Perioperative outcomes after open and endovascular repair of intact abdominal aortic aneurysms in the United States during 2001

OBJECTIVE: Small patient numbers, mixed data from clinical trials, and longitudinal series representing institutional learning curves have characterized previous studies of early outcomes after endovascular abdominal aortic aneurysm (AAA) repair. We compared the perioperative outcomes of endovascular and open surgical AAA repair in an unselected sample of patients in a single calendar year using a national administrative database. METHODS: The 2001 National Inpatient Sample database was retrospectively reviewed. This database represents 20% of all-payer stratified sample of non-federal US hospitals. Patients older than 49 years were identified by primary diagnostic codes (International Classification of Disease, ninth revision [ICD-9], 441.4, intact, nonruptured AAA) and procedure codes (ICD-9 38.44 for open, 39.71 for endovascular repair). Patient demographic data (age, sex), comorbid conditions (ICD-9 coded), inpatient complications (ICD-9 coded), length of stay, final discharge disposition (home vs institution vs death), and hospital charges were examined with univariate and multivariate analyses. RESULTS: In calendar year 2001, 7172 patients underwent either open (64%) or endovascular (36%) repair of intact, nonruptured AAAs. Despite comparable rates of preoperative comorbid conditions and a greater proportion of octogenarians (23% vs 16%%; P =.0001), morbidity (18% vs 29%; P =.0001) and mortality (1.3% vs 3.8%; P =.0001) were significantly lower for endovascular repair than for open repair. The median length of stay (2 vs 7 days; P =.0001) and the rate of discharge to an institutional facility versus home (6% vs 14%; P =.0001) were also much lower in the endovascular group than in the open repair group. At multivariate analysis, open AAA repair and age older than 80 years were strong independent predictors (P =.0001 for all) for death (open repair: odds ratio [OR], 3.3; 95% confidence interval [CI], 2.3-4.9; age: OR, 14.2; 95% CI, 3.5-58.1), complications (open repair: OR, 1.9; 95% CI, 1.7-2.1; age: OR, 1.9; 95% CI, 1.5-2.5), and not being discharged to home (open repair: OR, 3.4; 95% CI, 2.9-4.1; age: OR, 12.0; 95% CI, 7.0-20.4). Mean hospital charges were significantly greater (difference, $3337; P =.0009) for endovascular repair than for open repair. Extrapolated to the total number of endovascular AAA repairs performed during the single 2001 calendar year, this resulted in a staggering $50.3 million in additional hospital charges. CONCLUSIONS: Endovascular repair of intact AAAs results in a significantly lower number of complications and deaths, shorter hospital stay, and improved likelihood of discharge to home, even in older patients, when compared with open surgical repair. These impressive gains in clinical outcome, however, are achieved at similarly impressive increases in health care costs.     

Evaluation of the effect of endovascular options on infrarenal abdominal aortic aneurysm repair

Endovascular devices designed to exclude flow to infrarenal abdominal aortic aneurysms (AAA) were approved by the Food and Drug Administration in the United States in 1999. This action allowed widespread use of this technology for AAA exclusion. The purpose of this report is to examine trends for use of these modalities, rates of rupture of AAA, and to compare results of open AAA repair with endovascular repair. Results were collected for all hospitals, except for Veterans Administration hospitals, by a state-wide repository. Data for the years 1996 through 1998 and 2001 through 2002 were evaluated, and data from 1999 through 2000 were excluded because no separate codes were available to distinguish between open and endovascular repair. The information gathered is based on the All Patient Refined Diagnostic Related Group (APRDRG; 3M, St. Paul, MN). An average of 718 open, elective AAA was performed between 1996 and 1998. This dropped to 503 open repairs from 2001 to 2002 (P < 0.005). During that same interval, 308 endovascular elective AAA repairs were performed, therefore the total rate of elective repair increased by 100. The average rate of ruptured AAA repairs from 1996 to 1998 was 121 per year, and this dropped to 89 from 2001 to 2002 (P < 0.005). The mortality of open AAA repair during the 1996 to 1998 and 2001 to 2002 intervals was unchanged (4.7%). Mortality from endovascular AAA repair between 2001 and 2002 was 1.9 per cent (P = 0.003). Major morbidity was 14.5 per cent for open, elective AAA repair and 6.3 per cent for endovascular elective repair from 2001 to 2002 (P < 0.001). These data suggest that the advent of endovascular AAA repair has contributed to a reduction in the rate of ruptured AAA repairs, an increase in total procedures performed, and a significant decrease in perioperative deaths and major complications when compared with open AAA repair.     

