Unicuspid Aortic Valve Disease: The Role of Imaging in Diagnosis and Timely Surgical Planning.

Unicuspid aortic valve (UAV) is a rare congenital anomaly that is often misdiagnosed as bicuspid aortic valve (BAV). UAV is associated with faster clinical progression, earlier need for surgical intervention, and a higher risk of complications. Accurate diagnosis is therefore crucial for timely management. We report the case of a 31-year-old male with a family history of BAV, who had been followed for more than 15 years with a presumed diagnosis of BAV. Serial transthoracic echocardiograms (TTEs) and cardiac MRI consistently suggested a bicuspid morphology. A previous transesophageal echocardiogram (TOE) was poorly tolerated. Despite progressive aortic regurgitation and root dilation, the diagnosis remained unchanged until the patient developed exertional dyspnea and presyncope. A repeat TOE revealed a unicuspid valve with severe eccentric regurgitation, which was later confirmed intraoperatively during aortic valve replacement with concomitant ascending aortic surgery. This case highlights the diagnostic challenges of UAV, the limitations of TTE and MRI in assessing valve morphology, and the pivotal role of TOE. Early clinical suspicion and timely multimodal imaging are essential to avoid delayed recognition and to optimize surgical planning and outcomes.