Comparison of morphologic features of intact and ruptured aneurysms of infrarenal abdominal aorta

INTRODUCTION: Endovascular aneurysm repair (EVAR) has been suggested as a technique to improve outcome of ruptured abdominal aortic aneurysm (AAA). Whether this technique becomes an established treatment will depend, in part, on the anatomy of ruptured AAA. METHODS: The anatomy of intact and ruptured AAA seen in a university department of vascular surgery over 5 years was reviewed. Aneurysm anatomy was assessed with spiral computed tomographic angiography. Suitability for EVAR was assessed from the dimensions of the proximal neck and common iliac arteries. Neck length less than 15 mm, neck width greater than 30 mm, and common iliac artery diameter greater than 22 mm were declared unsuitable for EVAR. RESULTS: Three hundred sixty-three patients with intact AAA and 46 with ruptured AAA were identified. Larger intact aneurysms were significantly associated with longer renal artery-bifurcation distance and more complex proximal neck architecture. In this sample, patients with ruptured AAA were more likely to have larger aneurysms with shorter and narrower proximal necks. Significantly more intact aneurysms were morphologically suitable for endovascular repair compared with ruptured AAA (78% vs 43%; P <.001). CONCLUSIONS: Ruptured AAA are less likely to be suitable for endovascular repair than are intact AAA, most probably because of larger diameter at presentation. Open repair will likely remain the treatment of choice in most patients with ruptured AAA, because of current morphologic constraints of endovascular repair.     

Abdominal aortic aneurysm repair in octogenarians: myth or reality?

AIM: We studied the thirty-day mortality and morbidity rate to assess the value of conventional open repair vs endovascular aortic repair (EVAR) in an elderly population presenting with a ruptured, symptomatic or asymptomatic abdominal aortic aneurysm (AAA) undergoing emergency, urgent or elective repair. METHODS: During the period from January 2004 to May 2007, 329 consecutive patients were treated for AAA in our Department. Among these, 81 (24.6%) were aged >80 years (mean age 83.6, range 80-95 years). These older patients were divided into groups according to their clinical presentation: ruptured AAA group (rAAA) - 22 cases (4 emergency EVAR, 18 emergency open repair); symptomatic non-ruptured AAA group (sAAA) - 15 cases (11 urgent EVAR, 4 urgent open repair); asymptomatic AAA group (asAAA) - 44 cases (32 elective EVAR, 12 elective open repair). The main outcome measures were 30-day mortality and 30-day morbidity rate. RESULTS: The mortality rate following open surgery vs EVAR was 66.6% vs 50% (P=NS) in the rAAA group, 25% vs 0% (P=NS) in the sAAA group, and 9% vs 3.2% (P=NS) in the asAAA group. When comparing postoperative morbidities in the octogenarians, 3 of the patients that received EVAR (6.4%) and 15 of those that received open repair (48.4%) had a severe complication (P<0.01). CONCLUSION: The introduction of EVAR has considerably changed the balance of risks and benefits for AAA treatment. Our study confirms the high mortality rate for octogenarians with rAAA and haemodynamic instability, and supports the value of an active EVAR approach for octogenarians with AAA to prevent rupture. Moreover, the introduction of endovascular techniques as part of an overall treatment algorithm for ruptured AAAs appears to be potentially associated with improved outcomes in terms of mortality and morbidity as compared to open surgical repairs alone.     

Expanding use of emergency endovascular repair for ruptured abdominal aortic aneurysms: disparities in outcomes from a nationwide perspective

BACKGROUND: Endovascular repair (EVAR) of abdominal aortic aneurysms (AAA) has become widely accepted in the elective setting but remains controversial for emergency repair of ruptured aneurysms (rAAA). We sought to examine the national trends in use and associated outcomes with EVAR. METHODS: The Nationwide Inpatient Sample (NIS) was used to analyze all admissions for rAAA from 2001 through 2004. Nationwide temporal trends and demographics using weighted samples were evaluated. Focused univariate and multivariate analyses comparing outcomes from open repair and EVAR were done for the years 2003 and 2004. RESULTS: There were 28,123 admissions for rAAA, with a stepwise decline in admissions from 2001 to 2004. Use of EVAR increased significantly from 6% of all emergency repairs in 2001 to 11% in 2004 (P < .01). Mortality for EVAR declined significantly from 43% to 29% (P < .01), but mortality with open repair showed no change (40% to 43%). From the 2003 to 2004 data set, 949 EVAR and 8982 open repairs were identified. Compared with open repair, the EVAR patients had lower mortality (31% vs 42%), shorter hospital stay (6 vs 9 days), and were more likely to be discharged to home (59% vs 37%, all P < .01). The total hospital charges for EVAR and open repair were similar (dollars 71,428 vs $74,520, P = .59). Mortality for EVAR was significantly higher at nonteaching hospitals compared with teaching centers (55% vs 21%, P < .01) and at nonteaching centers, even exceeding that of open repair (46%). Regression modeling confirmed the overall benefits of EVAR as well as the worse outcomes at nonteaching facilities after adjusting for patient comorbidities, disease severity, and hospital or system covariates. CONCLUSIONS: Endovascular repair is being increasingly used in the emergency management of ruptured AAA, with steadily decreasing mortality during the study period. Endovascular AAA repair is associated with improved mortality and outcomes compared with open repair, but results in nonteaching centers are substantially worse than those in teaching hospitals.     

