Supraventricular arrhythmias and the relation to thyroid dysfunction in a group of Syrian patients.

A group of 104 patients with supraventricular arrhythmias were classified according to the etiology. Twelve patients had serum levels of thyroid hormones considerably above and one patient had levels below the limits of normal reference range for our population. Only two of the hyperthyroid patients had many of the signs and symptoms of thyrotoxicosis, while the other 10 patients presented with only the arrhythmias. Three patients had some cardiac lesion together with the hyperthyroidism. Lastly, the main arrhythmia in those hyperthyroid patients was auricular fibrillation, (58%).