Pulmonary atresia with intact ventricular septum is a duct-dependent complex cyanotic lesion. The complete obstruction at pulmonary valve level necessitates a R→L shunt at atrial level and a duct with a L→R shunt for pulmonary blood flow. High pressures in the right ventricle can cause coronary sinusoids, abnormal vascular connections between the right ventricle and the coronary system and a possible right ventricular pressure-dependent coronary circulation. Anaesthetic management is focussed on the ductal L→R shunt and the possible myocardial ischaemia due to the sinusoids.