Infantile Manifestation of a Rare Congenital Cardiac Triad Comprising Left Ventricular Noncompaction, Large Patent Ductus Arteriosus, and Bicuspid Aortic Valve

Left ventricular noncompaction (LVNC) is a rare cardiomyopathy marked by excessive myocardial trabeculations and profound intertrabecular recesses, frequently identified incidentally, yet occasionally linked to significant cardiac dysfunction and adverse outcomes. It is uncommon for LVNC to coexist with other congenital cardiac anomalies, and the concurrent occurrence of LVNC, patent ductus arteriosus (PDA), and bicuspid aortic valve has not been previously reported. We report a 7-month-old female infant who exhibited exertional cyanosis and an episode of syncope in early infancy. Transthoracic echocardiography revealed that the left ventricle was not functioning correctly and that the aorta was too narrow. Therefore, a cardiac computed tomography angiography (CTA) was performed to gather further information. The CTA showed a significant PDA with flow in both directions, predominantly right-to-left shunting. This was caused by pulmonary arterial hypertension, which caused the pulmonary arteries (PAs) and descending thoracic aorta to have different levels of contrast opacification. There was significant dilation in all the heart’s chambers and PAs. In addition, classic imaging features of LVNC were identified, including prominent trabeculations and deep intertrabecular recesses, with a noncompacted to compacted myocardial ratio > 3. The aortic valve had two cusps and thickened leaflets and raphes, which caused severe valvular stenosis. These three congenital defects probably worked together to cause early heart failure, pulmonary hypertension, and a high risk of death. This case exemplifies an extraordinarily rare congenital cardiac triad that manifests in infancy, emphasizing the critical importance of CTA in thorough anatomical and functional evaluation. Early identification of intricate associations is essential for risk stratification, multidisciplinary management, and prognostication in affected infants.