Simulation of foetal phonocardiographic recordings for testing of FHR extraction algorithms

A valuable alternative to traditional diagnostic tools, such as ultrasonographic cardiotocography, to monitor general foetal well-being by means of foetal heart rate analysis is foetal phonocardiography, a passive and low cost recording of foetal heart sounds. In this paper, it is presented a simulator software of foetal phonocardiographic signals relative to different foetal states and recording conditions (for example different kinds and levels of noise). Before developing the software, a data collection pilot study was conducted with the purpose of specifically identifying the characteristics of the waveforms of the foetal and maternal heart sounds, since the available literature is not rigorous in this area. The developed software, due to the possibility to simulate different physiological and pathological foetal conditions and recording situations simply modifying some system parameters, can be useful as a teaching tool for demonstration to medical students and others and also for testing and assessment of foetal heart rate extraction algorithms from foetal phonocardiographic (fPCG) recordings. On this purpose, the simulator software was used to test an algorithm developed by the authors for foetal heart rate extraction considering different foetal heart rate parameters and signal to noise ratio values. Our tests demonstrated that simulated fPCG signals are very close to real fPCG recordings.

[1]  Jacob Cohen,et al.  Weighted kappa: Nominal scale agreement provision for scaled disagreement or partial credit. , 1968 .

[2]  Anupam Shukla,et al.  System simulation and comparative analysis of foetal heart sound de-noising techniques for advanced phonocardiography , 2007 .

[3]  D I Fotiadis,et al.  A Non-invasive Methodology for Fetal Monitoring during Pregnancy , 2009, Methods of Information in Medicine.

[4]  Mahmoud Moghavvemi,et al.  A non-invasive PC-based measurement of fetal phonocardiography , 2003 .

[5]  M. R. Ortiz,et al.  The use of wavelet packets to improve the detection of cardiac sounds from the fetal phonocardiogram , 1999, Computers in Cardiology 1999. Vol.26 (Cat. No.99CH37004).

[6]  Zoltán Benyó,et al.  An advanced method in fetal phonocardiography , 2003, Comput. Methods Programs Biomed..

[7]  Gábor Hosszú,et al.  Fetal phonocardiography - Past and future possibilities , 2011, Comput. Methods Programs Biomed..

[8]  Maria Romano,et al.  Time-frequency analysis of CTG signals , 2009 .

[9]  Maria Romano,et al.  An algorithm for FHR estimation from foetal phonocardiographic signals , 2010, Biomed. Signal Process. Control..

[10]  P. Bifulco,et al.  A simulating software of fetal phonocardiographic signals , 2010, Proceedings of the 10th IEEE International Conference on Information Technology and Applications in Biomedicine.

[11]  Maria Romano,et al.  PSD modifications of FHRV due to interpolation and CTG storage rate , 2011, Biomed. Signal Process. Control..

[12]  J Nagel,et al.  New diagnostic and technical aspects of fetal phonocardiography. , 1986, European journal of obstetrics, gynecology, and reproductive biology.

[13]  MA Hasan,et al.  Detection and Processing Techniques of FECG Signal for Fetal Monitoring , 2009, Biological Procedures Online.

[14]  J. Habetha,et al.  Detection of S1 and S2 Heart Sounds by High Frequency Signatures , 2006, 2006 International Conference of the IEEE Engineering in Medicine and Biology Society.

[15]  F. Kovacs,et al.  Long-term Phonocardiographic Fetal Home Monitoring for Telemedicine Systems , 2005, 2005 IEEE Engineering in Medicine and Biology 27th Annual Conference.

[16]  Richard Cookson,et al.  Royal College of Obstetricians and Gynaecologists. The Use of Electronic Fetal Monitoring full guidance published by the RCOG. RCOG Clinical Effectiveness Support Unit, London , 2001 .

[17]  S. Emery,et al.  Dynamic analysis of beat-to-beat fetal heart rate variability recorded by SQUID magnetometer: quantification of sympatho-vagal balance. , 2002, Early human development.

[18]  Lionel Tarassenko,et al.  Quantifying errors in spectral estimates of HRV due to beat replacement and resampling , 2005, IEEE Transactions on Biomedical Engineering.

[19]  Jacob Cohen.  A Coefficient of Agreement for Nominal Scales , 1960 .

[20]  Maria Romano,et al.  An algorithm for the recovery of fetal heart rate series from CTG data , 2007, Comput. Biol. Medicine.

[21]  A Baskaran,et al.  Fetal heart sound analysis: a preliminary evaluation. , 1996, The Medical journal of Malaysia.

[22]  L. Devoe,et al.  Electronic fetal monitoring: does it really lead to better outcomes? , 2011, American journal of obstetrics and gynecology.

[23]  A. K. Mittra,et al.  Development of an artificial womb for acoustical simulation of mother's abdomen , 2008 .

[24]  D. G. Talbert,et al.  Wide Bandwidlt Fetal Phonography Using a Sensor Matched to the Compliance of the Mother's Abdominal Wall , 1986, IEEE Transactions on Biomedical Engineering.

[25]  O Axelsson,et al.  Ultrasound and adverse effects , 2002, Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology.

[26]  L. Groome,et al.  Spectral analysis of heart rate variability during quiet sleep in normal human fetuses between 36 and 40 weeks of gestation. , 1994, Early human development.

[27]  A. Luisada,et al.  THE DURATION OF NORMAL HEART SOUNDS , 1949, British heart journal.

[28]  Mahmoud Moghavvemi,et al.  Real time analysis of fetal phonocardiography , 2000, 2000 TENCON Proceedings. Intelligent Systems and Technologies for the New Millennium (Cat. No.00CH37119).

[29]  Patrick E. McSharry,et al.  A dynamical model for generating synthetic electrocardiogram signals , 2003, IEEE Transactions on Biomedical Engineering.

[30]  Anil Kumar Tiwari,et al.  Development of a Signal Simulation Module for Testing of Phonocardiography Based Prenatal Monitoring Systems , 2009, 2009 Annual IEEE India Conference.

[31]  G. Moody,et al.  Power spectral density of unevenly sampled data by least-square analysis: performance and application to heart rate signals , 1998, IEEE Transactions on Biomedical Engineering.

[32]  Ferenc Kovács,et al.  A rule-based phonocardiographic method for long-term fetal heart rate monitoring , 2000, IEEE Transactions on Biomedical Engineering.

[33]  J. M. Swartjes,et al.  Computer analysis of antepartum fetal heart rate: 2. Detection of accelerations and decelerations. , 1990, International journal of bio-medical computing.

[34]  L. Oppenheimer,et al.  7 Power spectral analysis of fetal heart rate , 1994 .