Use of Electronic Cardiac Auscultation in the Newborns (Practical Aspects)

Intriduction. Proper investigation of the abnormalities in heart sounds is known to provide vital clinical information that can assist in the diagnosis and management of cardiac conditions in the newborns. Systematic studies were conducted in various populations by using electronic cardiac auscultation and the ratio of the amplitude of first heart sound S1 to the amplitude of second heart sound S2 could provide a non-invasive assessment of cardiac activity. It has been proved that these indicators can be used to reflect the relationship between the cardiac contractility and the peripheral resistance and to evaluate the relative workload status of the left and right ventricles, respectively.Objective. The primary objective of this work was to devise some indicators based on relative values of the neonatal electronic phonocardiograms for evaluating the differences between them in newborns of different gestational age and for evaluating the neonatal cardiac heart activity.Materials and methods. 343 newborn babies of gestational age 26 to 42 weeks were examined. In the group of examined children, no structural defects of the heart and large vessels were found prenatal or after birth as well as no pathological changes were detected using traditional auscultation. The following study using electronic auscultation was performed by the digital stethoscope Thinklabs Model ds32a + at five standard listening points. The sound recording was performed on the Sony-ICD-UX71 digital voice recorder. The analysis of received phonocardiograms was carried out with the help of the developed computer program "Hearttone D". Results. The amplitude ratio of the first heart sound to the second heart sound (s1_a_max/ s2_a_max), the width ratio of the first heart sound to the second heart sound (s1_width/s2_width) of the neonates were measured, calculated and analyzed. Revealed significant differences between these indicators in newborns of different gestational age.Newborn babies with a gestational age of 33-35 weeks had significant differences in s1_a_max/ s2_a_max in the presence of a patent ductus arteriosus. Newborns with a patent ductus arteriosus had higher values of this parameter.Conclusions. There are significant differences in the electronic phonocardiograms of newborns from different gestational age groups. Newborn babies with a gestational age of 33-35 weeks had significant differences in s1_a_max/ s2_a_max in the presence of a patent ductus arteriosus. The obtained results indicate that further research is required to gain a better understanding of the electronic auscultation of the heart for the early cost-effective screening and control of the course of cardiovascular diseases in newborns.