True juxta-anastomotic aneurysms in the residual infra-renal abdominal aorta.

INTRODUCTION: abdominal aortic dilatation can occur above the graft following repair of infra-renal abdominal aortic aneurysm (AAA). This study aimed to determine the incidence and possible aetiological associations of recurrent juxta-anastomotic aneurysms following open repair of AAA. METHODS: the diameter of the infra-renal aorta above the graft of 135 patients who had previously undergone open AAA repair was determined using ultrasound. In those where the diameter was greater than 40 mm a CT scan was undertaken. Co-morbid and operative details were determined from the patients and their clinical notes. RESULTS: seven patients had true juxta-anastomotic aneurysms (>40 mm) in the residual infra-renal abdominal aorta, the occurrence of which was associated with tobacco smoking and hypertension. There was no association with other co-morbid factors, surgical operative details or the development of iliac aneurysms (which occurred in 3% of patients). CONCLUSIONS: true juxta-anastomotic aneurysms develop in the residual infra-renal neck of patients following open repair of abdominal aortic aneurysm. Tobacco smoking and hypertension are significant factors associated with the development of these aneurysms. This group of patients may warrant surveillance to prevent aneurysm rupture.     

A prospective study to assess changes in proximal aortic neck dimensions after endovascular repair of abdominal aortic aneurysms

OBJECTIVE: The purpose of this study was to detect any change in the proximal neck diameter after endovascular repair of abdominal aortic aneurysm. METHODS: The study was performed in a teaching hospital with an endovascular program on 112 patients who had undergone endovascular repair of abdominal aortic aneurysm. The interventions were pre-endovascular and postendovascular repair of abdominal aortic aneurysms with contrast-enhanced, spiral computerized tomography, and the main outcome measures were change in aortic proximal neck diameter, change in maximum aortic diameter, presence of endoleaks, and change in length from lowest renal artery to aortic bifurcation. RESULTS: The median anterior-posterior and transverse diameter decreased from 63.5 mm before surgery to 50.4 and 54.5 mm, respectively, after surgery in a period of 4 years. This trend in reduction in maximum diameter was not seen in the patients with endoleaks. There was no significant change in the proximal neck diameters when measured at 5-mm intervals after endovascular repair. There was also no significant change in the aortic length after endovascular repair. CONCLUSION: We have not demonstrated any evidence for proximal neck dilatation after endovascular repair of abdominal aortic aneurysm.     

The prevalence and natural history of aortic aneurysms in heart and abdominal organ transplant patients

OBJECTIVE: The purpose of this study was to document the prevalence and clinical features of aortic aneurysms in heart and abdominal transplant patients. METHODS: We undertook a retrospective review of 1557 patients who had heart, liver, or kidney transplantation between January 1, 1987, and December 31, 2000. Aortic aneurysms were identified by computed tomographic scan, ultrasound scan, or at the time of surgery for rupture. An aortic diameter of 3.5 cm was used as the threshold for the definition of aneurysmal disease. We compared dichotomous variables with Fisher's exact test and continuous variables with the Wilcoxon rank-sum test. RESULTS: There were 296 heart, 450 liver, and 811 kidney transplants performed on adult patients during the study period. We identified 18 transplant patients who had an aortic aneurysm (13 heart, three liver, two kidney). Seven patients (41%) had rupture of the aortic aneurysm, and five of these patients died. There were no deaths from causes other than aortic aneurysm rupture. The rate of aneurysm rupture was 22.5% per year. Eight patients had the aortic aneurysm repaired electively with no deaths and no hospital stay greater than 15 days. The mean aortic aneurysm size at rupture was 6.02 +/- 0.86 cm, and the smallest aneurysm that ruptured was 5.1 cm. The pretransplant rate of aortic aneurysm expansion was 0.46 cm/y, but this increased to 1.00 cm/y after transplantation (P =.08). The rate of aortic aneurysm expansion among heart transplant patients and abdominal transplant patients was the same (P =.51). The prevalence of aortic aneurysm was 4.1% in cardiac transplant patients and 0.4% in abdominal transplant patients. Earlier in our series (1987 to 1996), 11% of the cardiac transplant patients were screened for aortic aneurysms, and the prevalence rate of diagnosis was 3.0%. Screening of cardiac transplant candidates became more frequent in 1997 (87% screened), with an associated increase in the aortic aneurysm prevalence rate to 5.8% in the patients who were screened. CONCLUSION: Aortic aneurysms in cardiac and abdominal transplant patients have an aggressive natural history with high expansion and rupture rates. Screening transplant patients for aortic aneurysms will increase detection and facilitate elective repair, which is generally well tolerated. These findings support programs for early detection and elective treatment of aortic aneurysms in organ transplant patients, particularly those having heart transplants.     

