Diagnostics of myocardial damage in premature newborns with transient heart disease in the early neonatal period

Abstract

Purpose. To assess frequency and severity of myocardial damage in premature infants with transient myocardial ischemia in the early neonatal period.Materials and methods. The study includes 73 newborns of a gestational age of 31–36 weeks with respiratory failure and oxygen dependence in the first 2 hours of life. Newborns are divided into groups: Group 1: classic electrocardiographic criteria of transient myocardial ischemia and an increase in the level of troponin I in the blood; Group 2: electrocardiographic criteria for transient myocardial ischemia and a normal level of troponin I; Group 3: no ECG changes and normal troponin I level. We assessed blood gases, conducted electrocardiography, determined troponin I in the blood on the 1st and 7th day of life, assesses duration of oxygen therapy in all the children.Results. Group I: troponin I concentration on the 7th day of life – 0.415 [0.222; 0.639] ng/ml, Group II – 0.073 [0.051; 0.104] ng/ml and Group III – 0.017 [0.006; 0.051] ng/ml. Transient myocardial ischemia was detected in 41% of examined patients, and destructive myocardial changes – in 21.9%. An analysis of the gas composition of blood in the first 2 hours demonstrated that there was a significant predominance of the level of bases in the children of Group I. The duration of artificial ventilation in children of Group I was 56 [3; 96] hours, exceeding the indicators of children of Group II (9 [8; 11]) by 5 times, and Group III (20.5 [13; 72]) – by 2.5 times. Also newborns in Group I experienced a maximum need for oxygen therapy through a mask.Conclusion. 21.9% of premature infants experience destructive myocardial changes against the background of transient myocardial ischemia; newborns with transient myocardial ischemia and destructive changes have a significantly more pronounced metabolic acidosis in the first hours of life and a longer need for oxygen therapy.