Pulmonary arterial anatomy in tetralogy of Fallot.

We have searched for any abnormalities of the pulmonary arteries visualized by angiography in 200 consecutive patients with tetralogy of Fallot. All the patients were studied by conventional right ventricular angiography in the right and left anterior oblique views. Thirty six patients (18%) showed a total of 61 pulmonary artery stenoses, 32 being severe (52%), 17 moderate (28%) and 12 mild (20%). Bifurcational stenoses were the most common (31), followed by stenosis of the main pulmonary trunk, the right or the left pulmonary arteries (22), combined central and peripheral stenosis (6), and isolated peripheral pulmonary artery stenosis (2). Nine patients showed segmental stenosis involving both the right and left pulmonary arteries and three of them had atresia of the left pulmonary artery. The detailed preoperative evaluation of obstruction within the pulmonary arterial pathways is essential in tetralogy of Fallot to ensure normalisation of the right ventricular pressure following total correction.