Intermittent heart rate-dependent early repolarization pattern (J-point ST elevation) demonstrated on Holter
1Emeritus Professor, The Hebrew University of Jerusalem, Jerusalem, Israel. sh_stern@netvision.net.il.
Cardiology Journal
|August 31, 2013
Summary
Early repolarization (ER) patterns, identified by J-point ST elevation, are often intermittent. This study found ER commonly appears at lower heart rates and disappears as heart rate increases, highlighting its dynamic nature.
Area of Science:
- Cardiology
- Electrophysiology
Background:
- Early repolarization (ER) is typically diagnosed using resting 12-lead ECG.
- The diagnostic criteria usually involve J-point ST segment elevation.
Purpose of the Study:
- To investigate the occurrence and characteristics of the early repolarization pattern on 24-hour Holter recordings.
- To determine the relationship between heart rate and the presence of the ER pattern under physiological conditions.
Main Methods:
- Analysis of 24-hour Holter recordings from 9,200 consecutive individuals.
- Evaluation of J-point ST elevation (≥ 1 mm in ≥ 2 leads, lasting ≥ 3 min) across various heart rates.
- Correlation of ER pattern appearance/disappearance with heart rate fluctuations.
Main Results:
- The ER pattern was observed in 4.9% of individuals (410 out of 9,200).
- In 93.1% of those with ER, the pattern was intermittent, predominantly occurring at heart rates below approximately 70 beats/min.
- The ER pattern typically disappeared as heart rate increased above 75 beats/min and reappeared upon slowing.
- Only 6.9% of individuals with ER showed the pattern consistently at higher heart rates.
Conclusions:
- The early repolarization pattern is frequently dynamic and heart rate-dependent.
- ER observed on a resting ECG at a slow heart rate may not be present during periods of increased heart rate.
- Absence of ER on a 12-lead ECG at a higher heart rate does not exclude its transient appearance when heart rate decreases.
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