Ductus venosus blood flow alterations in fetuses with obstructive lesions of the right heart.

OBJECTIVE

To assess the impact of isolated lesions of the fetal right heart on ductus venosus (DV) blood flow profiles.

METHODS

Retrospective evaluation of DV blood flow profiles in 83 fetuses with isolated right-sided cardiac lesions. Cases were divided into two groups. Group A had right-sided cardiac lesions associated with a large ventricular septal defect that equalized interventricular pressures (double outlet right ventricle (n = 12), tetralogy of Fallot (n = 19), pulmonary atresia (n = 5)). Group B had right-sided cardiac lesions with obstruction of the inflow (tricuspid atresia with ventricular septal defect (n = 14)) or obstruction of the outflow with intact ventricular septum (Ebstein's anomaly (n = 13), pulmonary stenosis (n = 13) and pulmonary atresia (n = 7)). Comparisons were made with 585 uneventful singleton pregnancies and previously published normative values.

RESULTS

Fetuses in Group B had significantly higher rates of abnormal DV flow profiles compared to Group A and controls (P < 0.01). Conversely, there were no significant differences concerning DV parameters between fetuses in Group A and controls. Despite these different DV flow characteristics, there were no significant differences concerning signs of cardiac failure and/or survival to the perinatal period between the two groups.

CONCLUSIONS

Right-sided cardiac lesions with obstruction of the inflow or outflow with intact ventricular septum are significantly associated with abnormally high pulsatilities in the DV and may even cause a reversal of flow during atrial contraction. These changes do not necessarily indicate cardiac failure, as they are primarily attributable to the special hemodynamics of the cardiac defect.