Pulmonary vascular disease complicating the Blalock-Taussig anastomosis.

The pulmonary vascular bed was evaluated following a Blalock-Taussig shunt performed in 36 patients for decreased pulmonary blood flow. The time of follow-up ranged from one to 21 years after operation. No patients developed severe pulmonary changes in less than eight years after institution of the shunt. Ten of 20 patients having a shunt eight years or longer developed some degree of pulmonary vascular disease, mainly in the form of intimal fibrosis. This was severe in six of the 20 patients. As the duration of the shunt increased, so did the incidence of pulmonary vascular disease.