Heart rate profile during exercise in patients with early repolarization
Serkan Cay1, Goksel Cagirci, Ramazan Atak
1Department of Cardiology, Yuksek Ihtisas Heart-Education and Research Hospital, Ankara, Turkey. cayserkan@yahoo.com
Chinese Medical Journal
|November 2, 2010
Summary
Early repolarization is linked to an altered heart rate profile during exercise, showing decreased heart rate increments and decrements. This finding may contribute to understanding sudden cardiac death risk.
Area of Science:
- Cardiology
- Exercise Physiology
Background:
- Early repolarization and abnormal heart rate patterns are risk factors for sudden cardiac death.
- The relationship between early repolarization and exercise heart rate dynamics requires further investigation.
Purpose of the Study:
- To investigate the association between early repolarization and heart rate response during exercise.
- To compare exercise heart rate profiles in individuals with and without early repolarization.
Main Methods:
- Exercise stress testing was performed on 84 subjects (44 with early repolarization, 40 controls).
- Analysis included resting heart rate, maximum heart rate, and heart rate increment and decrement.
- Statistical analysis adjusted for age and sex.
Main Results:
- Subjects with early repolarization exhibited significantly lower maximum heart rate, heart rate increment, and heart rate decrement compared to controls.
- Lower heart rate increment (<106 bpm) and decrement (<95 bpm) were strongly associated with early repolarization.
- Adjusted analysis revealed increased odds of early repolarization with lower heart rate increment (OR 2.98) and decrement (OR 7.73).
Conclusions:
- Early repolarization is associated with an altered heart rate profile during exercise.
- These exercise-induced heart rate changes in early repolarization may be implicated in sudden cardiac death risk.
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