Comparisons and correlations of the electrocardiography changes regarding the functional features before, during and immediately after the treadmill test with athletes

Abstract

The need for cardiovascular screening in order to timely detect and diagnose the morphological and functional changes of the heart, which occur as a result of doing sport actively, and thus to avoid the occurrence of sudden cardiac death, is generally accepted. To achieve the objectives of the study, two non- invasive diagnostic methods for cardiovascular evaluation were used: electrocardiography (ECG) and the Bruce protocol test. The purpose of this study was to determine and examine the relationship of ECG changes to functional characteristics before, during, and/or immediately after exercise testing. This cross- sectional study conducted during 2016/2017 involved 285 athletes aged 9 to 38, of both sexes. They were all given a 12-channel electrocardiogram (ECG) at rest, after which personal, family and sports history and anamnesis were given, followed by a Bruce protocol test and functional parameters were examined (symptoms, metabolic equivalents, METs, test duration, exercise capacity-VO2 max, rhythm disturbance, heart rate, heart rate reserve and recovery, chronotropic incompetence (CI), systolic and diastolic blood pressure). According to ECG changes and in accordance with international recommendations for its interpretation, athletes were divided into 4 groups: with normal, physiological, borderline or abnormal ECG findings. The results showed a significant positive connection between abnormal ECG and the occurrence of rhythm disturbance during the exercise test (r = 0.119; p = 0.045); Cardiovascular capacity expressed in (METs) compared to respondents with normal ECG was significantly higher in those with physiological ECG changes (p = 0.003), HR reserve percentage was lowest among athletes with abnormal ECG, and CI had the highest percentage. It can be concluded that an athlete with borderline, abnormal, and possibly physiologically assessed ECG should undergo further evaluation.