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Original Contribution |

Outcomes Following Endovascular vs Open Repair of Abdominal Aortic Aneurysm:  A Randomized Trial FREE

Frank A. Lederle, MD; Julie A. Freischlag, MD; Tassos C. Kyriakides, PhD; Frank T. Padberg, MD; Jon S. Matsumura, MD; Ted R. Kohler, MD; Peter H. Lin, MD; Jessie M. Jean-Claude, MD; Dolores F. Cikrit, MD; Kathleen M. Swanson, MS, RPh; Peter N. Peduzzi, PhD; for the Open Versus Endovascular Repair (OVER) Veterans Affairs Cooperative Study Group
[+] Author Affiliations

Author Affiliations: Medicine Service, Veterans Affairs Medical Center, Minneapolis, Minnesota (Dr Lederle); Surgery Service, Veterans Affairs Medical Center, Baltimore, Maryland (Dr Freischlag); Cooperative Studies Program Coordinating Center, Veterans Affairs Medical Center, West Haven, Connecticut (Drs Kyriakides and Peduzzi); Surgery Service, Veterans Affairs Medical Center, East Orange, New Jersey (Dr Padberg); Surgery Service, Veterans Affairs Medical Center, Madison, Wisconsin (Dr Matsumura); Surgery Service, Veterans Affairs Medical Center, Seattle, Washington (Dr Kohler); Surgery Service, Veterans Affairs Medical Center, Houston, Texas (Dr Lin); Surgery Service, Veterans Affairs Medical Center, Cleveland, Ohio (Dr Jean-Claude); Surgery Service, Veterans Affairs Medical Center, Indianapolis, Indiana (Dr Cikrit); and Cooperative Studies Program Clinical Research Pharmacy Coordinating Center, Albuquerque, New Mexico (Ms Swanson).


JAMA. 2009;302(14):1535-1542. doi:10.1001/jama.2009.1426.
Text Size: A A A
Published online

Context Limited data are available to assess whether endovascular repair of abdominal aortic aneurysm (AAA) improves short-term outcomes compared with traditional open repair.

Objective To compare postoperative outcomes up to 2 years after endovascular or open repair of AAA in a planned interim report of a 9-year trial.

Design, Setting, and Patients A randomized, multicenter clinical trial of 881 veterans (aged ≥49 years) from 42 Veterans Affairs Medical Centers with eligible AAA who were candidates for both elective endovascular repair and open repair of AAA. The trial is ongoing and this report describes the period between October 15, 2002, and October 15, 2008.

Intervention Elective endovascular (n = 444) or open (n = 437) repair of AAA.

Main Outcome Measures Procedure failure, secondary therapeutic procedures, length of stay, quality of life, erectile dysfunction, major morbidity, and mortality.

Results Mean follow-up was 1.8 years. Perioperative mortality (30 days or inpatient) was lower for endovascular repair (0.5% vs 3.0%; P = .004), but there was no significant difference in mortality at 2 years (7.0% vs 9.8%, P = .13). Patients in the endovascular repair group had reduced median procedure time (2.9 vs 3.7 hours), blood loss (200 vs 1000 mL), transfusion requirement (0 vs 1.0 units), duration of mechanical ventilation (3.6 vs 5.0 hours), hospital stay (3 vs 7 days), and intensive care unit stay (1 vs 4 days), but required substantial exposure to fluoroscopy and contrast. There were no differences between the 2 groups in major morbidity, procedure failure, secondary therapeutic procedures, aneurysm-related hospitalizations, health-related quality of life, or erectile function.

Conclusions In this report of short-term outcomes after elective AAA repair, perioperative mortality was low for both procedures and lower for endovascular than open repair. The early advantage of endovascular repair was not offset by increased morbidity or mortality in the first 2 years after repair. Longer-term outcome data are needed to fully assess the relative merits of the 2 procedures.

Trial Registration clinicaltrials.gov Identifier: NCT00094575

Figures in this Article

Each year in the United States, 45 000 patients with unruptured abdominal aortic aneurysm (AAA) undergo elective repair, resulting in more than 1400 perioperative deaths.1 Endovascular repair was developed to provide a less invasive method than the standard open procedure and has been reported to reduce perioperative mortality, hospital stay, and intensive care unit (ICU) stay. However, more frequent reinterventions have also been reported and the early survival advantage was lost within 2 years in previous randomized trials conducted in Europe,24 leaving the preferred approach for AAA repair in doubt. Furthermore, the relative effects of the 2 procedures on quality of life and erectile function remain unclear.

Devices and techniques continue to improve and operative mortalities and morbidities were relatively high in the European trials, raising the question of how relevant their results are to current US practice. We report short-term perioperative outcomes after elective endovascular and open repair of AAA from a US multicenter randomized trial.

Study Oversight

The study was approved by a central human rights committee and the institutional review boards at each participating center. An independent data monitoring committee reviewed the data at regular intervals.

Patients

Eligible patients had AAA for which repair was planned and had (1) a maximum external diameter of at least 5.0 cm, (2) an associated iliac aneurysm with a maximum diameter of at least 3.0 cm, or (3) a maximum diameter of at least 4.5 cm plus either rapid enlargement (at least 0.7 cm in 6 months or 1.0 cm in 12 months) or saccular morphology. To be randomized, a patient had to have completed all preoperative evaluation, be considered a candidate for both procedures by the participating vascular surgeon, and meet the manufacturer's indications for the endovascular system that would be used if so assigned. Patients were excluded if they had previous abdominal aortic surgery, needed urgent repair, or were unable or unwilling to give informed consent or follow the protocol.

Procedures

Entry evaluation included demographics (race was recorded by study nurses using predefined categories of white, not of Hispanic origin; black, not of Hispanic origin; Hispanic; Asian/Oriental or Pacific Islander; American Indian or Alaskan Native; or other); comorbidities; medications; surgical risk using criteria developed by the RAND Corporation (eAppendix)5; measurement of height, weight, brachial, and ankle blood pressure; measurement of serum creatinine; and various parameters from preoperative aortic imaging.

