Trends in aortic dissection hospitalizations, interventions, and outcomes among medicare beneficiaries in the United States, 2000-2011

Navigating clinical appropriateness: A review of management strategies for type B aortic dissection

Aortic dissection is a catastrophic, life-threatening event. Its management depends on the anatomic location of the intimal tear (type A v B) and the clinical presentation in type B aortic dissection. In this article, the current evidence supporting clinical practice, gaps in knowledge, and the need for more rigorous research and higher-quality studies are reviewed.

Delamination Strength and Elastin Interlaminar Fibers Decrease with the Development of Aortic Dissection in Model Rats

Aortic dissection (AD) is a life-threatening tear of the vascular tissue with creation of a false lumen. To explore the mechanism underlying this tissue tear, this study investigated the delamination strength of AD model rats and the histological composition of the aorta at various stages of AD development. SD rats were administrated beta-amino propionitrile for 0 (Control), 3 (Pre-dissection), and 6 (Dissection) weeks. The thoracic aorta was harvested at 10-11 weeks of age. The Dissection group exclusively showed AD at the ascending aorta. The delamination strength, a force that separates the aorta in the radial direction, of the descending aorta decreased significantly in the order of the Control, Pre-dissection, and Dissection groups. A quantitative histological analysis of the aortic tissue demonstrated that, compared with the Control group, the area fraction of collagen was significantly higher in the Pre-dissection and Dissection groups and that of elastin was significantly lower in the Dissection group. The area fraction of the elastin fibers between the elastic laminas (interlaminar fibers) was significantly decreased in the order of the Control, Pre-dissection, and Dissection groups. Histological changes of the aortic tissue, perhaps a reduction in interlaminar fibers mainly aligned in the radial direction, decreased delamination strength, thereby causing AD.

Angiogenesis inhibitor-specific hypertension increases the risk of developing aortic dissection

Aortic dissection is an adverse event of angiogenesis inhibitors; however, the association between the drugs and aortic dissection is unclear. Therefore, we investigated if and how angiogenesis inhibitors increase the onset of aortic dissection using pharmacologically-induced aortic dissection-prone model (LAB) mice, cultured endothelial cells, and real-world databases, which is a novel integrated research approach. Disproportionality analysis was performed and calculated using the reporting odds ratio as a risk signal using a worldwide database of spontaneous adverse events to estimate the risk of adverse events. Angiogenesis inhibitors, but not other hypertension-inducing drugs, showed significant risk signals for aortic aneurysms and dissection. A retrospective cohort analysis using JMDC, a medical receipt database in Japan, showed that the history of atherosclerosis and dyslipidemia, but not hypertension, were significantly associated with the onset of aortic dissection during angiogenesis inhibitor medication administration. For in vivo studies, sunitinib (100 mg/kg/day) was administered to LAB mice. Sunitinib increased systolic blood pressure (182 mmHg vs. 288 mmHg with sunitinib; p＜0.01) and the incidence of aortic dissection (40% vs. 59% with sunitinib; p = 0.34) in mice. In vivo and in vitro studies revealed that sunitinib increased endothelin-1 expression and induced endothelial cell damage evaluated by intracellular- and vascular cell adhesion molecule-1 expressions. The increased risk of developing aortic dissection with angiogenesis inhibitors is associated with the development of drug-specific hypertension via endothelial cell damage and endothelin-1 expression. Our findings are invaluable in establishing safer anticancer therapies and strategies to prevent the development of vascular toxicity in high-risk patients.

Acute aortic syndrome: nationwide study of epidemiology, management, and outcomes

BACKGROUND

Epidemiological studies on acute aortic syndrome (AAS) have relied largely on unverified administrative coding, leading to wide-ranging estimates of incidence. This study aimed to evaluate the incidence, management, and outcomes of AAS in Aotearoa New Zealand.

METHODS

This was a national population-based retrospective study of patients presenting with an index admission of AAS from 2010 to 2020. Cases from the Ministry of Health National Minimum Dataset, National Mortality Collection, and the Australasian Vascular Audit were cross-verified with hospital notes. Poisson regression adjusted for sex and age was used to investigate trends over time.

RESULTS

During the study interval, 1295 patients presented to hospital with confirmed AAS, including 790 with type A (61.0 per cent) and 505 with type B (39.0 per cent) AAS. A total of 290 patients died out of hospital between 2010 and 2018. The overall incidence of aortic dissection including out-of-hospital cases was 3.13 (95 per cent c.i. 2.96 to 3.30) per 100 000 person-years, and this increased by an average of 3 (95 per cent c.i. 1 to 6) per cent per year after adjustment for age and sex adjustment on Poisson regression, driven by increasing type A cases. Age-standardized rates of disease were higher in men, and in Māori and Pacific populations. The management strategies used, and 30-day mortality rates among patients with type A (31.9 per cent) and B (9.7 per cent) disease have remained constant over time.

CONCLUSION

Mortality after AAS remains high despite advances over the past decade. The disease incidence and burden are likely to continue to increase with an ageing population. There is impetus now for further work on disease prevention and the reduction of ethnic disparities.

Increased aortic repair in Germany correlates with reduction of death caused by aortic aneurysms but not aortic dissections

INTRODUCTION

We asked if there is a significant correlation between the increasing trend in aortic repair (AR) and decreasing aortic aneurysm (AA) and aortic dissection (AD) mortality? Therefore, we retrospectively analyzed all aortic repairs in patients with AA and AD and its correlation with disease-specific death rates and hospitalizations for ruptured AA and AD in Germany.

METHODS

We retrieved the number of cases hospitalized for AA and AD as well as the procedures in these cases from the Federal Bureau of Statistics (DRG statistics) and death rates from the national mortality statistic published by the Federal Statistical Office in Germany for the years 2006-2017.

RESULTS

From 2006 to 2017, the total number of hospitalized cases admitted with principal diagnosis of AA increased by 25.8% and that of AD by 56.7%. That of cases with the principal diagnosis of ruptured AA (rAA) remained unchanged (-2.5%) and that with rAD increased by 54.6%. The number of (open and endovascular) procedures in cases hospitalized for AA increased by 39.4% and for AD by 126.4%. The age-adjusted death rates in Germany for AA decreased from 4.0 to 2.9 per 100,000 inhabitants and that for AD increased from 1.0 to 1.4. The decrease in death attributed to AA cases can be described by linear regression as y = -0.0003*y + 6.7076 (p < 0.0001). Accepting this association between increased elective procedures and reduced AA mortality, each/all 1000 procedures save 0.3 lives per 100,000 inhabitants.

CONCLUSION

Despite increasing numbers of AR for AA and AD, only the mortality rate for all AAs decreased, while we did not observe a decrease in overall mortality of AD in Germany.

Initial Thoracic Endovascular Aortic Repair vs Medical Therapy for Acute Uncomplicated Type B Aortic Dissection

Importance

Thoracic endovascular aortic repair (TEVAR) has increasingly been used for uncomplicated type B aortic dissection (uTBAD) despite limited supporting data.

Objective

To assess whether initial TEVAR following uTBAD is associated with reduced mortality or morbidity compared with medical therapy alone.

Design, Setting, and Participants

This cohort study included Centers for Medicare & Medicaid Services inpatient claims data for adults aged 65 years or older with index admissions for acute uTBAD from January 1, 2011, to December 31, 2018, with follow-up available through December 31, 2019.

Exposures

Initial TEVAR was defined as TEVAR within 30 days of admission for acute uTBAD.

Main Outcomes and Measures

Outcomes included all-cause mortality, cardiovascular hospitalizations, aorta-related and repeated aorta-related hospitalizations, and aortic interventions associated with initial TEVAR vs medical therapy. Propensity score inverse probability weighting was used.