Ruptured abdominal aortic aneurysm: endovascular repair is feasible in 40% of patients.

INTRODUCTION: Open repair of ruptured abdominal aortic aneurysm (rAAA) still has a high mortality. Endovascular aortic repair (EVAR) may be the way to improve survival rates. However, it is not clear how many patients with rAAA will be suitable for acute EVAR. METHODS: Between October 2000 and April 2002 all patients with acute symptomatic or ruptured AAA were assessed for EVAR on an intention-to-treat basis with emergency computed tomographic angiography (CTA). Patient and logistic characteristics were analysed. We used two commercially available aorto uni-iliac devices with a maximum proximal diameter of 28 and 34 mm. RESULTS: Five out of 26 patients were excluded for CTA and EVAR because of severe and persistent hypotension (3 pts) or logistic reasons (2 pts, both eligible). Twelve patients were found not eligible for EVAR due to unsuitable infrarenal aortic neck length (3 pts), neck diameter (1 pt) or a combination of both (8 pts). The remaining six patients were treated with EVAR. After 6 months no graft failure or aneurysm related deaths were recorded in the EVAR group. CONCLUSION: A total of 28% of patients with symptomatic or ruptured AAA was treated with EVAR. A potential 42% of patients could have been suitable for EVAR, if the correct devices had been in stock and all patients had been properly assessed.     

Anatomic suitability of ruptured abdominal aortic aneurysms for endovascular repair

Mortality from ruptured abdominal aortic aneurysms (rAAAs) remains high despite improvements in anesthesia, postoperative intensive care, and surgical techniques. Recent small series and single-center experiences suggest that endovascular aneurysm repair (EVAR) for rAAAs is feasible and may improve short-term survival. However, the applicability of EVAR to all cases of rAAA is unknown. The purpose of this study was to investigate the anatomical suitability of ruptured aneurysms for EVAR as determined by preoperative cross-sectional imaging. A contemporary consecutive series of rAAAs presenting to a tertiary academic center was retrospectively reviewed. Preoperative radiographic imaging was reviewed and assessed for endovascular compatibility based on currently available EVAR devices. Patients with aneurysm morphology demonstrating neck diameter >32 mm, neck length <10 mm, neck angulation >60 degrees, severe iliac tortuosity, or external iliac diameter <6 mm were deemed noncandidates for EVAR. Forty-seven rAAAs were treated over a 10-year period, with 47% of patients presenting with free rupture and 60% of patients transferred from outside hospitals. Five (11%) patients were treated with EVAR, all over the past 2 years, while the remaining 42 patients underwent open repair. Preoperative imaging was available for review in 43 (91%) patients, and morphological measurements indicated that 49% would have been candidates for EVAR with currently available devices. Criteria precluding EVAR in this cohort were inadequate neck length in 73%, unsuitable iliac access in 23%, large neck diameter in 18%, and severe neck angulation in 14%. Overall 30-day mortality was 34%, and 1-year mortality was 42%. Candidates for EVAR were more likely than non-EVAR candidates to be male (95% vs. 68%, p = 0.046) and to have smaller sac diameters (7.0 vs. 8.5 cm, p = 0.02) and longer neck lengths (24.1 vs. 8.6 mm, p < 0.0001); less likely to have a >60 degree angulated neck (10% vs. 45%, p = 0.0002), larger external iliac diameter (8.9 vs. 7.3 mm, p = 0.015), and less blood loss during surgical repair (2.4 vs. 6.0 L, p = 0.02); and more likely to be discharged home (71% vs. 25%, p = 0.05). There were no differences in 30-day, 1-year, or overall mortality between candidates for EVAR and noncandidates. Only 49% of patients with rAAAs in this consecutive series were found to be candidates for EVAR with conventional stent-graft devices. Differences in demographics, aneurysm morphology, and outcomes between candidates and noncandidates undergoing open repair suggest that differential risks apply to ruptured aneurysm patients. Protocols and future reports of EVAR for rAAAs should be tailored to these results. Device and technique modifications are necessary to increase the applicability of EVAR for rAAAs.     

