Quadricuspid pulmonary valve: A rare cause of pulmonary artery aneurysm.

A 17-year-old male presented to our hospital from an external center with complaints of chest pain and shortness of breath, referred with preliminary diagnoses of pulmonary stenosis and pulmonary artery dilation. Echocardiography revealed moderate pulmonary regurgitation and mild pulmonary stenosis. Coronary computed tomography (CT) angiography showed normal coronary arteries and no presence of a patent ductus arteriosus, but an aneurysmal dilation of up to 4 cm was observed in the pulmonary artery. The patient was found to have a quadricuspid (QPV) pulmonary valve, while the aortic valve appeared normal. No phenotypic anomalies or accompanying aortic or lung abnormalities were detected in this case. Our case represents the first in the pediatric age group diagnosed via CT scan. Our study contributes insights into the relationship between QPV anomaly and pulmonary artery aneurysm, aiding in the diagnosis and management of these rare conditions. Furthermore, our findings highlight the importance of evaluating the possibility of QPV in patients with pulmonary valve stenosis, regurgitation, or artery aneurysm, emphasizing the significance of coronary CT angiography in the diagnostic process.