Patients provided informed consent for preoperative evaluation and randomization. Randomization assigned equal probability to open or endovascular repair and was stratified by medical center using a permuted block design. Allocation was made by telephone to the coordinating center after baseline information was received and eligibility verified. Although patient assignment was of necessity unblinded, outcome data by treatment group were available during enrollment only to the biostatistician and data monitoring committee.

Open repair involves sutured anastomoses of an anatomically placed vascular graft through an abdominal or retroperitoneal incision and was performed as usual at each participating medical center. Endovascular repair involves the transluminal introduction of an expandable graft system through the femoral or iliac arteries into the aneurysmal region of the aorta and iliac arteries to exclude the aneurysm from arterial pressure. Only endovascular systems approved by the US Food and Drug Administration could be used in the study. To permit subgroup comparisons with randomized controls, the endovascular system intended for a particular patient if so assigned was reported to the coordinating center before randomization.

The protocol specified that repair should occur within 6 weeks of randomization and a study-approved vascular surgeon or interventional radiologist should perform all aneurysm repairs. Criteria for study approval were vascular surgery fellowship, certification or equivalent, or equivalent training for interventional radiologists. Individuals performing study endovascular procedures were required to have completed at least 12 procedures with adequate supervision.

Follow-up visits were scheduled 1 month after aneurysm repair, 6 and 12 months after enrollment, and then yearly. All follow-up visits after endovascular repair included computed tomography and plain radiography of the abdomen, whereas after open repair, only computed tomography at 1 year was specified, a difference intended to reflect usual clinical practice. Patients were called monthly during the first 14 months after repair and then annually midway between study visits to identify outcomes and were asked to log all health care visits. Additional follow-up information was obtained by the coordinating center using national data sets.

Outcome Measures

The primary outcome is long-term (5-9 years) all-cause mortality (October 15, 2002-October 15, 2011). Secondary outcomes included (1) procedure failure, defined as failure to complete the initial repair or any secondary therapeutic procedures resulting directly or indirectly from the initial procedure and requiring a separate trip to the procedure suite (each trip to the procedure suite counted as 1 secondary procedure, and these included any unplanned surgical procedures within 30 days of the initial procedure and any additional aorto-iliac procedures at any time); (2) short-term major morbidity, defined as myocardial infarction, stroke, amputation, or renal failure requiring dialysis within 1 year after the initial repair; (3) days in hospital and ICUs associated with the initial repair; (4) other procedure-related morbidities, such as incisional hernia, or new or worsened claudication; (5) health-related quality of life; and (6) erectile dysfunction. These secondary outcomes pertain primarily to the short-term perioperative period and are the main focus of this report.

Outcomes were adjudicated by an outcomes committee blinded (to the extent possible) to the randomized group. Aneurysm-related mortality was not a prespecified outcome because of the potential for ascertainment bias4 but is presented for comparison with other trials. All deaths within 30 days after repair or during the hospitalization for repair were considered aneurysm-related, as were all late deaths adjudicated as resulting directly or indirectly from the AAA or treatment of the AAA.

Health-related quality of life was assessed by using 2 brief questionnaires, the 36-item Short Form Health Survey (SF-36) and EQ-5D (EuroQol, Rotterdam, the Netherlands), completed at baseline and follow-up visits. The SF-36 evaluates 8 health dimensions that have been aggregated into 2 summary measures, a mental component summary and a physical component summary.6 We also computed the physical component transformed with deaths included.7 The EQ-5D8 consists of 5 questions used to generate an index score with US population-based preference weights, and a 20-cm visual analog scale. Erectile function was assessed by using the previously validated 5-item International Index of Erectile Function.9 Questionnaires were completed by the patient and reviewed for completeness by study personnel.

Statistical Analysis

We originally assumed a mortality rate of 5.6% per year following open repair1012 and 5% loss to follow-up, and planned a 4.5-year enrollment period and a minimum follow-up of 3.5 years. Three years after enrollment began in October 2002, the study was reconfigured by the investigators with the approval of the data and safety monitoring board without knowledge of results by randomized group to reflect lower than planned enrollment rate, higher mortality rate (6.6% per year), and lower losses to follow-up (1%). By increasing enrollment to 5 years and follow-up to 4 years, 872 patients would provide 80% power to detect a 25% relative reduction in mortality with 2-sided α = .05. To reach this number of patients, enrollment was continued an additional 6 months at 3 centers.

The analysis was by intention-to-treat. Estimates of cumulative event rates were calculated by the Kaplan-Meier method, and hazard ratios (HRs) with confidence intervals (CIs) were estimated by Cox proportional hazards regression models.13 The effect of treatment in prespecified subgroups was assessed by treatment-subgroup interactions in the Cox proportional hazards regression model. Variables were compared by using χ2 and t tests. P values were 2-sided and P < .05 was considered statistically significant. Statistical analyses were performed by using SAS version 9.1 (SAS Institute Inc, Cary, North Carolina).

The protocol originally specified publication of 1-year results when available on all patients to ensure that short-term postoperative outcomes would be disseminated while still maximally relevant. Because of the important changes in the effect size for survival noted during the second year of follow-up in previously published trials,24 this plan was amended by the investigators with the approval of the data and safety monitoring board without knowledge of the results in February 2007 to include all follow-up data to 2 years after randomization as of the same date of October 15, 2008.

We randomized 881 patients (aged ≥49 years) at 42 medical centers (Figure 1). The 2 groups were similar at baseline (Table 1), with no significant differences except for a greater proportion using aspirin in the open repair group. Of the 41 patients randomized with AAA of less than 5.0 cm, reasons for eligibility were iliac aneurysm in 34 patients, rapid enlargement in 4 patients, and saccular morphology in 3 patients. Fifteen patients (8 endovascular repair and 7 open repair) had abdominal or back pain noted before repair, but no aneurysm ruptures were identified at any time during the study period. More than 95% of randomized patients had the assigned repair (n = 843) and in another 2% (n = 14), the assigned repair was attempted but aborted (Figure 1).

Place holder to copy figure label and caption
Figure 1. Flow Diagram of Study Patients
Graphic Jump Location

AAA indicates abdominal aortic aneurysm.

