Frequency of Pathological Electrocardiographic Findings and the Role of Electrocardiographic Screening in the First Form Pupil Population in Latvia. Summary of the Doctoral Thesis

Abstract

Standards of normal electrocardiographic finding in children used till now are based on the study of Davignon et al., which was performed in the seventies of the previous century. ECG of 2141 children was analysed within this study. Children ECG screening has not been done in Latvia yet, that is why early detection of several heart diseases – rhythm disturbances etc is not possible. The aim of the study was to determine the incidence of abnormal ECG finding and its correlation with further investigations in the population of first grade pupils in Latvia. Methods. Twelve leads electrocardiograms(ECG) were performed to randomly selected 852 first grade pupils in Latvia. Data analysis was based on the measurements, done automatically, but in case of doubts measurements those were checked visually. Further investigations were performed according to the identified pathology. Data were analysed using Microsoft Excel 2010 un SPSS 20 programmes. Results. Twelve leads electrocardiographic investigation was performed to 852 first grade pupils. Mean ECG parametrs in the investigated population was: heart rate: 90.55 (± 13,93) beats per minute, PQ interval – 131.08 (± 9.04)msec, QRS komplex – 83.62 (± 9.04) msec, QTc interval – 386.93 (± 12.40) msec, axis of QRS 70.91 (± 21.19)°, amplitude of S wave in the lead V1 – 10.52 (± 4.74) mm, amplitude of R wave in the lead V5 or V6, choosing the highest – 17.04 (± 5.33) mm. Choosed parameter for left ventricular hypertrophy SV1 + RV6 > 47 mm was found in 11 children of the investigated population. Left ventricular hypertrophy was not found in any of them by echocardiography. Arrhythmogenic right ventricular cardiomyopathy was not confirmed in a child with Epsilon wave on ECG. Eight children with bradycardia showed no significant slow-down of heart rate in Holter monitoring. The standard of normal ECG percentiles was developed, different from the one used so far. An algorithm of ECG evaluation in 7–8-year-old children was performed. Conclusions. Twelve leads ECG that was done in 852 firs grade pupils in Latvia includes representatible and informative population. It was enought for statistical analysis. There was 438 girls and 414 boys investigated. Pathological ECG foundings have a correlation with its phenothypical occurence in main population. No ECG signs of cardiomyopathies was found. It means, that investigated population was too small to diagnose those diseases. Normal ECG percentiles in the age 7-8 years was developed different from those used till now. An algorithm of ECG evaluation in 7–8-year-old children was performed. It can be useful in general practitioners and other clinicians who perform and ECG screening for 7–8 years old children.