As compared with open repair, endovascular repair of abdominal aortic aneurysm is associated with lower short-term rates of death and complications. The survival advantage is more durable among older patients. Late reinterventions related to abdominal aortic aneurysm are more common after endovascular repair but are balanced by an increase in laparotomy-related reinterventions and hospitalizations after open surgery.

INTRODUCTION AND OBJECTIVES The impact of risk factors upon perioperative mortality might differ for patients undergoing open versus endovascular repair (EVAR) of abdominal aortic aneurysms (AAA). In order to investigate this, we developed a differential predictive model of perioperative mortality after AAA repair. METHODS A total of 45,660 propensity score matched Medicare beneficiaries undergoing elective open or endovascular AAA repair from 2001–2004 were studied. Using half the dataset we developed a multiple logistic regression model for a matched cohort of open and EVAR patients and used this to derive an easily evaluable risk prediction score. The remainder of the dataset formed a validation cohort used to confirm results. RESULTS The derivation cohort included 11,415 open and 11,415 endovascular repairs. Perioperative mortality was 5.3% and 1.8% respectively. Independent predictors of mortality (RR, 95% CI) were open repair (3.2, 2.7–3.8), age (71–75 years 1.2, 0.9–1.6; 76–80 years 1.9, 1.4–2.5; >80 years 3.1, 2.4–4.2), female sex (1.5, 1.3–1.8), dialysis (2.6, 1.5–4.6), chronic renal insufficiency (2.0, 1.6–2.6), congestive heart failure (1.7, 1.5–2.1), and vascular disease (1.3, 1.2–1.6). There were no differential predictors of mortality across the two procedures. A simple scoring system was developed from a logistic regression model fit to both endovascular and open patients (area under the ROC curve of 72.6) from which low, medium, and high risk groups were developed. The absolute predicted mortality ranged from 0.7% for an EVAR patient ≤ 70 years of age with no comorbidities to 38% for an open patient > 80 with all the comorbidities considered. Although relative risk was similar among age groups, the absolute difference was greater for older patients (with higher baseline risk). CONCLUSIONS Mortality after AAA repair is predicted by comorbidities, sex, and age and these predictors have similar effects for both methods of AAA repair. This simple scoring system can predict repair mortality for both treatment options and thus may help guide clinical decisions.

Objectives Endovascular abdominal aortic aneurysm repair (EVAR) is increasingly used for emergent treatment of ruptured abdominal aortic aneurysm (rAAA). We sought to compare the perioperative and long-term mortality, procedure-related complications and rates of re-intervention of EVAR versus open aortic repair of rAAA in Medicare beneficiaries. Methods We examined perioperative and long-term mortality and complications after EVAR or open aortic repair performed for rAAA in all traditional Medicare beneficiaries discharged from a US hospital from 2001–2008. Patients were propensity score matched on baseline demographics, coexisting conditions, admission source, and hospital volume of rAAA repair and sensitivity analyses were performed to evaluate the impact of bias that might have resulted from unmeasured confounders Results Of 10,998 patients with repaired rAAA, 1126 underwent EVAR and 9872 underwent open repair. Propensity score matching yielded 1099 patient pairs. The average age was 78 years, and 72.4% were male. Perioperative mortality for EVAR and open repair were 33.8% and 47.7% respectively (p<0.001) and this difference persisted for more than four years. EVAR patients had higher rates of AAA-related reinterventions when compared with open repair patients (endovascular reintervention at 36 months 10.9% vs 1.5%, p<0.001), whereas open patients had more laparotomy related complications (incisional hernia repair at 36 months 1.8% vs. 6.2% p<0.001, all surgical complications at 36 months 4.4% vs. 9.1%, p<0.001). Use of EVAR for rAAA has increased from 6% of cases in 2001 to 31% of cases in 2008, while over the same time period overall 30-day mortality for admission for rAAA regardless of treatment has decreased from 55.8% to 50.9%. Conclusions EVAR for rAAA is associated with lower perioperative and long term mortality in Medicare beneficiaries. Increasing adoption of EVAR for rAAA is associated with an overall decrease in mortality of patients hospitalized for rAAA over the last decade.