Table Graphic Jump LocationTable 1. Patient Characteristics at the Time of Randomizationa

All 109 lead proceduralists for aneurysm repair were vascular surgeons. An endovascular system other than the one prespecified as intended was used in 43 patients in the endovascular group. Endovascular repair resulted in significantly reduced procedure time, duration of mechanical ventilation, hospital and ICU stays, blood loss, and transfusion requirement, but required substantial exposure to fluoroscopy and contrast (Table 2).

Table Graphic Jump LocationTable 2. Details of Aneurysm Repair by Randomly Assigned Groupa

Mean follow-up was 1.8 years, and 80% of patients (n = 710) had either completed 2 years of follow-up or died before 2 years (follow-up was truncated at 2 years for both study groups). Perioperative mortality was significantly higher for open repair at 30 days (0.2% vs 2.3%; P = .006), and at 30 days or during hospitalization (0.5% vs 3.0%; P = .004) (Table 3), a difference that did not appear to vary with AAA diameter (P for interaction = .25). Vital status after 2 years or by October 15, 2008, was confirmed for all but 2 patients, and national data sets contained no death reports on these 2 patients. There was no significant difference in all-cause mortality at 2 years (7.0% vs 9.8%; HR, 0.7; 95% CI, 0.4-1.1; P = .13) (Figure 2). Mortality after the perioperative period was similar in the 2 groups (6.1% vs 6.6%) (Table 3), but 4 of the late deaths in the endovascular group were aneurysm-related compared with none in the open repair group. No significant differences in mortality were observed for any of the prespecified subgroups shown in Figure 3, including patients with coronary artery disease (P = .06). No significant interactions were found between treatment effect and any subgroup characteristic.

Place holder to copy figure label and caption
Figure 2. Kaplan-Meier Curve of Cumulative Probabilities of Death From Time of Randomization
Graphic Jump Location

There was no significant difference in cumulative mortality for open vs endovascular repair (hazard ratio, 0.7; 95% confidence interval, 0.4-1.1; log-rank P  = .13).

Place holder to copy figure label and caption
Figure 3. Hazard Ratios for Death According to Baseline Characteristics
Graphic Jump Location

AAA indicates abdominal aortic aneurysm; CI, confidence interval. Size of the data markers is relative to the number of deaths in that subgroup. All P > .10 for interaction with treatment effect. For surgical risk (RAND score), see online eAppendix.5

No differences were observed between the 2 groups in procedure failures, secondary therapeutic procedures, aneurysm-related hospitalizations, or 1-year major morbidity (Table 3). The 61 secondary therapeutic procedures in the endovascular repair group included 42 endovascular procedures, 3 explantations of the graft with conversion to open repair, 9 other arterial procedures with an open component, 5 groin wound procedures, and 2 amputations (both legs of 1 patient). The 55 secondary therapeutic procedures in the open-repair group included 24 incisional hernia repairs, 7 aortic graft procedures, 4 procedures for wound complications, 4 amputations (1 toe, 1 leg, and below and above knee on same leg), 4 laparotomies for bowel obstruction, 2 laparotomies for hematoma, 2 procedures to relieve claudication, and 8 miscellaneous minor procedures.

Incisional hernia was reported in 30 patients who had open repair, resulting in secondary therapeutic procedures in 21 patients (4.9%), all of whom had undergone an anterior surgical approach in the original open repair. In the endovascular repair group, there were 134 endoleaks (blood flow between the graft and the aneurysm wall) in 110 patients (25%), resulting in 21 secondary therapeutic procedures in 18 patients (4.1%).

As shown in Table 4, there were no significant differences between the 2 groups in health-related quality of life or erectile function over the 2 years of follow-up.

Table Graphic Jump LocationTable 4. Quality of Life and Erectile Dysfunctiona

In this interim report of 2-year outcomes after elective AAA repair, endovascular repair resulted in lower perioperative mortality than open repair without evidence of excess late mortality. Hospital and ICU stays were shorter with endovascular repair and need for transfusion was decreased. No significant differences were observed in major morbidities, secondary procedures, or aneurysm-related hospitalizations.

Two European trials, the United Kingdom Endovascular Aneurysm Repair Trial 1 (EVAR-1)15 and the Dutch Randomized Endovascular Aneurysm Management (DREAM) trial,16 previously reported lower operative mortality with endovascular vs open repairs. Perioperative mortality in our study was lower than in the European trials for both treatments. Mortality within 30 days or during hospitalization for endovascular repair was 2.1% in the EVAR-1 trial, 1.2% in the DREAM trial, and 0.5% in our study, and for open repair, mortality was 6.2% in the EVAR-1 trial, 4.6% in the DREAM trial, and 3.0% in our study.15,16 We did not observe the increased mid-term mortality after endovascular repair that resulted in the loss of its early survival advantage in those trials,2,3 but all 4 late aneurysm-related deaths in our study occurred in the endovascular group.

The lower perioperative mortality in our study compared with the previous trials could result from several possible factors. First, our procedures were performed more recently, from 2002-2007 compared with 1999-2003 in the EVAR-1 and DREAM trials. Of the 15 deaths within 30 days after repair or during hospitalization in our study, 10 occurred in the first 412 patients, enrolled before April 15, 2005, including the 2 deaths in the endovascular group.

Second, our results could have been improved by enrollment of patients with small AAA. Forty-three percent of our patients (n = 382) had aneurysms smaller than 5.5 cm in diameter and therefore would not have been eligible for enrollment in the EVAR-1 trial. However, perioperative mortality rates (Table 3) and treatment effects (Figure 3) were similar between patients with AAA of less than 5.5 cm and those with larger AAA, suggesting that AAA diameter was not an important factor.

