Fetal magnetocardiography: development of the fetal cardiac time intervals.
OBJECTIVE
To analyse the physiologic development of fetal cardiac time intervals throughout gestation using fetal magnetocardiography (FMCG).


METHODS
FMCG data of 163 uncomplicated pregnancies (19th and 42nd gestational week) were analysed. Mean value, standard deviation, minimum and maximum of the duration of the P-wave, the QRS-complex, the PR and the QT-interval were plotted against gestational age.


RESULTS
QRS-complex, P wave and QT-interval showed a significant lengthening between the 20th and 42nd gestational week. The mean of the QRS complex raised from 36+/-4.7 ms (week 21-24) up to 48+/-5.2 ms (> or =37th week), (p=0.0001). The mean of the P-wave was between 47+/-5.9 ms (week 21-24) and 53+/-9.5 ms (> or =37th week), (p=0.05) and the mean of the QT-interval was 198+/-18 ms (week 21-24) and increased up to 244+/-23.9 ms (> or =37th week), (p=0.009). The PR-interval did not show a correlation with gestational age.


CONCLUSIONS
FMCG provides sufficient information about all parts of the fetal cardiac conduction system from the 19th gestational week on. It offers the possibility to analyse the shape and the duration of the PQRST-complex.
Kähler
Christiane
C
Department of Obstetrics and Gynaecology, Friedrich-Schiller University, Jena, Germany. christiane.kaehler@med.uni-jena.de
Schleussner
Ekkehard
E
Grimm
Barbara
B
Schneider
Alina
A
Schneider
Uwe
U
Nowak
Hannes
H
Seewald
Hans J
HJ
D000328:Adult; D015148:Cardiotocography / Q000295:instrumentation / Q000379:methods*; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005318:Fetal Heart / Q000502:physiology*; D005865:Gestational Age; D006329:Heart Conduction System / Q000502:physiology; D006801:Humans; D008280:Magnetics; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*