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Federated learning (FL) is a method used for training artificial intelligence models with data from multiple sources while maintaining data anonymity, thus removing many barriers to data sharing. Here we used data from 20 institutes across the globe to train a FL model, called EXAM (electronic medical record (EMR) chest X-ray AI model), that predicts the future oxygen requirements of symptomatic patients with COVID-19 using inputs of vital signs, laboratory data and chest X-rays. EXAM achieved an average area under the curve (AUC) >0.92 for predicting outcomes at 24 and 72 h from the time of initial presentation to the emergency room, and it provided 16% improvement in average AUC measured across all participating sites and an average increase in generalizability of 38% when compared with models trained at a single site using that site's data. For prediction of mechanical ventilation treatment or death at 24 h at the largest independent test site, EXAM achieved a sensitivity of 0.950 and specificity of 0.882. In this study, FL facilitated rapid data science collaboration without data exchange and generated a model that generalized across heterogeneous, unharmonized datasets for prediction of clinical outcomes in patients with COVID-19, setting the stage for the broader use of FL in healthcare.

BACKGROUND: Patients with cardiogenic shock have a high risk of mortality. Intravenous levosimendan can provide pharmacologic inotrope support. OBJECTIVES: We aimed to investigate the effect of levosimendan in patients with extremely severe cardiogenic shock and low Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) score with or without mechanical circulatory support. METHODS: From January 2017 to May 2019, 24 patients with INTERMACS 1-4 were enrolled in this retrospective study. All patients had systemic malperfusion and were treated with levosimendan. Biochemistry data related to systemic perfusion were recorded and compared before and at 24 and 72 hours after levosimendan administration. Echocardiography and Kansas City Cardiomyopathy Questionnaire (KCCQ) were completed 2 months later to assess left ventricular ejection fraction (LVEF) and quality of life (QoL), respectively. RESULTS: Arterial pressure and heart rate did not significantly differ before and after levosimendan administration. Atrial fibrillation and ventricular premature complex increased without significance. The dose of inotropes could be significantly tapered down. There were no significant differences in blood urea nitrogen, creatinine, and lactate levels. Urine output significantly increased (p = 0.018), and liver-related enzymes improved but without significance. B-type natriuretic peptide significantly decreased (p = 0.007) at 24 hours after levosimendan administration. Echocardiography showed significantly improved LVEF 2 months later (22.43 ± 8.13% to 35.87 ± 13.4%, p = 0.001). KCCQ showed significantly improved physical activity and greater relief of symptoms (p = 0.003). The survival-to-discharge rate was 75%. CONCLUSIONS: We observed a decrease in B-type natriuretic peptide, better urine output, and alleviated hepatic injury in the levosimendan group. Most patients who survived without transplantation had significantly improved LVEF and better QoL after levosimendan administration.

Inhalation anesthetics provide myocardial protection for cardiac surgery. This study was undertaken to compare the perioperative effects between isoflurane and fentanyl-midazolam-based anesthesia for heart transplantation. A retrospective cohort study was conducted by reviewing the medical records of heart transplantation in a single medical center from 1990 to 2013. Patients receiving isoflurane or fentanyl-midazolam-based anesthesia were included. Those with preoperative severe pulmonary, hepatic, or renal comorbidities were excluded. The perioperative variables and postoperative short-term outcomes were analyzed, including blood glucose levels, urine output, inotropic use, time to extubation, and length of stay in the intensive care units. After reviewing 112 heart transplantations, 18 recipients with fentanyl-midazolam-based anesthesia, and 29 receiving isoflurane anesthesia with minimal low-flow technique were analyzed. After cessation of cardiopulmonary bypass, recipients with isoflurane anesthesia had a significantly lower mean level and a less increase of blood glucose, as compared with those receiving fentanyl-based anesthesia. In addition, there was less use of dobutamine upon arriving the intensive care unit and a shorter time to extubation after isoflurane anesthesia. Compared with fentanyl-midazolam-based anesthesia, isoflurane minimal low-flow anesthesia maintained better perioperative homeostasis of blood glucose levels, less postoperative use of inotropics, and early extubation time among heart-transplant recipients without severe comorbidities.

