Successful resection of a primary angiosarcoma of the azygos vein: A case report.

A 63-year-old woman was admitted to our department for the investigation of superior vena cava (SVC) syndrome. Computed tomography revealed an azygos tumor extending into the SVC. Video-assisted thoracic surgery (VATS) was performed to remove the distal end of the azygos vein in the left lateral position, followed by complete resection of the entire tumor under median sternotomy in the supine position. The histological diagnosis was a primary angiosarcoma of the azygos vein. The patient was discharged without any complications and is now alive and tumor-free 24 months after surgery. In addition, contrast-enhanced computed tomography revealed no graft occlusion in the two reconstructed brachiocephalic veins. Thoracoscopic surgery in the lateral position is useful for safe and reliable complete resection of a tumor arising from the azygos vein.

Clinical Features of 544 Patients With Ruptured Aortic Aneurysm　- A Report From the Tokyo Acute Aortic Super Network Database.

BACKGROUND: Epidemiological data on ruptured aortic aneurysms from large-scale studies are scarce. The aims of this study were to: clarify the clinical course of ruptured aortic aneurysms; identify aneurysm site-specific therapies and outcomes; and determine the clinical course of patients receiving conservative therapy.Methods and Results: Using the Tokyo Acute Aortic Super Network database, we retrospectively analyzed 544 patients (mean [±SD] age 78±10 years; 70% male) with ruptured non-dissecting aortic aneurysms (AAs) after excluding those with impending rupture. Patient characteristics, status on admission, therapeutic strategy, and outcomes were evaluated. Shock or pulselessness on admission were observed in 45% of all patients. Conservative therapy, endovascular therapy (EVT), and open surgery (OS) accounted for 32%, 23%, and 42% of cases, respectively, with corresponding mortality rates of 93%, 30%, and 29%. The overall in-hospital mortality rate was 50%. The prevalence of pulselessness was highest (48%) in the ruptured ascending AA group, and in-hospital mortality was the highest (70%) in the ruptured thoracoabdominal AA group. Multivariable logistic regression analysis indicated in-hospital mortality was positively associated with pulselessness (odds ratio [OR] 10.12; 95% confidence interval [CI] 4.09-25.07), and negatively associated with invasive therapy (EVT and OS; OR 0.11; 95% CI 0.06-0.20). CONCLUSIONS: The outcomes of ruptured AAs remain poor; emergency invasive therapy is essential to save lives, although it remains challenging to reduce the risk of death.

Graft Protective and Intercellular Immunomodulatory Effects by Adoptive Transfer of an Agonistic Anti-BTLA mAb (3C10) Induced CD4+CD25+ Regulatory T Cells in Murine Cardiac Allograft Transplant Model.

BACKGROUND: We demonstrated that an agonistic anti-B and T lymphocyte attenuator antibody (3C10) prolonged cardiac survival by inducing regulatory T cells (Treg). However, the mechanisms of immune tolerance in the recipients remained unclear. In this study, we investigated the graft-protective and intercellular immunomodulatory effects of adoptive transfer (AT) of 3C10-induced Tregs in a murine cardiac allograft transplant model. METHODS: Thirty days after transplantation of a C57BL/6 heart into the primary 3C10-treated CBA recipients, splenic CD4+CD25+ cells from these recipients (3C10/AT group) or naïve CBA mice (no-treatment group) were adoptively transferred into secondary CBA recipients with a C57BL/6 heart. To confirm the requirement for 3C10-induced Tregs, we administered an anti-interleukin-2 receptor alpha antibody (PC-61) to secondary CBA recipients. Additionally, histologic and fluorescent staining, cell proliferation analysis, flow cytometry, and donor-specific antibody (DSA) measurements were performed. RESULTS: 3C10/AT-treated CBA recipients resulted in significantly prolonged allograft survival (median survival time [MST], >50 days). Allografts displayed prolonged function with preservation of vessel structure by maintaining high numbers of splenic CD4+CD25+Foxp3+ Treg and intramyocardial CD4+Foxp3+ cells. DSA levels were suppressed in 3C10/AT-treated CBA recipients. Moreover, PC-61 administration resulted in a shorter MSTs of cardiac allograft survivals, a detrimental increase in DSA production, and enhanced expression of programmed cell death (PD)-1. CONCLUSION: AT of 3C10-induced Tregs may be a promising graft-protective strategy to prolong allograft survival and suppress DSA production, driven by the promotion of splenic and graft-infiltrating Tregs and collaboration with PD-1+ T cells and Treg.