Improving aneurysm-related outcomes: nationwide benefits of endovascular repair

OBJECTIVES: Endovascular aneurysm repair (EVAR) has changed the practice of abdominal aortic aneurysm (AAA) surgery. We examined a national Medicare database to establish the effect of EVAR introduction into the United States. METHODS: A 5% random sample of inpatient Medicare claims from 2000 to 2003 was queried using International Classification of Diseases, 9th Revision (ICD-9) diagnosis and procedure codes. An EVAR procedure code was available after October 2000. Occurrences were multiplied by 20 to estimate yearly national volumes and then divided into the yearly Centers for Medicare and Medicaid Services (CMS) population of elderly Medicare recipients for rates per capita, reported as cases per 100,000 elderly Medicare recipients. Statistical analysis was performed by using chi2, Student's t test, nonparametric tests, and multiple regression analysis, with significance defined as P < or = .05. RESULTS: Elective AAA repairs averaged 87.7 per 100,000 Medicare patients between 2000 and 2003, with EVAR has steadily increasing to 41% of elective repairs in 2003. From 2000 to 2003, overall elective AAA mortality declined from 5.0% to 3.7% (P < .001), while open repair mortality remained unchanged. EVAR patients are significantly older than patients treated with open repair. From 2000 to 2003 patients >84 years receiving EVAR increased to 62.7% (P < .001). Overall hospital length of stay (LOS) decreased from 8.6 days in 2000 to 7.3 days in 2003, P < .001, but increased for open AAA patients. EVAR patients were more likely to be discharged home rather than to skilled facilities. Average elective repair hospital charges were not different between groups, but Medicare reimbursement was lower for EVAR, with a higher proportion cases classified as DRG 111 (major cardiovascular procedure without complications). EVAR was used in 10.6% of ruptured AAA repairs in 2003, with a significant reduction in mortality compared with open repairs for rupture (31.8% vs 50.8%; P < .001). CONCLUSIONS: EVAR is replacing open surgery without an increase in overall case volume. EVAR is responsible for overall decrease in operative mortality even in ruptured aneurysms while decreasing utilization variables. Reimbursement to hospitals is shrinking, however.     

The impact of gender on presentation, therapy, and mortality of abdominal aortic aneurysm in the United States, 2001-2004

INTRODUCTION: The elective repair of abdominal aortic aneurysms (AAA) may decrease a patient's risk of rupture and confers a significantly lower in-hospital mortality rate than emergency repair. Previous works have shown that AAA rupture rates are higher in women compared to men, and that women have higher associated in-hospital mortality rates. This study was performed to evaluate, currently, to what extent patient gender influences presentation and treatment of AAA and the associated outcomes in the United States. METHODS: The Nationwide Inpatient Sample was used, with pertinent ICD-9 codes, to identify all patient-discharges that occurred with the primary diagnosis of intact (iAAA) or ruptured/dissecting (rAAA) abdominal aortic aneurysms between the years 2001 and 2004. Univariate and multiple logistic regression analyses of variables were performed. RESULTS: An estimated 220,403 AAA patient-discharges were identified during the study period. 37,016 (17%) patients presented with rAAA. A higher percentage of women with AAA presented with rupture compared to men (21% vs 16%; odds ratio [OR] 1.40, 95% confidence interval [CI], 1.27-1.54). This rupture rate did not significantly change from 2001 to 2004 (P = .85 for trend). For iAAA, women had higher odds of in-hospital mortality than men (OR 1.60; 95% CI, 1.24-2.07). Compared to men, in-hospital mortality rates for women with iAAA were higher for both endovascular (2.1% vs 0.83%, P < .0001) and open repairs (6.1% vs 4.0%, P < .0001). For iAAA, fewer women underwent endovascular repair (32.4% vs 46.7%, P < .0001; O.R. 0.59, 95% CI, 0.52-0.67). For patients who presented with rAAA, women were less likely to undergo surgical intervention compared to men (59% vs 70%, P < .0001). For those that underwent repair, women had higher in-hospital mortality rates than men (43% vs 36%, P < .0001; OR 1.49, 95% CI, 1.16-1.91). CONCLUSION: A higher percentage of women currently present with aneurysm rupture. They have higher in-hospital mortality rates for both iAAA and rAAA. This gender difference in the outcomes following repair of abdominal aortic aneurysm has persisted over time, the cause of which is not explained by these or previous data, a fact that warrants further investigation.     

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.     

Durability of benefits of endovascular versus conventional abdominal aortic aneurysm repair

