Related Experiment Video

Updated: Jan 31, 2026

Autonomic Function Following Concussion in Youth Athletes: An Exploration of Heart Rate Variability Using 24-hour Recording Methodology
05:48

Autonomic Function Following Concussion in Youth Athletes: An Exploration of Heart Rate Variability Using 24-hour Recording Methodology

Published on: September 21, 2018

10.6K

Evaluation and correlation of heart rate variability and ventricular repolarization parameters in an Indian pediatric

Divyam Dhakar1, Himani Ahluwalia1, K R Meena2

  • 1Department of Physiology , Vardhman Mahavir Medical College and Safdarjung Hospital , New Delhi, India.

Scientific Reports
|January 29, 2026
PubMed

Insights

Pediatric hypothyroidism prolongs ventricular repolarization and reduces heart rate variability (HRV) in children. Levothyroxine therapy effectively restores cardiac electrical and autonomic balance, crucial for cardiovascular health.

Area of Science:

  • Pediatric Endocrinology
  • Cardiology
  • Autonomic Neuroscience

Background:

  • Thyroid dysfunction in children can impact cardiovascular function.
  • Ventricular repolarization and heart rate variability (HRV) are key indicators of cardiac health.
  • Hypothyroidism may affect cardiac electrophysiology and autonomic nervous system balance.

Purpose of the Study:

  • To compare ventricular repolarization and HRV in hypothyroid and healthy children.
  • To assess the effects of levothyroxine therapy on cardiac parameters in pediatric hypothyroidism.
  • To investigate the relationship between thyroid hormone levels and cardiac function.

Main Methods:

  • Electrocardiographic and HRV analysis were used to measure Tpe interval, QT interval, and HRV indices.
  • 64 children (5-12 years) were included: 32 hypothyroid and 32 healthy controls.
  • Measurements were taken before and after 3 months of levothyroxine therapy in the hypothyroid group.

Main Results:

  • Hypothyroid children showed significantly prolonged Tpe intervals, indicating increased ventricular repolarization heterogeneity.
  • Reduced parasympathetic modulation (lower RMSSD, pNN50) was observed in hypothyroid children.
  • Levothyroxine therapy improved HRV indices and normalized cardiac electrophysiological parameters, correlating with improved thyroid hormone levels.

Conclusions:

  • Pediatric hypothyroidism, even mild, can disrupt cardiac electrical stability and autonomic balance, potentially increasing arrhythmia risk.
  • Levothyroxine therapy is effective in restoring thyroid levels and rebalancing cardiac electrical and autonomic function.
  • Early detection and treatment of pediatric hypothyroidism are vital for long-term cardiovascular health.

Keywords:
Child healthHeart rate variabilityLevothyroxine therapyPediatric hypothyroidismVentricular repolarization

More Related Videos

Implementation of Non-invasive Point of Care Transient Elastography for Evaluation of Liver Disease in Pediatric Populations with Cystic Fibrosis05:56

Implementation of Non-invasive Point of Care Transient Elastography for Evaluation of Liver Disease in Pediatric Populations with Cystic Fibrosis

Published on: August 29, 2025

572
Candidate Gene Testing in Clinical Cohort Studies with Multiplexed Genotyping and Mass Spectrometry05:53

Candidate Gene Testing in Clinical Cohort Studies with Multiplexed Genotyping and Mass Spectrometry

Published on: June 21, 2018

10.7K

Related Concept Videos

Distributions to Estimate Population Parameter01:26

Distributions to Estimate Population Parameter

The accurate values of population parameters such as population proportion, population mean, and population standard deviation (or variance) are usually unknown. These are fixed values that can only be estimated from the data collected from the samples. The estimates of each of these parameters are sample proportion, the sample mean, and sample standard deviation (or variance). To obtain the values of these sample statistics, data are required that have particular distribution and central...
5.1K
Correlation and Causation01:27

Correlation and Causation

Statistical tests can calculate whether there is a relationship, or correlation, between independent and dependent variables. An indirect relationship of the variables signifies a correlation, while a direct relationship shows causation. If it is determined that no connection exists between the variables, then the correlation is a coincidence.
Correlation versus Causation
If the dependent variable increases or decreases when the independent variable increases, there is a positive or negative...
42.5K
Rheumatic Heart Disease II: Clinical Manifestations and Diagnostic Studies01:22

Rheumatic Heart Disease II: Clinical Manifestations and Diagnostic Studies

The key clinical manifestations of Rheumatic heart disease (RHD) include several distinct cardiac symptoms.Carditis, a hallmark of acute rheumatic fever, involves inflammation of the heart's endocardium, myocardium, and pericardium. Chronic RHD often results from recurrent episodes of carditis. Its symptoms include the following:Murmurs are caused by valvular damage, especially to the mitral and aortic valves. Mitral stenosis or regurgitation is common, with characteristic heart murmurs...
581
Regulation of Heart Rates01:31

Regulation of Heart Rates

The regulation of heart rate is a complex process controlled by the autonomic nervous system (ANS), hormonal influences, and intrinsic cardiac mechanisms. The ANS has two main components: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS).
The SNS increases heart rate through the release of norepinephrine and epinephrine, which act on beta-1 adrenergic receptors in the heart. This action increases the rate of depolarization in the sinoatrial (SA) node, the heart's...
3.9K
Correlations02:20

Correlations

Correlation means that there is a relationship between two or more variables (such as ice cream consumption and crime), but this relationship does not necessarily imply cause and effect. When two variables are correlated, it simply means that as one variable changes, so does the other. We can measure correlation by calculating a statistic known as a correlation coefficient. A correlation coefficient is a number from -1 to +1 that indicates the strength and direction of the relationship between...
35.9K
Factors Influencing Heart Rate01:30

Factors Influencing Heart Rate

The heart rate, or pulse rate, is a vital indicator of cardiovascular health. It reflects the number of times the heart beats per minute. Various physiological and environmental factors influence heart rate, increasing or decreasing cardiac output. Understanding these factors is crucial for assessing heart function and identifying potential health issues.
Let us explore the significant factors affecting heart rate, including age, body temperature, posture, acute pain, chemical influences,...
6.3K