RT Book, Section A1 Pineda, Andres M. A1 Sommer, Robert J. A1 Rhodes III, John F. A1 Beohar, Nirat A2 Baliga, R. R. A2 Lilly, Scott M. A2 Abraham, William T. SR Print(0) ID 1160207394 T1 Defects of the Atrial Septum T2 Color Atlas and Synopsis of Interventional Cardiology YR 2018 FD 2018 PB McGraw-Hill Education PP New York, NY SN 9780071749350 LK accesscardiology.mhmedical.com/content.aspx?aid=1160207394 RD 2022/08/19 AB A 34-year-old woman was seen in the outpatient clinic for a 1-year history of worsening dyspnea on exertion (New York Heart Association class III), 2-pillow orthopnea, bilateral pedal edema, and occasional episodes of palpitations. Her transthoracic echocardiogram revealed an ostium secundum atrial septal defect (ASD), significant enlargement of the right ventricle, evidence of left-­to-right shunt with a pulmonary to systemic flow (Qp/Qs) ratio of 2.3, and normal left ventricular ejection fraction (Figure 26-1). Transesophageal echocardiogram confirmed an ostium secundum ASD of 18-mm diameter with sufficient tissue rims and ruled out additional congenital defects (Figure 26-2). She underwent successful percutaneous closure of her ostium secundum ASD with a 22-mm atrial septal occluder device using intracardiac echocardiography guidance. After 6 months, she remains asymptomatic and a repeat transthoracic echocardiogram revealed no residual shunt across the interatrial septum and significant reduction in right ­ventricular volume.