PURPOSE: Endovascular abdominal aortic aneurysm (AAA) repair is reported to result in less initial patient morbidity and a shorter hospital length of stay (LOS) when compared with conventional AAA repair. We sought to examine the durability of this result during the intermediate follow-up interval. METHODS: The records of all admissions for all patients who underwent AAA repair during a 26-month interval were reviewed. RESULTS: Three hundred thirty-seven (337) patients underwent procedures to repair AAAs (163 open and 174 endovascular). Endovascular procedures were performed with a variety of devices (Talent, 108; Ancure, 36; AneuRx, 26; Zenith, 2; and Cordis, 2) and configurations (141 bifurcated and 33 aortomonoiliac). The mean follow-up period was 10.6 months (endovascular repair) and 12.3 months (open repair). LOS did not significantly vary by device (P =.24 to P =.92) or configuration (P =.24). The initial median LOS for procedures was significantly shorter (P =.009) for endovascular repairs (5 days) than for open procedures (8 days). However, the patients who underwent endovascular repair were more likely to be readmitted during the follow-up interval when compared with patients who underwent open procedure. The readmission-free survival rate after AAA repair at 12 months was 95% for patients for open AAA repair versus 71% for patients for endovascular repair (P <.001). If the total hospital days were compared, including the initial and all subsequent AAA-related admissions, there was no significant difference for mean LOS for patients who underwent endovascular versus open AAA procedures (11 days versus 13.6 days; P =.21). The patients for endovascular AAA repair most commonly needed readmission for treatment of endoleak (n = 31), wound infection (n = 12), and graft limb thrombosis (n = 9). Although women had similar LOS to men for endovascular repair (P =.44), they had longer initial LOS for open AAA repair (15 versus 10 days; P =.03). After endovascular repair, women were more likely than men to be readmitted by 12 months (51% versus 71% readmission-free survival rate; P =.03) and they had longer LOS on readmission (13.2 versus 5.2 days; P =.006). No gender differences were identified for patients after open AAA repair regarding readmission-free survival rate (P =.09) or LOS on readmission (P =.98). CONCLUSION: Although initial LOS was shorter for the patients who underwent endovascular as compared with conventional AAA repair, this advantage was lost during the follow-up interval because of frequent readmission for the treatment of procedure-related complications, chiefly endoleak. These readmissions frequently involved the performance of additional invasive procedures. Gender differences existed regarding LOS and the likelihood of complications after open and endovascular AAA repair.     

Endovascular repair of abdominal aortic aneurysms: eligibility rate and impact on the rate of open repair

OBJECTIVE: The purpose of this study was to determine the rate of eligibility among patients with abdominal aortic aneurysms (AAAs) considered for endovascular repair and to examine the effect of an endovascular program on the institutional pattern of AAA repair. METHODS: All patients evaluated for endovascular AAA repair since the inception of an endovascular program were reviewed for determination of eligibility rates and eventual treatment. Open AAA repairs were categorized as simple (uncomplicated infrarenal), complex (juxtarenal, suprarenal, thoracoabdominal, infected), or ruptured, and their rates before and after initiation of an endovascular program were compared. RESULTS: Over 3 years, 324 patients were considered for endovascular AAA repair; 176 (54%) were candidates, 138 (43%) were not candidates, and 10 (3%) did not complete the evaluation. The rate of eligibility increased significantly from 45% (66/148 patients) during the first half of this period to 63% (110/176 patients) during the second half (P <. 001). Candidates were significantly younger (74.4 +/- 7.6 years) than noncandidates (78.3 +/- 6.7 years) (P <.01), and their aneurysm diameter tended to be smaller (57.6 +/- 9.2 mm compared with 60.8 +/- 12.3 mm; P =.06). The most common reason for ineligibility was an inadequate proximal aortic neck. Of 176 candidates, 78% underwent endovascular repair, and 6% underwent open repair. Of 138 noncandidates, 56% underwent surgical repair. Over a period of 6 years, 542 patients with AAAs (429 simple, 86 complex, 27 ruptured) underwent open repair. The total number and ratio of simple to complex open repairs for nonruptured aneurysms during the 3 years before the initiation of the endovascular program (213 simple, 44 complex) were not significantly different from the repairs over the subsequent 3-year period (216 simple, 42 complex). Similarly, no difference in the total number and the ratio of simple to complex open repairs was found between the first and the second 18-month periods since the initiation of the endovascular program. CONCLUSIONS: The rate of eligibility of patients with AAA for endovascular repair appears to be higher than previously reported. The presence of an active endovascular program has not decreased the number or shifted the distribution of open AAA repair.     

