Paradoxical neutrophil elastase release in endovascular abdominal aortic aneurysm repair

Endovascular repair of abdominal aortic aneurysm potentially avoids problems associated with prolonged aortic cross-clamping that occurs with open repair, but it appears to have its own biologic consequences, which may relate to neutrophil elastase release. Blood samples of consecutive patients undergoing open or endovascular abdominal aneurysm repair were analyzed for neutrophil elastase/alpha(1)-antitrypsin complex and free elastase. Free elastase rose from baseline and fell quickly in open repair patients, returning to baseline by 144 hours. In the endovascular repair group, it continued to increase for up to 144 hours. Bound elastase increased to 24 hours, returning to baseline in endovascular repair patients by 72 hours, but remaining elevated in open repair patients at 144 hours. Open repair patients showed raised elastase/alpha(1)-antitrypsin complex and initial raised free elastase levels. High free elastase levels in endovascular repair patients may reflect less bound elastase and may paradoxically lead to a prolonged inflammatory postoperative response.     

Abdominal aortic aneurysm in normotensive patients: association with angiotensin-converting enzyme gene polymorphism.

OBJECTIVE AND DESIGN: to assess if deletion of the angiotensin-converting enzyme (ACE) gene is a risk factor for abdominal aortic aneurysms (AAAs) in normotensive patients. MATERIALS AND METHODS: ACE gene polymorphism was examined by polymerase chain reaction in 124 subjects with AAA and in 112 control subjects. AAA normotensive patients (group A, n=56) were compared to normotensive control subjects (group B, n =112) and to AAA hypertensive patients (group C, n =68). All subjects enrolled in this study were Caucasian and from central and southern Italy. RESULTS: the distribution of ACE genotypes was: normotensive patients with AAAs (group A): 3 II, 14 ID, 39 DD; normotensive control subjects (group B): 36 II, 48 ID, 28 DD; hypertensive patients with AAAs (group C): 14 II, 32 ID, 22 DD. The DD genotype was more common in group A than in control groups (A vs B p<0.001; A vs C p <0.001). The ID genotype was more common in group A as well (A vs B p <0.05; A vs C p <0.005). CONCLUSIONS: our data suggest a role for ACE I/D gene polymorphism in the pathogenesis of AAA in normotensive patients.     

Prognostic markers in diarrhoea-associated haemolytic-uraemic syndrome: initial neutrophil count, human neutrophil elastase and von Willebrand factor antigen

The observed increase in plasma von Willebrand factor antigen (vWF:Ag) in patients with the haemolytic-uraemic syndrome is presumed to be secondary to endothelial damage, which is a central event in these diseases. As the prognostic value of such changes has not been previously evaluated, vWF:Ag has been measured in plasma from children reported to a national survey of haemolytic-uraemic syndrome. Human neutrophil elastase was also measured, as an initial neutrophilia has been shown to have prognostic value in diarrhoea-associated haemolytic-uraemic syndrome. Despite a significant elevation of plasma vWF:Ag concentration in these patients at presentation, the values did not correlate with the period of thrombocytopenia, the need for dialysis, or outcome. However, children with a poor outcome had significantly greater plasma elastase concentrations compared to those who had a good outcome.     

Abdominal aortic aneurysm screening: recommendations and controversies

Extensive level one evidence supports routine abdominal aortic aneurysm (AAA) screening in men aged 65 to 75 years, because AAAs are highly prevalent in this population. Physical examination is an insensitive means of detection. Ruptured AAAs are costly with respect to quality adjusted life years (QALY) lost and medical expenses. Large scale, randomized trials have demonstrated that AAA screening reduces all AAA-related mortality in the screened population and is cost-effective in mid-term follow-up. AAA screening by ultrasound has many advantages over other accepted medical screening programs in its simplicity in structure and the availability of an inexpensive, portable, and reliable means of screening. Additionally, AAA screening almost entirely avoids the negative consequences associated with other screening programs, including the adverse psychological effects and medical costs associated with false-positive examination results. There are subgroups of at-risk women who might benefit from AAA screening, and this issue should be further studied.     

