Relationship between 2nd-generation angiotensin receptor blockers and the risk of hypotension in COVID-19 patients admitted to hospital.

It has not yet been established whether angiotensin II receptor blockers (ARB), statins, and multiple drugs affect the severity of COVID-19. Therefore, we herein performed an observational study on the effects of 1st- and 2nd-generation ARB, statins, and multiple drugs, on COVID-19 in patients admitted to 15 Japanese medical facilities. The results obtained showed that ARB, statins, and multiple drugs were not associated with the primary outcome (odds ratio: 1.040, 95% confidence interval: 0.688-0.571; 0.696, 0.439-1.103; 1.056, 0.941-1.185, respectively), each component of the primary outcome (in-hospital death, ventilator support, extracorporeal membrane oxygenation support, and admission to the intensive care unit), or the secondary outcomes (oxygen administration, disturbed consciousness, and hypotension, defined as systolic blood pressure ≤90 mmHg). ARB were divided into 1st- and 2nd-generations based on their approval for use (before 2000 and after 2001), with the former consisting of losartan, candesartan, and valsartan, and the latter of telmisartan, olmesartan, irbesartan, and azilsartan. The difference of ARB generation was not associated with the primary outcome (odds ratio with 2nd-generation ARB relative to 1st-generation ARB: 1.257, 95% confidence interval: 0.613-2.574). The odd ratio for a hypotension as one of the secondary outcomes with 2nd-generation ARB was 1.754 (95% confidence interval: 1.745-1.763) relative to 1st-generation ARB. These results suggest that patients taking 2nd-generation ARB may be at a higher risk of hypotension than those taking 1st-generation ARB and also that careful observations are needed. Further studies are continuously needed to support decisions to adjust medications for co-morbidities.

Usefulness of the Yokohama Advanced Cardiopulmonary Help Team in patients with acute respiratory distress syndrome.

Aim: To evaluate whether establishing an extracorporeal membrane oxygenation (ECMO) specialist team, termed the Yokohama Advanced Cardiopulmonary Help Team (YACHT), affected the outcomes and centralization of patients requiring ECMO in Yokohama-Yokosuka regions. Methods: This retrospective observational study included patients aged ≥18 years and treated with venovenous-ECMO for severe acute respiratory distress syndrome (ARDS) from 2014 to 2023. The primary outcome was intensive care unit (ICU) mortality. The secondary outcomes included ICU-, mechanical ventilator-, and ECMO-free days and complications during the first 28 days. Results: This study included 46 (12 without- and 34 with-YACHT) patients. Among with-YACHT patients, 24 were transferred to our hospital from other hospitals, 14 were assessed by dispatched ECMO physicians, and 9 were transferred after ECMO introduction. No without-YACHT patients were transferred from other hospitals. With-YACHT patients experienced coronavirus disease 2019-associated respiratory failure more frequently (0 vs. 27, p < 0.001) and had higher Acute Physiology and Chronic Health Evaluation II scores (19 vs. 24, p = 0.037) and lower Respiratory Extracorporeal Membrane Oxygenation Survival Prediction scores (4 vs. 2, p = 0.021). ICU mortality was not significantly different between the groups (2 vs. 4, p = 0.67). ICU- (14 vs. 9, p = 0.10), ventilator- (11 vs. 5, p = 0.01), and ECMO-free days (20 vs. 14, p = 0.038) were higher before YACHT establishment. The incidences of complications were not significantly different between the groups. Conclusions: Mortality was not significantly different pre- and post-YACHT establishment; however, it helped promote regionalization and centralization in Yokohama-Yokosuka areas. We will collect more cases to demonstrate YACHT's usefulness.

Clinical characteristics of aneurysmal subarachnoid haemorrhage complicated by Takotsubo cardiomyopathy resulting in good neurological outcome.

