Correlation between free thyroxin levels and left ventricular ejection fraction in Graves' disease (preliminary study).

Aim: to determine the correlation between free thyroid hormone level and left ventricular ejection fraction in newly diagnosed Graves' patients.

Methods: this is a preliminary study with an initial cross-sectional design using free thyroxine level as a parameter of thyroid hormone state and left ventricular ejection fraction (LVEF) as a parameter of left ventricular systolic function. Free thyroxine level was measured in the laboratory and the LVEF was assessed by Simpson's methods of echocardiography study.

Results: ten patients (7 men and 3 women; age 18-52 years old) were studied. Their average of fT4 was 5.75 (SD 0.96) ng/dL and their average of LVEF was 70.57 (SD 4.50)%. There was positive correlation coefficient between free thyroxine level and left ventricular ejection fraction (r=0.711, p=0.021) in newly diagnosed Graves' patients.

Conclusion: in this study strong positive correlation was found between free thyroxine (fT4) and left ventricular ejection fraction (LVEF) in newly diagnosed Graves' patients.