Results

Of 7105 patients with eligible index admissions for acute uTBAD, 1140 (16.0%) underwent initial TEVAR (623 [54.6%] female; median age, 74 years [IQR, 68-80 years]) and 5965 (84.0%) did not undergo TEVAR (3344 [56.1%] female; median age, 76 years [IQR, 69-83 years]). Receipt of TEVAR was associated with region (vs South; Midwest: adjusted odds ratio [aOR], 0.66 [95% CI, 0.53-0.81]; P < .001; Northeast: aOR, 0.63 [95% CI, 0.50-0.79]; P < .001), Medicaid dual eligibility (aOR, 0.76; 95% CI, 0.63-0.91; P = .003), hypertension (aOR, 1.26; 95% CI, 1.03-1.54; P = .03), peripheral vascular disease (aOR, 1.24; 95% CI, 1.02-1.49; P = .03), and year of admission (2012, 2013, 2014, and 2015 were associated with greater odds of TEVAR compared with 2011). After inverse probability weighting, mortality was similar for the 2 strategies up to 5 years (hazard ratio [HR], 0.95; 95% CI, 0.85-1.06), as were aorta-related hospitalizations (HR, 1.12; 95% CI, 0.99-1.27), aortic interventions (HR, 1.01; 95% CI, 0.84-1.20), and cardiovascular hospitalizations (HR, 1.05; 95% CI, 0.93-1.20). In a sensitivity analysis that included deaths within the first 30 days, initial TEVAR was associated with lower mortality over a period of 1 year (adjusted HR [aHR], 0.86; 95% CI, 0.75-0.99; P = .03), 2 years (aHR, 0.85; 95% CI, 0.75-0.96; P = .008), and 5 years (aHR, 0.87; 95% CI, 0.80-0.96; P = .004).

Conclusions and Relevance

In this study, 16.0% of patients underwent initial TEVAR within 30 days of uTBAD, and receipt of initial TEVAR was associated with hypertension, peripheral vascular disease, region, Medicaid dual eligibility, and year of admission. Initial TEVAR was not associated with improved mortality or reduced hospitalizations or aortic interventions over a period of 5 years, but in a sensitivity analysis that included deaths within the first 30 days, initial TEVAR was associated with lower mortality. These findings, along with cost-effectiveness and quality of life, should be assessed in a prospective trial in the US population.

Sex Differences in Trends in Incidence of Thoracic Aortic Aneurysm Repair and Aortic Dissection: 2005-2015

Background

The purpose of this study was to examine trends in the incidence of thoracic aortic aneurysm (TAA) repair and aortic dissection.

Methods

A retrospective study was conducted of patients from the period 2005-2015 with thoracic aortic disease. Unadjusted mortality was compared in women vs men. Rates of scheduled TAA repair, dissection events, acute type A aortic dissection (TAAD) repair, and aorta-related mortality were obtained from our institution's clinical registry and administrative data sources and used to calculate the age-adjusted incidence for each sex, adjusted to the Canadian standard population. Weighted linear regression was performed to analyze trends over time.

Results

A total of 382 scheduled TAA repair operations, 345 dissection events, 85 TAAD repairs, and 182 aorta-related mortalities were identified. Women accounted for 23% of TAA repairs, 39% of dissection events, 22% of TAAD repairs, and 45% of aorta-related mortalities. The incidence of TAA repair was 3.5 per 100,000 person-years (95% confidence interval [CI]: 3.2-3.9), and increased in men (P = 0.02) but not women (P = 0.10) over time. The incidence of aortic dissection was 3.4 per 100,000 (95% CI: 3.1-3.8) and was stable over time (P = 0.43). The average annual age-adjusted incidence of TAAD repair was 0.8 per 100,000 (95% CI: 0.6-1.0) and increased over time (P = 0.001). The overall incidence of aorta-related mortality was 1.8 per 100,000 (95% CI: 1.5-2.0) and decreased over time (P = 0.02).

Conclusion

The incidence of TAA repair is increasing in men but not women. Although aorta-related mortality is decreasing overall, disparities exist between the male and female population.

Contemporary Unplanned Readmission Trends Following Management of Type B Aortic Dissection

Purpose

Methods

Results

Conclusion

Demographic and Regional Trends of Mortality in Patients With Aortic Dissection in the United States, 1999 to 2019

Background

Aortic dissection (AoD) is associated with high morbidity and mortality. However, the burden of AoD mortality is not well characterized, and contemporary data and mortality trends in different demographic and geographic subgroups have not been described.

Methods and Results

Trends in AoD mortality were assessed using a cross‐sectional analysis of the Centers for Disease Control and Prevention Wide‐Ranging Online Data for Epidemiologic Research database. Crude and age‐adjusted mortality rates (AAMR) per 1 million people with associated annual percent changes were determined. Joinpoint regression was used to assess trends in the overall sample and different demographic (sex, race and ethnicity, age) and geographic subgroups. Between 1999 and 2019, a total of 86 855 AoD deaths occurred within the United States. In the overall population, AAMR was 21.1 per 1 million in 1999 and 21.3 in 2019. After an initial decline in mortality, AAMR increased from 2012 to 2019, with an associated annual change of 2.5% (95% CI, 1.8–3.3). Men, older adults (aged ≥85 years), and non‐Hispanic Black or African American individuals had higher mortality rates than women, younger individuals, and other racial and ethnic individuals, respectively. Despite lower AAMRs throughout the study period, women experienced greater increases in AAMR from 2012 to 2019 compared with men. Similarly, non‐Hispanic Black or African American individuals had a pronounced increase in AAMR from 2012 to 2019.

Conclusions

Despite an initial decline in AoD mortality, the mortality rate has been increasing from 2012 to 2019, with pronounced increases among women and non‐Hispanic Black or African American individuals.

Differences in Mid-Term Outcomes Between Patients Undergoing Thoracic Endovascular Aortic Repair for Aneurysm or Acute Aortic Syndromes: Report From the Global Registry for Endovascular Aortic Treatment

PURPOSE

To analyze differences in baseline characteristics, overall mortality, device-related mortality, and re-intervention rates in patients who underwent thoracic endovascular aortic repair (TEVAR) for descending thoracic aortic aneurysm (DTAA) with atherosclerotic/degenerative cause or acute aortic syndrome (AAS), using the Global Registry For Endovascular Aortic Treatment (GREAT).

MATERIALS AND METHODS

Patients submitted to TEVAR for AAS or DTAA, included in GREAT, were eligible for this analysis. Primary outcome was 30-day all-cause mortality rate. Secondary outcomes were 30-day aorta-related mortality and re-intervention rate, 1-year and 3-year all-cause mortality, aorta-related mortality and re-intervention rate.

RESULTS

Five-hundred and seventy-five patients were analyzed (305 DTAA and 270 AAS). Thirty-day mortality rate was 1.3% and 1.8% for DTAA and AAS, respectively (p=0.741). One-year and 3-year mortality rates were 6.2% versus 9.3 and 17.3% versus 15.9% for DTAA and AAS, respectively (p=0.209 and p=0.655, respectively). Aorta-related mortality rates at 30 days, 1 year and 3 years were 1.3%, 1.3%, and 2.6% for DTAA, 1.8%, 4.2%, and 4.2% for AAS (p=ns). Re-intervention rates at 30 days, 1 year, and 3 years were 1.3%, 4.3%, and 7.5% for DTAA, 3.3%, 8.1%, and 10.7% for AAS (p=ns). Furthermore, a specific analysis with similar outcomes was performed dividing follow-up in 3 periods (1-30 days, 31-365 days, 366-1096 days) and describing mutual differences between 2 groups and temporal trends in each group.

CONCLUSION

Patients who underwent TEVAR for DTAA or AAS experienced different mortality and re-intervention rates among years during mid-term follow-up. Although all-cause related deaths within 30 days were TEVAR-related, aorta-related deaths were more common for AAS patients within 1 year. A greater re-intervention rate was described for AAS patients, although only 1 year after TEVAR.

Low ambient temperature and temperature drop between neighbouring days and acute aortic dissection: a case-crossover study

AIMS

The incidence of acute aortic dissection (AAD) has been shown to have seasonal variation, but whether this variation can be explained by non-optimum ambient temperature and temperature change between neighbouring days (TCN) is not clear.

METHODS AND RESULTS

We performed a time-stratified case-crossover study in the Registry of Aortic Dissection in China covering 14 tertiary hospitals in 11 cities from 2009 to 2019. A total of 8182 cases of AAD were included. Weather data at residential address were matched from nearby monitoring stations. Conditional logistic regression model and distributed lag nonlinear model were used to estimate the associations of daily temperature and TCN with AAD, adjusting for possible confounders. We observed an increase of AAD risk with lower temperature cumulated over lag 0-1 day and this association became statistically significant when daily mean temperature was below 24°C. Relative to the referent temperature (28°C), the odds ratios (ORs) of AAD onset at extremely low (-10°C) and low (1°C) temperature cumulated over lag 0-1 day were 2.84 [95% confidence interval (CI): 1.69, 4.75] and 2.36 (95% CI: 1.61, 3.47), respectively. A negative TCN was associated with increased risk of AAD. The OR of AAD cumulated over lag 0-6 days was 2.66 (95% CI: 1.76, 4.02) comparing the extremely negative TCN (-7°C) to no temperature change. In contrast, a positive TCN was associated with reduced AAD risk.

