Heart Rate Fragmentation, Ambulatory Blood Pressure, and Coronary Artery Calcification: A Population-Based Study

Area of Science:

• Cardiology
• Biomedical Engineering
• Public Health

Background:

• Ultra-rapid heart rate variability patterns, such as heart rate fragmentation (HRF), are not well understood in relation to coronary artery calcification (CAC) in the general population.
• Subclinical atherosclerosis, indicated by CAC, is a significant risk factor for cardiovascular events.

Purpose of the Study:

• To investigate the association between HRF and CAC in a general population.
• To determine if this association is independent of systolic blood pressure (SBP) levels.

Main Methods:

• Utilized data from the Shiga Epidemiological Study of Subclinical Atherosclerosis (SESSA).
• Assessed 24-hour ambulatory blood pressure monitoring for awake and asleep SBP.
• Quantified HRF using the percentage of inflection points (PIP) from 24-hour Holter monitoring.
• Measured CAC using the Agatston score from computed tomography scans.
• Employed multivariable logistic regression to analyze associations.

Main Results:

• The study included 508 participants (mean age 66.5 years), with 64% having CAC.
• Higher awake SBP (OR 1.40, 95% CI: 1.11-1.77) and asleep SBP (OR 1.28, 95% CI: 1.02-1.60) were associated with prevalent CAC.
• Higher awake PIP (OR 1.23, 95% CI: 0.99-1.54) and asleep PIP (OR 1.31, 95% CI: 1.05-1.62) were also associated with CAC.
• No significant interaction was found between PIP and ambulatory SBP regarding CAC presence.

Conclusions:

• Elevated HRF and SBP levels during sleep are independently associated with the presence of CAC in a general male population.
• HRF, particularly during sleep, may serve as a novel biomarker for subclinical coronary atherosclerosis.