Technical tips for endovascular repair of common iliac artery aneurysms

Isolated common iliac artery aneurysms are rare, comprising <2% of all aneurysm disease. These aneurysms present as either isolated disease, .03% of the population, or, in conjunction with abdominal aortic aneurysm, in approximately 20% to 25% of such cases. Common iliac artery aneurysms are defined as any localized dilatation of the common iliac artery >1.5 cm in diameter. Elective repair for isolated common iliac artery aneurysms is generally not undertaken for aneurysms <3 cm in diameter unless they are part of an abdominal aortic aneurysm repair. Most common iliac artery aneurysms are found incidentally during abdominal/pelvic diagnostic imaging studies or at the time of pelvic or abdominal surgery. As with abdominal aortic aneurysms, endovascular repair of common iliac artery aneurysms follows techniques similar to those used for endovascular repair of abdominal aortic aneurysm. Management includes aneurysm exclusion with an endograft, which seals at sites within the proximal and distal common iliac artery and may involve coil occlusion of the hypogastric artery with extension of the reconstruction into the proximal external iliac artery, or use a "bell-bottom" endograft limb placed at the common iliac bifurcation. Technical tips for successful outcome are described here, and all US Food and Drug Administration approved endografts have been used for repair. There were no statistically significant differences in outcomes that correlated with device or repair techniques used for management of common iliac artery aneurysms. Mid-term 54-month outcome has been excellent, with no common iliac artery ruptures or aneurysm-related deaths and the need for secondary interventions was gratifyingly small.     

Aortic necks of ruptured abdominal aneurysms dilate more than asymptomatic aneurysms after endovascular repair

BACKGROUND: Endovascular repair of abdominal aortic aneurysm (AAA) is increasingly used. We evaluated if a difference exists in the rate of change of the aortic neck diameter between non-ruptured and ruptured AAAs after endovascular aneurysm repair (EVAR). METHODS: Details of patients undergoing elective (group I) and emergency (group II) EVAR using Talent stents between October 1999 and September 2005 were reviewed. Top neck diameters were prospectively recorded on the hospital database from computed tomography scans preoperatively and at 1, 3, 12, and 24 months postoperatively. The aortic neck diameter rate of change was calculated for each group. RESULTS: Endovascular repair was performed on 110 elective and 41 emergency patients, of which 100 (80 male) elective and 29 (26 male) emergency patients were included in this analysis. Mean age was similar in each group. Stents were oversized by 20.9% +/- 13.6% in group I and by 24.7% +/- 16.3% in group II (P = .37). The preoperative mean proximal aortic neck was larger in group II (25.0 +/- 3.3 mm vs 23.5 +/- 2.8 mm; P = .029). The growth rate of the top neck diameter was significantly greater at 12 months (1.48 +/- 2.4 mm/year vs 3.89 +/- 6.24 mm/year; P = .04) and 24 months (.99 +/- 1.1 mm/year vs 2.61 +/- 3.3 mm/year; P = .04) in group II than in group I. A decreasing sac size was found in 68.2% of patients whose neck dilated. The complication rate was similar in each group. CONCLUSION: Aneurysm necks in patients with ruptured aneurysms are larger and dilate at a greater rate than those with nonruptured aneurysms. The accelerated rate of expansion in some patients must be borne in mind during follow-up and in secondary endovascular interventions and conversion to open surgery.     

