Magnetocardiography in the evaluation of fetuses at risk for sudden cardiac death before birth.
BACKGROUND
We hypothesized that fetuses at risk for sudden death may have abnormal conduction or depolarization, ischemia, or abnormal heart rate variability (HRV) detectable by magnetocardiography.


METHODS
Using a 37-channel biomagnetometer, we evaluated 3 groups of fetuses at risk for sudden death: group 1, critical aortic stenosis (AS); group 2, arrhythmias; and group 3, heart failure and in utero demise. Five to 10 recordings of 10-minute duration were recorded, and signal was averaged to determine rhythm, conduction intervals, HRV, and T-wave morphology.


RESULTS
In group 1, 2 of 3 had atrial and ventricular strain patterns. In (n = 53) group 2, 15% had prolonged QTc and 17% had T-wave alternans (TWA). Of 23 group 2 fetuses with atrioventricular block, 74% had ventricular ectopy, 21% had junctional ectopic tachycardia, and 29% had ventricular tachycardia. Group 3 (n = 2) had abnormal HRV and TWA.


CONCLUSIONS
Repolarization abnormalities, unexpected arrhythmias, and abnormal HRV suggest an arrhythmogenic mechanism for "sudden cardiac death before birth."
Cuneo
Bettina F
BF
The Heart Institute for Children, Hope Children's Hospital, Rush Medical College, Chicago, IL, USA. cuneo@thic.com
Strasburger
Janette F
JF
Wakai
Ronald T
RT
D016757:Death, Sudden, Cardiac / Q000453:epidemiology* / Q000517:prevention & control; D005260:Female; D005313:Fetal Death / Q000175:diagnosis* / Q000453:epidemiology*; D005323:Fetal Monitoring / Q000379:methods / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D053798:Magnetocardiography / Q000706:statistics & numerical data*; D008297:Male; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016019:Survival Analysis; D015996:Survival Rate; D014481:United States / Q000453:epidemiology