Assessing Fetal Heart Morphology and Function in Fetuses With Right Ventricular Outflow Obstruction by Fetal Heart Quantitative Technique.

Objectives: To investigate the clinical utility of the fetal heart quantification (Fetal HQ) technique in the assessment of morphological and functional changes in fetuses with right ventricular outflow obstruction (RVOTO).

Methods: This study included 53 fetuses with RVOTO and 30 age-matched normal controls. The RVOTO fetuses were divided into 2 groups based on the occurrence of other cardiovascular malformations: the simple pulmonary stenosis (PS group) and the conotruncal defects (CTD group). Size, shape, and contractility parameters of the fetal heart in 4-chamber view (4CV), left ventricle, and right ventricle (LV and RV) detected by fetal HQ.

Results: Fetuses with RVOTO exhibited an increased 4CV-width, with normal 4CV-Length. The end-diastolic diameter (ED) of the LV segments 1-22 was significantly greater in RVOTO fetuses. The sphericity index (SI) of the LV 24-segment was significantly smaller in the CTD and PS groups. Global longitudinal strain (GLS) and fractional area change (FAC) of the LV and RV were reduced in RVOTO fetuses.

Conclusion: Our results suggested that the characteristic changes in the morphology and function of the RVOTO fetal heart could be detected early by the HQ technique, which has clinical utility in analyzing the morphology of the RVOTO fetal heart in a quantitative manner.