Heart rate variability changes in children after cardiac transplantation

Area of Science:

• Cardiology
• Pediatrics
• Medical Technology

Background:

• Heart rate variability (HRV) analysis is a precise, non-invasive method for assessing cardiovascular function.
• HRV provides sensitive insights into the autonomic nervous system's control over the heart.

Purpose of the Study:

• To investigate changes in time-domain heart rate variability (HRV) parameters in pediatric patients following cardiac transplantation.
• To compare HRV metrics in transplanted children with healthy control groups.

Main Methods:

• Analyzed five HRV parameters (NN intervals, SD, pNN50, rMSSD, triangular index) from 24-hour Holter monitoring.
• Included two pediatric cardiac transplant recipients (ages 5 and 14) and two control groups of healthy children (ages 5-7 and 14-16).
• Compared HRV parameters against percentile ranges from healthy individuals.

Main Results:

• Reduced rMSSD, pNN50, and triangular index (below 10th percentile) observed in the 14-year-old transplant recipient.
• Lower rMSSD and SD (below 10th percentile) noted in the 5-year-old transplant recipient.
• Both patients exhibited decreased total HRV and parasympathetic activity parameters.

Conclusions:

• Cardiac transplantation in children is associated with diminished heart rate variability, particularly affecting parasympathetic activity.
• The underlying mechanisms of altered cardiac innervation post-transplantation require further investigation.
• Future studies will incorporate frequency-domain HRV analysis to provide a more comprehensive understanding.