Third, there could be differences in surgical technique and postoperative care between our trial and the European trials. Procedures in our trial were performed by experienced university-affiliated vascular surgeons. Although the participation of more than 100 surgeons in our trial supports generalizability within this group, and procedures in the European trials were also performed by experienced vascular surgeons, differences between trials in surgical technique and postoperative care cannot be completely excluded. Inpatient mortality following nonruptured open AAA repair in the United States during our enrollment period was 4.5%,1 roughly half that in the United Kingdom during the EVAR-1 enrollment period,17,18 a difference that reflects the differences in operative mortalities between trials. Furthermore, previous studies have reported low perioperative mortality for AAA repair in the Veterans Affairs health system compared with other US health care organizations.19,20

Fourth, there were differences in the endovascular systems used. The EVAR-1 trial used the Medtronic Talent (which was not approved for use in the United States until after our enrollment ended) in a third of the patients and used the Gore Excluder and Medtronic AneuRx much less frequently than in our study. We did not find significant interactions between device selection and treatment effect in our study, although there was a nonsignificantly less favorable outcome after endovascular repair with AneuRx compared with other endovascular systems (Figure 3), and the 2 perioperative deaths and 2 of the 4 late aneurysm-related deaths in our endovascular group were in the AneuRx subgroup, suggesting that greater use of this device probably did not improve survival in our study relative to the European trials. In 2008, the US Food and Drug Administration issued a public health notification regarding higher than expected late aneurysm–related mortality with AneuRx.21 Longer follow-up is needed to monitor performance of the various graft systems.

Our findings of no difference in major morbidities or secondary therapeutic procedures contrast with the EVAR-1 findings of highly significant differences favoring open repair in complications and reinterventions.2 At least some of these differences between the 2 trials may result from how the categories were defined. For example, the EVAR-1 trial appears to have counted as reinterventions only procedures directly related to graft placement, whereas our study included any secondary therapeutic procedures resulting from the original procedure, such as incisional hernia repairs. Incisional hernia repairs were the most common secondary therapeutic procedures in the open-repair group in our study, occurring in 4.9% of patients at 2 years. This is comparable with the 5.8% rate reported in a Medicare population within 4 years after open repair.22 A recent meta-analysis found that open AAA repair carries a 5-fold greater risk of incisional hernia than does surgery for aortoiliac occlusive disease, possibly reflecting an underlying collagen defect in patients with AAA.23

Health-related quality of life decreased in the early postoperative period in the European trials, particularly following open repair, but these changes resolved before 6 months.4 In the DREAM trial,24 quality of life at 6 months and 1 year was lower in the endovascular group. Our study focused on later postoperative quality of life and found no differences between the 2 groups at 1 and 2 years.

Open AAA repair results in erectile dysfunction in some patients, although most of the dysfunction observed after repair in 1 large trial was not new.25 Erectile dysfunction has been reported to be reduced after endovascular repair compared with open repair, but these data are from nonrandomized retrospective surveys and are subject to recall and response bias.26,27 Our finding of no difference between open and endovascular repair in erectile dysfunction at 1 and 2 years is in agreement with randomized prospective data from the DREAM trial, which reported no difference between open and endovascular repair in erectile dysfunction at 3, 6, and 12 months.28

In this randomized trial, endovascular repair resulted in fewer perioperative deaths than open repair, even though open repair was performed with low mortality. This early advantage was not offset by increased morbidity or mortality in the endovascular group in the first 2 years after repair. Longer-term data are needed to fully assess the relative merits of the 2 procedures.

Corresponding Author: Frank A. Lederle, MD, Department of Medicine (III-0), Veterans Affairs Medical Center, 1 Veterans Dr, Minneapolis, MN 55417 (frank.lederle@va.gov).

Author Contributions: Drs Lederle and Kyriakides had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Lederle, Freischlag, Kyriakides, Padberg, Kohler, Lin, Peduzzi.

Acquisition of data: Freischlag, Kyriakides, Padberg, Matsumura, Kohler, Lin, Jean-Claude, Cikrit, Swanson.

Analysis and interpretation of data: Lederle, Freischlag, Kyriakides, Padberg, Matsumura, Kohler, Jean-Claude, Swanson.

Drafting of the manuscript: Lederle, Kyriakides, Padberg, Matsumura, Kohler, Jean-Claude, Swanson, Peduzzi.

Critical revision of the manuscript for important intellectual content: Lederle, Freischlag, Kyriakides, Padberg, Matsumura, Kohler, Lin, Jean-Claude, Cikrit, Peduzzi.

Statistical analysis: Kyriakides.

Obtained funding: Lederle, Freischlag, Peduzzi.

Administrative, technical, or material support: Lederle, Freischlag, Padberg, Matsumura, Kohler, Lin, Swanson, Peduzzi.

Study supervision: Lederle, Freischlag, Padberg, Lin, Cikrit.

Financial Disclosures: Dr Matsumura reported receiving research support, consultant fees, or training director fees from Abbott/Guidant, Abraxis, Bard, Cook, Cordis, ev3, Lumen, Medtronic, Sanofi, and WL Gore. Dr Kohler reported receiving research support as an investigator for the Medtronic AneuRx Phase III clinical trial. All other authors reported no financial disclosures.