Outcomes of endovascular treatment of ruptured abdominal aortic aneurysms

INTRODUCTION: The successful application of endovascular techniques for the elective repair of abdominal aortic aneurysms (AAAs) has stimulated a strong interest in their possible use in dealing with a long-standing surgical challenge: the ruptured abdominal aortic aneurysm (RAAA). The use of a conventional open procedure to repair ruptured aneurysms is associated with a high operative mortality of 45% to 50%. In this study, we evaluated the current frequency of endovascular repair of RAAAs in four large states and the impact of this technique on patient outcome. METHODS: We examined discharge data sets from 2000 through 2003 from the four states of California, Florida, New Jersey, and New York, whose combined population represents almost a third of the United States population. Proportions and trends were analyzed by chi2 analysis and continuous variables by the Student's t test. RESULTS: We found that since the year 2000, endovascular repair has begun to emerge as a viable treatment option for RAAAs, accounting for the repair of 6.2% of cases in 2003. During the same period, the use of open procedures for RAAAs declined. The overall mortality rate for the 4-year period was significantly lower for endovascular vs open repair (39.3% vs. 47.7%, P = .005). Moreover, compared with open repair, endovascular repair resulted in a significantly lower rate of pulmonary, renal, and bleeding complications. Survival after endovascular repair correlated with hospital experience, as assessed by the overall volume of elective and nonelective endovascular procedures. For endovascular repairs, mortality ranged from 45.9% for small volume hospitals to 26% for large volume hospitals (P = .0011). Volume was also a determinant of mortality for open repairs, albeit to a much lesser extent (51.5% for small volume hospitals, 44.3% for large volume hospitals; P < .0001). CONCLUSION: We observed a benefit to using endovascular procedures for RAAAs in institutions with significant endovascular experience; however, the analysis of administrative data cannot rule out selection bias as an explanation of better outcomes. These data strongly endorse the need for prospective studies to clarify to what extent the improved survival in RAAA patients is to be attributed to the endovascular approach rather than the selection of low-risk patients.     

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.     

A decade of change in abdominal aortic aneurysm repair in the United States: Have we improved outcomes equally between men and women?

OBJECTIVES: Abdominal aortic aneurysm (AAA) repair has undergone vast changes in the last decade. We reviewed a national database to evaluate the effect on utilization of services and rupture rates. METHODS: From the Centers for Medicare Services (CMS), a 5% inpatient sample was obtained for 1994 to 2003 as beneficiary encrypted files (5% BEF) and as a limited data set file after 2001. Files were translated into Microsoft Access by using a custom program. Queries were performed using International Classification of Diseases (9th Revision) (ICD-9) diagnosis codes 441.3 (ruptured AAA) or 441.4 (non-ruptured AAA) and ICD-9 procedure codes 38.34, 38.36, 38.44, 38.64, 39.25, 39.52 for open, and 39.71 (available after October 2000) for endovascular repair. The 5% BEF totals were multiplied by 20 to calculate yearly volumes. Total cases were divided into the yearly CMS population of elderly Medicare recipients for repair rates per capita and are reported as cases per 100,000 elderly Medicare recipients. Statistics were performed using chi2, Student's t test, nonparametric tests, and multiple regression analysis; P < or = .05 was considered significant. RESULTS: Elective AAA repairs declined from 94.4/100,000 in 1994 to 87.7/100,000 in 2003. AAA rupture surgery declined from 18.7/100,000 (1994) to 13.6/100,000 (2003). Rupture repairs from 1994 to 2003 decreased by 29% for men and by 12% for women (P < .001). Rupture mortality has not changed, but the average is significantly higher for women at 52.8%, with men averaging 44.2% (P < .001). Mortality for elective AAA repair has decreased from 5.57% (1994) to 3.20% (2003) in men (P < .001) and from 7.48% (1994) to 5.45% (2003) in women (P < .001). Multivariate analysis demonstrated increasing age, female sex, and open surgery (vs endovascular) were significant predictors of elective and ruptured AAA repair mortality. For 2003 elective AAA repairs, the average length of stay was 6.9 days in men and 8.9 days in women (P < .01) For 2003, men were more likely to be discharged to home after rupture (32.9% of men vs 23.3% of women; P < .001) and elective repair (84.5% of men vs 70.1% of women; P < .001). CONCLUSIONS: Improvements in AAA management in the last decade have decreased aneurysm-related deaths and reduced the incidence of aneurysm ruptures, with a lower utilization of services. Women, however, continue to have a consistently higher mortality for open and ruptured AAA repair and are less likely to return to home after either.     

Regionalization of abdominal aortic aneurysm repair: evidence of a shift to high-volume centers in the endovascular era

INTRODUCTION: Since the early 1990s, many studies have shown lower mortality for abdominal aortic aneurysm (AAA) repair at high-volume centers compared with low-volume centers. The introduction of endovascular AAA repair (EVAR) also has changed the practice of AAA repair. The goal of this study was to determine if regionalization of AAA repair occurred in the United States. Etiologic factors were examined in addition to any reduction in operative mortality rates. METHODS: Patient discharges of nonruptured AAA repair were identified from the Nationwide Inpatient Sample between 1998 and 2004. Hospitals were stratified by yearly AAA surgical volume of low (< or =17 cases), medium (18 to 50), and high (>50). RESULTS: A total of 46,901 patients underwent AAA repair (72.7% open vs 27.3% endovascular). The percentage of AAA repairs performed at both low-volume (36.2% to 24.3%) and medium-volume (51.0% to 44.8%) centers fell; whereas, the percentage performed at high-volume centers nearly tripled (12.9% vs 30.9%). In 1998 there were 10 high-volume centers; by 2004 this had increased to 26. The number of low-volume centers decreased, from 412 to 328. EVAR was more rapidly adopted by high-volume centers compared with low-volume centers. By 2004, 64.3% of AAA repairs at high-volume centers were done with endovascular techniques compared with 31.8% in low-volume centers. A concurrent reduction occurred in patient mortality, from 4.4% in 1998 to 2.5% in 2004 (P < .0001). CONCLUSION: Between 1998 and 2004, a trend towards the regionalization of AAA repair to high-volume centers occurred. Nearly one-third of all AAA repairs were performed at high-volume centers. There was a concurrent increase in the frequency of endovascular AAA repair, especially at high-volume centers. During this period of regionalization of AAA repair to high-volume centers, patient mortality after AAA repair decreased by 23%. Thus, the observed regionalization of AAA repair and the reduction in short-term patient mortality for this operation may be explained by increased utilization of endovascular technologies at high-volume centers.     

