Right and left ventricular dysfunction in fetuses with obstructive and nonobstructive Congenital Heart Disease (CHD)

Purpose: The purpose of this study was to measure biventricular function in human fetuses with CHD. Methods: This was a retrospective case/control study of 228 fetal echocardiograms from 151 patients, 89 with CHD and 62 matched healthy fetuses. Patients were classified as left (LVO) or right ventricular outflow obstruction (RVO), atrial or ventricular shunts (AVS), other (O), or normal hearts (NI). Left and right ventricular end systolic (ESV) and diastolic volumes (EDV), stroke volume (SV), and ejection fraction (EF) were measured using modified Simpson's rule. Ventricular volumes were indexed to 50th percentile normal values (%NV) using normative data from our laboratory. Results: Of our patients, 29 had LVO, 31 had RVO, 64 had AVS lesions, and 95 had normal hearts. LV and RV EDV were not different in NI and CHD fetuses (p>0.3). In the CHD group as a whole, LVESV and RVESV were significantly elevated to 217 and 207 %NV, respectively (p<0.0001). Patients with no obstructive CHD lesions (AVS) had significantly higher LV and RV ESV (195 and 205% NV, p<0.002) than NI controls. This corresponded to 19% and 15% decreases in LVSV and RVSV (p<0.05) and significantly lower ejection fraction. In LVO patients, LVESV and LVSV were more severely affected than in RVO or AVS groups (p<0.05). In RVO patients, both LV and RV ESV were significantly increased over AVS patients p<0.001). LV and RV EF were similar in NI fetuses (73% and 70%, respectively). Patients with LVO had significantly lower LVEF (44%) than patients with RVO (52%), other lesions (55%), or AVS lesions (55%). LVEF in the RVO, O, and AVS groups were similar, and significantly lower than NI fetuses. RVO patients had significant impairments in LV and RV EF, compared to patients with shunt lesions (p<0.01). Conclusions: All groups of the CHD fetuses had diminished LV and RV EF and SV compared to fetuses with normal hearts. Although SV and EF were diminished in all groups compared to controls, fetuses with left or right heart obstruction had significantly diminished SV and EF compared to those with no obstruction. We interpret these findings to mean that both diminished ventricular systolic function and increased afterload are important in the observed significant hemodynamic abnormalities.