We present a case report of a 29-year-old pregnant woman at 30 weeks' gestation who presents to the emergency department with 2 weeks of progressive dyspnea on exertion and orthopnea. She assumes her symptoms are related to pregnancy. Her chest radiograph shows cardiomegaly and pulmonary edema, and her laboratory workup reveals a markedly elevated brain natriuretic peptide level. This case highlights a serious etiology of dyspnea in pregnancy that is often delayed in diagnosis. (c) 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.