[Effects of stress and exercise on rhythm activity of the heart and state of adrenergic regulation in patients with neurocirculatory dystonia].

Responses of healthy subjects and patients with a cardiac type neurocirculatory dystonia (NCD) to exercise and stress were evaluated. Stress was ascertained to cause a higher enhancement of catecholamine excretion than exercise. In patients with NCD, resting adrenaline (A) excretion was increased by 50%, whereas the noradrenaline (NA) one remained unchanged. The A/NA ratio showed a more than 1.5-fold increase. A stress-induced rise in NA excretion was 4 times higher in NCD patients than in healthy subjects. In the patients, resting dopamine (D) excretion was lower and the D/A + NA ratio was decreased both at rest and during exercise. In NCD the higher adrenergic response to stress was followed by the occurrence of arrhythmias in more than a half of the patients. The healthy subjects and the patients with NCD developed no arrhythmias during exercise. It has been suggested that changes in adrenergic control and associated arrhythmias are caused by dysfunction of the stress-limiting systems in NCD.