Impact of osteoporotic risk in women undergoing transcatheter aortic valve replacement.

Low body weight and advanced age are reported to be among the best predictors of osteoporosis, and osteoporosis self-assessment tool (OST) values are calculated using a simple formula to identify postmenopausal women at increased risk of osteoporosis. In our recent study, we demonstrated an association between fractures and poor outcomes in postmenopausal women following transcatheter aortic valve replacement (TAVR). In this study, we aimed to investigate the osteoporotic risk in women with severe aortic stenosis and determined whether an OST could predict all-cause mortality following TAVR. The study population comprised 619 women who underwent TAVR. Compared to a quarter of patients with diagnosis of osteoporosis, 92.4% of participants were at high risk of osteoporosis based on OST criteria. When divided into tertiles based on OST values, patients in tertile 1 (lowest OST) displayed increased frailty, a higher incidence of multiple fractures, and greater Society of Thoracic Surgeons scores. Estimated all-cause mortality survival rates 3 years post-TAVR were 84.2 ± 3.0%, 89.5 ± 2.6%, and 96.9 ± 1.7% for OST tertiles 1, 2, and 3, respectively (p = 0.001). Multivariate analysis showed that the OST tertile 3 was associated with decreased risk of all-cause mortality compared with OST tertile 1 as the referent. Notably, a history of osteoporosis was not associated with all-cause mortality. Patients with high osteoporotic risk are highly prevalent among those with aortic stenosis according to the OST criteria. OST value is a useful marker for predicting all-cause mortality in patients undergoing TAVR.

Frailty assessment using photographs in patients undergoing transcatheter aortic valve replacement.

BACKGROUND: When frailty is considered in patient selection, better outcomes are achieved in transcatheter aortic valve replacement (TAVR) procedures. This study investigated whether patient photographs could be utilized to qualitatively assess patient frailty and independently predict poor outcomes following TAVR. METHODS: This study included 1345 patients with severe aortic stenosis who underwent TAVR at the Sakakibara Heart Institute, Japan, between 2013 and 2022. Patient photographs were taken prior to the initial outpatient clinic examination or at discharge in case the patient's first visit was unplanned admission. Frailty was assessed from patient photographs using a four-point photographic frailty scale; 1 (non-frail), 2 (vulnerable), 3 (mild frail), and 4 (frail). Photographic frailty scale of 3 and 4 were defined as high. The primary endpoint was all-cause mortality following TAVR. RESULTS: Seven hundred ninety-six patients who had their facial photographs taken within six months before the TAVR procedure were analyzed. Patients with a higher photographic frailty scale belonged to New York Heart Association classes III/IV, and had higher Society of Thoracic Surgeons scores, higher incidence of wheelchair usage, lower hemoglobin, and smaller aortic valve areas. According to the frailty assessment, patients with a higher photographic frailty scale exhibited slower performance in the 5-m walk test, reduced hand grip strength, more severe dementia, had a higher clinical frailty scale, and lower serum albumin level. Multivariable Cox regression analysis revealed that the high photographic frailty scale was independently associated with all-cause mortality (adjusted hazard ratio 1.62, 95 % confidence interval 1.12-2.33, p = 0.010). Kaplan-Meier analysis indicated that patients with high photographic frailty scale had higher all-cause mortality rates compared to those with low scale (log-rank p = 0.011). CONCLUSIONS: Patient registration photographs can be used to obtain qualitative assessments of frailty in severe aortic stenosis cases, and such assessments can independently predict poor outcomes following TAVR.

A new insight into superacute care for type A acute aortic dissection in the Tokyo Acute Aortic Super Network.

OBJECTIVE: To determine the status of type A acute aortic dissection using the Tokyo Acute Aortic Super Network. METHODS: Data of 6283 patients with acute aortic dissection between 2015 and 2019 were collected. Data of 3303 patients with type A acute aortic dissection were extracted for analysis. RESULTS: Overall, 51.0% of patients were nondirect admissions. On arrival, 23.1% of patients were in shock, 10.0% in cardiopulmonary arrest, and 11.8% in deep coma or coma. Overall, 9.8% of patients were assessed as untreatable. Of 2979 treatable patients, 18.3% underwent medical treatment, whereas 80.7% underwent surgery (open [78.8%], endovascular [1.9%], and peripheral [1.1%] repair). The early mortality rate was 20.5%, including untreatable cases. Among treatable patients, in-hospital mortality rates were 8.6% for open repair, 10.7% for endovascular repair, and 25.3% for medical treatment. Advanced age, preoperative comorbidities, classical dissection, and medical treatment were risk factors for in-hospital mortality. Nondirect admission did not cause increased deaths. The mortality rates were high during the superacute phase following symptom onset. CONCLUSIONS: This study demonstrated current practices in the emergency care of type A acute aortic dissection via the Tokyo Acute Aortic Super Network system, specifically a high rate of untreatable or inoperable cases and favorable outcomes in patients undergoing surgical treatment. High mortality rates were observed during the super acute phase after symptom onset or hospital arrival.