CONCLUSION

This study provides novel and robust evidence that low ambient temperature and temperature drop between neighbouring days were associated with increased risk of AAD onset.

KEY QUESTION

Incidence of acute aortic dissection (AAD) was reported to have seasonal trends, but it remains unclear whether non-optimum ambient temperature and temperature change between neighbouring days (TCN) is associated with AAD onset.

KEY FINDING

Daily mean temperature lower than 24°C was significantly associated with increased risk of AAD at lag 0-1 day. A negative TCN (temperature drop) was associated with increased risk of AAD, whereas a positive TCN was associated with decreased risk.

TAKE HOME MESSAGE

This multi-centre, case-crossover study provides novel and robust evidence that low ambient temperature and temperature drop between neighbouring days were associated with increased AAD risk.

Development and Validation of a Predictive Model to Identify Patients With an Ascending Thoracic Aortic Aneurysm

Background

Screening protocols do not exist for ascending thoracic aortic aneurysms (ATAAs). A risk prediction algorithm may aid targeted screening of patients with an undiagnosed ATAA to prevent aortic dissection. We aimed to develop and validate a risk model to identify those at increased risk of having an ATAA, based on readily available clinical information.

Methods and Results

This is a cross‐sectional study of computed tomography scans involving the chest at a tertiary care center on unique patients aged 50 to 85 years between 2013 and 2016. These criteria yielded 21 325 computed tomography scans. The double‐oblique technique was used to measure the ascending thoracic aorta, and an ATAA was defined as >40 mm in diameter. A logistic regression model was fitted for the risk of ATAA, with readily available demographics and comorbidity variables. Model performance was characterized by discrimination and calibration metrics via split‐sample testing. Among the 21 325 patients, there were 560 (2.6%) patients with an ATAA. The multivariable model demonstrated that older age, higher body surface area, history of arrhythmia, aortic valve disease, hypertension, and family history of aortic aneurysm were associated with increased risk of an ATAA, whereas female sex and diabetes were associated with a lower risk of an ATAA. The C statistic of the model was 0.723±0.016. The regression coefficients were transformed to scores that allow for point‐of‐care calculation of patients' risk.

Conclusions

We developed and internally validated a model to predict patients' risk of having an ATAA based on demographic and clinical characteristics. This algorithm may guide the targeted screening of an undiagnosed ATAA.

A Systematic Review and Meta-analysis of the Incidence of Acute Aortic Dissections in Population-Based Studies

OBJECTIVE

To perform a systematic-review and meta-analysis of all population-based studies reporting on incidence of acute aortic dissections.

METHODS

We searched MEDLINE, EMBASE, CENTRAL and Open Grey databases from inception to August 2020 for population-based studies reporting on the incidence of AAD. A systematic review was conducted following the PRISMA guidelines using a registered protocol (CRD42020204007). Data was pooled using a random-effects model of proportions using Freeman-Tukey double arcsine transformation. The main outcome was the incidence of AAD. Secondary outcomes were incidence type A aortic dissections (TAAD) and type B aortic dissections (TBAD); incidence of aortic dissection repair and medical management and incidence of in-hospital mortality. In addition, we estimated the proportion of aortic dissection repair and mortality (in hospital, overall and specific mortality according to sub-type) among patients with AAD.

RESULTS

Thirty-three studies were included. The pooled incidence of AADs was 4.8 per 100 000 individuals/year (95%CI: 3.6; 6.1). Incidence of TAAD was 3.0 per 100 000/year (95%CI: 1.8; 4.4) and incidence of TBAD was 1.6 per 100 000/year (95%CI: 1.1; 2.2). The incidence of AAD needing repair was 1.4 per 100 000/year (95%CI: 1.0; 2.0) [1.4 (95%CI: 1.2; 1.7) for TAAD and 0.4 (95%CI: 0.2; 0.7) for TBAD]. Incidence of medically managed AAD was 3.4 per 100 000/year (95%CI: 2.4; 4.5). Incidence of in-hospital death due to AAD was 1.3 per 100 000 individuals/year (95%CI: 0.9; 1.9); 1.0 (95%CI: 0.6; 1.4; I²97%) for TAAD and 0.3 for TBAD (95%CI: 0.2; 0.4; I²96%).

CONCLUSION

A global estimate regarding the incidence rate of acute aortic dissections was achieved. Incidence of acute aortic dissection varied significantly between study designs and geographical regions. More accurate information on acute aortic dissection epidemiology is crucial for public-health decisions, clinical understanding, and healthcare management.

Ninety-Day Readmission After Open Surgical Repair of Stanford Type A Aortic Dissection

BACKGROUND

Investigations into readmissions after surgical repair of acute Stanford Type A aortic dissection (TAAD) remain scarce. We analyzed potential risk factors for readmission after TAAD.

METHODS

The 2013-2014 United States Nationwide Readmissions Database was queried for TAAD index hospitalizations and 90-day readmissions indicated by diagnostic and procedural codes. Multivariable analysis was completed to identify risk factors and the most common reasons for readmission.

RESULTS

We identified 6,975 patients (65% male; age, 60.0±0.4 years) who underwent surgical repair for TAAD. Overall, 2,062 patients (29.6%) were readmitted within 90 days: 634 (30.7%) during the first 30 days, and 1,428 (69.3%) during days 31-90. Readmitted patients had a higher prevalence of chronic kidney disease at index admission (18.0% vs 11.6%, P=.002), greater overall index length of stay (17.8±0.6 vs 15.5±0.4 days; P=.0003), and greater index hospitalization cost ($90,637±$2,691 vs $80,082±$2,091; P=.0003). Mortality during readmission was 3.6% (n=74). Indications for readmission were most commonly cardiac (26.2%), infectious (17.8%), and pulmonary (11.7%). Multivariable analysis identified 2 independent risk factors for readmission: acute kidney injury (OR 1.49; 95% CI 1.24-1.78, P<.0001) and an Elixhauser Comorbidity Index >4 (OR 1.26; 95% CI 1.06-1.49, P=.009).

CONCLUSIONS

After surgical repair of TAAD, approximately 30% of patients were readmitted within 90 days, two thirds of them during the 31- to 90-day period. Targeted improvements in perioperative care and post-discharge follow-up of patients with multiple comorbidities could mitigate readmission rates. Efforts to reduce readmissions should be continued throughout the 90-day period.

National trends in repair for type B aortic dissection

Background

Thoracic endovascular aortic repair (TEVAR) first gained in popularity for repair of type B aortic dissections (TBADs) in the early 2000's. We aimed to describe patients undergoing open repair, TEVAR, and no repair and analyze factors associated with repair within 14 days of presentation in the contemporary era.

Methods

We used the MarketScan database to find patients with TBAD between 2014 and 2017. To assess factors associated with early repair, univariable, and multivariable log‐binomial regression were used.

Results

There were 2613 patients admitted with TBAD between 2014 and 2017 across the United States, of whom 38.4% underwent repair within 14 days of admission (25.3% open repair and 13.1% TEVAR). The incidence of repair within 14 days decreased over the study period (43% of the study cohort in 2014 to 26.4% in 2017) primarily due to a decrease in open repairs from 30.8% of patients in 2014 to 12.5% in 2017. In multivariable analysis, older age, Middle Atlantic location, diabetes mellitus, insulin use, antiplatelet use, and more recent year were associated with lower likelihood of early repair; male sex, peripheral vascular disease, and the presence of extremity ischemia, rupture, shock, and acidosis were associated with higher likelihood of repair.

Conclusions

Overall, repair of TBAD within 14 days of presentation declined from 2014 to 2017, with a steady rate of TEVAR but declining rate of open repairs. Further investigation into provider‐ and hospital‐specific factors as they relate to likelihood of repair is needed.

