Assessment of left ventricular pre-ejection period in the fetus using simultaneous magnetocardiography and echocardiography.
BACKGROUND
Fetal magnetocardiography (fMCG) is a promising new technique for assessing fetal rhythm; however, no prior studies have utilized fMCG to evaluate human fetal electromechanical physiology. Pre-ejection period (PEP) is an important measure of the electromechanical activation of the heart, and is altered by disease states and arrhythmias.


METHODS
A novel technique was used to assess fetal PEP and its relationship to other fetal systolic time intervals, RR interval, and gestational age (GA). 25 normal human fetuses between 19 and 38 weeks' gestation were studied using simultaneous pulsed Doppler ultrasound and fMCG. Correlations among PEP, ejection time, QRS width and RR interval were assessed using linear regression.


RESULTS
Across all subjects, PEP was found to correlate with GA (R = 0.57, p < 0.0001), QRS width (R = 0.35, p = 0.026), and RR interval (R = 0.37, p = 0.018). In individual sessions, PEP negatively correlated beat-to-beat with the preceding RR interval.


CONCLUSIONS
PEP exhibits developmental trends that provide a better understanding of the normal development of the human fetal heart.
Department of Medical Physics, University of Wisconsin, Madison, USA.
Nana Aba
NA
Mensah-Brown
Ronald T
RT
Wakai
Bageshree
B
Cheulkar
Shardha
S
Srinivasan
Janette F
JF
Strasburger
D015150:Echocardiography, Doppler; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging* / Q000502:physiology; D005865:Gestational Age; D006340:Heart Rate, Fetal; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000254:growth & development; D006801:Humans; D053798:Magnetocardiography; D011247:Pregnancy; D013318:Stroke Volume; D013599:Systole / Q000502:physiology; D016276:Ventricular Function