The Norwood operation is the first operation for hypoplastic left heart syndrome in the pathway to a single ventricle circulation. It consists of the connection of pulmonary artery (proximal end) to aorta, closure of the distal end of the pulmonary artery, enlargement of the hypoplastic aorta with a patch and an atrial septectomy. Pulmonary blood flow is provided via a Blalock-Taussig shunt or Sano shunt. This is a mixing lesion, both pulmonary vascular resistance and systemic vascular resistance should be kept at pre-operative levels.