National audit of the recent utilization of endovascular abdominal aortic aneurysm repair in Canada: 2003 to 2004

OBJECTIVES: Worldwide, increasing proportions of aortic aneurysms are repaired electively via the endovascular route. The purpose of this study was to report the recent utilization of endovascular repair in Canada by reviewing a national administrative database. METHODS: The Canadian Institute for Health Information database (a collection of all acute care hospitalizations) was reviewed to identify patients who received nonemergent repair of an abdominal aortic aneurysm (AAA) between April 1, 2003 and March 31, 2004. During this 1-year period, differentiation between endovascular (EVAR) and open repair was possible using ICD-10-CA procedural codes in eight of ten provinces. Case volumes, patient age, length of hospitalization, and mortality were stratified by method of repair, province, and size and teaching status of hospitals. RESULTS: In this 1-year period, 1996 patients in eight provinces (representing 72% of Canada's population) underwent open repair (n = 1818, 91.1%) or EVAR (n = 178, 8.9%) of a nonruptured AAA. National utilization rates were 8.4 and 0.8 per 100,000 population for open repair and EVAR. These rates were more constant for EVAR (0 to 1.3) then for open repair (4 to 18.3) when analyzed on a provincial basis. Mean patient age did not differ between EVAR and open repair (73.7 vs 71.9 years, P = 0.4) while mean length of stay (5.8 vs 11.9 days, P = 0.03) and in-hospital mortality (0.6% vs 4.6%, P = .025) were significantly lower for EVAR than for open repair. Most EVAR (96%) and more than half of open repairs (56%) were performed in academic teaching centers. CONCLUSIONS: Although EVAR results in significant reductions in length of hospitalization and early mortality, it continues to be underutilized in Canada compared with other national reports involving administrative databases.     

Conservatism and new technology: the impact on abdominal aortic aneurysm repair

The last decade has represented a time of fundamental change in the treatment of abdominal aortic aneurysms (AAAs). Potentially, vascular surgeons will either acquire catheter-based skills or relinquish the care for many patients with infrarenal AAA. We investigated AAA referral patterns and method of AAA repair after the establishment of an endovascular AAA program at our institution. We conducted a retrospective review of elective AAA repairs after the initiation of an endovascular AAA program in April 1994. Six vascular surgeons performed all procedures with a clear distinction between the surgeons (n=3) who performed traditional AAA repair only and those (n=3) who managed AAAs by means of either endovascular or traditional treatment. From April 1994 through December 2000, 740 elective AAA repairs were performed. During this time the mean number of AAA repairs has been 106/year ranging from 75 to 155/year. More notable however is the steady increase in the percentage of endovascular AAA repairs from 6 per cent of all AAA repairs in 1994 to 61 per cent in 2000. During this time traditional surgeons have experienced a plateau in total AAA repairs performed per year with their number of open repairs decreasing by 36 per cent. At the same time endovascular surgeons have seen a progressive rise in total AAA cases including an increase of 200 per cent in open repairs and of 1367 per cent in endovascular repairs. Our vascular surgeons who repair AAA utilizing both endovascular and open techniques have experienced an increase in aneurysm referrals since the advent of an endovascular AAA program. Those who have not adopted endovascular skills have seen a decline in their aneurysm practice. The larger question about whether or not to embrace new technology before the availability of long-term follow-up remains unanswered.     