Atrial fibrillation is the most common complication of cardiac surgery and is associated with significant morbidity and mortality. Recognizing patients at high risk for developing postoperative atrial fibrillation (POAF) may help identify those who could benefit from strategies to prevent POAF. This study was conducted to delineate outcomes and to assess risk factors for POAF among Taiwanese patients undergoing coronary artery bypass grafting (CABG).From January 2009 until February 2012, this prospective study included 266 consecutive patients admitted to our hospital with coronary artery disease. All patients underwent isolated CABG. Patients with preoperative permanent atrial fibrillation and concomitant surgery were excluded. Multiple risk factors associated with the incidence of POAF were collected and evaluated.POAF occurred in 126 of 226 patients (47.37%). Univariate analysis revealed that significant risk factors for the condition were age, gender, diabetes, dyslipidemia, smoking, impaired renal function, impaired cardiac function, and increased serum electrolytes. Multivariate analysis showed dyslipidemia [hazard ratio (HR): 0.418; 95% confidence interval (Cl): 0.190-0.915, p = 0.029], impaired renal function as indicated by an estimated glomerular filtration rate60 mL/min/1.73 m(2) (HR: 3.174; 95% CI: 1.432-7.037, p = 0.004), and serum sodium (HR: 1.112; 95% Cl: 1.047-1.182, p = 0.001) prior to cardiopulmonary bypass as significant. Moreover, POAF was associated with lower 30-day, 1- and 3-year cumulative survival rates and higher early postoperative complications.Patients with isolated CABG who were administered β-blockers, angiotensin converting enzyme inhibitor/angiotensin receptor blockers treatment, and lipid therapy before CABG were associated with reduced POAF, while those with impaired renal function and higher serum sodium before CABG predisposed POAF in a Taiwanese population.Atrial fibrillation (AF); Coronary artery bypass grafting (CABG); Coronary artery disease (CAD); Postoperative atrial fibrillation (POAF).

A 61-year-old male presented to our emergency room with chest tightness, dyspnea, and cold sweat. He underwent a 12-lead EKG which showed ST-elevation from leads V1-V4 and T wave inversion in leads II, III, and aVF. His troponin-I level was elevated to 70.3 ng/ml. He went into cardiogenic shock when he was in the catheter room. After advanced cardiac life support was administered for 30 min, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) cannulation was set up using 21-french arterial and 21-french venous cannula through the right femoral artery and right femoral vein by the puncture method for hemodynamic support. Subsequently, a coronary artery bypass graft (CABG) for acute myocardial infarction was performed. However, the patient was unable to be weaned from the VA-ECMO. Four days later, a CentriMag (Levitronix LLC, Waltham, MA, USA) left ventricular assist device (LVAD) was applied to avoid ECMO-related complications such as severe hemolysis, ischemic, deteriorated liver and renal function. The patient subsequently underwent a successful orthotopic heart transplant after 87 days on the CentriMag LVAD. The patient was extubated on the next postoperative day and was discharged 2 weeks later.

The tyrosine kinase receptor Axl is expressed in the vasculature, and growth arrest-specific protein 6 (Gas6) is its ligand. Plasma Gas6 levels have been shown to be associated with endothelial dysfunction markers and cardiovascular events. We set out to determine the plasma Gas6 levels in patients undergoing coronary artery bypass grafting (CABG) and investigate the expression of Gas6 and Axl in the aorta.Immunoassays were used to investigate plasma Gas6 levels in CABG patients (n = 19) and control subjects (n = 20). The expression of Gas6 and Axl in the injured aorta were examined by reverse transcription-polymerase chain reactions, real-time reverse transcription-polymerase chain reactions, western blotting, and immunohistochemical staining. Plasma Gas6 levels were significantly lower in CABG patients than in matched control subjects. In CABG patients, plasma Gas6 levels were negatively correlated with fasting glucose, E-selectin, and vascular cell adhesion molecule-1 levels. The levels predicted the operative mortality rate and were positively correlated with plasma soluble Axl (sAxl) levels and Gas6 expression in the aorta. Moreover, Gas6 expression was positively correlated with Axl expression in the aorta.We concluded that plasma Gas6 is associated with fasting glucose, endothelial dysfunction markers, sAxl values, and vascular Gas6 expression in CABG patients, and it predicts the operative mortality of these patients. These findings suggest that the Gas6/Axl system is crucial in vascular biology.

We herein describe the case of a 21-year-old woman with Stewart-Bluefarb syndrome presenting with recurrent ulcers on the right foot and multiple congenital arteriovenous malformations. The painful recurrent ulcers and brownish macules at the dorsum of the right foot had appeared at 13 years of age, and the size of the right foot gradually became larger than the left. She underwent conservative treatment and polyvinyl alcohol embolization but the ulcer was recurrent. Two macroscopic detectable feeding arteries to arteriovenous fistulas were ligated under Doppler sonography. At her 6 month follow-up, the chronic ulcer had begun to heal and pain had been alleviated.

Cardiac hemangiomas are extremely rare, and account for 5-10% of benign cardiac tumors. Most clinical presentations involve patient dyspnea on exertion and arrhythmia; asymptomatic patients are uncommon. A 45-year-old man had an asymptomatic left ventricular mass that was found incidentally during an echocardiogram. Magnetic resonance images showed an isointense protruding mass attached to the lateral wall of the left ventricle. The patient underwent a complete surgical resection with a good outcome. Histopathological examination revealed a cavernous hemangioma. The natural course of cardiac hemangiomas varies, and total resection is the favored treatment.