Z Geburtshilfe Neonatol 2015; 219 - FV01_1
DOI: 10.1055/s-0035-1566449

Phase-rectified signal averaging method to predict intermediate perinatal outcomes in infants with very preterm fetal growth restriction – a secondary analysis of TRUFFLE-trial

SM Lobmaier 1, JU Ortiz 1, G Schmidt 2 K Schneider 1, TRUFFLE Study Group London, UK
  • 1Frauenklinik, Klinikum rechts der Isar, Technische Universität München, München, Germany
  • 2I. Med. Klinik, Klinikum rechts der Isar, Technische Universität München, München, Germany

Background: Phase-rectified signal averaging (PRSA) – an innovative signal processing technique- is currently the best method in adult cardiology to predict survival after myocardial infarction. Our own research group firstly applied this method in fetal medicine. The new parameter “average acceleration capacity” (AAC) for surveillance of the fetal autonomic nervous system was derived and validated in prospective studies at hospital “Klinikum rechts der Isar”. AAC differentiated significantly better between growth restricted (FGR) fetuses and controls than the currently used computerized CTG parameter “short term variation” (STV). These results could be confirmed meanwhile by several other centres. The aim of this study was to investigate the longitudinal course of PRSA related patterns in severely growth restricted fetuses and their prognostic accuracy regarding perinatal and neurological outcome.

Method: CTG raw data (from 279 fetuses available) of the “safety net” from eight centres participating in the multicentre randomized “TRUFFLE” trial were analysed secondary by PRSA method. AAC and average deceleration capacity (ADC) were calculated. The longitudinal course of AAC, ADC and STV was described and the correlation of the mentioned parameters and perinatal as well as neurological outcome were evaluated.

Results: AAC and ADC showed a significant decrease beginning three days (versus STV two days) before performed delivery due to impending fetal compromise, preeclampsia or protocol. Delta AAC showed a tendency to predict acidosis (pH < 7.10) and APGAR < 7 as well as antenatal death more accurate than delta STV.

Conclusion: In severe FGR situation a progressive compromise of fetal autonomic nervous system is evident. The decrease of AAC is associated with adverse perinatal outcome and intrauterine demise. The next step should be to perform a prospective multicentre study aiming to predict adverse pregnancy outcome by (changes in) AAC.