BACKGROUND: Takotsubo cardiomyopathy (TC) is a well-known complication of subarachnoid haemorrhage (SAH), often accompanied by neurogenic myocardial dysfunction. Although TC has been reported to be associated with higher morbidity and mortality among patients with aneurysmal SAH (aSAH), some patients have been reported to recover, the profiles and follow-up outcomes of these survivors remain unclear. MATERIALS AND METHODS: To characterize the profiles of patients with aSAH complicated by TC who experienced favourable outcomes using long-term follow-up data, a consecutive series of patients with aSAH were enrolled and TC diagnosis was based on the revised version of the Mayo Clinic criteria. Clinical outcomes were assessed at 6 months according to modified Rankin Scale scores. RESULTS: Among 165 consecutive patients with aSAH, 15 cases were complicated by TC, corresponding to an occurrence rate of 9.0%. Five patients with aSAH complicated by TC (33.3%) experienced a favourable outcome, and the mean value of systolic blood pressure on arrival was significantly lower than in those who experienced an unfavourable outcome (p = 0.032). CONCLUSION: According to analysis, it is possible cardiac dysfunction with decreased cerebral perfusion pressure and catecholamine toxicity transiently worsens conscious disturbance in aSAH complicated by TC. Therefore, it is important to carefully screen patients with aSAH to identify those complicated by TC, and for close collaboration of the multidisciplinary team to design appropriate treatment strategies.

Laparoscopy for emergency abdominal surgery is associated with reduced physical functional decline in older patients: a cohort study.

BACKGROUND: An increasing number of older patients require emergency abdominal surgery for acute abdomen. They are susceptible to surgical stress and lose their independence in performing daily activities. Laparoscopic surgery is associated with faster recovery, less postoperative pain, and shorter hospital stay. However, few studies have examined the relationship between laparoscopic surgery and physical functional decline. Thus, we aimed to examine the relationship between changes in physical function and the surgical procedure. METHODS: In this was a single-center, retrospective cohort study, we enrolled patients who were aged ≥ 65 years and underwent emergency abdominal surgery for acute abdomen between January 1, 2019, and December 31, 2021. We assessed their activities of daily living using the Barthel Index. Functional decline was defined as a decrease of ≥ 20 points in Barthel Index at 28 days postoperatively, compared with the preoperative value. We evaluated an association between functional decline and surgical procedures among older patients, using multiple logistic regression analysis. RESULTS: During the study period, 852 patients underwent emergency abdominal surgery. Among these, 280 patients were eligible for the analysis. Among them, 94 underwent laparoscopic surgery, while 186 underwent open surgery. Patients who underwent laparoscopic surgery showed a less functional decline at 28 days postoperatively (6 vs. 49, p < 0.001). After adjustments for other covariates, laparoscopic surgery was an independent preventive factor for postoperative functional decline (OR, 0.22; 95% CI, 0.05-0.83; p < 0.05). CONCLUSIONS: In emergency abdominal surgery, laparoscopic surgery reduces postoperative physical functional decline in older patients. Widespread use of laparoscopic surgery can potentially preserve patient quality of life and may be important for the better development of emergency abdominal surgery.

Transcriptome analysis reveals limited toxic effects of the UV-filter benzophenone-3 (BP-3) on the hermatypic coral Acropora tenuis and its symbiotic dinoflagellates.

This study aimed to investigate the toxic and transcriptomic effects of the ultraviolet filter benzophenone-3 (BP-3) on Acropora tenuis and its symbiotic dinoflagellates while using acetone as a solvent. Seven-day exposure to 50 and 500 µg/L, which is higher than most BP-3 records from coastal waters, did not affect coral colour or dinoflagellate photosynthesis. Differentially expressed genes (DEGs) between seawater and solvent controls were <20 in both corals and dinoflagellates. Eleven coral DEGs were detected after treatment with 50 µg/L BP-3. Fourteen coral DEGs, including several fluorescent protein genes, were detected after treatment with 500 µg/L BP-3. In contrast, no dinoflagellate DEGs were detected in the BP-3 treatment group. These results suggest that the effects of 50-500 µg/L BP-3 on adult A. tenuis and its dinoflagellates are limited. Our experimental methods with lower acetone toxicity provide a basis for establishing standard ecotoxicity tests for corals.

