Pulmonary artery pressure and resistance late after repair of tetralogy of Fallot with pulmonary atresia.

Twenty-one patients underwent elective hemodynamic and cineangiographic studies 1 to 9 years after repair of tetralogy of Fallot and pulmonary atresia. They were a subset of 41 patients who underwent complete repair between Jan. 1, 1973, and 1988. The mean and systolic pulmonary arterial pressure, as well as the pulmonary vasculature resistance, were abnormally high in 60% of the patients. Thirty-three percent of the patients were found to have pulmonary arterial segments that were not connected to the central and unbranched hilar portions of the right and left pulmonary arteries. The mean pulmonary artery pressure and the pulmonary vasculature resistance were correlated (inversely) with the number of centrally connected pulmonary arterial segments. The pulmonary vasculature resistance per pulmonary arterial segment was also inversely correlated with the number of centrally connected pulmonary arterial segments. Inferences: The finding that abnormalities in the pulmonary vasculature of centrally connected pulmonary arterial segments become more severe as the number of centrally connected pulmonary arterial segments decreased has implications as to hemodynamic effectiveness of unifocalization operations. Since others have found these abnormalities in the pulmonary vasculature to be age related, the findings support beginning the appropriate surgical treatment of patients with tetralogy of Fallot and pulmonary atresia very early in life.