Two-dimensional strain to assess regional left and right ventricular longitudinal function in 100 normal foetuses

Area of Science:

• Cardiology
• Fetal Medicine
• Medical Imaging

Background:

• Myocardial velocity measurements lack sensitivity in fetal heart assessments.
• Doppler-derived strain imaging in fetuses has been limited by angle dependency and poor reproducibility.
• Two-dimensional (2D) tissue tracking strain (2D-S) echocardiography offers angle independence and improved reproducibility.

Purpose of the Study:

• To evaluate the feasibility and reproducibility of 2D-S for assessing regional myocardial deformation in the human fetal heart.
• To establish normal ranges for fetal ventricular strain using 2D-S.
• To assess the correlation between fetal age and myocardial strain.

Main Methods:

• 100 normal fetuses (20-32 weeks gestation) underwent 2D-S imaging.
• Left ventricle (LV) and right ventricle (RV) peak myocardial negative strain values were measured.
• Inter- and intra-observer variability was assessed.

Main Results:

• 2D-S data were successfully acquired from all fetuses, with post-processing taking approximately 3 minutes per dataset.
• Peak longitudinal strain values were consistent across ventricular walls (septum, lateral, RV free wall).
• Significant correlation found between gestational age and peak longitudinal strain (P < 0.001).
• Excellent inter-observer (<3%) and intra-observer (<6%) variability for strain measurements.

Conclusions:

• 2D-S is a feasible and reproducible technique for evaluating fetal cardiac function.
• The method is ready for clinical application in assessing regional ventricular function in fetuses.
• 2D-S provides a sensitive tool for non-invasive assessment of myocardial deformation in fetal cardiology.