Multimodal Gated Mixture of Experts Using Whole Slide Image and Flow Cytometry for Multiple Instance Learning Classification of Lymphoma.

In this study, we present a deep-learning-based multimodal classification method for lymphoma diagnosis in digital pathology, which utilizes a whole slide image (WSI) as the primary image data and flow cytometry (FCM) data as auxiliary information. In pathological diagnosis of malignant lymphoma, FCM serves as valuable auxiliary information during the diagnosis process, offering useful insights into predicting the major class (superclass) of subtypes. By incorporating both images and FCM data into the classification process, we can develop a method that mimics the diagnostic process of pathologists, enhancing the explainability. In order to incorporate the hierarchical structure between superclasses and their subclasses, the proposed method utilizes a network structure that effectively combines the mixture of experts (MoE) and multiple instance learning (MIL) techniques, where MIL is widely recognized for its effectiveness in handling WSIs in digital pathology. The MoE network in the proposed method consists of a gating network for superclass classification and multiple expert networks for (sub)class classification, specialized for each superclass. To evaluate the effectiveness of our method, we conducted experiments involving a six-class classification task using 600 lymphoma cases. The proposed method achieved a classification accuracy of 72.3%, surpassing the 69.5% obtained through the straightforward combination of FCM and images, as well as the 70.2% achieved by the method using only images. Moreover, the combination of multiple weights in the MoE and MIL allows for the visualization of specific cellular and tumor regions, resulting in a highly explanatory model that cannot be attained with conventional methods. It is anticipated that by targeting a larger number of classes and increasing the number of expert networks, the proposed method could be effectively applied to the real problem of lymphoma diagnosis.

Appropriate Endotracheal Tube Position for Percutaneous Dilatational Tracheostomy: A Single-Center Observational Study.

Aim This study aimed to investigate the appropriate endotracheal tube (ETT) position during percutaneous dilatational tracheostomy (PDT). Methods This single-center observational study included hospitalized patients who underwent surgical tracheostomy (ST) between August 2021 and October 2022. During ST, the trachea was opened, and the ETT was pulled out visually. It stopped when the ETT was no longer visible, and the tracheostomy tube was placed in the trachea. The ETT position was measured by considering the ETT position during ST to be the appropriate position during PDT. The correlation between the measured ETT position and patient characteristics was evaluated. A prediction equation for the ETT position was derived from the derivation group, and validation of the prediction equation was evaluated by the validation group. Results Forty-six and 15 patients were in the derivation and validation groups, respectively. Weight, duration of intubation, and in-hospital mortality were significantly different between the two groups. The measured ETT position correlated with body height (r=0.60, p<0.001) and sex (r=0.45, p=0.002), while the ETT position before ST showed a weak correlation (r=0.34, p=0.020). The predicted and measured values in the validation group correlated with each other (r=0.58, p=0.024). Conclusion The appropriate ETT position for PDT correlates with body height, and the equation "body height×0.112-0.323 cm" was derived. This predictive equation may be useful as a guide for ETT positioning during PDT puncture.

The Examination of Prognostic Factors and Treatment Strategies for Traumatic Cerebrospinal Fluid Leakage.