Location of death among patients presenting with cardiovascular disease to the emergency department in the United states

BACKGROUND

In-hospital deaths are an important outcome and little is known about deaths in the emergency department (ED). Among patients who died of cardiovascular diseases (CVD), we assessed causes of death, temporal trends and the relative distribution of deaths in the ED versus hospital.

METHODS

Using the United States Nationwide Emergency Department Sample, we conducted a retrospective study of patients presenting to the ED with a primary diagnosis of CVD between 2006 and 2014. We used descriptive statistics to describe causes of deaths, temporal trends and location of death.

RESULTS

During the study period, there were 27 144 508 visits to the ED with CVD diagnoses (~2% of all ED visits,). The most common CVD diagnoses were heart failure (n = 8 571 598), acute myocardial infarction (n = 4 827 518) and atrial fibrillation/flutter (n = 4 713 241). There were a total of 2.2 million deaths caused by the CVD, with the majority (57.6%) occurring in the ED. Cardiac arrest was the most common cause of in-hospital death (n = 1 225 095, 55.3%), followed by acute myocardial infarction (n = 279 310, 12.6%), heart failure (n = 217 367, 9.8%), intracranial hemorrhage (n = 168 009, 7.6%) and ischemic stroke (n = 151 615, 6.8%). The proportion of deaths in the ED for these causes were 91.9% cardiac arrest (n = 1 173 471), 3.6% acute myocardial infarction (n = 46 909), 1.0% heart failure (n = 12 599) and 1.1% intracranial hemorrhage (n = 13 579). There was a decrease in death for most CVDs over time.

CONCLUSIONS

Inpatient CVD admissions and their associated death may not be a robust measure of the national burden of CVD since ED death-which are common for some conditions-are not captured.

Burden and causes of readmissions following initial discharge after aortic syndromes

BACKGROUND

Aortic syndromes, including aortic dissection (AD), intramural hematoma (IMH), and penetrating aortic ulcer (PAU), carry significant morbidity and mortality; few data exist regarding burden and causes of related rehospitalizations following initial discharge.

METHODS

The study was conducted using the Rochester Epidemiology Project. All adult residents (age ≥18 years) with an incident diagnosis of AD, IMH, and PAU (1995-2015) were identified from the Rochester Epidemiology Project using the International Classification of Diseases, Ninth Revision and Tenth Revision codes and Hospital Adaptation of the International Classification of Diseases, second edition, codes. Assessment of any-cause (aortic and cardiovascular), aorta-related, or cardiovascular-related readmissions was determined following date of hospital discharge or diagnosis date (ie, the index event).

RESULTS

A total of 117 patients of 130 cases of AD, IMH, and PAU included in the initial study population survived the index event and were evaluated. The median age of diagnosis was 74 years, and 70 (60%) were male. A total of 79 patients (68%) experienced at least one readmission. The median time to first any-cause, cardiovascular, and aortic readmission was 143, 861, and 171 days, respectively. The cumulative incidence of any-cause readmissions at 2, 4, and 10 years was 45%, 55%, and 69%, respectively. The cumulative incidence of cardiovascular readmissions at 2, 4, and 10 years was 15%, 20%, and 28%, respectively. The cumulative incidence of aortic readmissions at 2, 4, and 10 years was 38%, 46%, and 59%, respectively. Overall survival for the entire cohort at 2, 4, and 10 years was 84%, 75%, and 50%, respectively.

CONCLUSIONS

Readmissions following initial discharge after diagnosis of aortic syndrome are common and not different across specific disease types. Whereas aorta-related rehospitalizations occur in more than half of patients but tend to be earlier, cardiovascular-related rehospitalizations tend to happen later in about one-third of patients. This may suggest the need for early follow-up focused on aortic complications, whereas later follow-up should address cardiovascular events.

Aortic Dissection and Other Acute Aortic Syndromes: Diagnostic Imaging Findings from Acute to Chronic Longitudinal Progression

Acute aortic dissection is the prototype of acute aortic syndromes (AASs), which include intramural hematoma, limited intimal tear, penetrating atherosclerotic ulcer, traumatic or iatrogenic aortic dissection, and leaking or ruptured aortic aneurysm. The manifestation is usually sudden and catastrophic with acutely severe tearing chest or back pain. However, clinical symptoms do not allow distinction between AAS types and other acute pathologic conditions. Diagnostic imaging is essential to rapidly confirm and accurately diagnose the type, magnitude, and complications of AASs. CT fast acquisition of volumetric datasets has become instrumental in diagnosis, surveillance, and intervention planning. Most critical findings affecting initial intervention and prognosis are obtained at CT, including involvement of the ascending aorta, primary intimal tear location, rupture, malperfusion, size and patency of the false lumen, complexity and extent of the dissection, maximum caliber of the aorta, and progression or postintervention complications. Involvement of the ascending aorta-Stanford type A-has the most rapid lethal complications and requires surgical intervention to affect its morbidity and mortality. Lesions not involving the ascending aorta-Stanford type B-have a lesser rate of complications in the acute phase. During the acute to longitudinal progression, various specific and nonspecific imaging findings are encountered, including pleural and pericardial effusions, fluid collections, progression including aortic enlargement, and postoperative changes that can be discerned at CT. A systematic analysis algorithm is proposed for CT of the entire aorta throughout the continuum of AASs into the chronic and posttreated disease state, which synthesizes and communicates salient findings to all care providers. Online supplemental material is available for this article. ^©RSNA, 2021.

Low Serum-Free Testosterone Concentration in Chinese Male Patients with Uncomplicated Acute Type B Aortic Dissection

OBJECTIVE

Although aortic dissection occurs predominantly in men, its association with androgens is unknown. The aim of this study was to evaluate the androgen levels in Chinese male patients with uncomplicated, acute type B aortic dissection.

STUDY DESIGN

Cross-sectional study.

MATERIALS AND METHODS

A total of 192 age-matched male patients with uncomplicated, acute type B aortic dissection or essential hypertension were recruited between 2016 and 2018. The demographic and clinical data were analyzed.

RESULTS

Male patients with uncomplicated, acute type B aortic dissection had lower serum total testosterone and free testosterone than male patients with essential hypertension (7.6 ± 3.7 nmol/L vs. 10.9 ± 3.8 nmol/L, P < 0.001; 36.0 ± 19.8 pmol/L vs. 56.4 ± 19.2 pmol/L, P < 0.001). Lower free testosterone level was significantly associated with uncomplicated, acute type B aortic dissection (univariate odds ratio 0.948, P < 0.001; multivariate odds ratio = 0.966, P = 0.002). No statistical difference was observed for free testosterone between younger patient groups (aged < 51 years; aged 51-60 years) and older patient groups (aged 61-70 years; aged >70 years) with uncomplicated, acute type B aortic dissection (33.7 ± 19.8 pmol/L vs. 38.5 ± 19.8 pmol/L, P = 0.239).

CONCLUSIONS

Lower free testosterone was independently associated with uncomplicated, acute type B aortic dissection in the Chinese male population with hypertension. Additional studies are needed to clarify whether earlier onset in Chinese patients with aortic dissection is associated with androgen deficiency.

Review of Studies Reporting the Incidence of Acute Type B Aortic Dissection

Aortic dissection (AD) causes more deaths each year in the United Kingdom than road traffic collisions. Yet the incidence of AD is not known. The management of acute type B AD (TBAD) is changing, with the greater use of thoracic aortic stent grafts (TEVAR) in treatment and fewer open surgical procedures performed. The study’s aim is to review the worldwide, English language published, literature on acute TBAD incidence and treatment, to report on its strengths and limitations, and better understand changes in incidence over time and between countries. Thirty-one studies were identified that focus on the epidemiology and treatment of TBAD. Eight of these studies report the incidence of acute TBAD as between of 0.5–6.3 per 100,000 person years. Hospital admissions for aortic dissection are reported to be increasing in six studies and stable in one study. The proportion of patients with TBAD operated on varies between studies (range 13% to 76%). Studies identify patient age (median 51–77 years), gender (range 48%–81% male) and prevalence of cardio-vascular risk factors, specifically hypertension, in the populations studied as independent factors influencing aortic dissection incidence. Treatment of acute TBAD remains largely conservative with analgesia, hypertension control and serial cross-sectional imaging (range 24%–87% TBAD medically treated). The use of TEVAR to treat acute AD is increasing worldwide (range 13%–76% TBAD treated with TEVAR). The incidence of TBAD is under-reported due to out of hospital deaths, variable clinical presentation (miss-diagnosis) and coding errors. Importantly for research, the single International Classification of Diseases (ICD) code for aortic dissection, I17.0, does not distinguish between acute, chronic, type A or type B dissection types. Similarly, the OPCS Classification of Interventions and Procedures version 4 (OPCS-4) codes for TEVAR, L27.4 and L28.4, do not distinguish between acute and chronic AD presentation, unlike the codes for open thoracic aortic replacement. Standardised reporting of aortic dissection type, and the urgency of both the initial presentation (acute or chronic) and treatment (emergency, urgent or planned) in future studies would allow more meaningful comparisons between populations.

