Racial and sex disparities in inpatient outcomes of patients with ruptured abdominal aortic aneurysms in the United States.

BACKGROUND: Ruptured abdominal aortic aneurysm (AAA) is a medical emergency that requires immediate surgical intervention. The aim of this analysis was to identify the sex- and race-specific disparities that exist in outcomes of patients hospitalized with this condition in the United States using the National Inpatient Sample (NIS) to identify targets for improvement and support of specific patient populations. METHODS: In this descriptive, retrospective study, we analyzed the patients admitted with a primary diagnosis of ruptured AAA between January 1, 2016, and December 31, 2020, using the NIS database. We compared demographics, comorbidities, and in-hospital outcomes in AAA patients, and compared these results between different racial groups and sexes. RESULTS: A total of 22,395 patients with ruptured AAA were included for analysis. Of these, 16,125 patients (72.0%) were male, and 6270 were female (28.0%). The majority of patients (18,655 [83.3%]) identified as Caucasian, with the remaining patients identifying as African American (1555 [6.9%]), Hispanic (1095 [4.9%]), Asian or Pacific Islander (470 [2.1%]), or Native American (80 [0.5%]). Females had a higher risk of mortality than males (OR, 1.7; 95% confidence interval [CI], 1.45-1.96; P < .001) and were less likely to undergo endovascular aortic repair (OR, 0.70; 95% CI, 0.61-0.81; P < .001) or fenestrated endovascular aortic repair (OR, 0.71; 95% CI, 0.55-0.91; P = .007). Relative to Caucasian race, patients who identified as African American had a lower risk of inpatient mortality (OR, 0.50; 95% CI, 0.37-0.68; P < .001). CONCLUSIONS: In this retrospective study of the NIS database from 2016 to 2020, females were less likely to undergo endovascular intervention and more likely to die during their initial hospitalization. African American patients had lower rates in-hospital mortality than Caucasian patients, despite a higher burden of comorbidities. Future studies are needed to elucidate the potential factors affecting racial and sex disparities in ruptured AAA outcomes, including screening practices, rupture risk stratification, and more personalized guidelines for both elective and emergent intervention.

Renin-Angiotensin-Aldosterone System Inhibitors Are Associated With Favorable Outcomes Compared to Beta Blockers in Reducing Mortality Following Abdominal Aneurysm Repair.

Background The best medical therapy to control hypertension following abdominal aortic aneurysm repair is yet to be determined. We therefore examined whether treatment with renin-angiotensin-aldosterone system inhibitors (RAASIs) versus beta blockers influenced postoperative and 1-year clinical end points following abdominal aortic aneurysm repair in a Medicare-linked database. Methods and Results All patients with hypertension undergoing endovascular aneurysm repair and open aneurysm repair in the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database between 2003 and 2018 were included. Patients were divided into 2 groups based on their preoperative and discharge medications, either RAASIs or beta blockers. Our cohort included 8789 patients, of whom 3523 (40.1%) were on RAASIs, and 5266 (59.9%) were on beta blockers. After propensity score matching, there were 3053 matched pairs of patients in each group. After matching, RAASI use was associated with lower risk of postoperative mortality (odds ratio [OR], 0.3 [95% CI, 0.1-0.6]), myocardial infarction (OR, 0.1 [95% CI, 0.03-0.6]), and nonhome discharge (OR, 0.6 [95% CI, 0.5-0.7]). Before propensity score matching, RAASI use was associated with lower 1-year mortality (hazard ratio [HR], 0.4 [95% CI, 0.4-0.5]) and lower risk of aneurysmal rupture (HR, 0.7 [95% CI, 0.5-0.9]). These results persisted after propensity score matching for mortality (HR, 0.4 [95% CI, 0.4-0.5]) and aneurysmal rupture (HR, 0.7 [95% CI, 0.5-0.9]). Conclusions In this large contemporary retrospective cohort study, RAASI use was associated with favorable postoperative outcomes compared with beta blockers. It was also associated with lower mortality and aneurysmal rupture at 1 year of follow-up.

Long-term Mortality and Reintervention After Repair of Ruptured Abdominal Aortic Aneurysms Using VQI-matched Medicare Claims.

OBJECTIVE: The objective of this study was to compare endovascular aortic aneurysm repair (EVAR) versus open aortic repair (OAR) on mortality and reintervention after ruptured infrarenal abdominal aortic aneurysm (rAAA) repair in the Vascular Quality Initiative (VQI). BACKGROUND: The optimal treatment modality for rAAA remains debated, with little data on long-term comparisons. METHODS: VQI rAAA repairs (2004-2018) were matched with Medicare claims (VQI-VISION). Primary outcomes were in-hospital and long-term mortality. Secondary outcome was reintervention. Inverse probability weighting was used to adjust for treatment selection, and Cox Proportional Hazards models and negative binomial regressions were used for analysis. Landmark analysis was performed among patients surviving hospital discharge. RESULTS: Among 1885 VQI/Medicare rAAA patients, 790 underwent OAR, and 1095 underwent EVAR. Median age was 76 years; 73% were male. Inverse probability weighting produced comparable groups. In-hospital mortality was lower after EVAR versus OAR (21% vs 37%, odds ratio: 0.52, 95% CI, 0.4-0.7). One-year mortality rates were lower for EVAR versus OAR [hazard ratio (HR) 0.74, 95% CI, 0.6-0.9], but not statistically different after 1 year (HR: 0.95, 95% CI, 0.8-1.2). This implies additional benefits to EVAR in the short term. Reintervention rates were higher after EVAR than OAR at 2 and 5 years (rate ratio: 1.79 95% CI, 1.2-2.7 and rate ratio:2.03 95% CI, 1.4-3.0), but not within the first year. Reintervention was associated with higher mortality risk for both OAR (HR: 1.66 95% CI, 1.1-2.5) and EVAR (HR: 2.14 95% CI, 1.6-2.9). Long-term mortality was similar between repair types (HR: 0.99, 95% CI, 0.8-1.2). CONCLUSIONS: Within VQI/Medicare patients undergoing rAAA repair, the perioperative mortality rate favors EVAR but equalizes after 1 year. Reinterventions were more common after EVAR and were associated with higher mortality regardless of treatment.

