HEART RHYTHM DISORDERS IN NEW-BORNS AND INFANTS: CLINICAL COURSE AND PERINATAL RISK FACTORS OF ARRHYTHMIAS APPEARANCE

Abstract

Clinical course, prognosis and mechanisms of separate forms of heart rhythm disorders in children differ from those in adults. Especially, it refers to new-borns and infants whose conduction system differs by functional and morphologic immaturity. In connection with it, the assessment of natural history of heart rhythm disorders, occurred in a perinatal period, and determination of risk factors of arrhythmia appearance in infants are of some interest. 88 newborns took part in the study. The patients were involved by continuous sampling technique. Risk factors, occurred in a perinatal period and potentially influenced on development of heart rhythm disorders, were assessed. In our study we took biological, gynecologic and obstetric history, data of gestation and delivery course, early and late neonatal period, early infancy, Echo, neurosonography, Holter monitoring with determination of heart rhythm variability, and determined thyroid hormonal status. Maximum specific gravity had extrasystoles – 32.4% – in the structure of idiopathic arrhythmias in infants. Heart rhythm disorders with natural history were kept at six months of life only in 5,4% of children. Persistence of arrhythmias was marked during one year only for WPW syndrome. Heart rhythm disorders are often marked significantly in children whose mothers had acute respiratory disease during the pregnancy, or if the children were born from the first pregnancy, had the signs of central nervous system damage syndromes in an early perinatal period (arrest, intracranial hypertension, convulsive disorder). Disorders of autonomic imbalance of cardiac function and peculiarities of hemodynamics of pulmonary circulation contribute significantly into appearance and persistence of all types of arrhythmias. On the whole, the prognosis of heart rhythm disorders, occurred in the perinatal period, without organic and structural changes of myocardium is favorable. The exclusion can be made for congenital atrioventricular block and some types of supraventricular tachycardia which are not responded to treatment.