Dynamic geometry and wall thickness of the aortic neck of abdominal aortic aneurysms with intravascular ultrasonography

BACKGROUND: It is commonly assumed that the aortic wall deforms uniformly and has uniform wall thickness about the circumference. The purpose of this study was to evaluate the aortic wall motion and thickness in the infrarenal aortic neck of patients with abdominal aortic aneurysms who were undergoing endovascular repair (EVAR) and to compare the dynamic measurements of intravascular ultrasonography with the static measurements of computed tomographic angiography (CTA). METHODS: A total of 25 patients were evaluated before surgery with CTA and three-dimensional reconstructions on a Vitrea workstation, followed by intraoperative assessment of the proximal aortic neck with intravascular ultrasonography (IVUS) before EVAR. Infrarenal aortic neck dimensions on CTA were obtained at 1-mm intervals, but for the purposes of this study all dimensions on CTA were obtained 1 cm below the lowest renal artery. IVUS analysis of the proximal aortic neck was obtained with a 10-second recorded data loop of aortic wall motion. A Digital Imaging and Communications in Medicine viewer was used to view the recorded loop of aortic movement, and each image was captured and then evaluated with a SCION PCI Frame Grabber to determine aortic dimensions and wall thickness. IVUS diameters (250 measurements of each aorta) were recorded through a full continuous cardiac cycle from the epicenter of the lumen (maintaining the left renal vein in its normal anatomic configuration) in an anteroposterior (AP) direction in the area of greatest wall movement and 90 degrees perpendicular to this direction (lateral movement). RESULTS: There was significant variation in infrarenal aortic wall movement about the circumference, with 1.7 +/- 0.6 mm (range, 0.6-2.7 mm) displacement in the AP direction and 0.9 +/- 0.5 mm (range, 0.3-1.5 mm) displacement in the lateral direction (P < .001). Aortic wall thickness was greater in the region of increased AP wall motion than in the area of lesser lateral wall motion (2.3 +/- 0.6 mm vs 1.2 +/- 0.3 mm; P < .001). There was no difference between the IVUS and CTA aortic neck measurements (25.5 vs 25.6 mm; not significant) during the midpoint of the cardiac cycle of IVUS. However, at peak systole, IVUS recorded a greater diameter than CTA (26.4 vs 25.6 mm; P < .001), and at end-diastole, IVUS recorded a smaller diameter than CTA (24.7 vs 25.6 mm; P = .01). CONCLUSIONS: The infrarenal neck of aortic aneurysms deforms anisotropically during the cardiac cycle. The greatest displacement is in the AP direction and corresponds with a significantly greater wall thickness in this area. The magnitude of cyclic change in aortic diameter can be as high as 11%. Further evaluation of proximal aortic neck wall motion after EVAR is warranted to determine the interaction of various stent designs and the aortic wall.     

Anatomic characteristics of ruptured abdominal aortic aneurysm on conventional CT scans: Implications for rupture risk

OBJECTIVE: The purpose of this study was to analyze anatomic characteristics of patients with ruptured abdominal aortic aneurysms (AAAs), with conventional two-dimensional computed tomography (CT), including comparison with control subjects matched for age, gender, and size. METHODS: Records were reviewed to identify all CT scans obtained at Dartmouth-Hitchcock Medical Center or referring hospitals before emergency AAA repair performed because of rupture or acute severe pain (RUP group). CT scans obtained before elective AAA repair (ELEC group) were reviewed for age and gender match with patients in the RUP group. More than 40 variables were measured on each CT scan. Aneurysm diameter matching was achieved by consecutively deleting the largest RUP scan and the smallest ELEC scan to prevent bias. RESULTS: CT scans were analyzed for 259 patients with AAAs: 122 RUP and 137 ELEC. Patients were well matched for age, gender, and other demographic variables or risk factors. Maximum AAA diameter was significantly different in comparisons of all patients (RUP, 6.5 +/- 2 cm vs ELEC, 5.6 +/- 1 cm; P <.0001), and mean diameter of ruptured AAAs was 5 mm smaller in female patients (6.1 +/- 2 cm vs 6.6 +/- 2 cm; P =.007). Two hundred patients were matched for diameter, gender, and age (100 from each group; maximum AAA diameter, 6.0 +/- 1 cm vs 6.0 +/- 1 cm). Analysis of diameter-matched AAAs indicated that most variables were statistically similar in the two groups, including infrarenal neck length (17 +/- 1 mm vs 19 +/- 1 mm; P =.3), maximum thrombus thickness (25 +/- 1 mm vs 23 +/- 1 mm, P =.4), and indices of body habitus, such as [(maximum AAA diameter)/(normal suprarenal aorta diameter)] or [(maximum AAA diameter)/(L3 transverse diameter)]. Multivariate analysis controlling for gender indicated that the most significant variables for rupture were aortic tortuosity (odds ratio [OR] 3.3, indicating greater risk with no or mild tortuosity), diameter asymmetry (OR, 3.2 for a 1-cm difference in major-minor axis), and current smoking (OR, 2.7, with the greater risk in current smokers). CONCLUSIONS: When matched for age, gender, and diameter, ruptured AAAs tend to be less tortuous, yet have greater cross-sectional diameter asymmetry. On conventional two-dimensional CT axial sections, it appears that when diameter asymmetry is associated with low aortic tortuosity, the larger diameter on axial sections more accurately reflects rupture risk, and when diameter asymmetry is associated with moderate or severe aortic tortuosity, the smaller diameter on axial sections more accurately reflects rupture risk. Current smoking is significantly associated with rupture, even when controlling for gender and AAA anatomy.     