Racial disparities in treatment of ruptured abdominal aortic aneurysms.

OBJECTIVE: The Society for Vascular Surgery has recommended immediate transfer of patients with ruptured abdominal aortic aneurysms (rAAAs) to a regional center when feasible. However, Black patients might be less likely to be transferred and more likely to be turned down for repair. We, therefore, examined the transfer rates, turndown rates, and outcomes for Black vs White patients presenting with rAAAs in two large databases. METHODS: We examined all rAAA repairs in the Vascular Quality Initiative from 2003 to 2020 to evaluate the transfer rates and outcomes for Black vs White patients. We used the National Inpatient Sample from 2004 to 2015 to examine the turndown rates. Mixed effects logistic regression, Cox regression, and marginal effects modeling were used to study the interaction between race, insurance status, surgery type (open repair vs endovascular aortic aneurysm repair), and hospital volume. RESULTS: We identified 4935 patients with rAAAs in the Vascular Quality Initiative (6.2% Black) and 48,489 in the National Inpatient Sample (6.0% Black). The rates of transfer were high; however, Black patients were significantly less likely to undergo transfer before repair compared with White patients (49% Black vs 62% White; P = .002). The result was consistent in both crude and adjusted analyses when considering only stable patients and was not modified by insurance status, surgery type, or hospital volume. No significant differences were found in perioperative mortality (22% vs 26%; P = .098) or complications (52% vs 52%; P = .64). However, Black patients were significantly more likely to be turned down for repair (37% vs 28%; odds ratio, 1.5; 95% confidence interval, 1.2-1.9; P < .001). A significant interaction was found between race and insurance status with respect to turndown. Patients with private insurance had undergone surgery at a similar rate, regardless of race. However, among patients with Medicare or Medicaid/self-pay, Black patients were less likely than were White patients to undergo repair (Medicare, 64% vs 72%; P = .001; Medicaid/self-pay, 43% vs 61%; P = .031). Patients with Medicaid/self-pay were also less likely to undergo repair than were patients of the same race with either Medicare or private insurance (P < .05). CONCLUSIONS: We found that Black patients with rAAAs are poorly served by the current systems of interhospital transfer in the United States, because they less often undergo transfer before repair. Although the postoperative outcomes appeared similar, this finding could be falsely optimistic, because Black patients, especially the underinsured, were turned down for repair more often even after adjustment. Significant work is needed to better understand the reasons underlying these disparities and identify the targets to improve the care of Black patients with rAAAs.

Long-term Outcomes Associated With Open vs Endovascular Abdominal Aortic Aneurysm Repair in a Medicare-Matched Database.

Importance: Endovascular aneurysm repair is associated with a significant reduction in perioperative mortality and morbidity compared with open aneurysm repair in the treatment of abdominal aortic aneurysm. However, this benefit decreases over time owing to increased reinterventions and late aneurysm rupture after endovascular repair. Objective: To compare long-term outcomes of endovascular vs open repair of abdominal aortic aneurysm. Design, Setting, and Participants: This multicenter retrospective cohort study used deidentified data with 6-year follow-up from the Medicare-matched Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database. Patients undergoing first-time elective endovascular or open abdominal aortic aneurysm repair from 2003 to 2018 were propensity score matched. Patients with ruptured abdominal aortic aneurysm, concomitant procedures, or prior history of abdominal aortic aneurysm repair, were excluded. Data were analyzed from January 1, 2003, to December 31, 2018. Exposures: First-time elective endovascular or open repair for abdominal aortic aneurysm. Main Outcomes and Measures: The primary long-term outcome of interest was 6-year all-cause mortality, rupture, and reintervention. Secondary outcomes included 30-day mortality and perioperative complications. Results: Among a total of 32 760 patients (median [IQR] age, 75 [70-80] years; 25 706 [78.5%] men) who underwent surgical abdominal aortic aneurysm repair, 28 281 patients underwent endovascular repair and 4479 patients underwent open repair. After propensity score matching, there were 2852 patients in each group. Open repair was associated with significantly lower 6-year mortality compared with endovascular repair (548 deaths [35.6%] vs 608 deaths [41.2%]; hazard ratio [HR], 0.83; 95% CI, 0.74-0.94; P = .002), with increases in mortality starting from 1 to 2 years (84 deaths [4.3%] vs 126 deaths [6.7%]; HR, 0.63; 95% CI, 0.48-0.83; P = .001) and 2 to 6 years (211 deaths [25.8%] vs 241 deaths [30.6%]; HR, 0.73; 95% CI, 0.61-0.88; P = .001). Open repair, compared with endovascular repair, also was associated with significantly lower rates of 6-year rupture (117 participants [5.8%] vs 149 participants [8.3%]; HR, 0.76; 95% CI, 0.60-0.97; P < .001) and reintervention (190 participants [11.6%] vs 267 participants [16.0%]; HR, 0.67; 95% CI, 0.55-0.80; P < .001). Open repair was associated with significantly higher odds of 30-day mortality (OR, 3.56; 95% CI, 2.41-5.26; P < .001) and complications. Conclusions and Relevance: These findings suggest that overall mortality after elective abdominal aortic aneurysm repair was higher with endovascular repair than open repair despite reduced 30-day mortality and perioperative morbidity after endovascular repair. Endovascular repair additionally was associated with significantly higher rates of long-term rupture and reintervention. These findings emphasize the importance of careful patient selection and long-term follow-up surveillance for patients who undergo endovascular repair.