Open aneurysm repair at an endovascular center: value of a modified retroperitoneal approach in patients at high risk with difficult aneurysms

OBJECTIVE: This study was undertaken to evaluate elective open abdominal aortic aneurysm (AAA) repair and the role of a modified retroperitoneal approach in a high-volume endovascular center. METHODS: We reviewed prospectively collected data for 175 elective infrarenal open AAA repairs performed over 6 years. A transperitoneal approach was used in 118 procedures, and a modified retroperitoneal approach was used in 57 procedures. The incisional modification, which facilitated repair in patients with massive obesity, scarring, or ventral hernia, included a higher, more posterolateral location in the ninth intercostal space. Risk factors that added to the difficulty of the repair included aneurysms with a short (<1 cm) or no aortic neck in 45 patients; large, angled or flared aortic neck in 32 patients;, tortuous and calcified iliac arteries in 6 patients; morbid obesity in 10 patients; low ejection fraction (15%-30%) in 14 patients; chronic obstructive pulmonary disease, with forced expiratory volume at 1 second less than 55% in 4 patients; previous laparotomy in 18 patients; previous left-sided colectomy in 11 patients; large right iliac aneurysm in 8 patients; large ventral hernia in 8 patients; pelvic irradiation in 4 patients; failed endovascular repair in 5 patients; and previous failed open repair attempt in 2 patients. Many of these factors occurred with significantly greater frequency (P =.04-.001) in the retroperitoneal group. All factors were correlated with outcome. RESULTS: Despite these risk factors, overall 30-day mortality was 3.5% (retroperitoneal group, 3.8%), and mean length of hospital stay was 9 days (retroperitoneal group, 8 days). There was no significant correlation between mortality or length of stay and any of the mentioned risk factors (P >.2). CONCLUSION: In the era of endovascular aneurysm exclusion, open AAA repair is generally used to treat anatomically complex or difficult aneurysms, many of which are present in patients at high risk. Despite this combination of anatomic and systemic risk factors, the modified retroperitoneal approach facilitates treatment in difficult circumstances and enables open AAA repair to be performed with acceptable mortality and morbidity.     

Impact of endovascular repair on open aortic aneurysm surgical training.

PURPOSE: The purpose of this study was to determine the impact of an endovascular stent-graft program on vascular training in open aortic aneurysm surgery. METHODS: The institutional and vascular surgery fellow experience in aortic aneurysm repair during a 6-year period was reviewed. The 3-year period before introduction of endovascular repair was compared with the 3-year period after introduction of endovascular repair. All patients undergoing abdominal aortic aneurysm (AAA) or thoracoabdominal aortic aneurysm repairs were entered prospectively into a vascular registry and retrospectively analyzed to evaluate the changing patterns in aortic aneurysm treatment and surgical training. RESULTS: Between July 1994 and June 2000, a total of 588 patients with AAA or thoracoabdominal aneurysms were treated at Stanford University Medical Center. There were 296 (50%) open infrarenal AAA repairs, 87 (15%) suprarenal AAA repairs, 47 (8%) thoracoabdominal aneurysm repairs, and 153 (26%) endovascular stent-grafts. The total number of aneurysms repaired per year by vascular fellows before the endovascular program was 71.3 +/- 4.9 (range, 68-77) and increased to 124.7 +/- 35.6 (range, 91-162) after introduction of endovascular repair (P <.05). This increase was primarily caused by the addition of endovascular stent-graft repairs by vascular fellows (51.0 +/- 29.0/year [range, 23-81]). There was no change in the number of open infrarenal aortic aneurysm repairs per year, 53.0 +/- 6.6 (range, 48-56) before endovascular repair versus 47.0 +/- 1.7 (range, 46-49) after (P = not significant). There was a significant increase in the number of suprarenal AAA repairs per year by vascular fellows, 10.0 +/- 1.0 (range, 9-11) before endovascular repair compared with 19.0 +/- 6.5 (range, 13-26) after (P <.05). There was no change in the number of thoracoabdominal aneurysm repairs per year between the two groups, 8.0 +/- 3.0 (range, 4-11) before endovascular repair compared with 7.6 +/- 2.3 (range, 5-9) after. CONCLUSIONS: Introduction of an endovascular aneurysm stent-graft program significantly increased the total number of aneurysms treated. Although the number of open aneurysm repairs has remained the same, the complexity of the open aneurysm experience has increased significantly for vascular fellows in training.     

Midterm results of the multicenter trial of the powerlink bifurcated system for endovascular aortic aneurysm repair