Factors Affecting the Regression of Surgically Replaced Abdominal Aortic Aneurysms

Purpose After endovascular therapy for abdominal aortic aneurysms, aneurysm sac shrinkage is considered to be the best marker of successful treatment. Such shrinkage, however, is infrequent and the rate of shrinkage is variable because of endoleaks. To investigate the factors that influence such contraction, the aneurysm sac regression after a conventional surgical replacement of the abdominal aortic aneurysm in an inclusion fashion was studied. Methods Abdominal aortic aneurysms that measured 5 cm in diameter or larger were studied in 35 patients who underwent surgical replacement. The aneurysm sac was closed anterior to the prosthesis. Of the 35 cases, 4 aneurysms were inflammatory and 10 had aneurysm wall circumferential calcification of greater than 40%. Computed tomography was performed preoperatively, and at 1 week, and then 3 months postoperatively. Results The maximum major and minor diameters of the aneurysmal sac decreased significantly from 1 week to 3 months after surgery (major diameter: 49 ± 12 to 32 ± 8 mm and minor diameter: 39 ± 10 to 26 ± 7 mm). In inflammatory aneurysms, the maximum major and minor diameters were significantly larger at 3 months postoperatively, in comparison to nonspecific aneurysms. Among the 31 patients with nonspecific aneurysms, the maximum major diameter was significantly larger in those with aneurysmal calcification of greater than 40% of its circumference at 3 months postoperatively, in comparison to noncalcified aneurysms. Conclusions The surgically repaired abdominal aortic aneurysm contraction tends to develop over 3 months, and inflammation, thickening, and calcification of the aneurysm wall are all considered to influence the regression of the aneurysm.     

Probability of rupture of an abdominal aortic aneurysm after an unrelated operative procedure: a prospective study

It has been assumed by some authors that patients with abdominal aortic aneurysms may be at increased risk of rupture after unrelated operations. From July 1986 to December 1989, 33 patients (29 men, 4 women) with a known abdominal aortic aneurysm underwent 45 operations. Twenty-eight patients had an infrarenal abdominal aortic aneurysm, and five patients had a thoracoabdominal aneurysm. The abdominal aortic aneurysm ranged in transverse diameter from 3.0 to 8.5 cm (average 5.6 cm). Twenty-seven patients underwent a single operation, and six patients had two or more (range of 1 to 6). Operations performed were abdominal (13); cardiothoracic (9); head/neck (2); other vascular (11); urologic (7); amputation (2); breast (1). General anesthesia was used in 29 procedures, spinal/epidural in 6, and regional/local in 10. One postoperative death occurred from cardiopulmonary failure. One patient died of a ruptured abdominal aortic aneurysm at 20 days after coronary artery bypass (1/33 patients [3%]; 1/45 operations [2%]). Fourteen patients had repair of their abdominal aortic aneurysm at a later date, an average of 18 weeks after operation. Four patients had abdominal aortic aneurysm considered too small to warrant resection (average 3.6 cm). Four patients were considered at excessive risk for elective repair. The five thoracoabdominal aneurysm were not repaired. Four patients are awaiting repair. During this same 40-month period, two other patients, not known to have an abdominal aortic aneurysm, died of a ruptured abdominal aortic aneurysm after another operative procedure, at 21 days and 77 days. All three ruptured abdominal aortic aneurysms were 5.0 cm or greater in transverse diameter.(ABSTRACT TRUNCATED AT 250 WORDS)     

