4.6%), all of whom need to be followed up. PVD was suspected in two patients (0.6%) with a low ankle brachial pressure index. Of a total of five patients diagnosed or suspected of having a common iliac arterial aneurysm or PVD, four (80%) had at least one risk factor for atherosclerosis. Thus, we conclude that Japanese residents with risk factors predisposing them to atherosclerosis such as hypertension, obesity, abnormal serum lipid levels, and a history of smoking should be selectively screened for AAA and PVD due to the low prevalence of these diseases and from the viewpoint of cost-effectiveness.     

Smooth muscle cell elastase, atherosclerosis, and abdominal aortic aneurysms.

Smooth muscle cells (SMC) were obtained by outgrowth of human aortic explants from abdominal aortic aneurysm (AAA) patients, aortic occlusive disease (AOD) patients, and transplant donors (controls). Specimens were incubated with medium alone or medium with either elastin-derived peptides (EDP, 5 micrograms/mL) or low-density lipoproteins (LDL, 5 micrograms/mL). Elastase activity (ng/mg total protein) was assayed from 4-week-old cultures. Control aortas obtained from patients significantly younger secrete an increased amount of elastase at baseline compared with AOD and AAA patients (p less than 0.05). Elastin-derived peptides caused a significant increase in elastase secretion in all groups. The increase in elastase secretion in response to EDP in AAA patients was significantly higher compared with AOD or control. Low-density lipoprotein had no effect on SMC elastase secretion. These data suggest that (1) aortic SMCs secrete elastase in response to EDP, (2) SMC elastase is age dependent, and (3) AAA SMC secrete an abnormally high amount of elastase compared with AOD and control aortas in response to EDP. Like the neutrophil, the SMC is highly responsive to the degradation products of elastin and in AAA patients secrete significantly increased amounts of elastase in response to the breakdown products of atherosclerosis.     

The influence of collateral vascularisation on haemodynamic performance during abdominal aortic surgery

The extent of periaortic collateral vascularisation has been proposed as a possible mechanism of an altered haemodynamic response to infra-renal aortic cross-clamp in patients undergoing by-pass grafting for aorto-iliac occlusive disease (AOD) compared with patients undergoing abdominal aortic aneurysm (AAA) resection. The haemodynamic responses following clamping, during the clamp time and following clamp release were studied in 18 patients undergoing AAA resection and 12 patients undergoing bypass grafting for AOD. The role of preoperative aortography in predicting cardiovascular performance during aortic vascular surgery was assessed. During the cross-clamp period LVSWI and CI decreased while SVR increased in the AAA group while the AOD group showed an improved CI, stable LVSWI and reduced SVR, which correlated with the extent of periaortic vascularisation on preoperative aortography. Chronic collateral circulation associated with AOD may permit continuous lower extremity perfusion during aortic cross-clamp. The extent of periaortic collateralisation may influence the choice of monitoring techniques and anaesthetic management.     

Cytokines, their genetic polymorphisms, and outcome after abdominal aortic aneurysm repair.

BACKGROUND: Excessive cytokine production has been implicated in the development of organ failure. Polymorphic sites in cytokine genes have been shown to affect levels of production in vitro and may influence cytokine production in vivo. The aims of this study were to determine if cytokines or their genetic polymorphisms were related to outcome after abdominal aortic aneurysm (AAA) repair. METHODS: A prospective study of 135 patients undergoing open AAA repair. Plasma levels of TNF-alpha, IL-1beta, IL-6 and IL-10 were measured 24 h post-operatively and genotypes for the TNF-alpha -308, IL-1beta+3953, IL-6 -174, IL-10 -1082 and IL-10 -592 polymorphisms were determined for each patient. RESULTS: After elective AAA high levels of IL-10 were associated with both prolonged critical care (P<0.001) and hospital stay (P=0.001). The presence of a G allele at the IL-6 -174 locus was associated with a higher incidence of organ failure (P=0.04) and an A allele at TNF-alpha -308 with prolonged critical care stay (P=0.03). After ruptured AAA the development of multi-organ failure was associated with high levels of IL-6 (P=0.01) and TNF-alpha (P=0.04). High TNF-alpha levels were also associated with mortality (P=0.01). CONCLUSION: Post-operative cytokine levels are related to outcome after AAA repair. Cytokine gene polymorphisms may provide a method for determining which patients are at high risk of complications.     

