Clinicopathologic Study of Placentas From Women With a Fontan Circulation

Abstract

Background: Pregnant women with a Fontan circulation have a high risk of obstetric complications, such as preterm delivery and small for gestational age (SGA), which may be affected by low blood flow to the placenta and hypoxia. This study investigated placental pathology in a Fontan circulation. Methods and Results:Eighteen pregnancies in 11 women with a Fontan circulation were reviewed. Pregnancy outcomes showed 9 miscarriages and 9 live births, with 4 preterm deliveries. Five neonates were SGA (<5th percentile). Eight placentas from live births in 7 women were available for the study. Five placentas had low weight placenta for gestational age, and 7 grossly showed a chronic subchorionic hematoma. Histological examination revealed all placentas had some form of histological hypoxic lesions: maternal vascular malperfusion in 7, fetal vascular malperfusion in 1, and other hypoxia-related lesions in 8. Quantitative analyses, including immunohistochemistry (CD31, CD68, and hypoxia inducible factor-1α antibodies) and Masson's trichrome staining, were also performed and compared with 5 control placentas. Capillary density and the area of fibrosis were significantly greater in placentas from women with a Fontan circulation than in control placentas. Conclusions:Placentas in a Fontan circulation were characterized by a high frequency of low placental weight, chronic subchorionic hematoma, and constant histological hypoxic changes, which could reflect altered maternal cardiac conditions and lead to poor pregnancy outcomes.

Fontan Circulation Associated Organ Abnormalities Beyond the Heart, Lungs, Liver, and Gut: A Systematic Review

“…Philips et al found prominent sub-chorionic fibrin deposition in all placentas ( 110 ). In the study by Yokouch-Konishi et al ( 109 ) seven of eight placentas had a chronic subchorionic hematoma. Other histopathologic changes included lesions associated with maternal vascular malperfusion, villous stromal fibrosis, and placental hypervascularity.…”

“…Our search returned 4 articles in total, of which 3 articles regarding abnormalities in the female sex organs ( 109 – 111 ) and one regarding sexual function in males ( 112 ).…”

“…Two studies assessed the placenta in pregnant patients with a Fontan circulation ( 109 , 110 ). In total 31 pregnancies were described, of which 12 pregnancies resulted in live births ( 109 , 110 ). Only 7 pregnancies were delivered at term ( 109 , 110 ).…”

“…In total 31 pregnancies were described, of which 12 pregnancies resulted in live births ( 109 , 110 ). Only 7 pregnancies were delivered at term ( 109 , 110 ). Both studies found placental weight varied significantly across pregnancy.…”

“…Both studies found placental weight varied significantly across pregnancy. An important proportion of placentas had low weight for gestational age ( 109 , 110 ). Histological examination revealed all placentas had some form of histological hypoxic lesions.…”