Impact of subclinical hypothyroidism treatment in systolic and diastolic cardiac function

Impacto do tratamento do hipotireoidismo subclínico na função cardíaca sistólica e diastólica

OBJECTIVE: To evaluate the effects of levothyroxine (L-T4) replacement in echocardiographic parameters of middle-aged women with subclinical hypothyroidism (SH). SUBJECTS AND METHODS: This was a randomized, double-blind, placebo-controlled study. Echocardiographic evaluation was carried out at baseline and one year after restoration of euthyroidism. Thirty-three women with SH were assigned to one of two groups (L-T4 or placebo). RESULTS: The two groups had similar basal characteristics. There was a significant deterioration of left ventricular Tei index after one year of placebo use, which differed from the effect of L-T4 replacement (+0.086 ± 0.092 vs. -0.014 ± 0.012; p = 0.047). There was also a slight reduction in cardiac output and cardiac index with placebo use, which was not different from L-T4 effect. CONCLUSION: Results suggest a positive impact of L-T4 replacement in cardiac function of middle-aged women with SH.

Hypothyroidism; thyroxine; echocardiography; Doppler; cardiovascular disease

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