Echocardiography
All patients underwent a clinically indicated 2D echocardiogram during their admission according to published guidelines [7]. Standard echocardiographic images in the parasternal, apical, and subcostal views in the left lateral decubitus position were obtained by experienced echocardiography technologists. RAVI was measured using the single plane disc summation method in the four-chamber view, while LAVI was measured using the biplane disc summation method in the four and two-chamber views [7] (Figure 1). All studies were performed using the Philips IE33 or Epiq 7CV (Philips Medical Systems, Andover, MA) or GE Vivid E9 Ultrasound (GE, Milwaukee, WI) systems and were analyzed and processed using Enterprise Imaging (Agfa Healthcare N.V., Mortsel, Belgium). Echocardiographic analyses were performed by two independent investigators who were blinded to clinical outcomes.