Early and mid-term results of ruptured abdominal aortic aneurysms in the endovascular era in a community hospital

OBJECTIVE: Endovascular repair (EVAR) has been increasingly used for ruptured abdominal aortic aneurysms (rAAAs), especially in major academic centers. The goal of this article is to report our results with an EVAR-first approach for rAAA which we adopted in 2001 in our community hospital. METHODS: All consecutive patients who underwent attempted repair for rAAA between February 2001 and July 2006 were analyzed. Only patients with computed tomographic or visual verification of extraluminal blood were included. RESULTS: A total of 40 patients (30 men; mean age, 76.4 +/- 7.2 years; range, 57-89 years) presented with rAAA. Thirty patients underwent attempted EVAR for rAAA, constituting 4.1% of all EVAR cases (n = 738), and 10 patients had attempted open repair. Twenty-one (53%) were transferred from another institution. Computed tomography was performed in 97.5%. On arrival to the emergency department, 43%% were hypotensive (systolic blood pressure <80 mm Hg). Transfemoral balloon occlusion was used in 12 cases (30%; 10 in the EVAR group and 2 in the open group). The length of operation was 128 +/- 35 minutes (range, 77-210 minutes) in EVAR cases. EVAR was completed in 93.3% (iliac anatomy and proximal endoleak caused open conversion in two cases). Out of the 10 open treated cases, 1 was converted to EVAR and survived. The grafts used for EVAR were AneuRx (n = 21), Zenith (n = 5), and Ancure (n = 4), and 97% were bifurcated. Five patients (16.6%) in the EVAR group died within 30 days (four required balloon occlusion). The mean length of stay was 9.1 +/- 6.2 days (range, 4-30 days) in survivors of EVAR. In the EVAR-treated group, two patients died (7 and 9 months; unrelated), and six of the surviving patients (23%) required secondary procedures (five femorofemoral bypasses for limb occlusions and one proximal cuff for a type I endoleak that caused repeat rupture) during a mean follow-up of 13.8 +/- 10.4 months (range, 3-39 months). The mortality rate was 40% (4/10) in patients who underwent open procedures during this period, with an overall mortality rate of 22.5% for all ruptures treated. The difference in 30-day mortality in the EVAR and open groups did not reach statistical significance (17% vs 40%; P = .19). In the entire cohort, hypotension (systolic blood pressure <80 mm Hg) on arrival and loss of consciousness were associated with 30-day mortality. Balloon occlusion was correlated with mortality in the EVAR-treated group (44% vs 4%; P = .019). The multivariate analysis using logistic regression showed that hypotension (odds ratio [OR], 7.4; 95% confidence interval [CI], 1.3-42.0; P = .025), loss of consciousness (OR, 37.5; 95% CI, 3.4-40.8; P = .003), and the need for balloon occlusion (OR, 5.2; 95% CI, 1.8-25.5; P = .042) were correlated with higher perioperative mortality, whereas age greater than 76 years, coronary artery disease, chronic obstructive pulmonary disease, hypertension, diabetes, renal insufficiency, and type of procedure did not. CONCLUSIONS: Our results show that EVAR is feasible with favorable outcomes in patients presenting with rAAA in a busy community hospital. There is a high secondary intervention rate, which can potentially be decreased by ensuring good iliac limb anatomy at the end of the procedure and by a closer follow-up.     

Surveillance of small aortic aneurysms does not alter anatomic suitability for endovascular repair

OBJECTIVE: Small abdominal aortic aneurysms (AAAs; 4-5.4 cm) are more likely to be suitable for endovascular aneurysm repair (EVAR) than large aortic aneurysms (>5.5 cm). The purpose of this study was to determine whether small AAA growth is associated with the development of morphologic characteristics that decrease eligibility for EVAR. METHODS: We studied 54 patients who underwent 2 or more computed tomography scans with 3-dimensional reconstruction during surveillance of small AAAs. Morphologic aortic aneurysm features and changes were measured according to Society for Vascular Surgery reporting standards. Suitability for EVAR was determined by neck anatomy (diameter, length, and angulations), iliac artery morphology, and total aortic aneurysm angulation and tortuosity. RESULTS: The median age of the study cohort was 73 years (interquartile range [IQR], 65-77 years). The median follow-up period was 24 months (IQR, 15-36 months). The median small AAA diameter increased from 44.5 mm (IQR, 41-48 mm) to 48.9 mm (IQR, 45.7-52.0 mm). The median aortic neck diameter increased from 23.0 to 24.0 mm (P = .002), whereas median neck length decreased from 26.5 to 20.0 mm (P = .001). Aortic aneurysm median tortuosity index increased from 1.09 to 1.11 (P = .05). No significant changes in iliac artery morphology occurred. Overall, the anatomic suitability for endovascular repair did not significantly change during the study period (74% vs 69%; McNemar test; P = .25). CONCLUSIONS: Changes in aortic morphology are frequently associated with small AAA growth at mid-term follow-up, but such changes are minor and do not affect overall anatomic suitability for EVAR. These data reveal that continued surveillance of small AAAs does not threaten the window of opportunity for EVAR.     