Distal bare metal stent implantation during thoracic endovascular aortic repair is beneficial to treat complicated type B aortic dissection: A systematic review and meta-analysis

OBJECTIVE

To explore whether thoracic endovascular aortic repair (TEVAR) plus distal bare metal stent (BMS) implantation leads to favorable clinical outcomes compared with standard TEVAR in treating acute complicated type B aortic dissection.

METHODS

Relevant publications were found through a precise search of PubMed, Cochrane Library, and EMBASE. Count data were calculated as the odd ratio (OR)and 95% confidence interval (CI) using the Mantel-Haenszel statistical method, quantitative data were calculated as mean difference and 95% CI using Inverse Variance statistical method. When the data heterogeneity was large, with an I² > 50%, a random-effects model and sensitivity analysis were performed. The analysis tool we used was the software Revman 5.3 and G*power 3.1.

RESULTS

There were 7 publications involving 958 patients who were enrolled ultimately. The incidence of unplanned secondary intervention and postoperative adverse events in the TEVAR + BMS were lower than standard TEVAR (OR, 0.42, (95% CI, 0.23 to 0.75); OR, 0.57, (95% CI, 0.37 to 0.90)), and the pooled number needed to treat was 15 for unplanned secondary intervention and 15 for postoperative adverse events. There were no significant difference in the aortic-related or all-cause 30-day mortality (OR, 0.81, (95% CI, 0.25 to 2.61); OR, 0.47, (95% CI, 0.18 to 1.22)), aortic-related, all-cause mortality at least 6 months or incidence of the postoperative endoleak (OR, 0.47, (95% CI, 0.17 to 1.32); OR, 0.42, (95% CI, 0.17 to 1.06); OR, 0.81, (95% CI, 0.32 to 2.05)).

CONCLUSION

There is no significant outcome difference except for reduced reintervention but this does not seem to adversely affect survival. It is unclear whether this justifies the additional cost of placing it in every complicated type B aortic dissection regardless of anatomy after standard TEVAR alone. Besides, more data are needed to verify the adjunctive distal bare metal stents' performance at different dissection stages.

Incidence and Mortality Rates of Thoracic Aortic Dissection in Korea - Inferred from the Nationwide Health Insurance Claims

BACKGROUND

Aortic dissection (AD) is one of the most catastrophic diseases and is associated with high morbidity and mortality. The aim of this study is to investigate the hospital incidence and mortality rates of thoracic AD in Korea using a nationwide database.

METHODS

We conducted a nationwide population-based study using the health claims data of the National Health Insurance Service in Korea. From 2005 to 2016, adult patients newly diagnosed with AD were included. All patients were divided into the following four subgroups by treatment: type A surgical repair (TASR), type B surgical repair (TBSR), thoracic endovascular aortic repair (TEVAR), and medical management (MM). The incidence rate, mortality rate, and risk factors of in-hospital mortality were evaluated.

RESULTS

In total, 18,565 patients were newly diagnosed with AD (TASR, n = 4,319 [23.3%]; TBSR, n = 186 [1.0%]; TEVAR, n = 697 [3.8%]; MM, n = 13,363 [72.0%]). The overall AD incidence rate was 3.76 per 100,000 person-years and exhibited a gradual increase during the study period (3.29 to 4.82, P < 0.001). The overall in-hospital mortality rate was 10.84% and remained consistent (P = 0.57). However, the in-hospital mortality rate decreased in the TASR subgroup (18.23 to 11.27%, P = 0.046). An older age, the female sex, hypertension, and chronic kidney disease were independent risk factors for in-hospital mortality.

CONCLUSION

The incidence of thoracic AD has gradually increased in Korea. The in-hospital mortality in the TASR subgroup decreased over the decade, although the overall mortality of AD patients did not change.

Incidence and characteristics of hospitalization for proximal aortic surgery for acute syndromes and for aneurysms in the USA from 2005 to 2014

OBJECTIVES

The effectiveness of proximal thoracic aortic aneurysm (TAA) surgery in preventing acute aortic syndromes, such as dissection and rupture, is unknown at the populational level. This study evaluated trends in acute aortic syndrome operation incidence relative to proximal aortic surgical volume in the USA.

METHODS

A retrospective analysis of the National Inpatient Sample in 2005-2014 was performed. Acute aortic syndrome and TAA were identified with International Classification of Diseases, 9th edition diagnosis codes. Proximal aortic surgery was defined as the diagnosis of acute aortic syndrome or TAA with an aortic procedure and either cardioplegia, cardiopulmonary bypass or other cardiac operation. Annual rates of acute aortic syndrome surgery and proximal thoracic aneurysm surgery were adjusted for US population. Trends were evaluated using linear regression.

RESULTS

We identified 38 442 operations for acute aortic diagnoses and 74 953 operations for TAAs. Case volume for acute aortic syndromes increased from 0.93 to 1.63 per 100 000 (P = 0.001), and aneurysm surgery increased from 1.75 to 3.19 per 100 000 (P < 0.001). Patient and hospital characteristics differed between acute aortic and aneurysm operations, with black patients being most notably underrepresented in the aneurysm population (4.9% vs 17.0%, P < 0.001).

CONCLUSIONS

Acute aortic syndrome operative volume increased from 2005 to 2014 despite increasing rates of proximal aortic aneurysm surgery. Patient characteristic discrepancies were observed between the 2 groups of hospitalizations, highlighting the need for continued efforts to minimize sociodemographic disparities.

The Role of Sirtuin-1 in the Vasculature: Focus on Aortic Aneurysm

Sirtuin-1 (SirT1) is a nicotinamide adenine dinucleotide-dependent deacetylase and the best characterized member of the sirtuins family in mammalians. Sirtuin-1 shuttles between the cytoplasm and the nucleus, where it deacetylates histones and non-histone proteins involved in a plethora of cellular processes, including survival, growth, metabolism, senescence, and stress resistance. In this brief review, we summarize the current knowledge on the anti-oxidant, anti-inflammatory, anti-apoptotic, and anti-senescence effects of SirT1 with an emphasis on vascular diseases. Specifically, we describe recent research advances on SirT1-mediated molecular mechanisms in aortic aneurysm (AA), and how these processes relate to oxidant stress and the heme-oxygenase (HO) system. HO-1 and HO-2 catalyze the rate-limiting step of cellular heme degradation and, similar to SirT1, HO-1 exerts beneficial effects in the vasculature through the activation of anti-oxidant, anti-inflammatory, anti-apoptotic, and anti-proliferative signaling pathways. SirT1 and HO-1 are part of an integrated system for cellular stress tolerance, and may positively interact to regulate vascular function. We further discuss sex differences in HO-1 and SirT1 activity or expression, and the potential interactions between the two proteins, in relation to the progression and severity of AA, as well as the ongoing efforts for translational applications of SirT1 activation and HO-1 induction in the treatment of cardiovascular diseases including AA.

Hospital Incidence and In-Hospital Mortality of Surgically and Interventionally Treated Aortic Dissections: Secondary Data Analysis of the Nationwide German Diagnosis-Related Group Statistics From 2006 to 2014

Background

Population‐based data about the incidence and mortality of patients with aortic dissections (ADs) are sparse. Therefore, the hospital incidence and in‐hospital mortality of patients undergoing open or endovascular surgery for type A ADs (TAADs) and type B ADs (TBADs) in Germany were analyzed on a nationwide basis between 2006 and 2014.

