[HEART RATE VARIABILITY: THE AGE-OLD TOOL STILL REMAINS CURRENT]

Area of Science:

• Cardiology
• Autonomic Nervous System Research
• Biomedical Signal Processing

Background:

• Heart rate variability (HRV) quantifies heart-brain interactions and autonomic nervous system (ANS) activity.
• Originating in the 18th century, HRV analysis is integral to electrocardiogram (ECG) development and understanding physiological regulation.
• HRV reflects autonomic balance, impacting blood pressure, respiration, and vascular tone.

Purpose of the Study:

• To highlight the diagnostic and prognostic value of HRV metrics in cardiovascular health.
• To emphasize the clinical utility of short-term HRV recordings as a practical alternative to 24-hour monitoring.
• To explore the role of HRV in risk stratification for conditions like heart failure and arrhythmias.

Main Methods:

• Utilizing time-domain (e.g., SDNN), frequency-domain (e.g., High Frequency), and non-linear analysis of HRV.
• Comparing the accuracy of short (5-minute) and ultra-short (<5-minute) HRV recordings against traditional 24-hour assessments.
• Correlating HRV metrics with clinical outcomes, including morbidity, mortality, and specific cardiac events.

Main Results:

• Reduced SDNN after acute coronary events correlates with increased mortality and ventricular arrhythmias.
• Higher non-linear HRV indices post-acute coronary event are linked to all-cause mortality.
• Short-term HRV measurements demonstrate accuracy comparable to 24-hour recordings, offering greater practicality.

Conclusions:

• HRV analysis, particularly with short recordings, provides a practical and accurate method for assessing autonomic function.
• HRV metrics serve as valuable tools for risk stratification and early diagnosis of cardiovascular diseases such as heart failure and atrial fibrillation.
• HRV assessment aids in predicting patient outcomes following acute cardiac events and in pediatric populations with myocarditis.