Objective To examine the modern epidemiology of abdominal aortic aneurysm (AAA) rupture and short-term AAA-related mortality after the introduction of endovascular aneurysm repair (EVAR). Background Prior epidemiologic studies have demonstrated stable rates of AAA repair, repair mortality, and AAA rupture. Recently, EVAR has been introduced as a less invasive treatment method and its use has expanded to over 75% of elective AAA repairs. Methods We identified Medicare beneficiaries undergoing AAA repair and those hospitalized with a ruptured AAA during the period 1995–2008 and calculated standardized annual rates of AAA-related deaths due to either elective repair or rupture. Results 338,278 patients underwent intact AAA repair over the study period. There were 69,653 patients with AAA rupture of whom 47,524 underwent repair. Intact repair rates increased substantially in those over age 80 (57.7 to 92.3 per 100,000, P<0.001), but decreased in those aged 65–74 (81.8 to 68.9, P<0.001). A decline in ruptures with and without repair was seen in all age groups. By 2008, 77% of all intact repairs and 31% of all rupture repairs were performed with EVAR (P<0.001). Operative mortality declined over the study period for both intact (4.9% to 2.4%, P<0.001) and ruptured (44.1% to 36.3%, P<0.001) AAA repair. Short-term AAA-related deaths decreased by more than half (26.1 to 12.1 per 100,000, P<0.001) with the greatest decline occurring in those over age 80 (53.7 to 27.3, P<0.001). Conclusions A recent decline in AAA rupture and short-term AAA-related mortality is demonstrated and likely related in part to the introduction and expansion of EVAR. This is due to decreased deaths from ruptures (with and without repair) and decreased mortality with intact repairs, particularly in patients over age 80.

Objectives Late survival is similar after EVAR and open AAA repair despite a perioperative benefit with EVAR. AAA-related reinterventions are more common after EVAR while laparotomy related reinterventions are more common after open repair. The impact of reinterventions on survival, however, is unknown. We therefore evaluate the rate of reinterventions and readmission after initial AAA repair along with 30-day mortality and the effect upon long term survival. Methods We identified AAA and laparotomy-related reinterventions for propensity score matched cohorts of Medicare beneficiaries (n=45,652) undergoing EVAR and open repair from 2001-2004. Follow-up was up to 6 years. Hospitalizations for ruptured AAA without repair and for bowel obstruction or ventral hernia without abdominal surgery were also recorded. Event rates were calculated per year and are also presented through 6 years of follow-up as events per 100 person years. Thirty day mortality was calculated for each reintervention or readmission. Results Through 6 years, overall reinterventions or readmissions were similar between repair methods but slightly more common after EVAR (7.6 vs. 7.0 per 100 person years, RR 1.1, P < .001). Overall 30 day mortality with any reintervention or readmission was 9.1%. EVAR patients had more ruptures (0.50 vs. 0.09, RR 5.7, P < .001) with a mortality of 28%, but these were uncommon. EVAR patients also had more AAA-related reinterventions through 6 years (3.7 vs. 0.9, RR 4.0, P < .001) (mortality 5.6%), the majority of which were minor endovascular reinterventions (2.4 vs. 0.2, RR 11.4, P < .001) with a 30 day mortality of 3.0%. However, minor open (0.8 vs. 0.5, RR 1.4, P < .001) (mortality 6.9%) and major reinterventions (0.4 vs. 0.2, RR 2.4, P < .001) (mortality 12.1%) were also more common after EVAR than open repair. Conversely, EVAR patients had fewer laparotomy related reinterventions than open patients (1.4 vs. 3.0, RR 0.5, P < .001) (mortality 8.1%) and readmissions without surgery (2.0 vs. 2.7, RR 0.7, P < .001) (mortality 10.9%). Overall, reinterventions or readmission accounted for 9.6% of all EVAR deaths and 7.6% of all open repair deaths in the follow-up period (P < .001). Conclusions Reintervention and readmission are slightly higher after EVAR. Survival is negatively impacted by reintervention or readmission after both EVAR and open surgery, which likely contributes to the erosion of the survival benefit of EVAR over time.