Worme MD, et al. - In this study involving patients from the Global Registry of Acute Coronary Events (GRACE) electrocardiogram (ECG) core laboratory substudy who presented with an acute coronary syndrome (ACS), researchers investigated the risk of short- and mid-term cardiovascular (CV) events, death or a composite related to prior atrial fibrillation (AF) or AF presenting or developing during their ACS hospitalization. They found a similar risk of death and major adverse CV events (MACE) following ACS in patients with new-onset and prior AF. They also found that compared to patients without AF, patients with new-onset and prior AF had significantly increased risk of death and MACE following ACS.