[Heart rate variability in patients with thyrotoxicosis before and after thyroid resection].

AIM: To evaluate parameters of variation pulsometry, heart rate variability (HRV) before and after surgical treatment of patients with thyrotoxicosis.

MATERIAL AND

METHODS

Enzyme immunoassay measured blood levels of TTH and free thyroxin (T4f), HRV was traced for 5 min with variation pulsometry, frequency and time course analysis in 124 patients (37 males, 87 females, age 20-74, mean age 50.4 +/- 1.7 years) with manifest (n = 73) and complicated (n = 51) thyrotoxicosis in diffuse (n = 36) or multinodular (n = 88) toxic goiter before and 7 days after thyroid resection.

RESULTS

Aggravation of thyroxinemia with progression of thyrotoxicosis was accompanied with sympathicotonia change for vagotonia showing depletion of adaptive mechanisms in a complicated form of the disease. The weaker was sympathicotony in manifest thyrotoxicosis and the stronger was parasympathetic tension in complicated thyrotoxicosis, the higher were SDNN, RMSSD, TF, HF and LF/HF. Early after surgery (thyroid resection) thyrotoxicosis relieved with attenuation of thyroxinemia, vegetative regulation rearranged for adaptation up to achievement of vagosympathetic balance. This was more frequent in a manifest (56.1%) than in a complicated form of the disease (41.1%).

CONCLUSION

HRV provides an objective assessment of the effects of surgical treatment on the status of the autonomic nervous system.