Abstract
Unicuspid aortic valves (UAVs) are rare congenital anomalies associated with severe aortic stenosis (AS) in infancy or later adulthood. This is a case of a 22-year-old woman who presented with acute hypoxemic respiratory failure, which was initially attributed to multilobular pneumonia with acute respiratory distress syndrome. However, echocardiography revealed UAV with severe stenosis, suggesting cardiogenic pulmonary edema. The patient underwent successful surgical aortic valve replacement. This case highlights that the diagnosis and management of UAVs is tenuous: cases are prone to rapid decompensation, such as flash pulmonary edema, with acute hemodynamic changes, such as aggressive intravenous fluid administration. There currently exist no guidelines specific to UAVs, but diagnosis and management can be extrapolated from bicuspid aortic valves presenting with severe stenosis. Congenital valvulopathies should be considered in young adults with a heart murmur accompanied by exercise intolerance. Complex pre-existing cardiopulmonary hemodynamics necessitate a holistic approach to the management of acute conditions like pulmonary edema in this cohort.