Thein PM, Ong J, Crozier TM, et al. - In hospitalized adult patients with new-onset atrial fibrillation (AF), researchers described the features, management and outcomes. They used the medical emergency team (MET) database to find patients who had a “MET call” activated for tachycardia between 2015 and 2016. Excluded were patients with sinus tachycardia, pre-existing AF/atrial flutter or other known tachyarrhythmia. In 137 patients (mean age was 74 ± 11.6 years), new-onset AF was found. In hospitalized patients with new-onset AF, left ventricular systolic dysfunction is correlated with increased all-cause mortality, while lower serum potassium levels are related to increased length of stay. Among 79 patients who underwent echocardiography, 80% had left atrial dilatation and 14% had reduced left ventricular ejection fraction (LVEF). Patients with heart failure with reduced LVEF had 7.4 times higher odds of death during acute hospitalization was, as seen in multivariable analysis. In-hospital mortality rate was 11%.