Gender differences in endovascular abdominal aortic aneurysm repair with the AneuRx stent graft

OBJECTIVE: The objective of this study was to evaluate gender differences in the selection, procedure, and outcome of endovascular abdominal aortic aneurysm repair (EVAR). PATIENTS: Between October 1996 and January 2001, 378 patients were evaluated for EVAR and 189 patients underwent EVAR with the Medtronic AneuRx stent graft at a single center. RESULTS: Women constituted 17% of patients considered for EVAR. Their eligibility rate (49%) did not differ significantly from that of men (57%), and they constituted 14% of patients who underwent EVAR (26/189). Women who underwent EVAR were older (77.9 +/- 6.3 years versus 73.1 +/- 8.1 years; P <.005) with a higher rate of chronic obstructive lung disease (50% versus 28%; P <.05). Maximal aneurysm diameter (57.2 +/- 10.9 mm versus 57.8 +/- 9.4 mm; not significant) did not differ between men and women. Mean diameters of the proximal neck (20.4 +/- 2.3 mm versus 22.3 +/- 2.0 mm; P <.01), common iliac arteries (11.4 +/- 1.2 mm versus 13.5 +/- 3.6 mm; P <.001), and external iliac arteries (7.9 +/- 0.7 mm versus 9.4 +/- 1.4 mm; P <.001) were all smaller in women, and abdominal aortic aneurysm/neck diameter ratio was larger (2.82 +/- 0.59 versus 2.60 +/- 0.49; P <.05). The length of the proximal aortic neck was shorter in women (20.7 +/- 8.2 mm versus 24.5 +/- 11.8 mm; P <.05). Women had significantly more intraoperative complications (31% versus 13%; P <.05), primarily related to arterial access, and needed more frequent arterial reconstruction (42% versus 21%; P <.05), without a difference in postoperative mortality rate (0/26 versus 2/163; not significant) and complication rate (23% versus 20%: not significant). During a follow-up period of 13.8 +/- 11.7 months, no gender-related difference was found in survival rate, endoleak rate, or reintervention rate or in the rate of change in aneurysm diameter or volume. CONCLUSION: Eligibility rates of women for EVAR are similar to those of men. Women are at an increased risk for access-related complications during EVAR, but outcome is equivalent to that of men.     

To what extent has endovascular aneurysm repair influenced abdominal aortic aneurysm management in the state of Illinois?

PURPOSE: This study was performed using population-based data to determine the changing trends in the techniques for abdominal aortic aneurysm (AAA) repair in the state of Illinois during the past 9 years and to examine the extent to which endovascular aneurysm repair (EVAR) has influenced overall AAA management. METHODS: All records of patients who underwent AAA repair (1995 to 2003 inclusive) were retrieved from the Illinois Hospital Association COMPdata database. The outcome as determined by in-hospital mortality was analyzed according to intervention type (open vs EVAR) and indication (elective repair vs ruptured AAA). Data were stratified by age, gender, and hospital type (university vs community setting) and then analyzed using both univariate (chi 2 , t tests) and multivariate (stepwise logistic regression) techniques. RESULTS: Between 1995 and 2003, 14,517 patients underwent AAA repair (85% for elective and 15% for ruptured AAA). The average age was 71.4 +/- 7.9 years, and 76% were men. For elective cases, open repair was performed in 86% and EVAR in 14%; and for ruptured cases, open repair in 97% and EVAR in 3%. Elective EVAR was associated with lower in-hospital mortality compared with open repair regardless of age. No differences were observed with age after either type of repair for a ruptured aneurysm. Men had a lower in-hospital mortality compared with women for open repair of both elective and ruptured aneurysms. For EVAR, the mortality of an elective repair was lower in men, but there was no difference after a ruptured AAA. In men, the difference in mortality between elective open repair and EVAR was significant; the type of institution did not influence outcome. Patients >80 years of age had a higher mortality after open repair for both elective and ruptured AAA and after EVAR of a ruptured AAA. The average length of stay was 9.9 days for open elective repair, 13.1 days after open repair of a ruptured AAA, and 3.6 days for EVAR. The independent predictors of higher in-hospital mortality were female gender, age >80 years, diagnosis (ruptured vs open), and procedure (open vs EVAR). The year of the procedure and type of hospital (university vs community) were not predictive of outcome. CONCLUSIONS: EVAR has had a significant impact on AAA management in Illinois over a relatively short time period. In this population-based review, EVAR was associated with a significantly decreased in-hospital mortality and length of stay. Octogenarians had higher mortality after both types of repair, with the exception of elective EVAR.     

