Hypothyroid children have significantly prolonged Tpe intervals compared to healthy controls, indicating increased heterogeneity in ventricular repolarization.
Cohort (n=64)
No
Does levothyroxine therapy improve ventricular repolarization and heart rate variability in pediatric patients with clinical hypothyroidism?
Pediatric hypothyroidism is associated with prolonged ventricular repolarization (Tpe interval) which normalizes after 3 months of levothyroxine therapy, highlighting the importance of early treatment to maintain cardiac electrical stability.
Effect estimate: null (95% CI null)
Absolute Event Rate: 58.07% vs 53.8%
p-value: p=0.039
Abstract To compare ventricular repolarization and heart rate variability in hypothyroid and healthy children and to assess the effects of levothyroxine therapy on cardiac electrophysiological and autonomic parameters. This study investigated ventricular repolarization parameters and heart rate variability (HRV) in hypothyroid children (5–12 years) compared with age-matched healthy controls and patients before and after thyroxine treatment. This study included 64 participants divided into hypothyroid and healthy groups (32 each). Parameters such as the Tpe interval, QT interval, and HRV indices were measured via standard electrocardiographic and HRV analysis techniques. Thyroid hormone levels were measured. Post treatment measurements were also performed on hypothyroid children following 3 months of levothyroxine therapy. Hypothyroid children presented significantly prolonged Tpe intervals (58.07 ± 9.21 ms vs. 53.80 ± 8.89 ms, p = 0.039), reflecting increased heterogeneity in ventricular repolarization. HRV analysis revealed decreased parasympathetic modulation (e.g., lower RMSSD and pNN50 values) in hypothyroid participants. Posttreatment improvements in HRV indices and thyroid hormone levels correlated with normalization of cardiac electrophysiological parameters. This study highlights that even mild thyroid dysfunction in children can subtly disrupt cardiac electrical stability and autonomic balance which may increase the risk of arrhythmia in this population. Timely thyroxine therapy not only restores thyroid levels but also powerfully rebalances the electrical and autonomic balance of the heart. These findings reaffirm the critical need for early detection and proactive treatment of pediatric hypothyroidism to safeguard lifelong cardiovascular health.
Dhakar et al. (Thu,) conducted a cohort in Pediatric clinical hypothyroidism (n=64). Levothyroxine therapy vs. Healthy children was evaluated on Tpe interval (null, 95% CI null, p=0.039). Hypothyroid children have significantly prolonged Tpe intervals compared to healthy controls, indicating increased heterogeneity in ventricular repolarization.