Factors determining peripheral pulmonary artery stenosis remodeling in children after percutaneous transluminal balloon angioplasty.

The peripheral pulmonary artery stenosis (PPS) that complicates congenital heart anomalies can improve after percutaneous transluminal balloon angioplasty (PTA), despite an initial poor response, but there is little information concerning the factors that determine such remodeling. The present study reviewed the hemodynamic and angiographic data before, immediately after, and at late follow-up after PTA for 17 lesions in 14 patients. Lesions were classified into either the (+) group (with pulmonary artery remodeling) or the (-) group (without remodeling). Remodeling was defined as an increase of more than 30% in the predictive percent of normal (%N) of the peripheral pulmonary artery diameter at late follow-up compared with the diameter immediately after PTA. Remodeling occurred in 6 of 17 lesions (35%), and the pressure gradient immediately after PTA was significantly smaller (<10 mmHg) in the (+) group than in the (-) group. Late expansion of the lesion (remodeling) occurs after PTA in some children with PPS and an adequate initial reduction in the pressure gradient favors subsequent remodeling.