Clinical effect of abdominal aortic aneurysm endografting: 7-year concurrent comparison with open repair

OBJECTIVE: We compared the effectiveness and clinical outcome of open repair versus endovascular aortic aneurysm repair (EVAR) in achieving prevention of abdominal aortic aneurysm (AAA)-related death and graft-related complications. METHODS: Over 7 years from 1997 to 2003, 1119 consecutive patients underwent elective treatment of infrarenal AAAs, 585 with open repair and 534 with EVAR. Patients were regularly followed up at 1, 6, 12 months, and every 6 months thereafter, in EVAR group, and at 3 and 12 months, and yearly thereafter after open repair. Preoperative, intraoperative, and follow-up data were stored in a prospective database. RESULTS: Median follow-up was similar in the 2 groups: 33 months (interquartile range [IQR], 13-50 months) in the EVAR group vs 35 months (IQR, 15-54 months) in the open repair group. EVAR group patients were older than patients in the open repair group: 73 years vs 72 years (P = .04). There were statistical significant differences between the EVAR group and the open repair group with respect to AAA median diameter (52 mm vs 56 mm), coronary disease rate (46% vs 37%; P = .001), pulmonary disease rate (56% vs 38%; P < .0001), and American Society of Anesthesiologists IV score rate (16% vs 6%; P < .0001). Thirty-day mortality in the EVAR group was 0.9% (5 of 534 patients), compared with 4.1% (24 of 585 patients; P = .001) in the open repair group, and major morbidity was 9.1% (49 of 534 patients) vs 18.6% (109 of 585 patients; P < .0001), respectively. The incidence of secondary procedures in the EVAR group was 15.7%, compared with 3% in the open repair group (P < .0001). There were no deaths related to secondary procedures in either group. Six AAAs (1.1%) ruptured after EVAR, 3 of which were fatal; in the open repair group 1 patient (0.2%) underwent successful repeat operatation to treat iliac pseudoaneurysm rupture 5 years after the original procedure. Kaplan-Meier estimates for freedom from aneurysm-related death at 84 months were 97.5% in the EVAR group and 95.9% in the open repair group (log rank test, P = .008). Kaplan-Meier survival estimates at 84 months were 67.1% in the open repair group and 66.9% in the EVAR group (P = NS). At the same interval the risk for secondary procedures was 49.4% for the EVAR group and 7.1% for the open repair group. Of the 11 variables analyzed with logistic analysis, open surgery (hazard ratio [HR], 11; 95% confidence interval [CI], 2.5-54.2; P = .002), American Society of Anesthesiologists IV score (HR, 7.1; 95% CI, 2.7-18.8; P = .0001), and age (HR, 1.06; 95% CI, 1.04-1.13; P = .04) were positive independent predictors of perioperative mortality. CONCLUSION: Our data suggest that at a maximum follow-up of 7 years, patients who undergo EVAR show lower perioperative and late aneurysm-related mortality compared with a younger and substantially healthier group of patients with aneurysms treated with open repair. The higher need for secondary procedures in the endovascular group did not affect superiority of the overall performance of EVAR in the early and late intervals.     

Extended use of endovascular aneurysm sealing for ruptured abdominal aortic aneurysms

Endovascular repair of abdominal aortic aneurysms (EVAR) is now an established treatment modality for suitable patients presenting with aneurysm rupture. EVAR for ruptured aneurysms reduces transfusion, mechanical ventilation, intensive care. and hospital stay when compared with open surgery. In the emergency setting, however, EVAR is limited by low applicability due to adverse clinical or anatomical characteristics and increased need for reintervention. In addition, ongoing bleeding from aortic side branches post-EVAR can cause hemodynamic instability, larger hematomas, and abdominal compartment syndrome. Endovascular aneurysm sealing, based on polymer filling of the aneurysm, has the potential to overcome some of the limitations of EVAR for ruptured aneurysms and to improve outcomes. Recent literature suggests that endovascular aneurysm sealing can be performed with early mortality similar to that of EVAR for ruptured aortic aneurysms, but experience is limited to a few centers and a small number of patients. The addition of chimney grafts can increase the applicability of endovascular aneurysm sealing in order to treat short-neck and juxtarenal aneurysms as an alternative to fenestrated endografts. Further evaluation of the technique, with larger longitudinal studies, is necessary before advocating wider implementation of endovascular aneurysm sealing in the emergency setting.     

Elective endovascular and open repair of abdominal aortic aneurysms in octogenarians

OBJECTIVES: Endovascular aortic aneurysm repair (EVAR) is an increasingly popular treatment option for patients with abdominal aortic aneurysms (AAA), although open repair is considered the standard by virtue of its durability. Octogenarians, as a subgroup, may stand to benefit the most by EVAR. The purpose of this study is to review operative results and durability of open AAA repair and EVAR in octogenarians. METHODS: From May 1996 to August 2006, 150 patients aged >or=80 years underwent elective repair of their infrarenal AAA. Eighty-one underwent EVAR and 69 had open repair. Demographic data, aneurysm specifics, comorbidities, operative morbidity and mortality, intensive care unit and hospital length of stay, and late outcomes were analyzed. RESULTS: In the EVAR group, 27 of 81 (33%) patients died during a mean follow-up of 25 months. In the open repair group, 34 of 69 (49%) patients died during a mean follow-up of 43 months. The median survival time for EVAR was 350 weeks (range, 145-404 weeks) compared with 317 weeks (range, 233-342 weeks) for the open repair group. A Kaplan-Meier log-rank analysis showed no difference in early or long-term survival between EVAR and open repair (P = .13). EVAR was associated with decreased blood loss, decreased length of intensive care unit and hospital stays, and a greater number of patients discharged to home. CONCLUSIONS: EVAR and open repair are comparable in safety and efficacy in octogenarians. Operative repair outcomes remain acceptable. Mid- and long-term survival are similar, indicating no survival advantage of one procedure compared with the other.     