The impact of hospital size on national trends and outcomes in isolated open proximal aortic surgery.

OBJECTIVE: To determine the impact of hospital size on national trend estimates of isolated open proximal aortic surgery for benchmarking hospital performance. METHODS: Patients age >18 years who underwent isolated open proximal aortic surgery for aneurysm and dissection from 2002 to 2014 were identified using the National Inpatient Sample. Concomitant valvular, vessel revascularization, re-do procedures, endovascular, and surgery for descending and thoracoabdominal aorta were excluded. Discharges were stratified by hospital size and analyzed using trend, multivariable regression, propensity-score matching analysis. RESULTS: Over a 13-year period, 53,657 isolated open proximal aortic operations were performed nationally. Although the total number of operations/year increased (∼2.9%/year increase) and overall in-hospital mortality decreased (∼4%/year; both P < .001 for trend), these did not differ by hospital size (P > .05). Large hospitals treated more sicker and older patients but had shorter length of stay and lower hospital costs (both P < .001). Even after propensity-score matching, large hospital continued to demonstrate superior in-hospital outcomes, although only statistically for major in-hospital cardiac complications compared with non-large hospitals. In our subgroup analysis of dissection versus non-dissection cohort, in-hospital mortality trends decreased only in the non-dissection cohort (P < .01) versus dissection cohort (P = .39), driven primarily by the impact of large hospitals (P < .01). CONCLUSIONS: This study demonstrates increasing volume and improving outcomes of isolated open proximal aortic surgeries nationally over the last decade regardless of hospital bed size. Moreover, the resource allocation of sicker patients to larger hospital resulted shorter length of stay and hospital costs, while maintaining similar operative mortality to small- and medium-sized hospitals.

Outcomes and Predictors of Mortality in a Belgian Population of Patients Admitted with Ruptured Abdominal Aortic Aneurysm and Treated by Open Repair in the Contemporary Era.

BACKGROUND: Abdominal aortic aneurysm (AAA) rupture is a serious condition that results in extremely high mortality rates. Some improvements in outcome have been reported during the last 2 decades. The objective of the present study was to determine the overall and operative (by open repair) mortality related to ruptured AAA in the contemporary era and to identify preoperative, intraoperative, and early postoperative parameters associated with poor outcomes. METHODS: We performed a retrospective review of all consecutive patients admitted to our single institution with a diagnosis of ruptured AAA between 2004 and 2013. A total of 103 parameters, including demographic characteristics, medical history, clinical and biological parameters, cardiovascular risk factors, emergency level, diagnostic modalities, time from symptoms to diagnosis and treatment, type of operative procedure and postoperative complications, were analyzed. The primary endpoint considered in this study was the cumulative incidence rate of mortality. The secondary endpoint was the identification, by logistic regression methods, of risk factors for overall mortality as well as for operative, and postoperative mortality. RESULTS: Within our study period, 104 patients were admitted for a ruptured AAA. The majority of patients (84.6%) were male, and the AAA was known in 34.6% of the patients. Rupture occurred for a maximal diameter lower than 55 mm in 25% of the female population, compared to 5.7% of the male population (P = 0.030). The proportions of admitted patients who died before (preoperative mortality), during (intraoperative mortality) or after (postoperative hospital mortality) surgery was 17.3%, 16.3%, and 18.3%, respectively, yielding a cumulative in-hospital mortality of 51.9%. In the multivariate analysis, age ≥ 80 (P = 0.001), myocardial ischemia on the admission ECG (P = 0.046), and management by the physician response unit (P = 0.002) were the only preoperative parameters associated with a higher risk of hospital mortality. Four risk factors were found to be associated with a higher risk of postoperative mortality in the multivariate analysis, and all patients presenting with 3 or more of these risk factors (n = 5) died. CONCLUSIONS: The overall mortality of ruptured AAA in a contemporary cohort of patients who underwent open repair remains high and does not seem to have decreased during recent decades. Ruptures occur at smaller diameters in women than in men, supporting a lower threshold for intervention in women with known AAA. We developed risk scores to predict the mortality of patients with rAAA at different times of their hospital course. The validity of these scores should be assessed in prospective clinical studies.