The fate of the infrarenal aortic neck after open aneurysm surgery

Purpose: The long-term success of the endovascular repair of abdominal aortic aneurysms is dependent on the secure fixation of the stent graft at the proximal and distal attachment sites. A progressive dilatation of the infrarenal neck may jeopardize this success. The data regarding this issue are scarce. However, the long-term fate of the infrarenal neck can be studied in patients who have undergone open aneurysm surgery. This was the purpose of the present investigation. Methods: Between January 1989 and December 1993, 64 patients underwent open repair of infrarenal abdominal aortic aneurysms. Of the 36 patients who were eligible for the study, 19 had preoperative computed tomography scans that were available. The 19 patients also underwent a new computed tomography scanning at a mean of 71 ± 12 months after surgery. Results: The mean preoperative aortic diameter was 25.4 ± 3.7 mm at the infrarenal neck, 24.8 ± 3.4 mm at the level of the renal arteries, and 26.7 ± 3.0 mm at the level of the superior mesenteric artery (SMA). The mean aortic diameter increased at all of the 3 levels: +2.8 ± 3.1 mm (P = .0014) at the infrarenal neck, +2.8 ± 3.0 mm (P = .0013) at the level of the renal arteries, and +1.3 ± 3.0 mm (P = .080) at the level of the SMA. The annual growth rate was 0.48 mm/y (P = .0023) at the infrarenal neck, 0.46 mm/y (P = .0010) at the level of the renal arteries, and 0.21 mm/y (P = .5811) at the level of the SMA. No correlation was found between the preoperative infrarenal neck diameter (r = .295, P = .2194), the preoperative aortic diameter at the level of the renal arteries (r = .302, P = .2088), and the preoperative aortic diameter at the level of the SMA (r = .314, P = .2043) and the corresponding growth rates. The patients were stratified into 2 groups—one with a small annual growth rate at the infrarenal neck (n = 11; ≤0.3 mm/y) and one with a larger annual growth rate (n = 8; >0.3 mm/y)—and no differences in the preoperative infrarenal neck diameter or the clinical characteristics were found between the groups. Conclusion: This investigation shows an aortic dilatation of the infrarenal neck and of the aorta at the level of the renal arteries of approximately 0.5 mm annually after open aneurysm surgery. This dilatation raises concern regarding the long-term success after endovascular repair. The data also indicate that 2 populations might exist with regard to the annual growth rate of the infrarenal neck—one with low growth rate and one with higher growth rate. This might be of interest for the future selection of patients for endovascular repair. (J Vasc Surg 1998;28:889-94.)     

EXPANSION RATES OF SMALL ABDOMINAL AORTIC ANEURYSMS

Background : The present study was carried out in order to examine those factors that influence the rate of expansion of small abdominal aortic aneurysms. Methods : A retrospective study was undertaken of 112 patients who attended the St George Vascular Laboratory between 1987 and 1997. These patients had abdominal aortic aneurysms that were considered to be too small to warrant surgical repair at the time of presentation. Sequential ultrasound examinations were used to measure maximal anteroposterior aneurysm diameter. From these data, annual growth rates were calculated. Growth rate per annum was then compared with gender, age, initial aortic aneurysm diameter, presence of hypertensive disease, cardiac disease, family history of aneurysmal disease, diabetes mellitus, smoking, beta–adrenergic blockade and lipid lowering drugs. Results : Univariate analysis showed that three factors were significantly related to growth rate: the initial size of the aortic aneurysm, the presence of cardiac disease and the presence of beta–adrenergic blockade. Conclusions : The presence of beta-adrenergic blockade appeared to have an independent effect on aneurysm growth rate, and suggests a possible role for beta-adrenergic blockade as a therapeutic strategy in controlling expansion rates of small abdominal aortic aneurysms. A controlled double-blind clinical trial is required to demonstrate this conclusively.     

Are familial abdominal aortic aneurysms different?

A 9-year prospective study of 542 consecutive patients undergoing operation by one of the authors for abdominal aortic aneurysms was undertaken to define the incidence, clinical behavior, and anatomic characteristics of familial abdominal aortic aneurysms. Eighty-two (15.1%) patients having surgery for abdominal aortic aneurysms were found to have a first-degree relative with an aneurysm, as compared to nine (1.8%) of a control group of 500 patients of similar age and sex without aneurysmal disease (p less than 0.001). Detailed analysis was next performed of the pedigree charts of patients with a positive family history of aneurysm who underwent repair of abdominal aortic aneurysms by all authors over the 9-year study period. This review identified a total study population of 86 families with 209 first-degree relatives with abdominal aortic aneurysms. Clinical and anatomic features of this familial group were compared to those of 460 patients operated on for abdominal aortic aneurysms who had no family history of abdominal aortic aneurysms. Patients with familial abdominal aortic aneurysms were more likely to be women (35% vs 14%), and men with familial abdominal aortic aneurysms tended to be about 5 years younger than the women. There was no significant difference between the patients with nonfamilial and familial abdominal aortic aneurysms in anatomic extent of aneurysmal disease, multiplicity of aneurysms, associated occlusive disease, or blood type. There was a history of aneurysm rupture in 35 of 86 (40.7%) families with familial abdominal aortic aneurysms.(ABSTRACT TRUNCATED AT 250 WORDS)     