Introduction This study aimed to determine the optimal timing for surgical intervention and the prognostic factors of cerebrospinal fluid (CSF) leakage. Methods We identified 25 patients with probable CSF leaks from 472 consecutive patients with head trauma. In addition to baseline characteristics and findings on admission, injury severity score (ISS), abbreviated injury score (AIS), and other factors related to CSF leakage were considered. We analyzed the prognostic factors after setting the primary endpoint as the modified Rankin Scale (mRS) at the time of discharge to determine the appropriate timing for surgical intervention. Results Univariate analysis revealed significantly poorer prognoses for elderly patients (p<0.001) and cases with low Glasgow Coma Scale (GCS) levels (p=0.039) and high D-dimer levels (p=0.028), which was consistent with findings from the analyses of all patients with head trauma. We found that multiple traumas (AIS≥3 at two or more sites, p=0.047) and high lactate levels (p=0.043) were poor prognostic factors specific to CSF leakage cases, while a longer time to CSF leakage cessation was also associated with a poorer prognosis (median, six days versus 13 days, p=0.014). An evaluation of the time to closure found that spontaneous cessation occurred within 14 days in most cases. Conclusions Conservative medical treatment is the first choice for most cases of traumatic CSF leakage. Surgical intervention should be considered if leakage does not cease after 14 days post injury. Furthermore, severe multiple injuries and high lactate levels were poor prognostic factors specific to patients with CSF leakage.

Prophylactic distal perfusion catheter and survival in patients with out-of-hospital cardiac arrest: Secondary analysis of the SAVE-J II study.

PURPOSE: The effect of a prophylactic distal perfusion catheter (DPC) after extracorporeal cardiopulmonary resuscitation (ECPR) in patients with out-of-hospital cardiac arrest (OHCA) remains unclear. Therefore, we aimed to clarify the association between prophylactic DPC and prognosis in patients with OHCA undergoing ECPR. MATERIALS AND METHODS: A secondary analysis of the Study of Advanced Life Support for Ventricular Fibrillation with Extracorporeal Circulation in Japan (SAVE-J II) database was performed to compare groups of patients with and without prophylactic DPCs. A multivariate analysis of survival at discharge was performed using factors that were significant in the two-arm comparison. RESULTS: A total of 2044 patients were included in the analysis after excluding those who met the exclusion criteria. Survival at discharge was observed in 548 (26.9%) patients. In total, 100 (4.9%) patients developed limb ischemia, among whom 14 (0.7%) required therapeutic intervention. Multivariate analysis showed that prophylactic DPC did not result in a significant difference in survival at discharge (odds ratio: 0.898 [0.652-1.236], p = 0.509). CONCLUSIONS: The implementation of prophylactic DPC after ECPR for patients with OHCA may not contribute to survival at discharge.

Freeform direct-write and rewritable photonic integrated circuits in phase-change thin films.

Photonic integrated circuits (PICs) with rapid prototyping and reprogramming capabilities promise revolutionary impacts on a plethora of photonic technologies. We report direct-write and rewritable photonic circuits on a low-loss phase-change material (PCM) thin film. Complete end-to-end PICs are directly laser-written in one step without additional fabrication processes, and any part of the circuit can be erased and rewritten, facilitating rapid design modification. We demonstrate the versatility of this technique for diverse applications, including an optical interconnect fabric for reconfigurable networking, a photonic crossbar array for optical computing, and a tunable optical filter for optical signal processing. By combining the programmability of the direct laser writing technique with PCM, our technique unlocks opportunities for programmable photonic networking, computing, and signal processing. Moreover, the rewritable photonic circuits enable rapid prototyping and testing in a convenient and cost-efficient manner, eliminate the need for nanofabrication facilities, and thus promote the proliferation of photonics research and education to a broader community.

Novel nanocomposite-superlattices for low energy and high stability nanoscale phase-change memory.

Data-centric applications are pushing the limits of energy-efficiency in today's computing systems, including those based on phase-change memory (PCM). This technology must achieve low-power and stable operation at nanoscale dimensions to succeed in high-density memory arrays. Here we use a novel combination of phase-change material superlattices and nanocomposites (based on Ge4Sb6Te7), to achieve record-low power density ≈ 5 MW/cm2 and ≈ 0.7 V switching voltage (compatible with modern logic processors) in PCM devices with the smallest dimensions to date (≈ 40 nm) for a superlattice technology on a CMOS-compatible substrate. These devices also simultaneously exhibit low resistance drift with 8 resistance states, good endurance (≈ 2 × 108 cycles), and fast switching (≈ 40 ns). The efficient switching is enabled by strong heat confinement within the superlattice materials and the nanoscale device dimensions. The microstructural properties of the Ge4Sb6Te7 nanocomposite and its high crystallization temperature ensure the fast-switching speed and stability in our superlattice PCM devices. These results re-establish PCM technology as one of the frontrunners for energy-efficient data storage and computing.