Lipoprotein(a) levels and risk of abdominal aortic aneurysm in the Women's Health Initiative.

OBJECTIVE: Few studies have prospectively examined the associations of lipoprotein(a) [Lp(a)] levels with the risk of abdominal aortic aneurysm (AAA), especially in women. Accounting for commonly recognized risk factors, we investigated the baseline Lp(a) levels and the risk of AAA among postmenopausal women participating in the ongoing national Women's Health Initiative. METHODS: Women's Health Initiative participants with baseline Lp(a) levels available who were beneficiaries of Medicare parts A and B fee-for-service at study enrollment or who had aged into Medicare at any point were included. Participants with missing covariate data or known AAA at baseline were excluded. Thoracic aneurysms were excluded owing to the different pathophysiology. The AAA cases and interventions were identified using the International Classification of Diseases, 9th and 10th revision, codes and Current Procedural Terminology codes from claims data. Hazard ratios were computed using Cox proportional hazard models according to the quintiles of Lp(a). RESULTS: The mean age of the 6615 participants included in the analysis was 65.3 years. Of the 6615 participants, 66.6% were non-Hispanic white, 18.9% were black, 7% were Hispanic and 4.7% were Asian/Pacific Islander. Compared with the participants in the lowest Lp(a) quintile, those in higher quintiles were more likely to be overweight, black, and former or current smokers, to have hypertension, hyperlipidemia, and a history of cardiovascular disease, and to use menopausal hormone therapy and statins. During 65,476 person-years of follow-up, with a median of 10.4 years, 415 women had been diagnosed with an AAA and 36 had required intervention. More than one half had required intervention for a ruptured AAA. We failed to find a statistically significant association between Lp(a) levels and incident AAA. Additional sensitivity analyses stratified by race, with exclusion of statin users and alternative categorizations of Lp(a) using log-transformed levels, tertiles, and a cutoff of >50 mg/dL, were conducted, which did not reveal any significant associations. CONCLUSIONS: We found no statistically significant association between Lp(a) levels and the risk of AAA in a large and well-phenotyped sample of postmenopausal women. Women with high Lp(a) levels were more likely to be overweight, black, and former or current smokers, and to have hypertension, hyperlipidemia, and a history of cardiovascular disease, or to use hormone therapy and statins compared with those with lower Lp(a) levels. These findings differ from previous prospective, case-control, and meta-analysis studies that had supported a significant relationship between higher Lp(a) levels and an increased risk of AAA. Differences in the association could have resulted from study limitations or sex differences.

Mid-Term Survival after Thoracic Endovascular Aortic Repair by Indication in the Medicare Population.

BACKGROUND: Thoracic endovascular aortic repair (TEVAR) is indicated for treatment of aneurysms, dissections, and traumatic injury. We describe mid-term mortality and reintervention rates in Medicare beneficiaries undergoing TEVAR. STUDY DESIGN: Patients who underwent TEVAR between 2006 and 2014 were identified by CPT codes in a 20% Medicare sample. Indication for aortic repair (aneurysm, dissection, trauma) was ascertained via ICD-9 codes. Follow-up was evaluated until 2015. Kaplan-Meier survival analysis and Cox regression were used to compare mortality, with reintervention and mortality rates expressed as a composite outcome in a hazard ratio with 95% confidence interval (hazard ratio [HR] 95% CI). RESULTS: There were 3,095 patients who underwent TEVAR during the study period: 1,465 (47%) for aneurysm, 1,448 (47%) for dissection, and 182 (5.9%) for trauma. Mean patient age was 74.4 years, and 44.5% were female. Median follow-up was 2.7 years. The overall 30-day, 1-year, and 5-year, and 8-year survival rates were 93%, 78%, 49%, and 33%, respectively. Thirty-day mortality was highest in traumatic indications, but overall mortality was highest in patients undergoing TEVAR for aneurysm. Freedom from combined reintervention and mortality at 30 days, 1 year, 5 years, and 8 years was 89%, 73%, 43%, and 29%, respectively. Reintervention was highest in patients undergoing TEVAR for dissection (12.8%), followed by aneurysm (10.0%) and trauma (5.5%). Advanced age (HR 1.03 per year, 95% CI 1.02-1.03), congestive heart failure (CHF) (HR 1.48, 95% CI 1.33-1.65), dementia (HR 1.40, 95% CI 1.14-1.28), and rupture (HR 1.38, 95% CI 1.24-1.54) were associated with mortality. CONCLUSIONS: Midterm survival is lower in patients who undergo TEVAR for dissection and aneurysm compared with trauma. Aneurysmal disease, advanced age, CHF, dementia, and aortic rupture are associated with mortality and reintervention in TEVAR.

Biomechanical Assessment Predicts Aneurysm Related Events in Patients with Abdominal Aortic Aneurysm.

