FETUSES with congenital heart disease (CHD), especially single ventricle (SV) CHD, exhibit reduced mid-gestational placental blood flow, increased placental maternal vascular malperfusion (MVM) defects, and impaired growth.
This prospective case-control study investigated the relationship between placental blood flow, placental pathology, and fetal outcomes in CHD. The study included 38 CHD fetuses (28 with SV CHD) and 36 controls. Umbilical venous volume flow (UVVF) was measured using second-trimester fetal echocardiograms, and placental samples underwent detailed pathological analysis. Standard statistical methods, including regression analyses, were used to evaluate relationships between UVVF, placental defects, and growth outcomes.
CHD fetuses had a 15% reduction in mid-gestational UVVF indexed to fetal weight (P < 0.01) and a 27% reduction in UVVF as a proportion of fetal cardiac output (P < 0.01) compared to controls. Placental MVM lesions were significantly more common in CHD fetuses than controls (44% vs 18%, P < 0.05), particularly high-grade lesions (39% vs 9.1%, P = 0.05). While fetal vascular malperfusion (FVM) lesions trended higher in CHD fetuses (42% vs 23%, P = 0.10), only placental MVM lesions were significantly associated with lower birth weight in CHD fetuses (P < 0.001). No relationship was found between UVVF and placental pathology or fetal growth.
This study highlights that decreased mid-gestational placental blood flow, increased placental malperfusion defects, and impaired growth are distinct features of CHD fetuses. The findings suggest that MVM lesions may drive growth impairments in CHD, independent of fetal vascular malperfusion or UVVF. For clinical practice, these results underscore the need to monitor placental health and fetal growth in pregnancies affected by CHD. Future research should aim to clarify the mechanisms underlying abnormal placental development in CHD and explore therapeutic approaches to optimise placental function and fetal outcomes.
Katrina Thornber, EMJ
Reference
Josowitz R et al. Congenital heart disease fetuses have decreased mid-gestational placental flow, placental malperfusion defects, and impaired growth. JACC: Advances. 2025;4(2):101559.