PURPOSE: We assessed the results of abdominal aortic aneurysm (AAA) repair with the Powerlink bifurcated endovascular graft compared with open AAA repair. METHOD: A prospective controlled multicenter trial of the Powerlink system for endovascular aneurysm repair was conducted at 15 sites as part of a pivotal US Food and Drug Administration trial. Between July 2000 and March 2003, 258 patients (192 test patients, 66 control patients) were enrolled. Stent grafts were oversized by 10% to 20% relative to computed tomography scan (CT)-based diameter measurements. All repairs were performed in the operating room through 1 surgically exposed femoral artery and a contralateral 9F sheath percutaneously placed. Results were assessed with contrast material-enhanced CT scans and plain abdominal x-ray studies at 1, 6, and 12 months, and annually postoperatively. RESULTS: Patients were followed up for a mean of 22 months (median, 24 months). Technical success was achieved in 97.9% of patients, with 4 failed insertions (3 early conversions because of deployment issues, 1 access failure). There were no significant differences in mortality between the Powerlink and control groups, and only 1 death was procedure-related. Blood loss (341 mL vs 1583 mL; P < .0001), operative time (136 minutes vs 222 minutes; P < .0001), intensive care unit stay (0.78 days vs 4.1 days; P < .0001), and hospital length of stay (3.3 days vs 9.5 days; P < .0001) were significantly less in the Powerlink cohort compared with the control group. There were significantly fewer adverse events (myocardial infarction, P = .0131; renal failure, P = .0042; gastrointestinal complications, P = .0125) in the perioperative period in the Powerlink cohort compared with the control group, but in the longer follow-up interval adverse event-free survival was equivalent between groups (P = .456, log-rank test). At the time of the first-month CT scan, endoleaks were noted in 25 patients, yielding a 30-day endoleak rate of 22.7%. Type II endoleaks predominated, and there were no type III or IV endoleaks. Secondary procedures were performed in 19 patients (10%), for treatment of endoleak (n = 10), limb obstruction (n = 7), and other causes (n = 2). There were 3 graft migrations (2.2%), 1 of which resulted in an endoleak. There were no ruptures, graft fabric defects, or wire fractures. Significant reduction in mean AAA diameter and volume was noted at every follow-up interval. Increase in AAA diameter was noted in only 1.5% of patients at 24 months. CONCLUSION: The Powerlink system appears safe, and effectively protects patients from AAA rupture over the intermediate term. The graft and stent materials have thus far been free from failure and fatigue. Percutaneous contralateral limb access facilitates graft placement in patients with disadvantaged access routes. Endovascular aneurysm repair with the Powerlink system produces significantly fewer early adverse events compared with open AAA repair, but mortality is equivalent with both procedures. Careful follow-up over the longer term is necessary to ensure the durability of these results.     

A comparison of 50 initial endoluminal endograft repairs for abdominal aortic aneurysm with 50 concurrent open repairs

PURPOSE: To review the results of our initial experience with endovascular repair of abdominal aortic aneurysm (AAA) with respect to morbidity and mortality and to compare these outcomes with those of transabdominal repair. METHODS: We reviewed the first 50 consecutive endovascular AAA repairs performed at our institution from November 1999 to January 2002. Pre-operative risk factors, intraoperative variables and post-operative outcomes were assessed. All endovascular patients were followed with periodic examination, contrast-enhanced computed tomography and/or duplex scanning. Comparison was made to 50 patients undergoing standard open repair over a similar time period. RESULTS: Fifty patients underwent endovascular AAA repair (mean age 72.5, AAA size 5.5 cm). Endovascular devices employed were manufactured by Ancure (Guidant Corp.), and AneuRx (Medtronic). Preoperative risk factors were similar to patients undergoing transabdominal repair. Mean operative time was 169 minutes and estimated blood loss was 450cc with average blood replacement of.18 units. Median ICU stay was 0 days and mean hospital stay was 2.3 nights. There were no conversions to open repair, however there was one aborted endovascular attempt. Morbidity included MI (2%), colon ischemia (1%), acute renal insufficiency (4%) and leg ischemia (4%). There was one death within 30 days. Seven endoleaks were identified (6 type II and 1 type I) and were managed angiographically. CONCLUSIONS: The short-term surgical morbidity and mortality rates for endovascular repair of AAA are acceptably low and are comparable to the transabdominal approach.     

Trends in aortic aneurysm surgical training for general and vascular surgery residents in the era of endovascular abdominal aortic aneurysm repair

HYPOTHESIS: The emergence of endovascular abdominal aortic aneurysm (AAA) repair may negatively impact the open AAA experience of general surgery residents. METHODS: Prospectively collected data on general and vascular surgery resident training in AAA repair for a 5-year period (1997 to 2001) at a single institution were retrospectively reviewed. Five general surgery residents and one vascular resident completed training yearly. Institutional volume of open and endovascular repair of AAA was also assessed. RESULTS: The cumulative mean general surgical resident experience with open AAA repair fell significantly over a 5-year period; 9.5 +/- 2.5 cases were performed per general surgical resident finishing in 1997, 7.5 +/- 0.3 cases in 1998, 4.6 +/- 0.4 cases in 1999, 4.0 +/- 1.3 cases in 2000, and 4.2 +/- 1.0 cases in 2001 (P =.03). The vascular resident experience with open AAA repair did not change significantly over the 5-year period. However, the active development of an endovascular AAA program increased total AAA exposure of the vascular resident from 26 cases in 1997 to a mean of 70 cases in 2000 and 2001. The institution volume of open nonsuprarenal AAA repairs fell 38% during the 5-year period (P =.33) during a period when endovascular AAA repair increased from 9 (1996) to 55 (2000) cases (P <.001). The complexity of open AAA surgery also increased: 23.3% of open cases (7/30) in 2000 were juxta/pararenal versus 2.9% (1/35) in 1996 (P =.05). CONCLUSION: The introduction of endovascular AAA repair may have negatively impacted general surgical resident training in open AAA repair. The number of open AAA cases declined, and their complexity significantly increased. Many uncomplicated AAAs were managed with endovascular means. At programs with such a paradigm shift in AAA treatment, expectation that general surgery residents gain the proficiency necessary to safely perform AAA repair without additional training may be unrealistic.     

