title: Noninvasive fetal electrocardiography: an overview of the signal electrophysiological meaning, recording procedures, and processing techniques.
abstract: BACKGROUND
  Noninvasive fetal electrocardiography (fECG), obtained positioning electrodes on the maternal abdomen, is important in safeguarding the life and the health of the unborn child. This study aims to provide a review of the state of the art of fECG, and includes a description of the parameters useful for fetus clinical evaluation; of the fECG recording procedures; and of the techniques to extract the fECG signal from the abdominal recordings.
  
  
  METHODS
  The fetus clinical status is inferred by analyzing growth parameters, supraventricular arrhythmias, ST-segment variability, and fetal-movement parameters from the fECG signal. This can be extracted from an abdominal recording obtained using one of the following two electrode-types configurations: pure-abdominal and mixed. Differently from the former, the latter also provides pure maternal ECG tracings. From a mathematical point of view, the abdominal recording is a summation of three signal components: the fECG signal (i.e., the signal of interest to be extracted), the abdominal maternal ECG (amECG), and the noise. Automatic extraction of fECG includes noise removal by abdominal signal prefiltration (0.5-45 Hz bandpass filter) and amECG cancellation.
  
  
  CONCLUSIONS
  Differences among methods rely on different techniques used to extract fECG. If pure abdominal electrode configurations are used, fECG is extracted directly from the abdominal recording using independent component analysis or template subtraction. Eventually, if mixed electrode configurations are used, the fECG can be extracted using the adaptive filtering fed with the maternal ECG recorded by the electrodes located in the woman thorax or shoulder.
authors: Department of Information Engineering, Polytechnic University of Marche, Ancona, Italy.
authors: Angela
authors: A
authors: Agostinelli
authors: Department of Information Engineering, Polytechnic University of Marche, Ancona, Italy.
authors: Marla
authors: M
authors: Grillo
authors: Department of Clinical Sciences, Polytechnic University of Marche, Ancona, Italy.
authors: Alessandra
authors: A
authors: Biagini
authors: Department of Information Engineering, Polytechnic University of Marche, Ancona, Italy.
authors: Corrado
authors: C
authors: Giuliani
authors: United Hospitals "G. Salesi," Obstetrics and Gynecology Division, Ancona, Italy.
authors: Luca
authors: L
authors: Burattini
authors: Department of Information Engineering, Polytechnic University of Marche, Ancona, Italy.
authors: Sandro
authors: S
authors: Fioretti
authors: Department of Information Engineering, Polytechnic University of Marche, Ancona, Italy.
authors: Francesco
authors: F
authors: Di Nardo
authors: Department of Clinical Sciences, Polytechnic University of Marche, Ancona, Italy.
authors: Stefano R
authors: SR
authors: Giannubilo
authors: Department of Clinical Sciences, Polytechnic University of Marche, Ancona, Italy.
authors: Andrea
authors: A
authors: Ciavattini
authors: Department of Information Engineering, Polytechnic University of Marche, Ancona, Italy.
authors: Laura
authors: L
authors: Burattini
mesh_terms: D004562:Electrocardiography / Q000379:methods*; D004566:Electrodes; D005260:Female; D047109:Fetal Development / Q000502:physiology; D006340:Heart Rate, Fetal / Q000502:physiology*; D006801:Humans; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D012815:Signal Processing, Computer-Assisted; D013617:Tachycardia, Supraventricular / Q000175:diagnosis* / Q000503:physiopathology
keywords: abdominal ECG; fetal monitoring; noninvasive fetal ECG
references: Heart. 2007 Oct;93(10):1294-300
references: 17890709
references: IEEE Trans Biomed Eng. 1981 Apr;28(4):348-54
references: 7287034
references: Obstet Gynecol. 1977 Jul;50(1):49-55
references: 876522
references: Conf Proc IEEE Eng Med Biol Soc. 2005;2005:5639-42
references: 17281535
references: Conf Proc IEEE Eng Med Biol Soc. 2004;2004:5400-6
references: 17271567
references: Conf Proc IEEE Eng Med Biol Soc. 2006;2006:1394-7
references: 17945641
references: IEEE Trans Biomed Eng. 1985 Mar;32(3):230-6
references: 3997178
references: Biomed Tech (Berl). 2012 Oct;57(5):383-94
references: 25854665
references: IEEE Trans Inf Technol Biomed. 2007 Nov;11(6):628-38
references: 18046938
references: Ultrasound Obstet Gynecol. 2003 Jan;21(1):1-8
references: 12528152
references: Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 1996 May;53(5):R4326-R4329
references: 9964915
references: Pediatr Cardiol. 2004 May-Jun;25(3):234-51
references: 15360116
references: Physiol Meas. 2007 Apr;28(4):373-88
references: 17395993
references: Physiol Meas. 2007 Nov;28(11):1375-90
references: 17978422
references: Am J Obstet Gynecol. 2003 Jan;188(1):183-92
references: 12548215
references: Am J Obstet Gynecol. 2011 Jul;205(1):47.e1-5
references: 21514560
references: Biol Proced Online. 2009 Mar 27;11:263-95
references: 19495912
references: Cochrane Database Syst Rev. 2013 May 31;(5):CD000116
references: 23728630
references: Conf Proc IEEE Eng Med Biol Soc. 2006;2006:3106-9
references: 17945757
references: J Obstet Gynaecol Res. 2011 May;37(5):428-35
references: 21272152
references: Eur Heart J. 2011 Dec;32(24):3147-97
references: 21873418
references: Open Pacing Electrophysiol Ther J. 2010 Jan 1;3:4-20
references: 21614148
references: IEEE Trans Biomed Eng. 1997 Jan;44(1):51-9
references: 9214783
references: BMJ. 2001 Jun 16;322(7300):1436-7
references: 11408285
references: IEEE Trans Biomed Eng. 1998 Jan;45(1):133-7
references: 9444850
references: Biomed Tech (Berl). 2007 Feb;52(1):56-60
references: 17313335
references: Int J Pediatr. 2010;2010:401323
references: 20981293