Increased plasma levels of metalloproteinase-9 are associated with abdominal aortic aneurysms

Purpose: Previous investigators have identified disease-specific elevations of metalloelastase-9 (MMP-9) in aneurysm tissue biopsies. We hypothesized that circulating MMP-9 might also be elevated in patients with aneurysms. The purpose of this study was to compare plasma and aortic tissue MMP-9 levels in patients with infrarenal aneurysms (AAAs), patients with symptomatic aortoiliac occlusive disease (AOD), and healthy patients. Methods: A sandwich enzyme-linked immunosorbent assay was used to measure plasma MMP-9 in patients with AAA (n = 22; mean age, 72.7 years), with AOD (n = 9; mean age, 60.5 years), and without disease (n = 8; mean age, 35.3 years). The MMP-9 levels also were measured in 48-hour supernatants of organ culture tissue explants from patients with AAA (n = 10; mean age, 66.2 years) and AOD (n = 5; mean age, 50.4 years) and organ donors (n = 7; mean age, 48.1 years). The results were reported as the mean ± the standard error of the mean and analyzed with analysis of variance with multivariate regression. Results: The plasma MMP-9 levels were significantly higher in the patients with AAA (85.66 ng/mL ± 11.64) than in the patients with AOD (25.75 ng/mL ± 4.159; P < .001) or the healthy patients (13.16 ng/mL ± 1.94; P < .001). No significant difference in plasma MMP-9 levels between patients with AOD and healthy patients was identified. The patients with multiple aneurysms had significantly higher levels of plasma MMP-9 than did the patients with an isolated AAA (134.68 ng/mL ± 17.5 vs 71.03 ng/mL ± 10.7; P < .04). In organ culture, AAA and AOD tissue explants produced significantly higher levels of MMP-9 (3218.5 ng/gm ± 1115.2 and 1283.1 ng/gm ± 310.6 aortic tissue) than did disease-free explants (6.14 ng/gm ± 2.3 aortic tissue; P < .0001). No significant difference in MMP-9 production between AAA and AOD explants was identified. Conclusion: Plasma MMP-9 levels are significantly higher in patients with AAA than in patients with AOD or in healthy volunteers. The patients with multiple aneurysms have higher levels than those patients with an isolated AAA. Organ culture studies suggest that diseased aortic tissue is the source of MMP-9. (J Vasc Surg 1999;29:122-9.)     

Factors associated with development of large abdominal aortic aneurysm in middle-aged men.

OBJECTIVES: To investigate whether any variables in a health-screened population study were associated with later development of large abdominal aortic aneurysms (AAA). SETTING: Malm?, Southern Sweden. MATERIAL AND METHODS: Within the Malm? Preventive Study 22,444 men and 10,982 women were investigated between 1974 and 1991. The mean age at the health screening was 43.7 years. RESULTS: After a median follow-up of 21 years, 126 men and six women (p<0.001) had large AAA that were symptomatic or evaluated for operation (5 cm diameter or more) or had autopsy-verified ruptured AAA. The male group (mean age 47 years) was, because of difference in age (p<0.001) also compared with an age-matched control group. The male patients with AAA showed increased diastolic blood pressure (p<0.007) at the health screening. Smoking predicted the development of AAA (p<0.0001). No difference in forced vital capacity or BMI was seen. Those who were physically inactive (e.g. not walking or cycling to work) had an increased risk of developing AAA (p<0.001). Among the laboratory markers measured, the erythrocyte sedimentation rate did not differ (7.1+/-5.9 vs. 6.4+/-5.7), but cholesterol (6.3+/-1.12 vs. 5.8+/-1.0) (p<0.0001) and triglycerides (1.9+/-0.12 vs. 1.5+/-0.07) (p<0.001) were significantly elevated in these individuals who subsequently developing AAA. The inflammatory proteins alfa-1-antitrypsin, ceruloplasmin, orosmucoid, fibrinogen, and haptoglobulin were increased (p<0.001). CONCLUSION: Male gender, smoking, physical inactivity and cholesterol are significant factors associated with the development of AAA.     

The inflammatory response and its consequence for the clinical outcome following aortic aneurysm repair.

OBJECTIVE: to review published studies on the outcome of the inflammatory response after abdominal aortic aneurysm (AAA) repair. METHODS: a literature search on PubMed was performed. All studies that determined the inflammatory response (cytokine release) after AAA repair were included. The results of the studies and differences between open and endoluminal repair were compared and evaluated. RESULTS: seventeen studies were identified. In most studies the investigated cytokines were TNF-alpha and IL-6. Determination of IL-1 beta, IL-8, TNFsr1 and TNFsr2 were less often performed. TNF-alpha may reflect, but not strictly predict, the clinical outcome in patients with ruptured AAA. IL-6 levels correlate well with the surgical trauma per se. Variations in recorded cytokine release during endovascular AAA repair may depend on the times of blood sampling. CONCLUSION: both open and endovascular AAA repair provoke a cytokine response. This response is greater during open repair than during endovascular aortic aneurysm exclusion.     