Growth rate and associated factors in small abdominal aortic aneurysms.

OBJECTIVE: To study the growth rate and factors influencing progression of small infrarenal abdominal aortic aneurysms (AAA). DESIGN: Observational, longitudinal, prospective study. PATIENTS AND METHODS: We followed patients with AAA <5 cm in diameter in two groups. Group I (AAA 3-3.9 cm, n = 246) underwent annual ultrasound scans. Group II (AAA 4-4.9 cm, n = 106) underwent 6-monthly CT scans. RESULTS: We included 352 patients (333 men and 19 women) followed for a mean of 55.2+/-37.4 months (6.3-199.8). The mean growth rate was significantly greater in group II (4.72+/-5.93 vs. 2.07+/-3.23 mm/year; p<0.0001). Group II had a greater percentage of patients with rapid aneurysm expansion (>4 mm/year) (36.8 vs. 13.8%; p<0.0001). The classical cardiovascular risk factors did not influence the AAA growth rate in group I. Chronic limb ischemia was associated with slower expansion (< or = 4 mm/year) (OR 0.47; CI 95% 0.22-0.99; p = 0.045). Diabetic patients in group II had a significantly smaller mean AAA growth rate than non-diabetics (1.69+/-3.51 vs. 5.22+/-6.11 mm/year; p = 0.032). CONCLUSIONS: The expansion rate of small AAA increases with the AAA size. AAA with a diameter of 3-3.9 cm expand slowly, and they are very unlikely to require surgical repair in 5 years. Many 4-4.9 cm AAA can be expected to reach a surgical size in the first 2 years of follow-up. Chronic limb ischemia and diabetes are associated with reduced aneurysm growth rates.     

Results of surgical therapy and classification of non-ruptured abdominal aortic aneurysms

INTRODUCTION: Surgery for symptomatic aortic abdominal aneurysms (sAAA) is associated with an increased mortality and morbidity compared to asymptomatic aortic aneurysms (aAAA). With the advent of endovascular therapy, an alternative therapeutic modality has become available. Endovascular therapy, however, depends on certain morphologic criteria, whereas open surgery can be performed on any type of AAA. The purpose of this study was to analyse our data of surgical treatment of non ruptured AAA and to identify the amount of patients in whom endovascular therapy would have been possible. METHODS: Retrospective analysis of the medical data of all patients operated upon non ruptured AAA in our department by 3 responsible vascular surgeons from 1995-1999. RESULTS: 225 consecutive patients with a median age of 65 (42-95) years were included in the study. There were 184 (82%) male and 41 (18%) female patients with 143 (63.5%) aAAA and 82 (36.5%) sAAA. Patients with sAAA underwent emergency aneurysm repair and had a significantly increased aneurysm diameter compared to the aAAA, who underwent elective surgical aneurysm repair (6.9 +/- 1.6 cm vs. 6 +/- 1.2 cm; p = 0.002). A total of 11 (4.9%) patients had an inflammatory AAA. Smoking was found to be the only significant increased preoperative risk factor in the group of sAAA compared to aAAA (91 vs. 35 patients; p = 0.008). Morbidity was significantly increased in the patients with sAAA compared to the aAAA (55% vs. 31.5%; p = 0.041) The mortality however did not differ significantly in the two groups (2 vs. 3 patients; p = 0.691). Considering morphological criteria of the AAA, endovascular therapy would have been possible in 59 (26%) patients. However, in 24 (11%) of the 59 patients, endovascular therapy was not feasible because of aortic kinking, heavy calcification of the aneurysm neck, a patent inferior mesenteric artery or atherosclerotic diseased iliac arteries. Consequently, only 35 (15%) patients would have qualified for an endovascular therapy. DISCUSSION: Surgical therapy can be performed in patients with asymptomatic and symptomatic AAA with an equal low mortality. This finding underlines the fact, that surgical therapy still remains the standard therapy for AAA. In addition, in our study only a relative small amount of patients would have qualified for an endovascular therapy.     

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.     