OBJECTIVE: To test whether aneurysm biomechanical ratio (ABR; a dimensionless ratio of wall stress and wall strength) can predict aneurysm related events. METHODS: In a prospective multicentre clinical study of 295 patients with an abdominal aortic aneurysm (AAA; diameter ≥ 40 mm), three dimensional reconstruction and computational biomechanical analyses were used to compute ABR at baseline. Participants were followed for at least two years and the primary end point was the composite of aneurysm rupture or repair. RESULTS: The majority were male (87%), current or former smokers (86%), most (72%) had hypertension (mean ± standard deviation [SD] systolic blood pressure 140 ± 22 mmHg), and mean ± SD baseline diameter was 49.0 ± 6.9 mm. Mean ± SD ABR was 0.49 ± 0.27. Participants were followed up for a mean ± SD of 848 ± 379 days and rupture (n = 13) or repair (n = 102) occurred in 115 (39%) cases. The number of repairs increased across tertiles of ABR: low (n = 24), medium (n = 34), and high ABR (n = 44) (p = .010). Rupture or repair occurred more frequently in those with higher ABR (log rank p = .009) and ABR was independently predictive of this outcome after adjusting for diameter and other clinical risk factors, including sex and smoking (hazard ratio 1.41; 95% confidence interval 1.09-1.83 [p = .010]). CONCLUSION: It has been shown that biomechanical ABR is a strong independent predictor of AAA rupture or repair in a model incorporating known risk factors, including diameter. Determining ABR at baseline could help guide the management of patients with AAA.

Editor's Choice - Assessment of Correlation Between Mean Size of Infrarenal Abdominal Aortic Aneurysm at Time of Intact Repair Against Repair and Rupture Rate in Nine Countries.

OBJECTIVE: This study aimed to analyse the mean abdominal aortic aneurysm (AAA) diameter for repair in nine countries, and to determine variation in mean AAA diameter for elective AAA repair and its relationship to rupture AAA repair rates and aneurysm related mortality in corresponding populations. METHODS: Data on intact (iAAA) and ruptured infrarenal AAA (rAAA) repair for the years 2010-2012 were collected from Denmark, England, Finland, Germany, Hungary, New Zealand, Norway, Sweden, and the USA. The rate of iAAA repair and rAAA per 100 000 inhabitants above 59 years old, mean AAA diameter for iAAA repair and rAAA repair, and the national rates of rAAA were assessed. National cause of death statistics were used to estimate aneurysm related mortality. Direct standardisation methods were applied to the national mortality data. Logistic regression and analysis of variance model adjustments were made for age groups, sex, and year. RESULTS: There was a variation in the mean diameter of iAAA repair (n = 34 566; range Germany = 57 mm, Denmark = 68 mm). The standardised iAAA repair rate per 100000 inhabitants varied from 10.4 (Hungary) to 66.5 (Norway), p<.01, and the standardised rAAA repair rate per 100 000 from 5.8 (USA) to 16.9 (England), p<.01. Overall, there was no significant correlation between mean diameter of iAAA repair and standardised iAAA rate (r2 = 0.04, p = .3). There was no significant correlation between rAAA repair rate (n = 12 628) with mean diameter of iAAA repair (r2 = 0.2, p = .1). CONCLUSION: Despite recommendations from learned society guidelines, data indicate variations in mean diameter for AAA repair. There was no significant correlation between mean diameter of AAA repair and rates of iAAA repair and rAAA repair. These analyses are subject to differences in disease prevalence, uncertainties in rupture rates, validations of vascular registries, causes of death and registrations.

Association of Operative Repair Type and Trauma Center Designation With Outcomes in Ruptured Abdominal Aortic Aneurysm Repair.

OBJECTIVE: Open repair of ruptured abdominal aortic aneurysm (rAAA) has shown improved outcomes at trauma centers. Whether the benefit of trauma center designation extends to endovascular repair of rAAA is unknown. METHODS: Retrospective cohort study using the California Office of Statewide Health Planning and Development 2007 to 2014 discharge database to identify patients with rAAA. Data included demographic and admission factors, discharge disposition, International Classification of Diseases, Ninth Revision, Clinical Modification codes, and hospital characteristics. Hospitals were categorized by trauma center designation and teaching hospital status. The effect of repair type and trauma center designation (level I, level II, or other-other trauma centers and nondesignated hospitals) was evaluated to determine rates and risks of 9 postoperative complications, in-hospital mortality, and 30-day postdischarge mortality. RESULTS: Of 1941 rAAA repair patients, 61.2% had open and 37.8% had endovascular; 1.0% had both. Endovascular repair increased over the study interval. Hospitals were 12.0% level I, 25.0% level II, and 63.0% other. A total of 48.7% of hospitals were teaching hospitals (level I, 100%; level II, 42.2%; and other, 41.8%). Endovascular repair was significantly more common at teaching hospitals (41.5% vs 34.3%, P < .001) and was the primary repair method at level I trauma centers (P < .001). Compared with open repair, endovascular repair was protective for most complications and in-hospital mortality. The risk for in-hospital mortality was highest among endovascular patients at level II trauma centers (hazard ratio 1.67, 95% confidence interval [CI]: 0.95-2.92) and other hospitals (hazard ratio 1.66, 95% CI: 1.01-2.72). CONCLUSIONS: Endovascular repair overall was associated with a lower risk of adverse outcomes. Endovascular repair at level I trauma centers had a lower risk of in-hospital mortality which may be a result of their teaching hospital status, organizational structure, and other factors. The weight of the contributions of such factors warrants further study.

Sex differences in Japanese patients with ruptured aortic aneurysms.