Experience in the United States with intact abdominal aortic aneurysm repair

OBJECTIVES: The purpose of this study was to determine the current outcome in the United States and to identify predictors of mortality and "bad outcome" after open, intact abdominal aortic aneurysm (AAA) repair. METHODS: In a retrospective analysis, data were obtained from the Nationwide Inpatient Sample during 1994-1996. The Nationwide Inpatient Sample is a 20% all-payer stratified sample of nonfederal United States hospitals. Patients older than 49 years were identified by the presence of primary diagnostic (441.4-intact AAA) and procedure (38.44-resection of abdominal aorta with replacement) codes of the International Classification of Diseases, Ninth Revision (ICD-9 ). In-hospital mortality rate, discharge disposition, bad outcome (death or discharge to an institution), complications (ICD-9 postoperative codes), length of stay, and charges were determined. The mortality rate and bad outcome were analyzed by the use of patient demographics (age, sex, race), patient comorbidities (ICD-9 diagnostic codes), calendar year, and hospital characteristics (size, location, teaching status) with univariate and multivariate analyses. RESULTS: We identified 16,450 intact AAAs repairs during the study years. The mean patient age was 72 +/- 7 (+/- SD) years, and most patients were male (79.7%) and white (94.6%). Most repairs were performed at large (67.3%), urban (92.5%), and nonteaching (66.7%) institutions. The in-hospital mortality rate was 4.2%, the overall complication rate was 32.4%, and 91.2% of patients were discharged home, whereas the bad outcome rate was 12.6%. The median length of stay was 8 days (mean, 10.0 +/- 8.1), and median hospital charges were $28,052 (mean, $35,681 +/- $33,006) in 1996 dollars. Multivariate analysis showed that the mortality rate (P <.05) increased with age (70-79 years, 1.8 odds ratio [OR] [95% CI, 1.4-2.3], > 79 years, 3.8 OR [95% CI, 2.9-4.9]), sex (female, 1.6 OR [95% CI, 1.3-1.9]), cerebral vascular occlusive disease (1.8 OR [95% CI, 1.3-2.5]), preoperative renal insufficiency (9.5 OR [95% CI, 7.7-11.7]), and more than three comorbidities (11.2 OR [95% CI, 3.6-35.4]). Multivariate analysis also showed that bad outcome was associated with the same variables in addition to hospital size (small/medium), year of procedure (1996), chronic obstructive pulmonary disease, and two to three comorbidities. CONCLUSIONS: Outcome after open repair of intact AAA across the United States is quite good. Older, sicker patients may benefit from nonoperative treatment or the potentially lower risk endovascular approaches.     

Quality of life before and after endovascular and retroperitoneal abdominal aortic aneurysm repair

PURPOSE: This study was undertaken to evaluate changes in quality of life and to compare conventional outcomes in patients undergoing endovascular and open retroperitoneal abdominal aortic aneurysm (AAA) repair. METHODS: Between October 2000 and May 2003, 129 patients underwent elective AAA repair, endovascular repair in 22 patients and open retroperitoneal repair in 107 patients. The Short-Form Health Survey, 12 items (SF-12) was administered preoperatively and at 3 weeks, 4 months, and 1 year after discharge. Quality of life, hospital and intensive care unit stay, perioperative complications, discharge disposition, readmission, and hospital cost were statistically evaluated. RESULTS: For the total group, significant differences were observed for both Physical Component Summary scores (P<.001) and Mental Component Summary scores (P=.001) between time points. There were no significant differences for either Component Summary score between open and endovascular procedures for any time period. Number of weeks required to return to baseline functional status was similar after either open or endovascular repair (7.22 vs 5.47 weeks, respectively; P=.09). Mean hospital and intensive care unit stay was 4.4 and 1 days, respectively, for open repair versus 1.9 and 0 days, respectively, for endovascular repair (P<.0001). No significant difference between groups was observed in terms of perioperative complications, discharge disposition, or hospital readmission (P> or =.54). Mean total hospital cost for endovascular repair was 1.60 times that for open repair (mean difference, $11,662; P<.0001; 95% confidence interval, $17,799-$5525). CONCLUSIONS: Hospital stay is significantly shorter after endovascular AAA repair. However, hospital cost is almost twice that for open retroperitoneal repair. Perioperative complications, discharge disposition, and hospital readmission are not statistically different between the two groups. Effect on health-related quality of life is similar after either open retroperitoneal or endovascular AAA repair.