Pulmonary artery stiffness in fetuses with tetralogy of Fallot.

PURPOSE: This study evaluated the elastic characteristics of the pulmonary trunk and distal branches in fetuses diagnosed with tetralogy of Fallot (TOF) using Doppler echocardiography.

METHODS: Data on 42 fetuses diagnosed with TOF and 84 gestational age-matched normal fetuses were prospectively collected from the Second Xiangya Hospital of Central South University between August 2022 and January 2023. The severity of TOF was classified into three categories based on the z-score of the pulmonary annulus diameter: mild (z-score ≥-2), moderate (-4<z-score<-2), and severe (z-score ≤-4). Pulmonary artery stiffness (PAS) in the main pulmonary artery (MPA), distal left pulmonary artery (DLPA), and distal right pulmonary artery (DRPA) was measured using pulsed-wave Doppler imaging. Differences in clinical data and echocardiographic parameters were compared between the TOF group and the normal group, as well as among TOF subgroups.

RESULTS: Compared with the normal group, the MPA-PAS in fetuses with TOF was significantly higher, while the DLPA-PAS and DRPA-PAS were notably lower (all P<0.05). The MPA-PAS of fetuses with severe TOF was higher than that of those with mild and moderate TOF (all P<0.05). However, there were no significant differences in the DLPA-PAS or DRPA-PAS among fetuses with mild, moderate, and severe TOF (all P>0.05).

CONCLUSION: Fetuses diagnosed with TOF exhibited increased vascular stiffness in the MPA and reduced stiffness in the distal pulmonary artery (PA). Larger-scale follow-up studies are required to elucidate the relationships between these changes in vascular stiffness and PA development in patients with TOF.