Utility of Cardiac Rehabilitation for Long-Term Outcomes in Patients with Hospital-Acquired Functional Decline after Cardiac Surgery: A Retrospective Study.

Hospital-acquired functional decline is an important outcome that affects the long-term prognosis of patients after cardiac surgery. Phase II cardiac rehabilitation (CR) for outpatients is expected to improve prognosis; however, this is not clear in patients with hospital-acquired functional decline after cardiac surgery. Therefore, this study evaluated whether phase II CR improved the long-term prognosis of patients with hospital-acquired functional decline after cardiac surgery. This single-center, retrospective observational study included 2371 patients who required cardiac surgery. Hospital-acquired functional decline occurred in 377 patients (15.9%) after cardiac surgery. The mean follow-up period was 1219 ± 682 days in all patients, and there were 221 (9.3%) cases with major adverse cardiovascular events (MACE) after discharge during the follow-up period. The Kaplan-Meier survival curves indicated that hospital-acquired functional decline and non-phase II CR was associated with a higher incidence of MACE than other groups (log-rank, p < 0.001), additionally exhibiting prognosticating MACE in multivariate Cox regression analysis (HR, 1.59; 95% CI, 1.01-2.50; p = 0.047). Hospital-acquired functional decline after cardiac surgery and non-phase II CR were risk factors for MACE. The participation in phase II CR in patients with hospital-acquired functional decline after cardiac surgery could reduce the risk of MACE.

Exploring the Frailty Components Related to Hospitalization-Associated Disability in Older Patients After Cardiac Surgery Using a Comprehensive Frailty Assessment.

BACKGROUND: We investigated the components of frailty associated with hospitalization-associated disability (HAD) after cardiac surgery.Methods and Results: This retrospective, observational study evaluated 1,446 older patients after elective cardiac surgery at the Sakakibara Heart Institute. We examined the association between HAD and 7 domains of frailty assessed by the Kihon Checklist. HAD was defined as a decline in the ability to perform activities of daily living (ADL) between admission and discharge, as assessed by the Barthel Index. Logistic regression and decision tree analysis were used to identify associations between the number and type of frailty components and HAD. Of the 1,446 patients, 190 were excluded, and 90 (7%) developed HAD. An increase in the number of frailty components was a risk factor for HAD (odds ratio: 1.88, 95% confidence interval: 1.62-2.17). Decision tree analysis identified physical functional decline, depression, and cognitive dysfunction as factors associated with HAD. The incidence of HAD was highest in cases of physical functional decline (21%) and lowest for cases in which the 3 aforementioned factors were absent (2.8%). CONCLUSIONS: An increased number of frailty factors increased the risk of HAD and the findings also reaffirmed the importance of a comprehensive assessment to evaluate the risk of HAD, including evaluation of physical function, cognitive function, and depression.

A successful case of patch angioplasty with bovine pericardium XenoSure® to the common femoral artery after endarterectomy.

INTRODUCTION AND IMPORTANCE: The number of patients with chronic limb-threatening ischemia has increased in recent years. Herein, we report a rare case of angioplasty with a bovine pericardial patch in a patient with severe stenosis of the common femoral artery. CASE PRESENTATION: We report a case of a 73-year-old female with intermittent claudication. Ankle-brachial index (ABI) measurements showed a significant decrease of 0.52 on the left, and angiography revealed total occlusion on the left common femoral artery (CFA). Considering additional skin incisions, postoperative wound infection, and potential graft sampling, endarterectomy of the left CFA and patch angioplasty with the bovine pericardium (XenoSure®) were performed. The operative computed tomography showed no stenosis and the ABI improved from 0.52 to 1.15. Additionally, no stenosis, calcification, or dilatation was observed during the follow-up one year after the operation. CLINICAL DISCUSSION: Various types of peripheral arterial repair were performed after endarterectomy. Autologous vein grafts and vascular prostheses are frequently used considering the background of each patient. Using bovine pericardium over other devices has several advantages, including no additional skin incisions to obtain the patches, resistance to infection, no oozing from the device itself, less bleeding from the suture site, and ease of hemostasis after the puncture under additional endovascular treatment. This case may be a good implication when deciding which device to use in complicated patients. CONCLUSION: This case provides valuable insight into successful patch angioplasty after endarterectomy without any complications, highlighting the utility of XenoSure® in the treatment of this disease.

