Quality of life, neuro-humoral status and physical performance in adolescents with sinus tachycardia

The variety of causes, conditions and prognosis of sinus tachycardia (ST) had determined the study examining the quality of life, neurohumoral status as well as ST course in 17-year-old adolescents compared to their peers without heart rhythm disorders. The aim was to study neurohumoral status, quality of life and physical performance in adolescents of both sexes, aged 17 years with diagnosed ST during preventive examination using 24-hour ECG monitoring. Materials and methods. In the open prospective study, 165 adolescents (74 boys and 91 girls) with a mean age of 17.5 +/- 0.5 years were enrolled. 24-hour ECG monitoring showed increased heart rate >90 bpm in 12 boys and 19 girls considered themselves healthy. All the children were examined according to a program including 24-hour blood pressure monitoring, heart rate variability, serum concentrations of the main hormones, endothelin and copeptin. Health-related quality of life was measured by the SF-36 questionnaire. A physical work capacity test (PWC 170 ) on a bicycle ergometer was evaluated in an 8-month physical rehabilitation program. Results. Adolescents of both sexes with ST were hypersympathicotonic with humoral dysregulation of the sinoatrial node, grade I arterial hypertension, elevated blood levels of estradiol and osteocalcin and low renin in females. ST in adolescents was associated with reduced physical performance, the restoration of which was accompanied by ST termination. Conclusions. The examination of the 165 adolescents with the mean age of 17.5 years who considered themselves healthy has revealed 12 (16.6 %) males and 19 (22.9 %) females with ST and mean 24-hour heart rate >90 bpm. The children have been clinically diagnosed with inappropriate ST based on international classification, that were inadequate to healthy state. ST was accompanied by hypersympathicotonic type of sinoatrial node humoral dysregulation, grade I arterial hypertension in boys, abnormal pubertal development in girls with elevated blood levels of total estradiol and osteocalcin and low free renin levels, lowered levels of quality of life on role functioning of the SF-36 questionnaire. Adolescents with ST had lower performance in the PWC170 tests. The completion of the 8-week physical rehabilitation program via stationary cycling exercises has resulted in improved physical performance based on the PWC170 test from baseline levels of 8.6 +/- 1.9 kgm/min per kg body weight to 12.8 +/- 2.1 kgm /min per kg in girls (p = 0.08) and from 13.2 +/- 1.5 kgm/min to 15.9 +/- 1.6 kgm/min per kg body weight in boys (p > 0.1), that was accompanied by ST termination.