Determination of the expansion rate and incidence of rupture of abdominal aortic aneurysms

Expansion rate and incidence of rupture of abdominal aortic aneurysms in relation to their size is a source of debate. We studied 114 patients (out of a cohort of 752 consecutive patients admitted with abdominal aortic aneurysms) who were denied any immediate operation because of patient's refusal, high surgical risk, or small transverse diameter as assessed by CT scanning and ultrasonography. All patients not operated on underwent from two to six repeated examinations during an average follow-up period of 26.8 months (range, 3 to 132). Forty-seven patients (41.2%) were subsequently operated on electively because of marked increase of transverse diameter of the aneurysm (n = 44) or for other reasons (n = 3), with a death rate of 0%. Eighteen other patients underwent emergency operation for leaking or ruptured aneurysms, and there were five deaths. The incidence of rupture was clearly related to the final diameter value, rising from 0% in aneurysms less than 40 mm to 22% in large size aneurysms (greater than or equal to 50 mm). Among the 49 patients not operated on, one died of rupture before operation and five of causes unrelated to the disease. Using individual serial measurements, we determined the linear expansion rate of the aneurysm, which proved to be related to initial diameter values: 5.3 mm/year for diameters less than 40 mm (n = 49), 6.9 mm/year in the 40 to 49 mm group (n = 41), and 7.4 mm/year for diameters of 50 mm or more (n = 24).(ABSTRACT TRUNCATED AT 250 WORDS)     

Rate of change in abdominal aortic aneurysm diameter after endovascular repair

OBJECTIVE: Untreated abdominal aortic aneurysms (AAAs) enlarge at a mean rate of 3.9 mm/y with great individual variability. We sought to determine the effect of endovascular repair on the rate of change in aneurysm size. METHODS: There were 110 patients who underwent endovascular AAA repair at Stanford University Medical Center and who were followed up for 1 to 30 months (mean, 10 months) with serial contrast-infused helical computed tomography (CT). Maximal aneurysm diameter was determined using two independent methods: (1) measured manually, from cross-sectional computed tomography (XSCT) angiograms and (2) calculated from quantitative three-dimensional computed tomography (3DCT) data as orthonormal diameter. RESULTS: Maximal cross-sectional aneurysm diameter measured by hand (XSCT) and calculated as orthonormal values (3DCT) correlated closely (r = 0.915; P <.001). The XSCT-measured diameter was larger by 2.3 +/- 3. 75 mm (P <.001), and the 95% CI for SE of the bias was 1.85 to 2.75 mm. Preoperative aneurysm diameter (XSCT 59.1 +/- 8.4 mm; 3DCT 58.1 +/- 9.3 mm) did not differ significantly from the initial postoperative diameter. Considering all patients, XSCT diameter decreased at a rate of 0.34 +/- 0.69 mm/mo, and 3DCT diameter decreased at a rate of 0.28 +/- 0.79 mm/mo. Aneurysms in patients without endoleaks had a higher rate of decrease, an XSCT diameter by 0.50 +/- 0.74 mm/mo, and 3DCT diameter by 0.46 +/- 0.84 mm/mo. In these patients, mean absolute decrease in diameter at 6 months was 3. 4 +/- 4.5 mm (XSCT) and 3.3 +/- 5.9 mm (3DCT) and at 12 months, 5.9 +/- 5.7 mm (XSCT) and 5.4 +/- 5.7 mm (3DCT). Aneurysms in patients with persistent endoleaks did not change in mean XSCT diameter, and 3DCT diameter increased by 0.12 +/- 0.52 mm/mo (not significant). Aneurysm diameter remained within 4 mm of original size in 68% (3DCT) to 71% (XSCT) of patients. In one patient, aneurysm diameter increased (XSCT and 3DCT) more than 5 mm. Four patients who had a new onset endoleak had a much higher expansion rate than those with a chronic endoleak (P <.05). CONCLUSIONS: The rate of decrease in aneurysm size (annualized 3.4-4.1 mm/y) after endovascular repair of AAA approximates the reported expansion rate in untreated aneurysms. However, individual aneurysm behavior is unpredictable, and the presence of an endoleak is unreliable in predicting changes in diameter. New onset endoleaks are associated with an enlargement rate greater than that of untreated aneurysms.     

