AbstractAn 8 year old girl presents with cyanosis, exertional dyspnoea, and palpitation only. X-ray displayed a typical coeur en sabot heart and auscultsation revealed a harsh ejection systolic murmur. Echocardiography confirmed Tetralogy of Fallot (McGoon ratio 1.3) and computed tomography was requested for further investigation of pulmonary stenosis. A vascular ring was detected, presenting asymptomatically and previously missed through echocardiography. The patient underwent a double-stage repair with ligation of an aortic arch. Recovery was unremarkable. This case highlights the limitations of echocardiography in detection of extra-cardiac anomalies.