The Silent Stranglehold: Multimodal Imaging in Postoperative Pulmonary Artery Stenosis.

A 15-year-old adolescent with complex congenital heart disease (CHD), previously diagnosed with anomalous origin of the right pulmonary artery from the ascending aorta and patent ductus arteriosus (PDA), presented with chest tightness. Transthoracic echocardiography (TTE) revealed moderate pulmonary artery stenosis (29 mmHg gradient), but computed tomography angiography (CTA) confirmed severe stenosis at the right pulmonary artery origin, and invasive angiography quantified a 32-mmHg systolic pressure gradient. Following successful pulmonary artery stenting, the gradient decreased to 5 mmHg, with complete symptom resolution. This case underscores the critical role of multimodal imaging in diagnosing postoperative pulmonary artery stenosis, guiding interventional timing, and preventing irreversible complications such as pulmonary hypertension and vascular remodeling in high-risk CHD populations.