OBJECTIVE: This study aimed to assess the sex differences in clinical presentation and outcomes of Japanese patients with ruptured aortic aneurysm (rAA) using a large nationwide claims-based database in Japan. METHODS: We identified patients hospitalized in certified teaching hospitals in Japan with rAA between April 1, 2012, and March 31, 2015. Patients' characteristics and in-hospital outcomes were compared between men and women. The Barthel index was used for evaluating functional status at discharge by examining the ability to perform basic daily activities. RESULTS: Of 7086 eligible patients, 32.3% (2291/7086) were women. Women were older than men (81.9 years vs 76.1 years; P < .001), had higher prevalence of coma at admission (33.2% vs 25.2%; P < .001), and were less likely to undergo emergency operation including endovascular aneurysm repair (35.7% vs 51.1%; P < .001). The unadjusted mortality rate (62.5% vs 52.0%; P < .001) and Barthel index at discharge (78.7 vs 86.1; P < .001) were significantly worse in women than in men. However, multilevel mixed-effect logistic regression analyses showed that female sex itself was not an independent predictor for in-hospital death (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.78-1.04; P = .17). Older age, coma at admission, and vasopressor use were detected as independent predictors for in-hospital death. The same results were confirmed for each rupture site. Stratified analyses showed that older women (threshold, 80 years; OR, 0.81; 95% CI, 0.66-0.98; P = .028) and those who underwent emergency operation (OR, 0.75; 95% CI, 0.61-0.93; P = .009) showed significantly better outcomes than men. CONCLUSIONS: In a univariate analysis, female patients with rAA showed worse mortality than men because of their older age, more severe clinical presentation, and low emergency operation rate. However, after adjustment for covariates, female sex itself was not associated with increased mortality.

Editor's Choice - Endovascular Repair Versus Surgical Repair for Japanese Patients With Ruptured Thoracic and Abdominal Aortic Aneurysms: A Nationwide Study.

OBJECTIVE: This study compared outcomes after endovascular aneurysm repair (ER) and open surgical repair (OR) of ruptured descending thoracic aortic aneurysms (rDTAA) and ruptured abdominal aortic aneurysms (rAAA) through a nationwide analysis performed in Japan. METHODS: This was a national registry based retrospective comparative study using data from the Japanese Registry of all Cardiac and Vascular Diseases Diagnostic Procedure Combination (JROAD-DPC) database, a nationwide claim based database from more than 600 hospitals. Patients admitted to certificated teaching hospitals with rDTAA and rAAA and treated by either ER or OR between 1 April 2012 and 31 March 2015 were identified. A propensity score matched analysis was performed to compare ER and OR. RESULTS: About 40% of the total cohort (n = 8,302) were managed conservatively for various reasons, including limited options in primary care facilities in certain areas. In total, 983 patients had rDTAA (OR = 511; ER = 472) and 2,320 (OR = 1,754; ER = 566) had rAAA. Altogether, 604 and 1,080 patients were matched with rDTAA and rAAA, respectively. Compared with OR, ER was associated with significantly better in hospital mortality in patients with rDTAA (ER = 22.5%; OR = 29.8% [p < .001]) and similar mortality for those with rAAA (ER = 25.7%; OR = 24.3% [p = .57]). ER involved significantly shorter hospital stays for rDTAA (ER = 25.5; OR = 32 days [p < .001]) and rAAA (ER = 16; OR = 21 days [p < .001]). The median Barthel Index at discharge was ≥75/100 for all groups, and there were no differences between ER and OR. Total medical costs were significantly lower for ER for rDTAA (ER = ¥6.47 million, OR = ¥7.28 million [p < .001]) but were higher for rAAA (ER = ¥4.65 million; OR = ¥3.43 million [p < .001]). CONCLUSION: A Japanese nationwide observational study showed that in hospital outcomes for ER vs. OR were more favourable for rDTAA and comparable for rAAA. ER resulted in an equivalently favourable functional status at discharge and significantly shorter hospital stays.

Q-TWiST and Cost-Effectiveness Analysis of Endovascular versus Open Repair for Ruptured Abdominal Aortic Aneurysms in a High Deliberate Practice Volume Center.