Simultaneous coronary bypass and abdominal aortic surgery in patients with severe coronary disease — indication and results

In patients with severe coronary artery disease (CAD) abdominal aortic surgery is still associated with high morbidity and mortality rates. Some patients will present with both symptomatic CAD and large, symptomatic abdominal aortic aneurysms (AAA) or end-stage aortic occlusive disease (AOD) that does not allow for a two-stage procedure. We report a series of 29 patients who underwent simultaneous coronary artery bypass graft surgery (CABG) and abdominal aortic surgery (25 AAA, 4 AOD). In the AAA group there were 23 males and 2 females with a mean age of 68 years (50–80). Sixteen patients presented with severe three-vessel disease. Ten patients had unstable angina. Aortic stenosis or insufficiency was present in two and one patient, respectively. Four patients with three-vessel disease and an ejection fraction below 30% presented with end-stage AOD and critical limb ischemia. Coronary bypass graft surgery was performed first. With the patient still on partial cardiopulmonary bypass, abdominal aortic surgery was carried out. Patients received an average of 3.1 coronary bypass grafts. Additionally, three aortic valves were implanted. Fourteen tube grafts and 15 bi-iliacal or bifemoral bifurcation grafts were placed in the abdominal aortic position. Additional vascular surgery was performed in five patients. Intraoperative management was without complication in all but one patient, who had intraoperative myocardial infarction (AOD group). Hospital mortality was 8% (2/25) in the AAA group. There was however substantial hospital morbidity (52.2%). The mean follow-up is 20.5±2.5 months. The actuarial survival rate at 3 years is 84.9%. It is concluded that combined CABG and abdominal aortic surgery is a reasonable option for patients who present with both severe CAD and symptomatic abdominal aortic disease. The continuation of CPB during aortic surgery may effectively prevent the adverse effects of infrarenal aortic clamping on a failing ventricle.     

Postoperative incision hernia in patients with abdominal aortic aneurysm and aortoiliac occlusive disease: a systematic review.

OBJECTIVES: We conducted a systematic review to determine the incidence of postoperative incision hernia in patients with abdominal aortic aneurysm compared to those with aortoiliac occlusive disease. METHODS: Studies which compared the incidence of postoperative incision hernia in patients with abdominal aortic aneurysm and aortoiliac occlusive disease undergoing midline incision for arterial reconstruction were identified. MEDLINE was searched for articles published between January 1966 and September 2005. RESULTS: Our search identified seven studies including data on 1132 patients, 719 with abdominal aortic aneurysm and 413 with aortoiliac occlusive disease. Pooled analysis demonstrated that patients with abdominal aortic aneurysm had a 2.9-fold increased risk of inguinal hernia (odds ratio 2.85, 95% confidence interval 1.71-4.77, p<0.0001), and a 2.8-fold risk of incisional hernia (2.79, 1.88-4.13, p<0.0001). Adjusting for other known risk factors patients with aortic aneurysm had a 5-fold increased risk of incisional hernia (5.45, 2.48-11.94, p<0.0001). CONCLUSIONS: Patients with abdominal aortic aneurysm appear to have an approximately 3-fold increased risk for both inguinal and postoperative incision hernia compared to patients with aortoiliac occlusive disease. A large multi-centre prospective study is needed to confirm the results of this review.     

Infrainguinal arterial reconstructions with vein grafts in patients with prior aortic procedures: the influence of aneurysm and occlusive disease

PURPOSE: This study assessed whether infrainguinal reconstructions with autogenous vein (IR) performed in patients with prior abdominal aortic aneurysm (AAA) repairs have altered graft patency, compared with those in patients who have undergone prior aortobifemoral bypass grafting procedures (ABF) for aortoiliac occlusive disease. METHODS: From 1979 to 1998, 54 patients with prior aortic reconstructions underwent 64 autogenous single-segment saphenous IRs solely for infrainguinal occlusive disease. Included in this cohort were 30 IRs with an earlier AAA repair and 34 IRs with an earlier ABF repair. During the same period, 1274 patients underwent 1642 autogenous vein lower-extremity bypass grafting procedures (LEB). Lower-extremity native arterial (AAA, n = 6; ABF, n = 11) and vein graft diameters (AAA, n = 6; ABF, n = 6) were determined by means of angiography and duplex ultrasonography, respectively. The three reconstruction groups (AAA, ABF, LEB) were compared. RESULTS: The patients in the three groups were similar in sex, indication for operation, proximal and distal anastomotic site, and number of distal runoff vessels. The cumulative 5-year primary graft patency rate in the AAA group (92% +/- 5%) was significantly higher (P <. 001) than that in the LEB group (63% +/- 2%) and the ABF group (44% +/- 11%). Furthermore, cumulative 5-year primary patency was decreased in the ABF group compared with the LEB group (P =.05). A significant increase in both native arterial (P =.001) and vein graft diameter (P <.05) was demonstrated by using linear regression and a Student t test, respectively, in the AAA group compared with the ABF group. CONCLUSION: These data demonstrate that, compared with those in patients without a previous aortic procedure, IRs in patients with prior AAA repairs have significantly improved graft patency, and IRs in patients with prior ABF reconstructions for aortoiliac occlusive disease have significantly decreased graft patency. Larger arterial diameter and altered vein graft adaptation may contribute to the superior long-term outcomes of IRs in patients with prior AAA repairs.