Investigators and Site Coordinators of the Open Versus Endovascular Repair (OVER) Veterans Affairs Cooperative Study Group:Participating Veterans Affairs Medical Centers: Albuquerque, New Mexico: E. R. Ketteler, MD, D. D. Kingsley, MD, J. M. Marek, MD, R. J. Massen, MD, B. D. Matteson, MD, J. D. Pitcher, MD, M. Langsfeld, MD, J. D. Corson, MD, J. M. Goff Jr, MD, K. Kasirajan, MD, C. Paap, RN, D. C. Robertson, RN; Atlanta, Georgia: R. Veeraswamy, MD, R. Milner, MD, A. Salam, MD, K. Kasirajan, MD, J. Guidot, RN; Baltimore, Maryland: S. Busuttil, MD, M. P. Lilly, MD, M. Braganza, K. Ellis, RN; Birmingham, Alabama: M. A. Patterson, MD, W. D. Jordon, MD, D. Whitley, MD, S. Taylor, MD, M. Passman, MD, D. Kerns, RN, C. Inman, RN, J. Poirier, RN; Boston, Massachusetts: J. Ebaugh, MD, J. Raffetto, MD, D. Chew, MD, S. Lathi, MD, C. Owens, MD, K. Hickson, RN; Buffalo, New York: H. H. Dosluoglu, MD, K. Eschberger, RN; Chicago, Illinois: M. R. Kibbe, MD, H. M. Baraniewski, MD, J. Matsumura, MD, A. Busman, RN, W. Meadows, RN, M. Evans, RN; Cincinnati, Ohio: H. El Sayed, MD, A. B. Reed, MD, J. S. Giglia, MD, S. Ross, RN, M. Ruf, RN; Cleveland, Ohio: J. M. Jean-Claude, MD, G. Pinault, MD, P. Kang, MD, N. White, RN, M. Eiseman, RN, R. Jones, RN†; Dallas, Texas: J. G. Modrall, MD, C. H. Timaran, MD, M. B. Welborn III, MD, J. Lopez, MD, T. Nguyen; Detroit, Michigan: J. K.Y. Chacko, MD, K. Granke, MD, A. G. Vouyouka, MD, E. Olgren, P. Chand, MD, B. Allende; M. Ranella, C. Yales, RN; Denver, Colorado: T. A. Whitehill, MD, W. C. Krupski, MD†, M. R. Nehler, MD, S. P. Johnson, MD, D. N. Jones, PhD, P. Strecker, RN, M. A. Bhola, RN; Durham, North Carolina: C. K. Shortell, MD, J. L. Gray, MD, J. H. Lawson, MD, M. W. Sebastian, MD, J. Kistler Tetterton, NP, C. Blackwell, RN, P. A. Prinzo, BS, N. Lee, RN; East Orange, New Jersey: F. T. Padberg Jr, MD, J. J. Cerveira, MD, B. K. Lal, MD, R. W. Zickler, MD, K. A. Hauck, RN; Gainesville, Florida: S. A. Berceli, MD, W. A. Lee, MD, C. K. Ozaki, MD, P. R. Nelson, MD, A. S. Irwin, RN, R. Baum, RN; Hines, Illinois: B. Aulivola, MD, H. Rodriguez, MD, F. N. Littooy, MD, H. Greislev, MD, M. T. O’Sullivan, RN; Houston, Texas: P. H. Lin, MD, R. L. Bush, MD, P. Kougias, MD, G. Guinn, MD, C. Cagiannos, MD, S. Pillack, RN, B. Guillory, RN; Indianapolis, Indiana: D. Cikrit, MD, S. G. Lalka, MD, R. Nachreiner, MD, M. Rusomaroff, RN, E. O’Brien, RN; Iowa City, Iowa: J. Hoballah, MD, W. J. Sharp, MD, J. L. McCandless, RN, V. Beach; Lexington, Kentucky: D. Minion, MD, T. H. Schwarcz, MD, J. Kimbrough, RN, L. Ashe, A. Rockich, MS, J. Warner-Carpenter, RN; Little Rock, Arkansas: M. Moursi, MD, J. F. Eidt, MD, S. Brock RN; Loma Linda, California: C. Bianchi, MD, V. Bishop, RN; Long Beach, California: I. L. Gordon, MD, R. Fujitani, MD, S. M. Kubaska III, MD, R. Azadegan, C. Ma Agas, MPH, K. Zalecki; Madison, Wisconsin: J. R. Hoch, MD, S. C. Carr, MD, C. Acher, MD, M. Schwarze, MD, G. Tefera, MD, M. Mell, MD, J. Rieder, RN; Memphis, Tennessee: J. M. Stuart, MD, D. S. Weiman, MD, O. Abul-Khoudoud, MD, H. E. Garrett, MD, S. M. Walsh, MA, K. L. Wilson, RN; Milwaukee, Wisconsin: G. R. Seabrook, MD, R. A. Cambria, MD, K. R. Brown, MD, B. Lewis, MD, S. Framberg, RN, C. Kallio, RN; Minneapolis, Minnesota: R. A. Barke, MD, S. M. Santilli, MD, A. C. d’Audiffret, MD, N. Oberle, RN, C. Proebstle, NP, L. L. Johnson, RN; New York, New York: G. R. Jacobowitz, MD, N. Cayne, MD, C. Rockman, MD, M. Adelman, MD, P. Gagne, MD, M. Nalbandian, MD, L. J. Caropolo, BS; Omaha, Nebraska: I. I. Pipinos, MD, J. Johanning, MD, T. Lynch, MD, H. DeSpiegelaere, RN, G. Purviance, RN; Palo Alto, California: W. Zhou, MD, R. Dalman, MD, J. T. Lee, MD, B. Safadi, MD, S. M. Coogan, MD, S. M. Wren, MD, D. Bahmani, D. Maples, NP, S. Thunen, RN; Philadelphia, Pennsylvania: M. A. Golden, MD, M. E. Mitchell, MD, R. Fairman, MD, S. Reinhardt, RN; Pittsburgh, Pennsylvania: M. A. Wilson, MD, E. Tzeng, MD, S. Muluk, MD, N. M. Peterson, RN, M. Foster, RN; Portland, Oregon: J. Edwards, MD, G. L. Moneta, MD, G. Landry, MD, L. Taylor, MD, R. Yeager, MD, E. Cannady, RN; Salt Lake City, Idaho: G. Treiman, MD, S. Hatton-Ward, RN, B. Salabsky, RN†; San Francisco, California: J. H. Rapp, MD, L. M. Reilly, MD, R. Sarkar, MD, S. S. Dwyer, RN; Seattle, Washington: T. R. Kohler, MD, T. S. Hatsukami, MD, D. G. Glickerman, MD, M. Sobel, MD, T. S. Burdick, MD, K. Pedersen, RN, P. Cleary, NP; San Diego, California: N. Kansal, MD, N. H. Kumins, MD, M. Estes, RN, B. A. Forbes, RN, C. Sobotta, RN; Tampa, Florida: M. Back, MD, D. Bandyk, MD, B. Johnson, MD, M. Shames, MD, R. L. Reinhard, RN, S. C. Thomas, RN; Tucson, Arizona: L. R. Leon Jr, MD, A. Westerband, MD, R. J. Guerra, MD, M. Riveros, MD, J. L. Mills, SR, MD, J. D. Hughes, MD, S. .B. Psalms, N. N. Day, RN; Washington, DC: A. Sidawy, MD, J. M. Weiswasser, MD, S. Arora, MD, B. J. Jasper, M Ed; West Haven, Connecticut: A. Dardik, MD, V. Gahtan, MD, B. E. Muhs, MD, B. E. Sumpio, MD, R. J. Gusberg, MD, M. Spector, MD, J. Pollak, MD, J. Aruny, MD, E. L. Kelly, MD, J. Wong, MD, P. Vasilas, RN, C. Joncas, RN; West Los Angeles, California: H. A. Gelabert, MD, C. DeVirgillio, MD, D. A. Rigberg, MD, L. Cole, RN.