Surgery for multiple aortic aneurysms with unstable angina pectoris; report of a case

A 77-year-old female with unstable angina pectoris was referred to our hospital for further evaluation of multiple aortic aneurysms. Computed tomography showed descending thoracic (65 mm), thoracoabdominal (40 mm) and infra-renal abdominal aneurysm (50 mm). Initially, this patient underwent off pump coronary revascularization. On 11 days after initial surgery, descending thoracic aneurysm ruptured, followed by emergent descending thoracic and thoraco-abdominal aneurysm repair. Two months later from this aortic repair, this patient successfully underwent abdominal aortic aneurysm repair. At 3 years and 7th month after the last operation, she is well without limitation of daily activities and any evidence of myocardial ischemia.     

Morphologic changes and outcome following endovascular abdominal aortic aneurysm repair as a function of aneurysm size

HYPOTHESIS: Small infrarenal abdominal aortic aneurysms have a more favorable clinical and morphologic outcome compared with medium and large abdominal aortic aneurysms following endovascular aneurysm repair(EVAR). DESIGN: A prospective clinical series of 206 patients undergoing elective EVAR between 1996 and 2001. SETTING: A tertiary care academic health center. PATIENTS: Patients were grouped according to aneurysm size: small (<50 mm), medium (50-60 mm), and large (>60 mm). INTERVENTIONS: Primary EVAR and secondary procedures to secure fixation of the stent graft and surgical conversions. MAIN OUTCOME MEASURES: Aneurysm diameter, endoleaks, and long-term morphologic changes were analyzed postoperatively with 3-dimensional reconstructions of computed tomographic angiograms. RESULTS: Groups were similar in age, comorbidities, and follow-up (mean +/- SD, 32.1 +/- 11.8 months). There were 30 small aneurysms, 92 medium aneurysms, and 84 large aneurysms, with a mean size of 45.1 +/- 3.7 mm, 53.8 +/- 3.1 mm, and 66.1 +/- 6.8 mm, respectively (P<.01). There was no significant difference in proximal neck or iliac artery diameter among the 3 groups. The proximal aortic neck length (28.1 +/- 11.6 mm [small]; 23.9 +/- 11.3 mm [medium]; and 22.1 +/- 11.6 mm [large]; P<.05) was significantly shorter in large aneurysms. Furthermore, there was a significant increase (6% [small]; 15% [medium]; and 21% [large]; P<.05) in angulated necks in large aneurysms. Following treatment, aneurysm diameter remained stable in most patients (83% [small]; 82% [medium]; and 83% [large]), with a mean decrease of 2.0 +/- 6.5 mm, 2.1 +/- 6.1 mm, and 3.7 +/- 7.7 mm in each group, respectively (P =.45). There was no difference in the incidence of endoleaks, aneurysm contraction, or aneurysm expansion based on preoperative aneurysm diameter. Secondary procedures were performed in 5 (20%) of 25, 9 (5.2%) of 170, and 5 (36%) of 11 aneurysms that contracted, remained stable, or expanded, respectively, following EVAR (P<.05). CONCLUSIONS: There is a 15% increase in neck angulation and a 27% decrease in neck length in large compared with small infrarenal abdominal aortic aneurysms, with no difference in outcome. Aneurysms that are stable following EVAR have a significantly lower incidence of requiring secondary procedures.     