Impact of quantitative flow ratio on graft function in patients undergoing coronary artery bypass grafting.

Recent studies showed that preoperative functional assessment with fractional flow reserve (FFR) could predict a long-term patency of arterial bypass grafts in patients with coronary artery bypass grafting (CABG). Quantitative flow ratio (QFR) is a novel angiography-based approach to estimate FFR. This study aimed to investigate whether preoperative QFR could discriminate arterial bypass function at 1 year after surgery. The PRIDE-METAL registry was a prospective, multicenter observational study that enrolled 54 patients with multivessel coronary artery disease. By protocol, left coronary stenoses were revascularized by CABG with arterial grafts, whereas right coronary stenoses were treated with coronary stenting. Follow-up angiography at 1 year after surgery was scheduled to assess arterial graft patency. QFR was performed using index angiography by certified analysts, blinded to bypass graft function. The primary end point of this sub-study was the discriminative ability of QFR for arterial graft function, as assessed by receiver-operating characteristic curve. Among 54 patients enrolled in the PRIDE-METAL registry, index and follow-up angiography was available in 41 patients with 97 anastomoses. QFR were analyzed in 35 patients (71 anastomoses) with an analyzability of 85.5% (71/83). Five bypass grafts were found to be non-functional at 1 year. The diagnostic performance of QFR was substantial (area under the curve: 0.89; 95% confidence interval: 0.83 to 0.96) with an optimal cutoff of 0.76 to predict functionality of bypass grafts. Preoperative QFR is highly discriminative for predicting postoperative arterial graft function.Trial registration: Clinical.gov reference: NCT02894255.

[Clinical Considerations in the Surgical Management of Active Infective Endocarditis of the Mitral Valve].

In the surgical management of infective endocarditis (IE), the presence of circulatory failure from valve destruction and vegetation embolization are important factors in determining the timing of surgery. Emergency surgery carries certain risks, such as infection control problems due to the unknown portal of entry of bacteria and infection, and the possibility of worsening cerebral hemorrhage in patients with hemorrhagic cerebrovascular disease. In recent years, there has been a trend toward more aggressive attempts at mitral valve repair for mitral IE, with improved success rates and rates of recurrent mitral regurgitation, and some reports suggesting that valve repair for active IE has better longterm survival rates than valve replacement. One possible factor is that early surgical intervention to resect the lesion may have a significant impact on the cure rate by preventing progression of valve destruction and controlling infection. Based on our clinical experience, we discuss the optimal timing of surgical intervention for mitral valve IE and present the postoperative remote survival rate, avoidance rate of reinfection, and avoidance rate of reoperation.

1-year outcomes of patients implanted with the Perceval sutureless valve: the Japanese post-marketing surveillance study.

Sutureless offers an alternative to standard valves in surgical aortic valve replacement (SAVR). We sought to confirm the efficacy and safety of the Perceval sutureless valve in Japanese patients. Prospective observational study of 204 patients who underwent SAVR with Perceval at 19 sites in Japan between March and December 2019. The primary outcomes were 30-day mortality and postoperative complications; the secondary outcome was all-cause mortality at 1 year. Efficacy outcomes were changed in New York Heart Association (NYHA) class, pressure gradients, effective orifice area (EOA), EOA indexed to body surface area (EOAi) and severity of aortic regurgitation. Mean age was 77.7 years, 62.7% were female. Procedural success rate was 99.0%. The median cross-clamp and cardiopulmonary bypass times were 68.0 and 108 min. Perceval size S and M were implanted in 95 (46.6%) and in 76 (37.3%) of patients, respectively. The 30-day and late mortality rate were 0.5% and 4.4%, while the new permanent pacemaker implantation rate was 4.4%. Mean pressure gradient was 13.0 mmHg at discharge, reaching 11.0 mmHg at 1 year; while the mean EOA was 1.5 cm2 at discharge remaining stable up to 1 year. No moderate or severe leakages were present at discharge or at 1 year. NYHA class improved by ≥ 1 level in 55.1% of the patients at discharge and in 69.4% of the patients at 1 year. 1-year outcomes of SAVR with the Perceval sutureless valve in Japanese patients were favorable. This valve offers a promising alternative to conventional biological AVR in this Japanese population.

