Treatment approach to unilateral branch pulmonary artery stenosis.

Unilateral proximal pulmonary artery stenosis is often seen in the setting of postoperative congenital heart disease. Accurate assessment of the hemodynamic significance of such a lesion is important so as to determine "When to intervene?" A thorough evaluation should include symptom assessment, anatomical assessment through detailed imaging, functional assessment using differential pulmonary blood flow measurement and cardiopulmonary exercise testing. Symptoms of exertional dyspnea or intolerance, decreased pulmonary blood flow to stenosed lung, and abnormal exertional performance would be factors to pursue therapy in the setting of significant anatomical narrowing. Safe and effective therapy can be offered through transcatheter or surgical techniques and has been shown to improve exertional performance.