Fetal Myocardial Thickening Measured by Ultrasonic-Based Technique Called ‘Phased-Tracking Method’

Abstract

Objective: To evaluate fetal myocardial movement by using newly developed ultrasonic technique. Methods: We analyzed 50 normal fetuses between 25 and 41 weeks’ gestation for changes in thickness of fetal myocardium using the phased-tracking method, a technique with high vertical distance resolution and the potential to evaluate fine ventricular wall movements. We analyzed differences in the rate of change in ventricular wall thickness and in changes in the inner and outer wall layers with advancing gestation. We also analyzed myocardial thickening period and evaluated the ratio of increasing thickness period to stroke interval. Results: Mean thickness changing rate was significantly higher in the right (1.18 ± 0.34 m/s/m) than in the left ventricular wall (0.86 ±0.31 m/s/m) (p < 0.001). Mean ratio of increasing thickness period to stroke interval was significantly higher in the right (0.57 ± 0.064) than in the left ventricle (0.46 ± 0.075) (p < 0.001), indicating that myocardial contraction in the fetal right ventricle predominates. The thickness-changing rate of the bilateral ventricular walls was positively and linearly correlated with gestational age. The myocardial-wall thickness-changing rate was higher in the outer layer than in the inner layer in late gestation. Conclusions: We conclude that measurement of the thickness-changing rate of fetal ventricular walls using the phased-tracking method might be useful for evaluation of fetal cardiac function.

Congenital Cardiac Anomalies

“…Interestingly, 2 cases were called abnormal when postnatal evaluation or autopsy confirmed normal hearts. In 1 case in which right ventricular hypertrophy was overcalled, perhaps nomograms of ventricular size should have been consulted 26 . In the second case, 2 experienced fetal cardiologists (>17 years of experience) thought that multiple intraventricular echogenic masses represented myxomas and possibly tuberous sclerosis, which resulted in pregnancy termination.…”

Multilayer radial systolic strain can identify subendocardial ischemia: An experimental tissue Doppler imaging study of the porcine left ventricular wall

“…35 Also by using a phase-tracking method, it is possible to measure thickening in two layers in the fetal heart. 36 The 4 layer measurements in this epicardial experimental study is beyond clinical use. In transthoracic applications a frequency 5 MHz is too high for most measurement in adults.…”

Noninvasive early detection of anthracycline‐induced cardiotoxicity in patients with hematologic malignancies using the phased tracking method

“…The PTM, which was employed in this study, has been applied to clinical studies by many researchers, that is, noninvasive evaluation of the myocardial property of contraction and relaxation [5,30,31], elasticity of the arterial wall [32][33][34][35][36], and fatal cardiac or artery [7,8,37]. Although in this study, we reported only V ave during systolic time at the left ventricular septum, we hypothesize that the development of more detailed myocardial damaging process becomes clear by analyzing the continuous temporal relationship with V ave , V max , and color image.…”