BACKGROUND: The objective of the study was to compare the cost-effectiveness of endovascular aortic repair (rEVAR) versus open surgical repair (rOSR) for ruptured abdominal aortic aneurysm (rAAA), where rEVAR is regularly performed outside of instructions for use (IFUs) (shorter and more angulated necks). Primary end point is incremental cost-effectiveness ratio (ICER) of rEVAR versus rOSR and aneurysm-related mortality. Secondary end points are cost per quality-adjusted life years (QALYs), perioperative morbidity and mortality, reintervention, and all-cause mortality. METHODS: All rAAA repairs performed between 2002 and 2016 in a single center were scrutinized. Between 2002 and 2007, most rAAAs were repaired using rOSR. From 2007 to 2016, we implemented a rEVAR with an anatomically possible protocol. During this time, severe angulation was rarely seen as a contraindication to rEVAR, and rEVAR was performed on aneurysms with an infrarenal aortic neck cranial to the aneurysm with a diameter of 20-33 mm and a length of at least 5 mm. Demographics and outcomes were reported according to the Society for Vascular Surgery guidelines. QALY was measured based on quality of time spent without symptoms of disease or toxicity of treatment (Q-TWiST) assessment. RESULTS: Eight hundred aneurysm surgeries were performed; of these, 135 were emergency surgeries of which 88 were for rAAA; (42 rEVARs and 46 rOSRs). Primary technical success (rEVAR 89.1% vs. rOSR 87.8%; P = 0.1), perioperative morbidity (rEVAR 56.5% vs. rOSR 64.3%; P = 0.457), and mortality (rEVAR 26.1% vs. rOSR 28.6%; P = 0.794) were nonsignificantly favorable in rEVAR patients. Freedom from reintervention was significantly lower in rEVAR patients at 3 years (rEVAR 74% vs. rOSR 90%; P = 0.038). Three-year aneurysm-related survival (rEVAR 65% vs. rOSR 62%; P = 0.848) and all-cause survival (rEVAR 56% vs. rOSR 51%; P = 0.577) were higher in rEVAR patients. At 3 years, rEVAR patients had a higher QALY of 1.671 versus OSR of 1.549 (P = 0.502). Operating room (P = 0.001) and total accommodation costs (P = 0.139) were lower in rEVAR patients, while equipment (P < 0.001), surveillance, and reintervention (P < 0.001) costs were higher. Median cost of rEVAR at 3 years was €23,352 vs. €20,494 for OSR (P < 0.084) (power>80%). Median cost per QALY of rEVAR at 3 years was €13,974 vs. €13,230 for rOSR (P = 0.296). ICER for rEVAR versus rOSR was €23,426 (95% confidence interval [CI] < €0 to > €30,000). At 3 years, the area under the curve and 95% CI for Q-TWiST was higher in rEVAR compared with OSR (rEVAR 500.819 vs. rOSR 437.838). CONCLUSIONS: There is no significant difference in cost or QALYs between rEVAR and rOSR even when rEVAR is performed on complex cases outside of IFU (shorter and more angulated necks). There is a significantly higher freedom from secondary intervention in rOSR patients compared with rEVAR patients at 3 years.

A Decade of Thoracic Endovascular Aortic Aneurysm Repair in New York State: Volumes, Outcomes, and Implications for the Dissemination of Endovascular Technology.

BACKGROUND: The purpose of this study was to characterize utilization and outcomes of thoracic endovascular aortic aneurysm repair (TEVAR) in New York State during the first decade of commercial availability, with respect to evolving indications, results, and costs. Of specific interest was evaluation of the volume-outcome relationship for this relatively uncommon procedure. METHODS: The New York Statewide Planning and Research Cooperative System database was queried to identify patients undergoing TEVAR from 2005 to 2014 for aortic dissection (AD), non-ruptured aneurysm (NRA), and ruptured aneurysm (RA). Outcomes assessed included in-hospital mortality, complications, and costs. Linkage to the National Provider Identifier and New York Office of Professions databases facilitated comparisons by surgeon and facility volume. RESULTS: One thousand eight hundred thirty-eight patients were identified: 334 AD, 226 RA, and 1,278 NRA. Since introduction, TEVAR implantation increased significantly over the 10-year period in all groups (P < 0.01), with recent increase in utilization for AD. Increased in-hospital mortality correlated with RA (OR 5.52 [3.02-10.08], P < 0.01), coagulopathy (3.38 [2.02-5.66], P < 0.01), cerebrovascular disease (2.47 [1.17-5.22], P = 0.02), and nonwhite/nonblack race (1.74 [1.08-2.82], P = 0.02). Early in the experience (2005-2007), patients were more likely to be treated at high-volume facilities (>17 per year) and by high-volume surgeons (>5 per year), (P < 0.01). Since 2011, however, most patients (53%) have undergone TEVAR by low-volume surgeons (<3 per year). Neither surgeon nor hospital volume was associated with clinical outcomes. CONCLUSIONS: Since the introduction of TEVAR, comparable results have been obtained across hospital and surgeon volume strata. Favorable outcomes, even in low-volume settings, underscore the complexity of volume-outcome relationships in high-acuity procedures. These findings have implications for credentialing, regionalization, and future dissemination of advanced endovascular technology.

Editor's Choice - Metformin Prescription is Associated with a Reduction in the Combined Incidence of Surgical Repair and Rupture Related Mortality in Patients with Abdominal Aortic Aneurysm.

OBJECTIVES: Currently there is no drug therapy for abdominal aortic aneurysm (AAA) and most previous investigations have focused on imaging rather than clinical outcomes. The aim of this study was to assess whether AAA related clinical events were lower in patients prescribed metformin. METHODS: This was a prospective cohort observational study performed in three cities in Australia, which was designed to study risk factors for clinical events not simply to focus on metformin. Patients with an asymptomatic unrepaired AAA of any diameter ≥30 mm were recruited from hospital outpatient clinics and surveillance programs run at four centres. The main outcome was the requirement for AAA repair or AAA related mortality (AAA events). The association between metformin prescription and AAA events was assessed using Kaplan-Meier analysis and Cox proportional hazard analysis. RESULTS: Patients (1,080) with a mean (SD) initial AAA diameter of 46.1 (11.3) mm were followed for a mean (SD) of 2.5 (3.1) years until an AAA event (n = 454), death (n = 176), loss to follow up (n = 128), or completion of current follow up (n = 322). Patients with diabetes who were prescribed metformin (adjusted HR 0.63, 95% CI 0.44-0.93), but not patients with diabetes who were not prescribed metformin (adjusted HR 1.15, 95% CI 0.83-1.59), had a lower incidence of AAA events compared with those without diabetes. Findings were similar in sensitivity analyses restricted to patients with an initial AAA diameter ≤50 mm and patients with a minimum follow up of six months before an AAA event. CONCLUSIONS: These findings suggest that clinically important AAA events may be reduced in patients with diabetes who are prescribed metformin, but not those with diabetes receiving other treatments. A randomised controlled trial is needed to definitively test whether metformin reduces AAA related clinical events in patients with small AAAs who do not have diabetes.

