Morphological Changes in Aorta and Pulmonary Artery after Norwood Operation for Hypoplastic Left Heart Syndrome. Significance of Angiocardiography

Overview

The long-term result of the Norwood operation for hypoplastic left heart syndrome depends on the development of the aorta and pulmonary arteries. Nine patients were examined angiocardiographically 5 - 11 months after surgery. In one patient an aneurysm of the ascendent aorta was found. In two infants recoarctation was identified, which was treated by balloon angioplasty in one of them. In three patients collateral circulation as a result of stenosis of the brachiocephalic trunk at the site of the shunt was present. One patient has an aneurysm of the brachiocephalic trunk proximal to the anastomosis. The pulmonary vascular bed was well developed in the majority of patients. The diameter of the right pulmonary artery was 4 - 8.5 mm (med. 6.6 mm), the diameter of the left pulmonary artery was 5.2 - 8.2 (med. 5.7 mm). McGoon index was 1.3 - 2.0 (med. 1.7), Nakata index 102 - 296 mm2/m2 (med. 190 mm2/m2). In 3 patients local stenosis of the right pulmonary artery at the site of anastomosis was found. One of them had a long stenosis behind the aortic aneurysm. In 3 patients the left branch was narrower. After the Norwood operation alterations of the aorta, brachiocephalic trunk and pulmonary arteries are common and an angiocardiographic examination is necessary for their visualisation. Arterial collateral circulation is a sign of recoarctation or stenosis of a brachiocephalic trunk. Recoarctation can be treated by angioplasty. At the site of anastomosis narrowing of the pulmonary artery is common. The left pulmonary artery branch is sometimes narrower than he right one. The pulmonary vascular bed has usually an adequate capacity.

Key words:
circulation, heart, congenital heart disease, hypoplastic left heart syndrome, cardiac surgery, Norwood operation, angiocardiography, infant