Executive Committee: Frank A. Lederle, MD, and Julie A. Freischlag, MD (co-chairpersons), Ted R. Kohler, MD, Jon Matsumura, MD, Frank T. Padberg Jr, MD, Tassos C. Kyriakides, PhD, Kathleen M. Swanson, MS, RPh, Julie Thornton, Yvonne Jonk, PhD, Kevin T. Stroupe, PhD.

Coordinating Centers and Committees:Cooperative Studies Program Coordinating Center (CSPCC) VA CT Healthcare System,West Haven, Connecticut: Peter Peduzzi, PhD (director), Margaret Antonelli (assistant director, operations), Cindy Cushing (programmer), Lynn Durant (quality assurance officer), Shirley Joyner, MHA (research coordinator), Tassos C. Kyriakides, PhD (biostatistician), Mary LeGwin (project manager), Terry O’Connor, PhD (biostatistician), Scott Zellner, PhD (research coordinator), Vanessa McBride (research coordinator), Susan Stratton† (project manager), Elizabeth Davis, RN, Alice Kossack, June Poulton, RN (research associate); Regulatory Affairs and Clinical Compliance Section, Cooperative Studies Program Clinical Research Pharmacy Coordinating Center, Albuquerque, New Mexico: Kathleen M. Swanson, MS, RPH, Julie Thornton, BS; VA Research Site Management and Review Team (SMART)VA Cooperative Studies Program,Albuquerque, New Mexico: Clair M. Haakenson, RPH, MS; Health Economists: Kevin T. Stroupe, PhD (Center for Management of Complex Chronic Care, CSPCC, Veterans Affairs Medical Center, Hines, Illinois), Yvonne Jonk, PhD (Center for Chronic Disease Outcomes Research, Veterans Affairs Medical Center, Minneapolis, Minnesota); Human Rights Committee, West Haven, Connecticut: Richard Marottoli, MD, Stanislav Kasl, PhD, Rajni Mehta, MPH, Richard Feldman, William Farrell, Heather Allore, PhD, Edward Perry, MD, James Niederman, MD, Sister Frances Randall, Reverend Michael Zeman, Donald Beckwith; National Project Coordinators, Minneapolis VAMC: Elizabeth Latts, MSW, Marilyn Bader; Central Administration, Cooperative Studies Program (VA Central Office): Timothy J. O’Leary, MD, PhD, director, Clinical Science R&D Service, Grant D. Huang, PhD, deputy director, CSP. †Deceased.

Data and Safety Monitoring Board: John (Jeb) W. Hallett, MD (Roper-St. Francis Heart and Vascular Center, Charleston, South Carolina), Norman Hertzer, MD (The Cleveland Clinic, Cleveland, Ohio), Jonathan Towne, MD (Medical College of Wisconsin, Milwaukee), David A. Katz, MD, MSc (Center for Research in the Implementation of Innovative Strategies in Practice, US Department of Veterans Affairs, Iowa City Health Care System, Iowa City, Iowa), Theodore Karrison, PhD (biostatistician) (Department of Health Studies, University of Chicago, Chicago, Illinois), John P. Matts, PhD (biostatistician) (Coordinating Centers for Biometric Research, University of Minnesota, Minneapolis).

Funding/Support: This work was supported by the Cooperative Studies Program of the Department of Veterans Affairs (VA) Office of Research and Development, Washington, DC. Study nurses were compensated directly by the VA study grant. Physician time was donated by the respective VA Medical Centers. Statistical and other central VA personnel were employed by the VA to work on various studies, including this trial.

Role of the Sponsor: The sponsor had no role in the design and conduct of the study; in the collection, analysis, and interpretation of the data; or in the preparation, review, or approval of the manuscript.