Methods and Results

A secondary data analysis of the nationwide diagnosis‐related group statistics, compiled by the German Federal Statistical Office, was performed for patients who were surgically/interventionally treated for AD (International Classification of Diseases, Tenth Revision, German Modification [ICD‐10‐GM] codes I71.00‐I71.07; n=20 533). By using specific procedure codes, a distinction between TAAD (n=14 911/72.6%) and TBAD (n=5622/27.4%) could be made. The standardized hospital incidence of surgically/interventionally treated AD was 2.7/100 000 per year, comprising 2.0/100 000 per year for TAAD and 0.7/100 000 per year for TBAD. The in‐hospital mortality of TAAD was 19.5%; and of TBAD, 9.3%. Both the incidence and in‐hospital mortality increased over the 9‐year period. The share of endovascularly treated TBAD increased steadily during the same time interval. A multilevel multivariable analysis revealed that, for TAAD, age and comorbidity were significantly associated with a higher mortality risk.

The latter was also true for TBAD. Sex was not significantly associated with mortality. A significant association between higher annual center volume and mortality was found for TAAD, but not for TBAD.

Conclusions

This is the first report on hospital incidence and mortality for surgically/interventionally treated AD on a nationwide basis. Overall, in Germany, hospital incidence and mortality of TAAD and TBAD increased over time. In addition, TAAD is performed more safely in high‐volume centers.

See Editorial Svensson

The blood protective effect of autologous platelet separation in aortic dissection

OBJECTIVE

This study aimed to retrospectively analyze the blood protective effect of autologous platelet separation in operations for acute aortic dissection.

METHODS

A total of 130 patients with acute aortic dissection were enrolled into the present study. The average age of these patients was 52.962±10.5061 years old. These patients underwent the modified aortic arch replacement with the elephant trunk technique or endovascular aortic exclusion with covered stent. Among these patients, 68 patients who underwent autologous platelet separation were assigned to the platelet separation group, while the remaining patients were assigned to the control group. All operations were performed under deep hypothermic circulatory arrest. After anesthesia, 1-2 therapeutic doses of autologous platelets were isolated from patients in the platelet separation group, and these platelets were quickly infused back to these patients after heparin was neutralized by protamine at the end of the cardiopulmonary bypass. The preoperative and postoperative indexes in these two groups were compared.

RESULTS

There were no statistically significant differences in age, gender, smoking history, drinking history and hypertension history between these two groups. Compared with controls, the transfusion volume of allogeneic platelets in the perioperative period significantly decreased in the platelet separation group (1.919±1.6226 vs. 0.794±1.1789, P < #x003C;< #x200A;0.05), and the use rate of allogeneic platelets also significantly decreased (74.19% vs. 45.59%, P < #x003C;< #x200A;0.05).

CONCLUSION

The intraoperative auto transfusion of platelets significantly reduced the volume of allogeneic platelet transfusion after the operation for aortic dissection, which has a significant blood protective effect.

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.

Impact of center volume on outcomes of surgical repair for type A acute aortic dissections

BACKGROUND

Acute type A aortic dissection is a cardiovascular emergency requiring operative intervention. Despite advancements in operative technique and increased specialization of cardiovascular care, operative mortality, and morbidity after repair of type A aortic dissection remain high. Our aim was to assess national trends in outcomes of type A aortic dissection repair and the impact of institutional thoracic aortic repair volume on clinical outcomes and resource use in the United States.

METHODS

Using the procedural and diagnostic codes of the International Classification of Diseases, Ninth Revision, we identified type A aortic dissection repairs from the 2005 to 2014 database of the National Inpatient Sample. Hospitals were classified into low-, medium- and high-volume tertiles based on annual incidence of thoracic aortic operations. Patient demographics and hospital characteristics, as well as outcomes including mortality, cost, and duration of stay, were evaluated using parametric tests for trends and the volume-outcome relationship. We used a multivariable-adjusted logistic regression model to identify factors associated with mortality.

RESULTS

An estimated 25,231 patients received type A aortic dissection repair with an increasing temporal trend in volume and concomitant decrease in mortality. When stratified by hospital volume, 10,115 (40.1%), 8,194 (32.4%), and 6,920 (27.4%) underwent type A aortic dissection at low-volume, medium-volume, and high-volume, respectively. The unadjusted mortality rate in high-volume was the least (21.5% vs 16.8% vs 11.6% for low-volume, medium-volume, and high-volume, respectively; P < .001). Multivariable analysis revealed older age, lesser household incomes and comorbidities, including congestive heart failure (adjusted odds ratio 1.44; P < .001) and coagulopathy (adjusted odds ratio 1.33; P = .01) as statistically significant predictors of mortality; however, the risk-adjusted duration of stay (adjusted odds ratio 0.88; P = .06) was not different between low-volume and high-volume hospitals. After adjusting for patient and hospital characteristics, type A aortic dissection repair at low-volume hospitals was associated with increased likelihood of mortality compared with high-volume hospitals (adjusted odds ratio 2.10; P < .001). Patients undergoing type A aortic dissection repair at low-volume hospitals had increased odds of all complications including stroke, and respiratory complications compared than those at high-volume hospitals (P = .02, P < .001, and P < .001, respectively).

CONCLUSION

The volume of open surgical repair for type A aortic dissection in the United States has increased over the past decade, while mortality has decreased. Hospital aortic operative volume is strongly associated with outcomes for type A aortic dissection repair. Protocols for expeditious transfer of patients to high volume aortic centers may serve to further decrease the acute mortality and complications of this procedure.

Incidence of acute type A aortic dissection in emergency departments

Due to the symptoms, patients with acute type A aortic dissection are first seen by the ambulance service and diagnosed at the emergency department. How often an aortic dissection occurs in an emergency department per year has been studied. The incidence in the emergency department may be used as a quality marker of differential diagnostics of acute chest pain. A multi-institutional retrospective study with the municipal Berlin hospital chain Vivantes and its Department of Pathology and the Charité - University Medicine Berlin was performed. From the Berlin Hospital Society, the annual numbers of publicly insured emergency patients were obtained. Between 2006 and 2016, 631 aortic dissections were identified. The total number of patients treated in the emergency departments (n = 12,790,577) was used to calculate the “emergency department incidence.” The autopsy data from six clinics allowed an estimate on how many acute type A aortic dissections remained undetected. Across all Berlin hospitals, the emergency department incidence of acute type A aortic dissection was 5.24 cases in 100,000 patients per year. In tertiary referral hospitals and, particularly, in university hospitals the respective incidences were markedly higher (6.7 and 12.4, respectively). Based on the autopsy results, about 50% of the acute type A aortic dissection may remain undetected, which would double the reported incidences. Among different hospital types the emergency department incidences of acute type A aortic dissection vary between 5.93/100,000 and 24.92/100,000. Aortic dissection; Incidence; Emergency Department; Epidemiology

Impact of patient factors and procedure on readmission after aortic dissection admission in the states of Florida and New York

BACKGROUND

Readmissions after aortic dissection (AD) admission are not well described. Using state-based administrative claims data, we sought to define readmission rates after AD and to identify factors associated with them.

METHODS

State Inpatient Databases for Florida (2007-2012) and New York (2008-2012) were queried for AD index admissions. Admissions were stratified by initial treatment strategy: type A open surgery repair (TAOR), type B open surgery repair (TBOR), thoracic endovascular aortic repair (TEVAR), or medical management (MM). All-cause readmission rates were calculated at 30 days, 90 days, and 2 years. Logistic regression was used to identify factors associated with readmission at each time point for all type A admissions (TAOR) or type B admissions (TBOR, TEVAR, MM).

RESULTS

We identified 4670 patients with an AD index admission. Treatment was with TAOR in 1031 (22%), TBOR in 761 (16%), TEVAR in 412 (9%), and MM in 2466 (53%). Patients were predominantly male (59.4%) and white (61.9%), with a median age of 66 years. Overall mortality during AD index admission was 14.8% (TAOR, 15.8%; TBOR, 17.1%; TEVAR, 9.0%; MM, 14.7%; P = .002 across all groups). All-cause readmission rates were similar across treatment groups at 30 days (9.6%-11%; P = .56), 90 days (15.2%-20%; P = .26), and 2 years (49.2%-54.4%; P = .15). Higher income quartile (vs lowest) was associated with lower odds of early readmission (at 30 days and 90 days) after type B admissions but not after type A admissions. At 2 years, self-pay (vs Medicare) was associated with lower odds of readmission in both type A and type B admissions, whereas higher comorbidity count and black race (vs white) were associated with higher odds of readmission. TEVAR (vs MM) was also associated with higher odds of readmission. Cardiovascular disease was the most common cause for readmission at all time points. Emergency department readmission counts were highest after MM admissions, and ambulatory surgical admissions were highest after TBOR. Both TEVAR and MM initial costs were lower than TAOR and TBOR costs, but at 2 years, costs remained significantly lower only for MM.

