Changes in the aortic and pulmonary diameters in a fetus with hypoplastic left heart syndrome

Abstract

We diagnosed hypoplastic left heart syndrome in a 26-week-old fetus using fetal echocardiography. Color Doppler ultrasonography was helpful for evaluating the structural abnormalities. The diameters of the aorta and the pulmonary artery were measured periodically from 26 to 38 weeks of gestation. Aortic diameter was below the normal range throughout gestation. The diameter of the pulmonary artery was normal at 26 weeks of gestation but gradually dilated and was abnormally dilated after the 36th week of gestation. Here we discuss the cause of enlarged pulmonary artery in fetal hypoplastic left heart syndrome.

Unfavorable postnatal outcome with significant dilation of the fetal main pulmonary artery near term

“…Is neonatal pulmonary hypertension induced by long term chronic hypoxia not only in diaphragmatic hernia, but also like in high‐altitude or in selected CHDs (Herrera et al, 2010)? In case report of HLHS presented by Tada in the 26 week of gestation the diameter of pulmonary artery was normal and gradually dilated to significant dilatation after the 36th week of gestation (Tada et al, 2003). Maybe the cause of enlarged pulmonary artery in fetal hypoplastic left heart syndrome was abnormal pulmonary lungs development in third trimester leading to pulmonary hypertension seen after birth?…”

Prenatal dilatation of the pulmonary artery in the third trimester – important information for paediatric cardiologist or for neonatologist? Case report

“…The broad pulmonary trunk should draw special attention in the context of predicting the postnatal condition and the assessment of cardiopulmonary efficiency of newborns [1][2]. A dilated MPA in the three-vessel view could be found in isolated pulmonary valve stenosis with post-stenotic dilatation of the main pulmonary artery or in tetralogy of Fallot with absent pulmonary valve syndrome [3][4][5][6][7][8].…”

“…Accelerating flows through the ductus arteriosus, tricuspid valve dysplasia/dysfunction, higher spectrum of the fetal pulmonary vein downflow, extended atrial conduction time, could be presented in the course of transient occlusion of the ductus arteriosus and in utero infection [19][20][21][22][23][24][25][26][27][28][29][30]. So, after the exclusion of the structural congenital heart defects as a base of the dilatation of the main pulmonary artery, we should consider other pathophysiological mechanisms, and neonatologists should be aware of this abnormal finding (Table 2).…”

“…• Larger MPA diameter best correlates with postnatal death and respiratory morbidity in CDH • Fetal MPA diameters are probably related to the severity of pulmonary hypoplasia in CDH • PA diameters appeared to be correlated with prognosis in infants with CDH + LH [25,27,43,44] Pulmonary hypertension/HLHS • Enlarged MPA in fetal hypoplastic left heart syndrome • There were statistical differences between PA/AO ratio at 39 weeks of gestation in pulmonary hypertension and HLHS groups [28,43] Coarctation of the aorta-CoA • Fetuses whose PA/Ao is greater than 1.6 are more likely to suffer from CoA [13,16]…”

“…The broad pulmonary trunk in the third trimester of gestational age should be given special attention in the context of predicting the postnatal compromise and the assessment of cardiopulmonary efficiency of newborns [1][2][3][4][5][6][7][8][9]. An intrauterine environment, an in-utero infection, and fetal pulmonary hypertension can contribute to abnormal prenatal echocardiographic findings and may predict abnormal newborns' adaptation to ex-utero life [1][2][3][4][5][6][7][8][9].…”