Outcomes of type A acute aortic dissection with cardiopulmonary arrest: Tokyo Acute Aortic Super-network Registry.

OBJECTIVES: Preventing loss of life in patients with type A acute aortic dissection (AAD) who present with cardiopulmonary arrest (CPA) can be extremely difficult. Thus, we investigated the early outcomes in these patients. METHODS: Patients with type A AAD who were transported to hospitals belonging to the Tokyo Acute Aortic Super-network between January 2015 and December 2019 were considered for this study. We assessed the early mortality of these patients presenting with CPA and also investigated the differences in outcomes between patients with out-of-hospital and in-hospital CPA. RESULTS: A total of 3307 patients with type A AAD were transported, 434 (13.1%) of whom presented with CPA. The overall mortality of patients presenting with CPA was 88.2% (383/434), of which 94.5% (240/254) experienced out-of-hospital CPA and 79.4% (143/180) experienced in-hospital CPA (P < 0.001). Multivariable analysis revealed that aortic surgery [odds ratio (OR), 0.022; 95% confidence interval (CI), 0.008-0.060; P < 0.001] and patient age over 80 years (OR, 2.946; 95% CI, 1.012-8.572; P = 0.047) were related with mortality in patients with type A AAD and CPA. Between in-hospital and out-of-hospital CPA, the proportions of DeBakey type 1 (OR, 2.32; 95% CI, 1.065-5.054; P = 0.034), cerebral malperfusion (OR, 0.188; 95% CI, 0.056-0.629; P = 0.007), aortic surgery (OR, 0.111; 95% CI, 0.045-0.271; P = 0.001), age (OR, 0.969; 95% CI, 0.940-0.998; P = 0.039) and the time from symptom onset to hospital admission (OR, 1.122; 95% CI, 1.025-1.228; P = 0.012) were significantly different. CONCLUSIONS: Patients with type A AAD presenting with CPA exhibited extremely high rates of death. Patient outcomes following in-hospital CPA tended to be better than those following out-of-hospital CPA; however, this difference was not significantly different. To prevent deaths, aortic surgery, when possible, should be considered in patients with type A AAD who sustained CPA.

Transcatheter aortic valve replacement-related aortic dissection: A clinical case series.

OBJECTIVES: We review our experience with 13 periprocedural aortic dissection (AD) cases caused by transcatheter aortic valve replacement (TAVR). BACKGROUND: AD is a potentially lethal complication of TAVR; however, only sporadic case reports have been published to date. METHODS: Among 1335 consecutive patients who underwent TAVR in 2013-2021, we retrospectively extracted 13 patients (1.0%) with TAVR-related AD (Stanford type A in 6 [46%], type B in 7 [54%]). AD was defined as a new-onset dissected layer of the aortic wall and diagnosed by aortography, computed tomography, or transesophageal echocardiography. RESULTS: Five of the six type A AD cases (83%) were detected during TAVR versus only one of the seven type B AD cases (14%). Four of the seven type B AD cases (57%) were asymptomatic and incidentally detected on computed tomography. The presumed causes of AD were injury by the delivery sheath (39%), delivery catheter (23%), valve implantation (15%), stent edge (15%), and pre-dilation balloon (8%). Complicated AD occurred in only one patient (8%). Considering the patient's age and prohibitive surgical risk, all patients were treated conservatively and free of any aortic-related deaths or interventions during a follow-up of 1087 days. CONCLUSIONS: TAVR-related AD is a rare but life-threatening condition that may be underdiagnosed. Its optimal therapy remains unclear, and conservative management might be an option for selected patients. Further studies are needed to elucidate the incidence, risk factors, effective screening, optimal therapy, and outcomes of TAVR-related AD.

Surgical aortic valve replacement provides better left ventricular mass regression than transcatheter aortic valve replacement in patients with small aortic annulus.

