The aim of the study was to analyse exercise efficiency, changes in heart rate and arterial blood pressure as well as oxygen consumption in children with the primary syndrome of mitral valve prolapse (mvps). The study included 75 children (58 girls, 17 boys) aged 7-19 years. The patients were divided into two groups: A - with prolapse of the front leaflet without mitral incompetence or with the 'trace', B - with prolapse of both leaflets and I-II°mitral incompetence. The two groups were compared with control group of healthy children with negative history of heart diseases. Attenuated heart efficiency was observed in patients with the prolapse of both leaflets and I-II°mitral valve incompetence. There was statistically significant positive correlation between the maximum exercise heart rate and double product in all the patients with mvps, while negative correlation with exercise duration, metabolic equivalent and maximum oxygen consumption index was found only in the group of patients with I-II°incompetence. Children with mvps and I-II°mitral valve incompetence ought to be subjected to periodic monitoring of exercise efficiency together with heart rate, blood pressure, RT interval and oxygen consumption.

Keywords: systolic function, Exercise Tolerance, Mitral Valve Prolapse