Utility of computed tomography for surveillance of small abdominal aortic aneurysms. Preliminary report

To assess the ability of computed tomography to predict the potential for expansion of small abdominal aortic aneurysms, we analyzed the computed tomographic scans of 30 patients who had two or more abdominal computed tomographic scans at least 6 months apart between 1979 and 1989. Clinical variables and 10 defined objective characteristics of computed tomography were evaluated. Twenty-five men and five women with abdominal aortic aneurysms ranging from 30 to 64 mm (mean, 45 mm) were followed up with serial computed tomographic scans for a mean (+/- SE) of 26 +/- 3 months. In 19 patients, enlargement of aneurysm diameter of 3 mm or more on serial computed tomographic scans was noted, whereas in 11, there was little or no expansion. Of the clinical variables studied, only serum cholesterol correlated with an increased risk of expansion. Thrombus area, measured by computed tomography, was 7.3 +/- 0.9 cm2 in enlarging aneurysms vs 4.3 +/- 0.9 cm2 in stable aneurysms. Based on these preliminary data, we conclude that computed tomography may provide valuable information about the likelihood of future expansion of small abdominal aortic aneurysms.     

Late iliac artery aneurysms and occlusive disease after aortic tube grafts for abdominal aortic aneurysm repair. A 35-year experience.

Controversy continues over whether patients treated with straight Dacron aortic tube grafts for an abdominal aortic aneurysm remain at significant risk for subsequent development of iliac aneurysm or occlusive disease. To address this issue, the authors performed a population-based analysis of 432 patients who had an abdominal aortic aneurysm diagnosed between 1951 and 1984. Aneurysm repair was performed eventually in 206 patients (48%). To ascertain differences in late development of graft-related complications, iliac aneurysms, and arterial occlusions, the authors compared all tube-graft patients with similar numbers of bifurcated-graft patients matched for age and year of operation. In the tube-graft group, no subsequent clinically evident or autopsy-proven iliac aneurysms or iliac occlusive disease were noted. Over a mean follow-up of 6 years (range, 4 to 18 years), new aortic aneurysms occurred in the proximal aorta in both tube and bifurcated-graft patients (5.0% and 2.5%, respectively). In contrast the cumulative incidence of graft-related complications was higher with a bifurcated prosthesis (12.8%) compared with a straight graft (5.0%) (p = 0.15). These problems generally occurred 5 to 15 years postoperatively and emphasize the need for long-term graft surveillance. The authors conclude that straight tube-grafts for repair of abdominal aortic aneurysms provide excellent late patency with minimal risk of subsequent iliac aneurysm development.     

Growth rate of abdominal aortic aneurysms as measured by computed tomography

The risk of rupture of an abdominal aortic aneurysm increases with size. It has thus been recommended that small aneurysms be continuously followed with some type of imaging technique to detect when aneurysm size constitutes an indication for surgery. The present study focuses on the growth rate of abdominal aortic aneurysms in 35 patients who were subjected to repeated computerized tomographic examinations of their abdominal aortic aneurysms. Several aneurysms were measured more than twice resulting in 57 different examinations. The mean growth rate of the transverse diameter was 0.52 cm/year. The individual growth rates were, however, variable. Aneurysms with an initial transverse diameter exceeding 6 cm showed a slightly but not significantly faster increase in size compared with smaller aneurysms. No correlation between initial size and growth rate could be established. Six patients died during the study period, two from myocardial infarction, three after elective aneurysm operations and one, refused for elective operation, died after rupture. It is concluded that the growth rate measured with computed tomography agrees well with previously reported estimates obtained with ultrasonography. It is recommended that small aneurysms particularly in patients with relative contraindications to surgery be followed with repeated examinations of size.     

Variables that affect the expansion rate and outcome of small abdominal aortic aneurysms

Seventy-three patients with small (less than 6 cm in diameter) abdominal aortic aneurysms (AAAs) were selected for nonoperative management and followed up with sequential ultrasound size measurements. Fifty-four men and 19 women, 51 to 89 years of age (mean 70 years), had an initial mean AAA size of 4.1 cm (anteroposterior) x 4.3 cm (lateral) diameter, with a calculated elliptic cross-sectional area of 14.3 cm2. After a mean of 37 months of follow-up, AAA area increased at a mean rate of 20% per year (3 cm2 yr; 0.4 to 0.5 cm/yr diameter). Expansion rate was not affected by initial aneurysm size. During follow-up, only 3 patients (4%) required urgent operation (1 died), 26 patients (36%) died of non-AAA causes, and 26 patients (36%) underwent elective AAA repair because of progressive size increase (1 died). Elective operations were performed at the rate of 10% per year, when mean AAA size had increased to 22 cm2 (5.1 cm in diameter). Multiple regression analysis of clinical parameters available at presentation indicated that subsequent elective AAA repair was predicted by younger age at diagnosis and larger initial aneurysm size. As anticipated, patients who underwent surgery had more rapid aneurysm expansion (5.3 cm2/yr) compared with patients who did not undergo surgery (1.6 cm2/yr; p less than 0.05). This difference was caused by more rapid expansion during later follow-up intervals among patients selected for operation and was not predicted by the change in aneurysm size observed during initial ultrasonographic follow-up. Final aneurysm size was predicted by initial size, duration of follow-up, and both systolic and diastolic pressure.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ten-year outcome of patients with very small abdominal aortic aneurysm

