Abstract 3277: Analysis of Fetal Intra-thoracic Anomalies and Their Impact on Myocardial Kinesis Using Doppler Tissue Imaging
Background: Giant intra-thoracic mass (ITM) in the fetus such as congenital cystic adenomatoid malformation can lead to cardiac dysfunction and hydrops, while in congenital diaphragmatic hernia (CDH) cardiac dysfunction and hydrops are rare. It is postulated that in ITM intra-thoracic pressure is increased while in CDH intra-thoracic pressure is normal. Analysis of myocardial kinesis using Doppler tissue imaging (DTI) may help explain the cardiac pathophysiology of these disorders.
Objective: To investigate the effects of ITM and CDH on patterns of fetal myocardial kinesis using DTI.
Methods: The spectrum of DTI velocities throughout gestation (14–38 wks) was determined in 167 normal fetuses. We compared fetuses with ITM (n=18, mean age 27 wks) and CDH (n=18, mean age 22 wks) to age-matched controls. Ea (early diastole), Aa (atrial contraction), Sa (peak systole) tissue velocities were measured at the lateral free walls of the RV and LV. Blood flow velocities of early diastole (E wave) and atrial contraction (A wave) across the mitral and tricuspid valves were also recorded. Indices were calculated, including the E/Ea ratio, a measure of ventricular filling pressure.
Results: In ITM, LV measures of myocardial kinesis were no different than normal, however all RV measures (Ea, Aa, Sa) demonstrated significantly lower velocities (see table⇓). For CDH, measures of LV filling (MV E and A waves) were lower than normal. E/Ea was normal for both the RV and LV in CDH, however RV E/Ea was significantly higher in ITM.
Conclusions: In CDH, LV filling is diminished however ventricular filling pressures are normal. In ITM, RV kinesis is impaired and RV filling pressures are increased. Elevation of right sided filling pressures explains the potential for development of hydrops in the fetus with ITM but not CDH. Serial monitoring of RV E/Ea may prove useful in managing the fetus with giant ITM as well as help elucidate complex physiological processes in other disorders affecting the fetal heart.