Increasing Incidence of Thoracic Aortic Aneurysm Repair in Germany in the Endovascular Era: Secondary Data Analysis of the Nationwide German DRG Microdata.

OBJECTIVES: Nationwide population based data on epidemiology and surgical treatment of descending thoracic aortic (DTA) aneurysms are not available for Germany. The aim was to assess the in hospital incidence, and to report outcomes of patients who received surgical treatment. METHODS: Data were acquired by analysing the diagnosis related group (DRG) statistics of the German Federal Statistical Office. All inpatient cases of ruptured (rDTA aneurysm, ICD Code I71.1) or non-ruptured DTA aneurysm (nrDTA aneurysm; I71.2) who received thoracic endovascular (TEVAR; OPS procedure code 5-38a.7/70/8/80) or open aortic repair (OAR; OPS 5-384.3) between 2005 and 2014 were included. To adjust for sex, age, medical risk (Elixhauser comorbidity score), type of procedure, and type of admission, a multilevel multivariable regression model with robust error variance was applied. The primary outcome was in hospital mortality; secondary outcomes were organ complications. A volume outcome analysis was performed. RESULTS: A total of 48,098 cases of DTA aneurysm (5,848, 12.2% rDTA aneurysm) were identified. The average age was 69 ± 12 years. 65.2% were male. Frequent comorbidities were hypertension (74.9%), peripheral artery disease (including abdominal aortic aneurysm, 42.6%), other heart diseases (41.6%), coronary heart disease (26.2%), and renal failure (22.5%). Surgical treatment was received by 4969 patients (10.3%): 4057 TEVAR (81.6%) and 912 OAR (18.4%) procedures. Mortality for rDTA aneurysm was 42.9% (OAR) and 22.3% (TEVAR). It was 10.5% and 3.7% for DTA aneurysm, respectively. Rupture, increasing age, and higher comorbidity score were significantly associated with higher mortality (RR 6.66, 5.33-8.25; 1.28, 1.17-1.40; and 1.06, 1.05-1.08, respectively). Endovascular treatment was associated with lower mortality (RR 0.31, 0.23-0.41). Hospital volume was not significantly associated with in hospital mortality. CONCLUSIONS: Eighty per cent of patients treated surgically for a DTA aneurysm receive endovascular therapy, with low peri-operative mortality in non-ruptured cases. Elective endovascular repair should be considered for individuals at a high risk of rupture who are fit for surgery. Open repair, increased age, and a high comorbidity score are associated with higher mortality.

Contrast Enhanced Three Dimensional Ultrasound for Intraluminal Thrombus Assessment in Abdominal Aortic Aneurysms.

OBJECTIVES: The impact of intraluminal thrombus (ILT) on abdominal aortic aneurysm (AAA) progression can be investigated non-invasively by three dimensional contrast enhanced ultrasound (3D-CEUS). The aim was to validate 3D-CEUS ILT volume and thickness measurements against computed tomography angiography (CTA), and to determine inter- and intra-operator reproducibility. METHODS: The design was for a planned comparison of 3D-CEUS and CTA and of repeated 3D-CEUS measurements in a blinded set up. Consecutive patients with asymptomatic AAA (n = 137, maximum diameter 30-55 mm) from a single centre were consecutively assessed by CTA and 3D-CEUS in a blinded setup. After exclusion of failed CTA (n = 2) and inconclusive 3D-CEUS (n = 8), 127 3D-CEUS/CTA pairs were analysed by Bland-Altman plots. 3D-CEUS inter- and intra-operator reproducibility were determined in a subgroup (n = 30) measured twice by two blinded investigators. RESULTS: In 24 of 127 (19%) patients, no ILT was found on 3D-CEUS. Intraluminal thrombus absence was confirmed by 3D-CTA analysis in all but two cases. Mean ILT volume difference between 3D-CEUS and CTA was 2.2 mL (5% of mean volume) and range of variability (ROV) amounted to ± 10.2 mL. Mean ILT thickness difference was 0.6 mm with a ROV of ± 4.6 mm 3D-CEUS inter-operator variations of ILT volume and thickness measurements were low (ROV ± 8.8 mL and ±2.9 mm, respectively). The corresponding intra-operator ROVs were ±7.5 mL and ±3.3 mm, respectively. CONCLUSIONS: 3D-CEUS demonstrated good reproducibility and a good agreement with CTA when estimating ILT volume and maximum thickness in AAA patients. It is a promising research tool to investigate potential interactions between ILT, AAA growth, and rupture.