CONCLUSIONS

In-state 30-day, 90-day, and 2-year readmission rates after AD were not associated with initial treatment type. Two-year readmissions are common. Strategies to target socioeconomic, race, and geographic factors may reduce variations in readmission patterns after AD admission.

Association between fine particulate matter air pollution and acute aortic dissections: A time-series study in Shanghai, China

It remains unknown whether ambient air pollution could induce the onset of acute aortic dissection (AAD). This study aimed to investigate the potential association between fine particulate matter (PM_2.5) and AAD onset. We collected new episodes of AAD between January 1, 2014 and December 31, 2018 from the emergency department of a major hospital in Shanghai, China. The overdispersed generalized additive model was used to estimate the association between PM_2.5 and AAD emergency hospitalizations and was adjusted for time trends and weather conditions. During the study period, we identified a total of 1335 cases of AAD hospitalizations and recorded an average PM_2.5 concentration of 45 ± 30 μg/m³. The association was statistically significant on the concurrent day of hospital admission, remained on the lag 1 day. For the average of the two lags, a 10 μg/m³ increase of PM_2.5 was associated with 3.38% (95% confidence interval: 1.02%, 5.79%) increase of AAD hospitalizations. The association between PM_2.5 and AAD remained when adjusting for the concomitant exposures to coarse particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide and ozone. The concentration-response curves increased apparently when daily PM_2.5 concentration was beyond the China's National Ambient Air Quality Standard (35 μg/m³). In stratified analyses, the significant association was only present among elders and males, and during cool season. This investigation demonstrated a significant and robust association between short-term PM_2.5 exposure and increased AAD hospitalizations in Shanghai, China. Our findings have important implications for the prevention of AAD.

Comparison of Femoral and Axillary Artery Cannulation in Acute Type A Aortic Dissection Surgery

INTRODUCTION

One of the most important points of the acute type A aortic dissection surgery is how to perform cannulation regarding cerebral protection concerns and the conditions of arterial structures as a pathophysiological consequence of the disease.

OBJECTIVE

In this study, femoral and axillary cannulation methods were compared in acute type A aortic dissection operations.

METHODS

The study retrospectively evaluated 52 patients who underwent emergency surgery for acute type A aortic dissection. Patients without malperfusion according to Penn Aa classification were chosen for preoperative standardization of the study groups. The femoral arterial cannulation group was group 1 (n=22) and the axillary arterial cannulation group was group 2 (n=30). The groups were compared in terms of perioperative and postoperative results.

RESULTS

There was no statistically significant difference in terms of preoperative data. In terms of postoperative parameters, especially early mortality and new-onset cerebrovascular event, there was no statistically significant difference. Mortality rates in group 1 and group 2 were 13.6% (n=3) and 10% (n=3), respectively (P=0.685). Postoperative new-onset cerebral events ratio was found in 5 (22.7%) in the femoral cannulation group and 6 (20%) in the axillary cannulation group (P=0.812).

CONCLUSION

Both femoral and axillary arterial cannulation methods can be safely performed in patients with acute type A aortic dissection, provided that cerebral protection strategies should be considered in the first place. The method to be performed may vary depending on the patient's current medical condition or the surgeon's preference.

Readmissions after acute type B aortic dissection

OBJECTIVE

Acute type B aortic dissection can be treated with medical management alone, open surgical repair, or thoracic endovascular aortic repair (TEVAR). The nationwide burden of readmissions after acute type B aortic dissection has not been comprehensively assessed.

METHODS

We analyzed adults with a hospitalization due to acute type B aortic dissection between January 1, 2010, and December 31, 2014, in the Nationwide Readmissions Database. International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify hospitalizations with a primary diagnosis code for thoracic or thoracoabdominal aortic dissection. The primary outcome was nonelective 90-day readmission. Predictors of readmission were determined using hierarchical logistic regression.

RESULTS

The study population consisted of 6937 patients with unplanned admissions for type B aortic dissections from 2010 through 2014. Medical management alone was the treatment for 62.6% of patients, 21.0% had open surgical repair, and 16.4% underwent TEVAR. Nonelective 90-day readmission rate was 25.1% (23.6% with medical management alone, 26.9% with open repair, and 28.7% with TEVAR; P < .001). An additional 4.7% of patients were electively readmitted. The most common cause for nonelective readmission was new or recurrent arterial aneurysm or dissection (24.8%). Of those with unplanned readmissions, 5.2% underwent an aortic procedure. The mortality rate during nonelective readmission was 5.0%, and the mean cost of the rehospitalization was $22,572 ± $41,598.

CONCLUSIONS

More than one in four patients have a nonelective readmission 90 days after hospitalization for acute type B aortic dissection. Absolute rates of readmission varied by initial treatment received but were high irrespective of the initial treatment. The most common cause of readmission was aortic disease, particularly among those treated with medication alone. Further research is required to determine potential interventions to decrease these costly and morbid readmissions, including the role of multidisciplinary aortic teams.

Population-Based Assessment of the Incidence of Aortic Dissection, Intramural Hematoma, and Penetrating Ulcer, and Its Associated Mortality From 1995 to 2015

Background Aortic syndromes (ASs), including aortic dissection, intramural hematoma, and penetrating aortic ulcer, carry significant acute and long-term morbidity and mortality. However, the contemporary incidence and outcomes of AS are unknown. Methods and Results We used the Rochester Epidemiology Project record linkage system to identify all Olmsted County, MN, residents with AS (1995-2015). Diagnostic imaging, medical records, and death certificates were reviewed to confirm the diagnosis and AS subtype. Age- and sex-adjusted incidence rates were estimated using annual county-level census data. Survival for patients with AS was compared with age- and sex-matched controls using Cox regression to adjust for comorbid conditions. We identified 133 patients with AS (77, aortic dissection; 21, intramural hematoma; and 35, penetrating aortic ulcer). Average age was 71.8 years (SD=14.1), and 57% were men. The age- and sex-adjusted incidence was 7.7 per 100 000 person-years, was higher for men than women (10.2 versus 5.7 per 100 000 person-years), and increased with age. Among subtypes, the incidence of aortic dissection was highest (4.4 per 100 000 person-years), whereas the incidence of penetrating aortic ulcer and intramural hematoma was lower (2.1 and 1.2 per 100 000 person-years). Overall, the incidence of AS was stable over time ( P trend=0.33), although the incidence of penetrating aortic ulcer seemed to increase from 0.6 to 2.6 per 100 000 person-years ( P=0.008) with variability over the study interval. Patients with AS had more than twice the mortality rate at 5, 10, and 20 years when compared with population-based controls (5-, 10-, and 20-year mortality 39%, 57%, and 91% versus 18%, 41%, and 66%; overall adjusted mortality hazards ratio=2.1; P<0.001). Survival was lower than expected up to 90 days after AS diagnosis and did not differ significantly by subtype or by 5-year strata of diagnosis. Conclusions Overall, the incidence of aortic dissection and intramural hematoma has remained stable since 1995, despite the decline noted for other cardiovascular disease. AS confers increased early and long-term mortality that has not changed. These data highlight the need to improve long-term care to impact the prognosis of this patient group.

Volume-Outcome Relationships in Surgical and Endovascular Repair of Aortic Dissection

BACKGROUND

As surgical mortality decreases and endovascular utilization increases, it is unknown whether volume-outcome relationships exist in thoracic aortic dissection repair. We characterized volume-outcome relationships for surgical and endovascular management of thoracic aortic dissection.

METHODS

Patients aged more than 18 years undergoing repair of thoracic aortic dissection in the United States between 2010 and 2014 were identified in seven all-payer state inpatient administrative databases. Patients were divided into groups based on type of repair: surgical repair of type A dissection (TAAD), surgical repair of type B dissection (TBAD), and endovascular repair (TEVAR). Hierarchical logistic regression models evaluated the association between hospital volume and in-hospital mortality.