OBJECTIVES: This study aimed to evaluate the incidence of patient-prosthesis mismatch (PPM) and degree of left ventricular (LV) mass regression after surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) in patients with small aortic annulus (defined as annular diameter of ≤ 21 mm). METHODS: We retrospectively analyzed echocardiographic findings in total of 277 patients with aortic stenosis and small aortic annulus (63 underwent SAVR and 214 underwent TAVR) between October 2013 and March 2019. PPM was defined as an effective orifice area index (EOAI) ≤ 0.85 cm2/m2. LV mass regression was evaluated as percentage change in LV mass index (LVMI) from baseline to the 1-year follow-up. RESULTS: The median EOAI before discharge was slightly larger in the TAVR group than in the SAVR group (1.09 vs. 1.07 cm2/m2; P = 0.030). However, the incidence of PPM before discharge (9.4 vs. 12.7%; P = 0.438) and at the 1-year follow-up (11.7 vs. 11.1%; P = 0.901) was similar between groups. Mild or greater paravalvular leakage (PVL) after the procedure was more frequent in the TAVR group (11.7 vs. 0%; P = 0.002). Reduction in LVMI was significantly higher in the SAVR group (19.3 vs. 6.4%; P < 0.001). Multivariate analysis demonstrated that reduction in LVMI was positively associated with higher baseline transaortic pressure gradient (P < 0.001) and higher baseline LVMI (P < 0.001) and negatively associated with older age (P < 0.001) and mild or greater PVL (P < 0.001). CONCLUSIONS: SAVR provides better LV mass regression than TAVR with a comparable rate of PPM in patients with small aortic annulus.

Efficacy of Early Cardiac Rehabilitation After Cardiac Surgery　- Verification Using Japanese Diagnosis Procedure Combination Data.

Background: The current status of cardiac rehabilitation (CR) after cardiac surgery and the introduction of early CR (E-CR) in Japan are not fully understood. In this study, the current status of E-CR and its efficacy were investigated by the Academic Committee of the Japanese Association of Cardiac Rehabilitation. Methods and Results: We examined the rate of introduction of E-CR and its effects among 220,122 patients who underwent major cardiac and thoracic vascular surgery, as registered in the Diagnosis Procedure Combination (DPC) classification system, between April 2012 and March 2018. In this study, E-CR was defined as CR starting within 1 day after surgery. Patients with and without E-CR were propensity score matched and analyzed for clinical outcomes. Of all patients participating in CR after surgery, E-CR was initiated in 52.1%, 56.9%, 47.4%, and 54.1% of patients undergoing coronary artery bypass grafting, valve surgery, aortic surgery, and other cardiovascular surgery, respectively. After propensity score matching, outcomes for E-CR were significantly superior to non-E-CR in terms of in-hospital deaths, Barthel Index score at discharge, length of hospital stay, and hospitalization costs. Conclusions: E-CR after cardiac surgery was effective in terms of prognosis, hospital stay, and medical costs. This study is the first report using big data in Japan. The results indicate that further introduction of E-CR needs to be recommended in the future.

In-Hospital Mortality of Patients With Acute Type A Aortic Dissection Hospitalized on Weekends Versus Weekdays.

Background: In acute aortic dissection, weekend admissions are reported to be associated with increased mortality compared with weekday admissions. Objective: This study aimed to determine whether patients with acute type A aortic dissection (ATAAD) admitted on weekends had higher in-hospital mortality than those admitted on weekdays in the Tokyo metropolitan area, where we developed a patient-transfer system for aortic dissection. Methods: Data were collected during the first year after our transfer system began (cohort I) and in the subsequent years from 2013 to 2015 (cohort II). Results: We studied 2,339 patients (500 in cohort I; 1,839 in cohort II) with ATAAD. Patients with weekend admissions had higher in-hospital mortality than those with weekday admissions in cohort I. In association with increased interfacility transfer during weekends and reduced mortality at non-high-volume centers, the in-hospital mortality in the weekend group improved from 37.2% in cohort I to 22.2% in cohort II (P < 0.001). After inverse probability weighting adjustment, weekend admission was associated with higher in-hospital mortality in cohort I (odds ratio: 2.28; 95% confidence interval: 1.48 to 3.52; P < 0.001), but not in cohort II (odds ratio: 0.96; 95% confidence interval: 0.75 to 1.22; P = 0.731). On multivariable analyses, weekend admission was associated with higher in-hospital mortality in combined cohort I+II; the associations between weekend admission and mortality were not significant in cohort II. Conclusions: We found a significant reduction in in-hospital mortality in patients with weekend admissions for ATAAD. No mortality difference between weekend and weekday admissions was observed in the later years of the study.