Is Doppler an accurate predictor of catheterization gradients for postoperative branch pulmonary stenosis?

Branch pulmonary stenosis may develop after repair of congenital heart disease. Echocardiography, used for the serial evaluation of these patients, yields Doppler gradients that are used in decisions regarding the need for intervention for branch pulmonary stenosis. The purpose of this study was to assess the value of Doppler echocardiography in quantifying the degree of branch pulmonary stenosis in patients who were postoperative. Patients after repair of transposition of the great arteries (n = 14), truncus arteriosus (n = 12), or tetralogy of Fallot (n = 14) who underwent echocardiography within 3 months of a postoperative catheterization were identified. Doppler peak instantaneous gradients were compared with catheter peak-to-peak gradients. Despite significant correlation between Doppler and catheterization peak gradients, Doppler gradients tended to overestimate the catheterization gradients, and the agreement between the 2 measurements was poor. These findings suggest that Doppler gradients should be interpreted cautiously in this setting.