Background:
We aimed prospectively investigate the laboratory and electrocardiographic parameters (hearth
rate, QRS, QT, QTc, Tpe, Tpe/QTc, arrhythmia prevalance) in patients with graves disease before and after antithyroid
therapy.
Methods:
71 patients (48 female, 23 male), age between 18-50 (mean±SD: 36.48±12.20 ) with GD were included into the
study. Patients treated with antithyroid therapy (thionamids and/or surgical therapy) to maintain euthyroid status. Patients
were examined in terms of electrocardiographic parameters before and after the treatment.
Results:
Mean TSH, free thyroxin (fT4) and tri-iodothyrionine (fT3) levels of all patients were 0.005±0.21, 3.27± 1.81,
11.42±7.44, respectively. While 9 patients (group 2) underwent surgical therapy, had suspicious of malignant nodule or
large goiter and unresponsiveness to medical treatment; the other patients (n=62, group 1) were treated with medical
therapy. Patients with surgical therapy had more increased serum fT4 (p=0.045), anti-thyroglobulin value (p=0.018) and
more severe graves orbitopathy (n=0.051) before treatment when compared to medical therapy group. Baseline Tpe duration
and baseline Tpe/QTc ratio and frequency of supraventricular ectopic beats were found to be significantly higher in group 2
when compared to group 1 (p=0.00, p=0.005). Otherwise baseline mean heart rate, QRS duration, QTc values of both
groups were similar. Although the patients became their euthyroid status, group 2 patients had still suffered from more
sustained supraventricular ectopics beats than group 1.
Conclusion:
Distinct from medical treatment group, surgical treatment group with euthyroidism at least 3 months had still
suffered from an arrhythmia (Tpe, Tpe/QTc, supraventricular and ventricular ectopic beats).
