Pressure recovery in pediatric patients with congenital aortic stenosis: Correlation with doppler/catheter pressure discrepancies

Pressure recovery is an important source of discrepancy between Doppler-estimated and catheter-measured gradients in aortic stenosis. The clinical relevance of this fluid dynamic principle has not been established in pediatric patients with congenital aortic stenosis. We retrospectively measured pressure recovery in 21 patients (11 with bicuspid aortic valves). Pressure recovery was correlated with actual Doppler/catheter discrepancies (r=0.48). The correlation was significantly weaker for bicuspid valves (r=0.21) than for trileaflet valves (r=0.69). Doppler-estimated gradients were adjusted by pressure recovery calculations in 15 of 21 children for whom Doppler overestimated the catheter-measured gradients. The correlation did not change significantly with adjustment (r=0.79 vs. r=0.81). However, the mean percent difference decreased from 34%±6% to 22%±5%. Pressure recovery accounts for a significant portion of Doppler/catheter discrepancies in pediatric patients with congenital aortic stenosis.