Congenital anaemia associated with loss-of-function variants in DNA polymerase epsilon 1.

DNA polymerase epsilon (Pol ε), a component of the core replisome, is involved in DNA replication. Although genetic defects of Pol ε have been reported to cause immunodeficiency syndromes, its role in haematopoiesis remains unknown. Here, we identified compound heterozygous variants (p.[Asp1131fs];[Thr1891del]) in POLE, encoding Pol ε catalytic subunit A (POLE1), in siblings with a syndromic form of severe congenital transfusion-dependent anaemia. In contrast to Diamond-Blackfan anaemia, marked reticulocytopenia or marked erythroid hypoplasia was not found. Their bone marrow aspirates during infancy revealed erythroid dysplasia with strongly positive TP53 in immunostaining. Repetitive examinations demonstrated trilineage myelodysplasia within 2 years from birth. They had short stature and facial dysmorphism. HEK293 cell-based expression experiments and analyses of patient-derived induced pluripotent stem cells (iPSCs) disclosed a reduced mRNA level of Asp1131fs-POLE1 and defective nuclear translocation of Thr1891del-POLE1. Analysis of iPSCs showed compensatory mRNA upregulation of the other replisome components and increase of the TP53 protein, both suggesting dysfunction of the replisome. We created Pole-knockout medaka fish and found that heterozygous fishes were viable, but with decreased RBCs. Our observations expand the phenotypic spectrum of the Pol ε defect in humans, additionally providing unique evidence linking Pol ε to haematopoiesis.

The Detection of Neoplastic Cells Using Objective Cytomorphologic Parameters in Malignant Lymphoma.

Pathologic evaluation is the most crucial method for diagnosing malignant lymphomas. However, there are no established diagnostic criteria for evaluating pathologic morphology. We manually circled cell nuclei in the lesions of 10 patients with diffuse large B-cell lymphoma (DLBCL), follicular lymphoma, and reactive lymphadenitis. Seventeen parameters related to nuclear shape, color, and other characteristics were measured. We attempted to compare the statistical differences between these subtypes and extract distinctive disease-specific populations on the basis of these parameters. Statistically significant differences were observed between the different types of lymphoma for many of the 17 parameters. Through t-distributed stochastic neighbor embedding analysis, we extracted a cluster of cells that showed distinctive features of DLBCL and were not found in follicular lymphoma or reactive lymphadenitis. We created a decision tree to identify the characteristics of the cells within that cluster. Based on a 5-fold cross-validation study, the average sensitivity, specificity, and accuracy obtained were 84.1%, 98.4%, and 97.3%, respectively. A similar result was achieved using a validation experiment. Important parameters that indicate the features of DLBCL include Area, ConcaveCount, MaxGray, and ModeGray. By quantifying pathologic morphology, it was possible to objectively represent the cell morphology specific to each lymphoma subtype using quantitative indicators. The quantified morphologic information has the potential to serve as a reproducible and flexible diagnostic tool.

Efficient model selection for predictive pattern mining model by safe pattern pruning.

Predictive pattern mining is an approach used to construct prediction models when the input is represented by structured data, such as sets, graphs, and sequences. The main idea behind predictive pattern mining is to build a prediction model by considering unified inconsistent notation sub-structures, such as subsets, subgraphs, and subsequences (referred to as patterns), present in the structured data as features of the model. The primary challenge in predictive pattern mining lies in the exponential growth of the number of patterns with the complexity of the structured data. In this study, we propose the safe pattern pruning method to address the explosion of pattern numbers in predictive pattern mining. We also discuss how it can be effectively employed throughout the entire model building process in practical data analysis. To demonstrate the effectiveness of the proposed method, we conduct numerical experiments on regression and classification problems involving sets, graphs, and sequences.