McPhee JT, Hill JS, Eslami MH. The impact of gender on presentation, therapy, and mortality of abdominal aortic aneurysm in the United States, 2001-2004.  J Vasc Surg. 2007;45(5):891-899
PubMed   |  Link to Article
EVAR trial participants.  Endovascular aneurysm repair versus open repair in patients with abdominal aortic aneurysm (EVAR trial 1).  Lancet. 2005;365(9478):2179-2186
PubMed   |  Link to Article
Blankensteijn JD, de Jong SE, Prinssen M,  et al.  Two-year outcomes after conventional or endovascular repair of abdominal aortic aneurysms.  N Engl J Med. 2005;352(23):2398-2405
PubMed   |  Link to Article
Lederle FA, Kane RL, MacDonald R, Wilt TJ. Systematic review: repair of unruptured abdominal aortic aneurysm.  Ann Intern Med. 2007;146(10):735-741
PubMed   |  Link to Article
Ballard DJ, Etchason JA, Hilbourne LH,  et al.  Abdominal Aortic Aneurysm Surgery: A Literature Review and Ratings of Appropriateness and Necessity. Santa Monica, CA: RAND Publication; 1992
 Ware JE Jr. SF-36 Health Survey Update. http://www.sf-36.org/tools/sf36.shtml. Accessed August 3, 2009
Diehr P, Patrick DL, McDonell MB, Fihn SD. Accounting for deaths in longitudinal studies using the SF-36.  Med Care. 2003;41(9):1065-1073
PubMed   |  Link to Article
Shaw JW, Johnson JA, Coons SJ. US valuation of the EQ-5D health states: development and testing of the D1 valuation model.  Med Care. 2005;43(3):203-220
PubMed   |  Link to Article
Rosen RC, Cappelleri JC, Smith MD, Lipsky J, Peña BM. Development and evaluation of an abridged, 5-item version of the International Index of Erectile Function (IIEF-5) as a diagnostic tool for erectile dysfunction.  Int J Impot Res. 1999;11(6):319-326
PubMed   |  Link to Article
Johnston KW.Canadian Society for Vascular Surgery Aneurysm Study Group.  Nonruptured abdominal aortic aneurysm: six-year follow-up results from the multicenter prospective Canadian aneurysm study.  J Vasc Surg. 1994;20(2):163-170
PubMed   |  Link to Article
Koskas F, Kieffer E.Association for Academic Research in Vascular Surgery (AURC).  Long-term survival after elective repair of infrarenal abdominal aortic aneurysm.  Ann Vasc Surg. 1997;11(5):473-481
PubMed   |  Link to Article
UK Small Aneurysm Trial Participants.  Mortality results for randomised controlled trial of early elective surgery or ultrasonographic surveillance for small abdominal aortic aneurysms.  Lancet. 1998;352(9141):1649-1655
PubMed   |  Link to Article
Kalbfleish JD, Prentice PL. The Statistical Analysis of Failure Time Data. New York, NY: John Wiley & Sons; 1980
Levey AS, Coresh J, Greene T,  et al.  Using standardized serum creatinine values in the modification of diet in renal disease study equation for estimating glomerular filtration rate.  Ann Intern Med. 2006;145(4):247-254
PubMed   |  Link to Article
Greenhalgh RM, Brown LC, Kwong GP,  et al.  Comparison of endovascular aneurysm repair with open repair in patients with abdominal aortic aneurysm (EVAR trial 1), 30-day operative mortality results.  Lancet. 2004;364(9437):843-848
PubMed   |  Link to Article
Prinssen M, Verhoeven EL, Buth J,  et al.  A randomized trial comparing conventional and endovascular repair of abdominal aortic aneurysms.  N Engl J Med. 2004;351(16):1607-1618
PubMed   |  Link to Article
Aylin P, Bottle A, Majeed A. Use of administrative data or clinical databases as predictors of risk of death in hospital.  BMJ. 2007;334(7602):1044
PubMed   |  Link to Article
Holt PJ, Poloniecki JD, Loftus IM,  et al.  Epidemiological study of the relationship between volume and outcome after abdominal aortic aneurysm surgery in the UK from 2000 to 2005.  Br J Surg. 2007;94(4):441-448
PubMed   |  Link to Article
Lederle FA, Wilson SE, Johnson GR,  et al.  Immediate repair compared with surveillance of small abdominal aortic aneurysms.  N Engl J Med. 2002;346(19):1437-1444
PubMed   |  Link to Article
Hutter MM, Lancaster RT, Henderson WG,  et al.  Comparison of risk-adjusted 30-day postoperative mortality and morbidity in Department of Veterans Affairs hospitals and selected university medical centers.  J Am Coll Surg. 2007;204(6):1115-1126
PubMed   |  Link to Article
 FDA Public Health Notification: Updated Data on Mortality Associated With the Medtronic AneuRx Stent Graft System. http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PublicHealthNotifications/ucm062008.htm. Accessed August 3, 2009
Schermerhorn ML, O'Malley AJ, Jhaveri A,  et al.  Endovascular vs. open repair of abdominal aortic aneurysms in the Medicare population.  N Engl J Med. 2008;358(5):464-474
PubMed   |  Link to Article
Takagi H, Sugimoto M, Kato T,  et al.  Postoperative incision hernia in patients with abdominal aortic aneurysm and aortoiliac occlusive disease.  Eur J Vasc Endovasc Surg. 2007;33(2):177-181
PubMed   |  Link to Article
Prinssen M, Buskens E, Blankensteijn JD.DREAM trial participants.  Quality of life after endovascular and open AAA repair.  Eur J Vasc Endovasc Surg. 2004;27(2):121-127
PubMed   |  Link to Article
Lederle FA, Johnson GR, Wilson SE,  et al.  Quality of life, impotence, and activity level in a randomized trial of immediate repair vs. surveillance of small abdominal aortic aneurysms.  J Vasc Surg. 2003;38(4):745-752
PubMed   |  Link to Article
Xenos ES, Stevens SL, Freeman MB,  et al.  Erectile function after open or endovascular abdominal aortic aneurysm repair.  Ann Vasc Surg. 2003;17(5):530-538
PubMed   |  Link to Article
Koo V, Lau L, McKinley A,  et al.  Pilot study of sexual dysfunction following abdominal aortic aneurysm surgery.  J Sex Med. 2007;4(4 pt 2):1147-1152
PubMed   |  Link to Article
Prinssen M, Buskens E, Nolthenius RP,  et al.  Sexual dysfunction after conventional and endovascular AAA repair.  J Endovasc Ther. 2004;11(6):613-620
PubMed   |  Link to Article

Figures

Place holder to copy figure label and caption
Figure 1. Flow Diagram of Study Patients
Graphic Jump Location

AAA indicates abdominal aortic aneurysm.

Place holder to copy figure label and caption
Figure 2. Kaplan-Meier Curve of Cumulative Probabilities of Death From Time of Randomization
Graphic Jump Location

There was no significant difference in cumulative mortality for open vs endovascular repair (hazard ratio, 0.7; 95% confidence interval, 0.4-1.1; log-rank P  = .13).

Place holder to copy figure label and caption
Figure 3. Hazard Ratios for Death According to Baseline Characteristics
Graphic Jump Location

AAA indicates abdominal aortic aneurysm; CI, confidence interval. Size of the data markers is relative to the number of deaths in that subgroup. All P > .10 for interaction with treatment effect. For surgical risk (RAND score), see online eAppendix.5

Tables

Table Graphic Jump LocationTable 1. Patient Characteristics at the Time of Randomizationa
Table Graphic Jump LocationTable 2. Details of Aneurysm Repair by Randomly Assigned Groupa
Table Graphic Jump LocationTable 4. Quality of Life and Erectile Dysfunctiona