Abdominal aortic aneurysm: epidemiology,screening and work-up for repair

Abdominal aortic aneurysm (AAA) is a dilatation of the infra-renal abdominal aorta to greater than 3 cm. Population screening is offered to men in the year of their 65th birthday in the UK. Patients with small, asymptomatic AAAs (<5.5 cm) are entered into surveillance programmes and have their cardiovascular risk factors managed aggressively. An AAA ≥5.5 cm diameter, or one which is symptomatic, should be considered for surgical repair to prevent rupture. Aneurysm repair can be undertaken using either an open surgical or endovascular approach; the decision should be tailored to the individual patient and made by the surgeon and patient, with input from a multi-disciplinary team.     

Abdominal aortic aneurysm repair in the over eighties

Between January 1980 and September 1988, 34 octogenarians underwent aortic aneurysm repair. There were 26 men and eight women with a median age of 83 years (range 80-88 years). Twenty underwent 'emergency' repair after presenting with pain and/or collapse: 11 with a retroperitoneal rupture, three with an intraperitoneal rupture and six with an expanding aneurysm. The mortality rate for this group was 35 per cent. During the same period 14 patients had an elective repair and there were no deaths within 30 days. The mean hospital stay for the elective group was 14.2 days compared with 17.0 days for survivors in the emergency group. There was no significant difference in terms of risk factors between those who developed postoperative complications and those who did not. These mortality rates compare favourably with our overall mortality results for elective (4.6 per cent) and emergency (31 per cent) surgery. Those patients over 80 years of age with infrarenal abdominal aortic aneurysms should not be refused surgery on the basis of age alone; each patient should be judged individually.     

Abdominal aortic aneurysm screening in the United States

Abdominal aortic aneurysm (AAA) ruptures account for a high mortality rate in the United States. The Screen for Abdominal Aortic Aneurysm Very Efficiently (SAAAVE) Act in 2007 was implemented to prevent AAA ruptures and to benefit older US males using the Medicare system to initiate nationwide population-based AAA screening using United States Preventative Services Task Force screening criteria. After the first year of implementation, less than 1?% of all eligible Medicare beneficiaries were screened. A grassroots effort in 2009 sought to improve and modify the SAAAVE Act to include more Medicare enrollees through legislation. The largest integrated health systems, such as the Department of Veterans Affairs and Kaiser Permanente, use an electronic medical record to implement their own population-based AAA screening programs. Despite an underutilization of AAA screening across the US, efforts are underway into improving AAA screening programs and the management of small AAAs with clinical trials and prospective studies.     

Abdominal aortic aneurysm repair in the veteran population

Background: The aim of this study was to audit the outcome of elective open aortic aneurysm repair in a veteran hospital to determine whether age ≥80 years influenced the morbidity or mortality. Methods: All elective abdominal aortic aneurysm (AAA) repaired at Greenslopes Private (Repatriation) Hospital between January 1995 and July 2000 were reviewed. Operative details, premorbid condition, postoperative outcomes as well as length of admission were recorded. Patients were grouped according to age as ≥80 years or <80 years. Results: There were 251 open elective AAA (including infrarenal and suprarenal, as well as recurrent AAA) repairs carried out during this period, 64 of which were patients of age ≥80 years. Cardiovascular risks factors did not differ between groups nor did complication rates for patients ≥80 and <80 years of age (19.1 and 19.8%, respectively). Mortality rates were not significantly different between groups (≥80 years: 6.25%; <80 years: 4.8%; P > 0.6). Conclusions: Age ≥80 years should not be an exclusion criteria when contemplating open elective AAA repair.     

