The Evaluation of Diastolic Dysfunction with Tissue Doppler Echocardiography in Women with Subclinical Hypothyroidism and the Effect of L-Thyroxine Treatment on Diastolic Dysfunction: A Pilot Study

Abstract

Background. Subclinical hypothyroidism (SH) predominantly affects women. The necessity of treatment in SH is controversial. Objective. We aimed to investigate the response of diastolic dysfunction to thyroid hormone replacement therapy (THRT) in women. Methods and Results. Twenty-two female subjects with SH and 20 euthyroid female controls were enrolled. Baseline and follow-up biochemical, hormonal, and echocardiographic evaluations were performed. Repeat echocardiograms were performed three months after the achievement of a euthyroid status with THRT. Mean baseline myocardial performance index (MPI) was 0.27 ± 0.08 in the SH group, and 0.22 ± 0.06 in the control group (P = 0.03). MPI did not change significantly after THRT. Pulsed-wave Doppler findings were not different among the groups. However, tissue Doppler-derived mitral annular E' velocities were significantly lower in the SH group. A moderate but significant improvement was observed in E' velocities after THRT (13.2 ± 3.87 versus 14.53 ± 2.75, P = 0.04). We also observed left ventricular concentric remodeling in SH patients which was reversible with THRT. Conclusions. Tissue Doppler echocardiography may be a useful tool for monitoring the response of diastolic dysfunction to thyroid hormone replacement therapy in patients with SH. Our findings suggest that THRT may reverse diastolic dysfunction in women with SH.

The effect of levothyroxine treatment on left ventricular function in subclinical hypothyroidism

“…A study by Erkan and cols. (33) showed results similar to ours. Therefore, a longer euthyroid state or more aggressive treatment for lowering TSH may be required to achieve a statistically significant increase in the E/A ratio, after treatment.…”

The effect of L-thyroxine treatment on left ventricular functions in children with subclinical hypothyroidism

“…Previously, Erkan et al 16 found that in adults with SH L-T4 replacement did not cause any significant change in LVESD and LVEDD. In a study involving 196 children and 72 adults, Nidorf et al 38 reported that height was the best predictor of LV end-diastolic dimension and LV length.…”

“…It is well known that cardiac function is impaired in adults and children with overt hypothyroidism and it can be reversed by L-T4 treatment 24–27. Several adult studies have recently shown that patients with SH had impaired myocardial contractility11 12 28–32 and diastolic dysfunction,13 28 33 which may also be reversed by L-T4 treatment 5 6 11–13 15 16. In the literature, only two studies evaluating cardiac functions of children with SH, which also have Down syndrome and obesity, are present 34 35.…”

“…Thyroid disorders cause changes in cardiac contractility, myocardial oxygen consumption, cardiac output and blood pressure 6. Impaired myocardial contractility in overt hypothyroidism7–9 and left ventricular (LV) diastolic dysfunction in adults with SH,10–15 as well as beneficial effects of thyroid hormone replacement on systolic and diastolic functions in adults with SH,5 13 15 16 has been documented; however, the presence of similar alterations in otherwise healthy (normal weight and non-syndromic) children with SH is still under debate.…”

Abnormal thyroid function predicts mortality in patients receiving long-term peritoneal dialysis: A case-controlled longitudinal study

“…In our study, free T4 levels were inversely correlated with CRP, and higher free T4 levels showed an insignificant trend towards depressed LVEF; a finding different from the results of others studies of L-thyroxine supplement in subclinical hypothyroidism. 21,22 It is surprising that we found that a much higher mortality was caused by septic shock (66.7%) than cardiovascular events (20%). In another large retrospective study, immediate cause of death from cardiovascular events accounted for 41.2% and peritonitis was directly implicated in 15.2% of the overall deaths.…”