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Effect of levothyroxine on cardiac function in children with subclinical hypothyroidism: A quasi-experimental study
Nasrin Banu Rupani1, Morteza Alijanpour2, Kazem Babazadeh2
1Student Research Committee, School of Medicine, Babol University of Medical Sciences, Babol, Iran.
Insights
Levothyroxine treatment improved cardiac function in children with subclinical hypothyroidism. Key parameters like ejection fraction and fractional shortening showed significant improvements after treatment.
Area of Science:
- Pediatric Endocrinology
- Cardiology
- Thyroid Disorders
Background:
- Thyroid hormones are crucial for overall bodily function, including cardiac health.
- Subclinical hypothyroidism in children can impact various organs, necessitating evaluation of cardiac effects.
Purpose of the Study:
- To assess the impact of levothyroxine treatment on cardiac function in pediatric patients diagnosed with subclinical hypothyroidism.
Main Methods:
- A quasi-experimental study involving 30 children (ages 4-12) with subclinical hypothyroidism.
- Echocardiographic measurements of cardiac parameters (EF, FS, E/E', MPI, LVEDD, LVESD) were taken before and after 6 months of levothyroxine therapy.
Main Results:
- Levothyroxine significantly improved ejection fraction (EF) and fractional shortening (FS).
- Myocardial performance index (MPI) and left ventricular end-diastolic diameter (LVEDD) also showed significant improvements.
- No significant change was observed in the E/E' ratio, and left ventricular end-systolic diameter (LVESD) showed a non-significant decrease.
Conclusions:
- Levothyroxine therapy demonstrates potential to enhance cardiac functional parameters in children with subclinical hypothyroidism.
- These findings suggest a beneficial role for early thyroid hormone replacement in pediatric subclinical hypothyroidism affecting cardiac health.
Background:
Because of the importance of thyroid function and its effect on different organs, such as the heart, this study was aimed to evaluate the effect of levothyroxine on cardiac function in children with subclinical hypothyroidism.
Methods:
This quasi-experimental study was performed on children aged 4-12 years old with diagnosis of subclinical hypothyroidism in Amirkola Children's Hospital during 2018-2019. Cardiac functional parameters, including ejection fraction (EF), fractional shortening (FS), ratio of early filling velocity to early diastolic mitral annulus velocity (E/E'), myocardial performance index (MPI), left ventricular end-diastolic diameter (LVEDD), and left ventricular end-systolic diameter (LVESD), were measured by echocardiography at baseline and 6 months after levothyroxine treatment.
Results:
Out of the 30 subjects, 19 (63.3%) were boys and 11 (36.7%) were girls. The mean age was 6.60±2.13 years old. The mean EF index was 63.13±3.01 percent before treatment, which increased to 69.07±4.50 percent after treatment (p<0.001). Also, the mean FS was 31.83±1.62 percent before treatment, which improved to 35.10±1.13 percent after treatment (p<0.001). The mean MPI was 0.28±0.02 before treatment, which increased to 0.33±0.03 after treatment (p<0.001). On the other hand, no significant difference was found in the mean E/E' before and after treatment. The mean LVEDD decreased from 3.47±0.46 cm before treatment to 3.05±0.40 cm after treatment (p<0.001), whereas LVESD non-significantly decreased after treatment versus before treatment.
Conclusion:
The results showed that treatment with levothyroxine may improve cardiac functional parameters in children with subclinical hypothyroidism.
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