Out-of-hospital cardiac arrest patients during the coronavirus disease 2019 pandemic.

The coronavirus disease 2019 (COVID-19) pandemic had severe impact on the outcome of out-of-hospital cardiac arrest (OHCA) patients and the possibility of bystander cardiopulmonary resuscitation (CPR). Previous studies focused only on the short periods of the pandemic and reported a significant increase in the number of infections. In a retrospective cohort study we aimed to compare the outcomes of OHCA patients 1 year before and 1 year after the onset of COVID-19. Data of 519 OHCA patients during the pre-pandemic (January-December 2019; 262 patients) and intra-pandemic (April 2020-March 2021; 257 patients) periods in Yokohama Municipal Hospital, Japan were collected and analysed retrospectively. The study outcomes were the return of spontaneous circulation (ROSC), admission to hospital, survival to discharge, and cerebral performance category at discharge. The intra-pandemic period was associated with decreased bystander CPR (P = 0.004), prolonged transport time (P < 0.001), delayed first adrenaline administration (P < 0.001), and decrease in ROSC (P = 0.023). Logistic regression analysis revealed that the following factors were significantly associated with ROSC: "pandemic", "shockable initial waveform", and "witness presence".

Combining blood glucose and SpO2/FiO2 ratio facilitates prediction of imminent ventilatory needs in emergency room COVID-19 patients.

The increasing requirement of mechanical ventilation (MV) due to the novel coronavirus disease (COVID-19) is still a global threat. The aim of this study is to identify markers that can easily stratify the impending use of MV in the emergency room (ER). A total of 106 patients with COVID-19 requiring oxygen support were enrolled. Fifty-nine patients were provided MV 0.5 h (interquartile range: 0.3 to 1.4) post-admission. Clinical and laboratory data before intubation were collected. Using a multivariate logistic regression model, we identified four markers associated with the impending use of MV, including the ratio of peripheral blood oxygen saturation to fraction of inspired oxygen (SpO2/FiO2 ratio), alanine aminotransferase, blood glucose (BG), and lymphocyte counts. Among these markers, SpO2/FiO2 ratio and BG, which can be measured easily and immediately, showed higher accuracy (AUC: 0.88) than SpO2/FiO2 ratio alone (AUC: 0.84), despite no significant difference (DeLong test: P = 0.591). Moreover, even in patients without severe respiratory failure (SpO2/FiO2 ratio > 300), BG (> 138 mg/dL) was predictive of MV use. Measuring BG and SpO2/FiO2 ratio may be a simple and versatile new strategy to accurately identify ER patients with COVID-19 at high risk for the imminent need of MV.

Deep learning based identification of pituitary adenoma on surgical endoscopic images: a pilot study.

Accurate tumor identification during surgical excision is necessary for neurosurgeons to determine the extent of resection without damaging the surrounding tissues. No conventional technologies have achieved reliable performance for pituitary adenomas. This study proposes a deep learning approach using intraoperative endoscopic images to discriminate pituitary adenomas from non-tumorous tissue inside the sella turcica. Static images were extracted from 50 intraoperative videos of patients with pituitary adenomas. All patients underwent endoscopic transsphenoidal surgery with a 4 K ultrahigh-definition endoscope. The tumor and non-tumorous tissue within the sella turcica were delineated on static images. Using intraoperative images, we developed and validated deep learning models to identify tumorous tissue. Model performance was evaluated using a fivefold per-patient methodology. As a proof-of-concept, the model's predictions were pathologically cross-referenced with a medical professional's diagnosis using the intraoperative images of a prospectively enrolled patient. In total, 605 static images were obtained. Among the cropped 117,223 patches, 58,088 were labeled as tumors, while the remaining 59,135 were labeled as non-tumorous tissues. The evaluation of the image dataset revealed that the wide-ResNet model had the highest accuracy of 0.768, with an F1 score of 0.766. A preliminary evaluation on one patient indicated alignment between the ground truth set by neurosurgeons, the model's predictions, and histopathological findings. Our deep learning algorithm has a positive tumor discrimination performance in intraoperative 4-K endoscopic images in patients with pituitary adenomas.