Prophylactic effects of neutrophil elastase inhibitor for patients undergoing surgery for thoracic aortic aneurysm: a retrospective study

BACKGROUND: Systemic inflammatory response syndrome (SIRS) can occur after cardiac surgery under cardiopulmonary bypass (CPB), especially thoracic aortic surgery. Several reports have suggested that the earlier neutrophil elastase inhibitor (NEI) is used, the more dramatically the acute lung injury (ALI) following SIRS can be improved. We therefore examined whether prophylactic administration of NEI is effective in treating ALI following SIRS. METHODS: In a retrospective study, 24 patients were divided into a control group and a NEI group, for whom infusion of NEI 0.2 mg x kg(-1) x hr(-1) was started prior to initiation of CPB. We compared PaO2/FIO2 (P/F) ratio, intubation time, ICU stay, and numbers of intubated patients and patients admitted to the ICU between the two groups. We also examined laboratory findings for the two groups related to systemic inflammation and organ function. RESULTS: In the NEI group, P/F ratio tended not to be exacerbated postoperatively, which might have been responsible in part for the finding that intubation time and ICU stay were significantly shorter and ratios of intubated patients and those staying in the ICU were significantly lower in the NEI group. Laboratory findings in the two groups fluctuated similarly. CONCLUSIONS: Prophylactic administration of NEI appears to be useful for achieving early extubation and discharge from the ICU of patients undergoing thoracic aortic surgery.     

Abdominal aortic aneurysm surgery with mechanical support using the Impella microaxial blood pump

A 50-year-old man with an end-stage cardiac failure was referred to our institution for pre-transplantation assessment. An infrarenal aortic aneurysm (diameter 45 mm) was discovered and progressed (up to 59 mm) over a two-month period. Decision to perform aneurysmectomy with the support of an Impella Recover LP50 microaxial blood pump was decided regarding the rapid evolution of the disease. The patient had uneventful cardiac-wise during surgery and postoperative period.     

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 in the patient undergoing cardiac transplantation

In the past 3 years at our institution 130 patients have undergone cardiac transplantation for ischemic cardiomyopathy in 49 (38%), idiopathic cardiomyopathy in 42 (32%), viral cardiomyopathy in 9 (6.9%), pulmonary hypertension in 8 (6%), and graft atherosclerosis in 2 (1.5%). Routine preoperative abdominal ultrasonography was performed on 98 (75%) of these patients with specific visualization of the abdominal aorta in 93 (95%). Abdominal aortic aneurysms (all infrarenal) were found before operation in four patients and only in the subgroup undergoing transplantation for ischemic heart disease (10.5%). They measured 3.4, 4.5, 3.6, and 3.8 cm before transplantation. Periodic evaluation by ultrasonography was carried out after transplantation during the 3-year period of this study. One aneurysm that was initially 3.6 cm increased to 4.0 cm and ruptured 2 months after transplantation. The patient died despite emergent surgery. Aneurysms in three patients who demonstrated rapid aneurysm expansion after transplantation were successfully repaired at 5, 20, and 33 months after transplantation when the lesions reached 5.5, 5.9, and 4.8 cm. A fifth patient with an initially normal (1.5 cm) aorta developed a symptomatic aneurysm of 4.1 cm, which was repaired uneventfully. The average expansion rate of these aneurysms after transplantation was 0.74 +/- 0.15 cm/year. This experience suggests that aneurysms are limited to patients undergoing transplantation for ischemic heart disease. Ultrasound examination may be appropriate for preoperative screening. Careful aortic surveillance after transplantation is important in patients having transplantation for ischemic cardiomyopathy because of the apparent rapid expansion rate compared to aneurysms in the population not receiving transplants.     