References

McPhee JT, Hill JS, Eslami MH. The impact of gender on presentation, therapy, and mortality of abdominal aortic aneurysm in the United States, 2001-2004.  J Vasc Surg. 2007;45(5):891-899
PubMed   |  Link to Article
EVAR trial participants.  Endovascular aneurysm repair versus open repair in patients with abdominal aortic aneurysm (EVAR trial 1).  Lancet. 2005;365(9478):2179-2186
PubMed   |  Link to Article
Blankensteijn JD, de Jong SE, Prinssen M,  et al.  Two-year outcomes after conventional or endovascular repair of abdominal aortic aneurysms.  N Engl J Med. 2005;352(23):2398-2405
PubMed   |  Link to Article
Lederle FA, Kane RL, MacDonald R, Wilt TJ. Systematic review: repair of unruptured abdominal aortic aneurysm.  Ann Intern Med. 2007;146(10):735-741
PubMed   |  Link to Article
Ballard DJ, Etchason JA, Hilbourne LH,  et al.  Abdominal Aortic Aneurysm Surgery: A Literature Review and Ratings of Appropriateness and Necessity. Santa Monica, CA: RAND Publication; 1992
 Ware JE Jr. SF-36 Health Survey Update. http://www.sf-36.org/tools/sf36.shtml. Accessed August 3, 2009
Diehr P, Patrick DL, McDonell MB, Fihn SD. Accounting for deaths in longitudinal studies using the SF-36.  Med Care. 2003;41(9):1065-1073
PubMed   |  Link to Article
Shaw JW, Johnson JA, Coons SJ. US valuation of the EQ-5D health states: development and testing of the D1 valuation model.  Med Care. 2005;43(3):203-220
PubMed   |  Link to Article
Rosen RC, Cappelleri JC, Smith MD, Lipsky J, Peña BM. Development and evaluation of an abridged, 5-item version of the International Index of Erectile Function (IIEF-5) as a diagnostic tool for erectile dysfunction.  Int J Impot Res. 1999;11(6):319-326
PubMed   |  Link to Article
Johnston KW.Canadian Society for Vascular Surgery Aneurysm Study Group.  Nonruptured abdominal aortic aneurysm: six-year follow-up results from the multicenter prospective Canadian aneurysm study.  J Vasc Surg. 1994;20(2):163-170
PubMed   |  Link to Article
Koskas F, Kieffer E.Association for Academic Research in Vascular Surgery (AURC).  Long-term survival after elective repair of infrarenal abdominal aortic aneurysm.  Ann Vasc Surg. 1997;11(5):473-481
PubMed   |  Link to Article
UK Small Aneurysm Trial Participants.  Mortality results for randomised controlled trial of early elective surgery or ultrasonographic surveillance for small abdominal aortic aneurysms.  Lancet. 1998;352(9141):1649-1655
PubMed   |  Link to Article
Kalbfleish JD, Prentice PL. The Statistical Analysis of Failure Time Data. New York, NY: John Wiley & Sons; 1980
Levey AS, Coresh J, Greene T,  et al.  Using standardized serum creatinine values in the modification of diet in renal disease study equation for estimating glomerular filtration rate.  Ann Intern Med. 2006;145(4):247-254
PubMed   |  Link to Article
Greenhalgh RM, Brown LC, Kwong GP,  et al.  Comparison of endovascular aneurysm repair with open repair in patients with abdominal aortic aneurysm (EVAR trial 1), 30-day operative mortality results.  Lancet. 2004;364(9437):843-848
PubMed   |  Link to Article
Prinssen M, Verhoeven EL, Buth J,  et al.  A randomized trial comparing conventional and endovascular repair of abdominal aortic aneurysms.  N Engl J Med. 2004;351(16):1607-1618
PubMed   |  Link to Article
Aylin P, Bottle A, Majeed A. Use of administrative data or clinical databases as predictors of risk of death in hospital.  BMJ. 2007;334(7602):1044
PubMed   |  Link to Article
Holt PJ, Poloniecki JD, Loftus IM,  et al.  Epidemiological study of the relationship between volume and outcome after abdominal aortic aneurysm surgery in the UK from 2000 to 2005.  Br J Surg. 2007;94(4):441-448
PubMed   |  Link to Article
Lederle FA, Wilson SE, Johnson GR,  et al.  Immediate repair compared with surveillance of small abdominal aortic aneurysms.  N Engl J Med. 2002;346(19):1437-1444
PubMed   |  Link to Article
Hutter MM, Lancaster RT, Henderson WG,  et al.  Comparison of risk-adjusted 30-day postoperative mortality and morbidity in Department of Veterans Affairs hospitals and selected university medical centers.  J Am Coll Surg. 2007;204(6):1115-1126
PubMed   |  Link to Article
 FDA Public Health Notification: Updated Data on Mortality Associated With the Medtronic AneuRx Stent Graft System. http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PublicHealthNotifications/ucm062008.htm. Accessed August 3, 2009
Schermerhorn ML, O'Malley AJ, Jhaveri A,  et al.  Endovascular vs. open repair of abdominal aortic aneurysms in the Medicare population.  N Engl J Med. 2008;358(5):464-474
PubMed   |  Link to Article
Takagi H, Sugimoto M, Kato T,  et al.  Postoperative incision hernia in patients with abdominal aortic aneurysm and aortoiliac occlusive disease.  Eur J Vasc Endovasc Surg. 2007;33(2):177-181
PubMed   |  Link to Article
Prinssen M, Buskens E, Blankensteijn JD.DREAM trial participants.  Quality of life after endovascular and open AAA repair.  Eur J Vasc Endovasc Surg. 2004;27(2):121-127
PubMed   |  Link to Article
Lederle FA, Johnson GR, Wilson SE,  et al.  Quality of life, impotence, and activity level in a randomized trial of immediate repair vs. surveillance of small abdominal aortic aneurysms.  J Vasc Surg. 2003;38(4):745-752
PubMed   |  Link to Article
Xenos ES, Stevens SL, Freeman MB,  et al.  Erectile function after open or endovascular abdominal aortic aneurysm repair.  Ann Vasc Surg. 2003;17(5):530-538
PubMed   |  Link to Article
Koo V, Lau L, McKinley A,  et al.  Pilot study of sexual dysfunction following abdominal aortic aneurysm surgery.  J Sex Med. 2007;4(4 pt 2):1147-1152
PubMed   |  Link to Article
Prinssen M, Buskens E, Nolthenius RP,  et al.  Sexual dysfunction after conventional and endovascular AAA repair.  J Endovasc Ther. 2004;11(6):613-620
PubMed   |  Link to Article
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