Aortic neck morphology after endovascular repair of descending thoracic aortic aneurysms

BACKGROUND: Endovascular repair has emerged as a less-invasive treatment for descending thoracic aortic (DTA) aneurysms. However, the durability of this procedure relies on the stability of proximal and distal fixation sites. This study analyzes 3 years of computed tomography (CT) data on aortic neck morphology after endovascular DTA aneurysm repair. METHODS: Between 1999 and 2001, 139 patients underwent successful endovascular DTA repair as part of a prospective, multicenter clinical trial investigating the Gore TAG thoracic endoprosthesis. Contrast-enhanced, high-resolution CT scans were obtained at 1 (baseline), 12, 24, and 36 months and submitted to an independent core laboratory for image analysis. The aorta was carefully measured by using computerized planimetry and a standardized protocol. Neck diameter was measured at 10-mm intervals for 2 cm above and below the aneurysm and correlated with graft migration and endoleak. RESULTS: The mean proximal neck diameter increased from a baseline of 30.2 +/- 4.6 mm to 32.0 +/- 4.3 mm at 36 months (P <.05), and the annual diameter increase was 0.8, 0.4, and 0.6 mm at 12, 24, and 36 months. The mean distal neck diameter increased from 29.4 +/- 3.8 mm to 32.1 +/- 5.0 mm at 36 months (P <.05), and the annual diameter increase was 1.1, 0.4, and 1.2 mm at 12, 24, and 36 months. At 36 months, freedom from neck dilation of > or =5 mm was 87%, and freedom from migration of > or =10 mm was 83%. An endoleak was present in 11 (9%) of 122 patients at baseline, 7 (7%) of 96 at 12 months, 6 (9%) of 68 at 24 months, and 1 (3%) of 33 at 36 months. Neck dilation was not associated with graft migration or endoleak. CONCLUSIONS: Three years after endovascular repair of DTA aneurysms, there is progressive enlargement of the proximal and distal aortic necks. Although uncommon for patients to develop significant neck dilation, when it does occur, it is not associated with graft migration or endoleak. Continued surveillance of aortic neck morphology after descending thoracic aneurysm endografting is recommended.     

An intention-to-treat by endovascular repair policy may reduce overall mortality in ruptured abdominal aortic aneurysm

OBJECTIVE: The use of endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysm (AAA) has been restricted to a small number of specialized units on a selected group of patients. The aim of this study is to assess if the overall mortality in these patients with ruptured AAA may be reduced in a unit where all patients with ruptured AAA are considered first for EVAR. METHODS: During a 24-month period beginning in July 2002, 51 patients admitted with ruptured AAA were considered for EVAR as the treatment of choice and comprised the study group. EVAR was performed in 17 patients. Open repair was performed in 34 patients: 13 patients had hemodynamic instability and 16 patients had an unsuitable aortic neck anatomy. The study group was compared with a historical control group of 41 patients with ruptured AAA who were treated by open repair from July 2000 to June 2002. RESULTS: Mortality rate was 39% in the study group compared with 59% in the control group (P = .065). The duration of stay in the intensive care unit was significantly lower in the study group than in the control group (P = .01), although the total in-hospital stay was similar (17 days vs 14 days, P = .83). Within the study group, EVAR patients had a mortality rate of 24% compared with 47% in the open group (P = .14). CONCLUSION: Although the number of patients was small, offering EVAR to as many patients as possible with ruptured AAA has resulted in a 20% reduction in mortality, albeit statistically insignificant. However, it is in the unstable patients that EVAR will need to improve survival before it may be hailed to supersede the conventional approach.     

Outcome and Quality of Life in Patients Treated for Abdominal Aortic Aneurysms: A Single Center Experience

BACKGROUND: Durability of protection and long-term quality of life (QoL) are critical outcome parameters of abdominal aortic aneurysm (AAA) repair. The aim of the present study was to compare results of endovascular and open aneurysm repair (EVAR and OR) with adjusted standard populations, including stratification for urgency of presentation. METHODS: Retrospective analysis of prospectively collected data of 401 consecutive patients presenting with AAA between January 1998 and December 2002. Cross-sectional follow up was 58 +/- 29 months. Patients were grouped into three cohorts: elective EVAR (n = 68), elective OR (n = 244), and emergency OR (including symptomatic and ruptured AAA, n = 89). Endpoints were perioperative (i.e., 30 days or in-hospital) and late mortality rates, as well as long-term QoL as assessed by the Short Form health survey questionnaire (SF-36). RESULTS: Mean age was lower in the elective OR cohort (66 +/- 10 years) than in the EVAR cohort (72 +/- 7 years; p < .05). Perioperative mortality rates were 4.4%, 0.4%, and 10.1%, for the EVAR, elective OR, and emergency OR cohorts, respectively (p < .05). Corresponding cumulative survival rates after 4 years were 67%, 89%, and 69%, respectively. Long-term QoL SF-36 scores were in all cohorts similar to age- and gender-adjusted standard populations, which score between 85 and 115: 99.6 +/- 35.8 (EVAR), 101.3 +/- 32.4 (elective OR), and 100.4 +/- 36.5 (emergency OR). CONCLUSIONS: Long-term QoL is not permanently impaired after AAA repair, but returns in long-term survivors to what would be expected in a standard population. In this respect, differences were found neither between EVAR and OR, nor between elective and emergency repair. Perioperative mortality rates were highest in patients undergoing emergency OR. The outlook for such patients after the perioperative period, however, was similar to that for patients undergoing elective repair.