Abdominal aortic aneurysm in women: prevalence, risk factors, and implications for screening

OBJECTIVE: Accurate data regarding the prevalence and associated risk factors for aneurysmal disease is essential when determining the appropriateness of screening for abdominal aortic aneurysms (AAA). Although women are poorly represented in most large studies of AAA prevalence, the US Preventative Services Task Force recently recommended against primary screening for AAA in women. The purpose of this analysis was to define the prevalence and risk factors associated with the development of AAA in women. METHODS: A free duplex ultrasound screening was offered to men and women with cardiovascular risk factors or a family history of AAA. Patients were recruited through advertising at local screening centers and screenings were performed between 2004 and 2006. Demographic information and cardiovascular and aneurysmal disease risk factors were obtained for each patient through a questionnaire. A total of 17,540 subjects were screened for AAA, including 10,012 women (mean age 69.6 years) and 7528 men (mean age 70.0 years). Univariate and multivariable logistic regression analysis was performed on the subset of women that were screened to determine risk factors for and prevalence of AAA. RESULTS: Seventy-four aneurysms were detected in women (including four aneurysms >5 cm diameter and 70 aneurysms 3 to 5 cm diameter) while 291 were detected in men, resulting in prevalence rates of 0.7% and 3.9%, respectively. Increasing age (odds ratio [OR]= 4.57, 95% confidence interval [CI] 1.98 to 10.54, P < .0001), history of tobacco use (OR = 3.29, 95% CI 1.86 to 5.80, P < .0001), and cardiovascular disease (OR= 3.57, 95% CI 2.19 to 5.84, P < .0001) were independently associated with AAA in women on univariate and multivariable analysis. Women with multiple atherosclerotic risk factors were more commonly found to have AAAs and had a prevalence rate of AAA as high as 6.4%. CONCLUSION: Although the medical literature suggests a low prevalence rate of AAA in women in the general population, specific risk factors are associated with the development of AAA, and subgroups of women can be identified that are at a substantially increased risk of aneurysmal disease. In particular, elevated rates of AAA were found among women of advanced age (> or =65 years) with a history of smoking or heart disease. These data support the notion that women with such risk factors should be considered for AAA screening.     

Abdominal aortic aneurysm repair in octogenarians: outcomes and predictors.

OBJECTIVES: This study was undertaken to evaluate predictors and outcomes of octogenarians who underwent abdominal aortic aneurysm repair. DESIGN: A prospective observational study. MATERIALS AND METHODS: Between January 1st, 1997 and April 15th, 2005, 31 octogenarians were admitted to our Department with the diagnosis of abdominal aortic aneurysm. Mean follow-up time was 53.7+/-27.2 months. All patients were in good clinical condition and represented a selected healthy group of octogenarians. RESULTS: The overall perioperative (30-days) mortality rate was 3.1%. The total in-hospital morbidity rate was 22.6%. Overall survival estimates at 48 and 96 months were 81+/-8% and 46+/-21%, respectively. The actuarial freedom from aneurysm-related death at 48 and 96 months was 96+/-4% and 96+/-4%, respectively. The actuarial freedom from aneurysm-unrelated death at 48 and 96 months was 84+/-7% and 48+/-21%. Only coronary artery disease was a significant predictor of survival using multivariate stepwise logistic regression analysis. CONCLUSIONS: In this series, AAA surgery was carried out in selected octogenarians without affecting long-term survival.     

Abdominal aortic aneurysm: incidence in a population at risk

One hundred twenty patients aged fifty years and over underwent screening by ultrasound for abdominal aortic aneurysms as part of their routine follow-up visit to a cardiologist. The overall incidence of aneurysm greater than or equal to 4 centimeters in diameter was 5%. In the 84 men with aortas less than 4 centimeters, the average aorta size was 2.4 centimeters. In the 30 women with aortas less than 4 centimeters, the average aorta size was significantly smaller, 1.9 centimeters (p less than .001). It was discovered that men who smoke and have hypertension have a statistically significant increase in aorta size compared to those men without these risk factors (less than .05). The results indicate that the incidence of abdominal aortic aneurysm is probably high enough in this population to justify screening by ultrasound.