BACKGROUND: The long-term fate of very small abdominal aortic aneurysms (AAA) is not well known. METHODS: Forty-one patients with asymptomatic small AAA (range 25 to 40 mm) underwent ultrasonographic surveillance. RESULTS: The median follow-up period was 7.3 years. The median linear aneurysm expansion rate was 2.0 mm/year (range 0 to 8.4). Three patients experienced aneurysm rupture (7.3%) which resulted in 1 patient'death. Thirteen patients underwent aneurysm repair (31.7%) and 1 patient died postoperatively (7.7%). The survival rate at 10-year follow-up was 59.0%. The survival rate free from aneurysm rupture and repair at 10-year follow-up was 69.9%. The median time for occurrence of aneurysm rupture was 4.9 years (range 1.8 to 10.5) and the need for aneurysm repair was 4.5 years (range 1.4 to 10.4). CONCLUSIONS: The fate of very small AAA is to slowly enlarge in size, sometimes threatening the patient's life. These observations underline the importance of continuous surveillance and the potential benefits of any medical treatment in this patient population.     

Outcome of common iliac arteries after straight aortic tube-graft placement during elective repair of infrarenal abdominal aortic aneurysms

PURPOSE: To determine the relative rates of common iliac artery (CIA) expansion after elective straight aortic tube-graft replacement of infrarenal abdominal aortic aneurysms (AAA). METHODS: Five participating centers in this 2004 study entered patients they had managed by an aortoaortic tube graft for elective AAA repair. The procedures took place between January 1995 and December 2003. Postoperative computed tomography (CT) scans were obtained for all patients in 2004 to assess changes in CIA diameter. Measurements on preoperative and postoperative CT scans were all made at the same level using the same technique. RESULTS: Entered in the study were 147 patients (138 men, 9 women) with a mean age of 68 years. Mean follow-up from aortic surgery to verification of CIA diameter on the postoperative CT scan was 4.8 years. Mean preoperative CIA diameter was 13.6 mm vs 15.2 mm postoperatively. No patient developed occlusive iliac artery disease during follow-up. Three patients (2%) required repeat surgery during follow-up for a CIA aneurysm. The 147 patients were divided into three groups based on preoperative CIA diameter shown in CT scan: group A (n = 59, 40.1%), both CIA were of normal diameter; group B (n = 53, 36.1%), ectasia (diameter between 12 and 18 mm) of at least one CIA; group C (n = 35, 23.8%), an aneurysm (diameter >18 mm) of at least one CIA. CIA diameter increased by a mean of 1 mm (9.4%) over 5.5 years in group A vs 1.7 mm (12.1%) over 4.3 years in group B and 2.3 mm (12.7%) over 4.2 years in group C. The three patients who required repeat surgery for a CIA aneurysm during follow-up were all in group C. Four variables were associated with aneurysmal change in CIA: initial CIA diameter, celiac aorta diameter on the preoperative CT scan, a coexisting aneurysm site, and the follow-up duration. CONCLUSIONS: Tube-graft placement during AAA surgery is justified even for moderate CIA dilatation (<18 mm). CIA aneurysms with a preoperative diameter > or =25 mm enlarge more rapidly and warrant insertion of a bifurcated graft during the same surgical session as AAA repair. The evolutive potential of CIA between 18 mm and 25 mm in diameter justifies a bifurcated graft when the celiac aorta diameter is >25 mm or the patient's life expectancy is > or =8 years.