Effectiveness of call system implementation for postpartum hemorrhage in a tertiary emergency medical center: a retrospective cohort study.

BACKGROUND: Postpartum hemorrhage is the leading cause of maternal death and severe maternal morbidity worldwide. Previous studies have reported the importance of multidisciplinary treatment approaches for postpartum hemorrhage; however, only a few studies have shown a clear improvement in maternal outcomes. Therefore, this study aimed to investigate the efficacy of a call system for postpartum hemorrhage in a tertiary emergency facility for rapid multidisciplinary treatment and its effect on maternal outcomes. METHODS: This single-center retrospective cohort study included patients transferred to our hospital due to postpartum hemorrhage between April 1, 2013, and March 31, 2019. The primary outcome was mortality, and the secondary outcomes were morbidity (duration of hospital stay, duration of intensive care unit stay, admission to the intensive care unit, respirator use, duration of ventilator support, acute kidney injury, transfusion-associated circulatory overload/transfusion-related acute lung injury, hysterectomy, composite adverse events, blood transfusion initiation time, blood transfusion volume, and treatment for postpartum hemorrhage). An in-hospital call system implementation commenced on April 1, 2016. The study outcomes were compared 3 years before and after implementing the call system. RESULTS: The blood transfusion initiation time and duration of hospital stay were significantly shortened after implementing the call system for postpartum hemorrhage. No maternal deaths were observed after implementing the system. CONCLUSIONS: Implementing call systems specialized for postpartum hemorrhage in tertiary emergency facilities may improve maternal outcomes.

Clinical Usefulness of Echocardiographic Measurement of Proximal Aortic Diameter in Early Differentiation Between Type A Acute Aortic Dissection and ST-Segment-Elevation Myocardial Infarction.

Background Contradictions between management modalities of type A acute aortic dissection (TAAAD) and ST-elevation-myocardial infarction (STEMI) may result in clinical catastrophe. Therefore, we aimed to explore which 2-dimensional echocardiography (2DE) findings are optimal for differentiating TAAAD from STEMI. Methods and Results This study included 340 patients with STEMI and 340 patients with TAAAD who underwent 2DE in the emergency department between 2012 and 2021. The proximal ascending aorta (PAA) diameter and other echocardiographic parameters were analyzed. PAA diameters were measured at 4 levels in the parasternal view: Valsalva, the sinotubular junction (STJ), the PAA at 1 cm above the STJ, and the PAA at 2 cm above the STJ. Receiver-operating characteristic curve analysis showed that Valsalva, STJ, PAA at 1 cm above the STJ, and PAA at 2 cm above the STJ were significant predictors of TAAAD (areas under the curve: 0.777, 0.924, 0.965, and 0.975, respectively; P<0.001) with the respective cutoff values of 39.4, 38.5, 39.8, and 41.2 mm. Multivariable analysis suggested that all 2DE parameters were significant predictors of TAAAD. Among the 2DE parameters examined, the incorporation of PAA at 2 cm above the STJ to clinical indicators exhibited the most significant diagnostic capability (C-statistics, 0.97; net reclassification improvement, 1.81; integrated discrimination improvement, 0.61). When only TAAAD with coronary malperfusion and STEMI were analyzed, the diagnostic utility of PAA at 1 cm above the STJ was evident (C-statistics, 0.99; net reclassification improvement, 1.79; integrated discrimination improvement, 0.67), with PAA at 2 cm above the STJ ranking second in diagnostic significance (C-statistics, 0.99; net reclassification improvement, 1.12; integrated discrimination improvement, 0.66). Conclusions PAA measurements were the most beneficial for diagnosing TAAAD in all 2DE findings and TAAAD from STEMI.