Estimación no invasiva de la frecuencia cardiaca fetal mediante técnicas de separación ciega de fuentes

Estimación no invasiva de la frecuencia cardiaca fetal mediante técnicas de separación ciega de fuentes

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(VWLPDFLyQQRLQYDVLYDGHODIUHFXHQFLDFDUGLDFDIHWDOPHGLDQWH WpFQLFDVGHVHSDUDFLyQFLHJDGHIXHQWHV 1RQLQYDVLYHIHWDOKHDUWUDWHHVWLPDWHE\XVHRIEOLQGVLJQDOVHSDUDWLRQWHFKQLTXHV /XLV26DUPLHQWR3K' & ,QJ7HOHFRPXQLFDFLRQHV  ,ULQD9pOH],QJ7HOHFRPXQLFDFLRQHV  1DWDOLD)OyUH]3K',QJ(OHFWUyQLFD   -XDQ&2WHUR0'  )UDQFLVFR0DQULTXH0'  -RVp0LOOHW3K',QJ,QGXVWULDO  Bucaramanga, Colombia; Valencia, España. El diagnóstico anticipado de la enfermedad cardiaca durante la etapa de gestación del feto es uno de los retos de la medicina actual. La evaluación del electrocardiograma fetal es, por tanto, crucial para diagnosticar diversas anomalías cardiacas. No obstante, extraer el electrocardiograma fetal para su posterior valoración es una tarea complicada debido a muchos factores que abarcan desde las técnicas de adquisición del mismo y afección de factores fisiológicos, hasta la posible comorbidad entre diversas patologías. Desde años atrás la investigación en el estudio del electrocardiograma fetal y se han empleado técnicas tanto invasivas como no invasivas. La técnica no invasiva más usada es el ultrasonido Doppler pero éste no aporta información respecto a los parámetros morfológicos y temporales del electrocardiograma fetal; este último puede obtenerse mediante la colocación de eléctrodos sobre el abdomen y el tórax de la madre. Esta técnica abre la posibilidad de caracterizar la señal del electrocardiograma fetal; el problema radica en que la señal se mezcla con otras señales biomédicas, como la del electrocardiograma materno, la respiración, la actividad estomacal y las contracciones del útero, y por interferencias externas provocadas por la red eléctrica o el ruido térmico. Al día de hoy la señal del electrocardiograma fetal está aún en etapa de caracterización, motivo por el cual se hace necesario investigar nuevas metodologías para su estudio. El objetivo de este trabajo es utilizar técnicas de procesamiento de señales para extraer de manera no invasiva el electrocardiograma fetal partiendo del electrocardiograma superficial de la madre a fin de obtener una estimación de la frecuencia cardiaca fetal. PALABRAS CLAVE: frecuencia cardiaca fetal, electrocardiograma fetal, técnica de separación ciega, análisis de componentes independientes (ICA).

Early fetal diagnosis of heart disease during pregnancy is one of the current medical challenges. Therefore, the evaluation of the fetal electrocardiogram is crucial in the diagnosis of various cardiac abnormalities. However, the performance of the fetal electrocardiogram for its further assessment is a complicated task due to many factors ranging from EEG acquisition techniques and conditions of physiological factors, to the possible comorbidity between different pathologies.

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From years ago, the scientific investigation is focused in the study of the fetal electrocardiogram and both invasive and non-invasive techniques have been used. The non-invasive most used technique is the doppler ultrasound, but this does not provide information about the morphological and temporal parameters of the fetal electrocardiogram; the latter can be obtained by placing electrodes on the abdomen and thorax of the mother. This technique opens the possibility to characterize the fetal electrocardiographic signal but there is the problem that this signal may be mixed with other bio-medical signals such as maternal ECG,respiration, stomach activity, contraction of the uterus, and by external interference with AC power or thermal noise. As of today, the fetal electrocardiographic signal is still in a characterization stage, which is why it is necessary to investigate new methodologies for its study. The aim of this work is to use signal processing techniques to perform a non-invasive fetal electrocardiogram starting from the superficial electrocardiogram of the mother in order to obtain an estimate of the fetal heart rate. KEY WORDS: fetal heart rate, FECG (fetal electrocardiogram), BSS (blind source separation, ICA (independent component analysis). 5HY&RORPE&DUGLRO

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