Multicentre study of fetal cardiac time intervals using magnetocardiography

Area of Science:

• Biomedical Engineering
• Fetal Cardiology
• Medical Physics

Background:

• Fetal magnetocardiography (MCG) is a non-invasive technique recording fetal heart electrical activity.
• Established reference values for fetal MCG waveform durations are crucial for accurate diagnosis.
• MCG offers high reliability from the 20th week of gestation onwards.

Purpose of the Study:

• To create a database of reference values for fetal magnetocardiogram (MCG) waveform durations.
• To aid in distinguishing between healthy and pathologic fetuses using MCG data.
• To assess the relationship between waveform durations and gestational age.

Main Methods:

• Collected fetal magnetocardiograms from 582 healthy patients in magnetically shielded rooms.
• Extracted durations of P-wave, PR interval, PQ interval, QRS complex, QT interval, T-wave, and QTc value.
• Statistically processed waveform durations and analyzed them as a function of gestational age.

Main Results:

• P-wave, PR interval, QRS complex, QT interval, and QTc durations showed a linear increase with gestational age.
• PQ interval and T-wave durations were found to be independent of fetal age.
• Provided regression lines and prediction intervals (90%, 95%, 98%) for waveform durations.

Conclusions:

• The established reference values align with existing literature.
• Wide data scatter is attributed to physiological variations, measurement systems, and processing subjectivity.
• The developed system can define normal ranges for fetal MCG waveforms, supporting diagnostic applications.