RESULTS

Overall in-hospital mortality rate was 13.4% (890 of 6650), highest after TAAD (463 of 2918, 15.9%), followed by TBAD (270 of 1934, 14.0%) and TEVAR (157 of 1798, 8.7%). Volume-outcome relationships for adjusted in-hospital mortality were demonstrated for TAAD and TBAD (P-trend < .001), but not TEVAR (P-trend = .11). Adjusted in-hospital mortality differed most for TAAD (fewer than 3 cases per year: 21%, 95% confidence interval, 18% to 24%; vs 11 or more cases per year: 12%, 95% confidence interval, 8% to 16%; P < .001) and TBAD (fewer than 2 cases per year: 18%, 95% confidence interval, 15% to 22%; vs 11 or more cases per year: 9%, 95% confidence interval, 5% to 12%; P < .001), whereas TEVAR did not differ between quartiles. Adjusted mortality was lower at centers with 26 or more overall annual thoracic dissection repairs, compared with any of the three lower-volume quartiles (P < .001).

CONCLUSIONS

This study demonstrated lower mortality at high-volume hospitals for overall repair of aortic dissection, persisting separately for surgical repair of TAAD and TBAD, but not TEVAR. As endovascular technology advances and practice patterns consequently change, analyses should focus on understanding the balance between procedural volume, mortality, and access to care for thoracic aortic dissection.

Successful Repair of Type A Aortic Dissection in an Octogenarian With Double Aortic Arch

An 80-year-old woman was transferred to our institution with a subacute type A aortic dissection and a previously undiagnosed double aortic arch. The patient underwent successful repair with aortic valve resuspension, ascending aortic replacement, and repair of the proximal right-sided arch. This is the first reported case of a type A dissection associated with a double aortic arch in the United States.

Oxygenation impairment after total arch replacement with a stented elephant trunk for type-A dissection

OBJECTIVE

To study the risk factors of oxygenation impairment in patients with type-A acute aortic dissection who underwent total arch replacement with a stented elephant trunk.

METHODS

In this study, 169 consecutive patients were enrolled who were diagnosed with type-A acute aortic dissection and underwent a total arch replacement procedure at the Qilu Hospital of Shandong University between January 2015 and February 2017. Postoperative oxygenation impairment was defined as arterial oxygen partial pressure/inspired oxygen fraction ≤ 200 with positive end expiratory pressure ≥ 5 cm H₂O that occurred within 72 hours of surgery. Perioperative clinical characteristics of all patients were collected and univariable analyses were performed. Risk factors associated with oxygenation impairment identified by univariable analyses were included in the multivariable regression analysis.

RESULTS

The incidence of postoperative oxygenation impairment was 48.5%. Postoperative oxygenation impairment was associated with prolonged mechanical ventilation time, intensive care unit stay, and hospital stay. Multivariable regression analysis demonstrated that body mass index (odds ratio [OR], 1.204; 95% confidence interval [CI], 1.065-1.361; P = .003), preoperative oxygenation impairment (OR, 9.768; 95% CI, 4.159-22.941; P < .001), preoperative homocysteine (OR, 1.080; 95% CI, 1.006-1.158; P = .032), circulatory arrest time (OR, 1.123; 95% CI, 1.044-1.207; P = .002), and plasma transfusion (OR, 1.002; 95% CI, 1.001-1.003; P = .002) were significantly associated with postoperative oxygenation impairment.

CONCLUSIONS

Postoperative oxygenation impairment is a common complication of surgery for type-A acute aortic dissection. Body mass index, preoperative oxygenation impairment, preoperative homocysteine, circulatory arrest time, and plasma transfusion were independent risk factors for oxygenation impairment after a total arch replacement procedure.

Genes Associated with Thoracic Aortic Aneurysm and Dissection: 2018 Update and Clinical Implications

Thoracic aortic aneurysms, with an estimated prevalence in the general population of 1%, are potentially lethal, via rupture or dissection. Over the prior two decades, there has been an exponential increase in our understanding of the genetics of thoracic aortic aneurysm and/or dissection (TAAD). To date, 30 genes have been shown to be associated with the development of TAAD and ∼30% of individuals with nonsyndromic familial TAAD have a pathogenic mutation in one of these genes. This review represents the authors' yearly update summarizing the genes associated with TAAD, including implications for the surgical treatment of TAAD. Molecular genetics will continue to revolutionize the approach to patients afflicted with this devastating disease, permitting the application of genetically personalized aortic care.

Risk factors of pre-operational aortic rupture in acute and subacute Stanford type A aortic dissection patients

Background

Aortic rupture is one of the main causes of early death in acute and subacute Stanford type A aortic dissection (ATAAD) patients. This study aimed to analyze potential risk factors for pre-operational aortic rupture in ATAAD patients.

Methods

We retrospectively reviewed aortic dissection cases treated between May 2013 and May 2016 in Changhai Hospital, Shanghai. A total of 329 patients with ATAAD were included in the final analysis, and 31 patients died of aortic rupture before surgery. Clinical data on basic characteristics, clinical presentation, and biochemical measurements for all 329 patients were analyzed.

Results

The in-hospital aortic rupture rate was 9.4% (31/329), and the rupture accounted for 47% (31/66) of all in-hospital deaths of ATAAD patients. Patients who experienced rupture were significantly older (P<0.001), had lower systolic blood pressure (P=0.040), had more painful manifestation (P<0.001), had more systematic complications [shock (P=0.001), coma (P<0.001), hypoxemia (P=0.006), kidney and liver dysfunctions, and myocardial injury (higher troponin, P=0.009)], and had worse blood coagulability [lower platelet count (P=0.012), longer prothrombin time (P<0.001), and higher D-dimer (P=0.003)]. Multivariable analysis identified the following independent risk factors: shock [odds ratio (OR): 8.12; 95% confidence interval (CI), 1.10-59.85, P=0.040], pain requiring medication (OR: 12.67; 95% CI, 2.43-66.09; P=0.003), troponin level >0.7 ng/mL (OR: 9.28; 95% CI, 1.72-50.06; P=0.010), and D-dimer level ≥10 µg/mL (OR: 13.37; 95% CI, 2.18-81.97; P=0.005).

Conclusions

Aortic rupture accounted for 47% of all in-hospital deaths among patient with ATAAD. Shock, pain requiring medication, a troponin level >0.7 ng/mL and a D-dimer level ≥10 µg/mL are independent risk factors for aortic rupture in these patients.

Regional Practice Patterns and Outcomes of Surgery for Acute Type A Aortic Dissection

BACKGROUND

The surgical management of acute type A aortic dissection is evolving, and many aortic centers of excellence are reporting superior outcomes. We hypothesize that similar trends exist in a multiinstitutional regional consortium.

METHODS

Records for 884 consecutive patients who underwent aortic operations (2003 to 2015) for acute type A aortic dissection were extracted from a regional The Society of Thoracic Surgeons database. Patients were stratified into three equal operative eras. Differences in outcomes and risk factors for morbidity and mortality were determined.

RESULTS

Surgical procedures for type A aortic dissection are increasing in extent and complexity. Aortic root repair was performed in 16% of early era cases compared with 67% currently (p < 0.0001). Similarly, aortic arch repair increased from 27% to 37% cases (p < 0.0001). Cerebral perfusion is currently used in 85% of circulatory arrest cases, most frequently antegrade (57%). Total circulatory arrest times increased (29 minutes vs 31 minutes vs 36 minutes; p = 0.005), but times without cerebral perfusion were stable (12 minutes vs 6 minutes; p = 0.68). Although the operative mortality rate remained stable at 18.9% during the 3 operative eras, there were significant decreases in pneumonia and reoperations (p < 0.05). Predictors of operative mortality and major morbidity are age (odds ratio [OR], 1.04; p < 0.0001), previous stroke (OR, 2.09; p = 0.03), and elevated creatinine (OR, 1.31; p = 0.01). Importantly, the extent of aortic operation did not increase risk for morbidity or mortality.

CONCLUSIONS

Operative morbidity and mortality remain significant for type A aortic dissection, but lower than historical outcomes. The extent of aortic surgery has increased, resulting in adaptive cerebral protection changes in contemporary "real-world" practice.