Exogenous subclinical hyperthyroidism: effect on the cardiovascular system.

Objective: To evaluate the effects of exogenous subclinical hyperthyroidism on left ventricular structure and function.

Material And Method: Twenty-three patients of both sexes, aged 27 to 70 years, with a diagnosis of exogenous subclinical hyperthyroidism (serum thyroid-stimulating hormone [TSH] ≤ 0.4mU/ml and normal free thyroxine [FT4]) were evaluated.