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Effective ECG reference ranges for Northern Thai people
Piyapong Khumrin1, Pratya Srisuwan2, Wongsapat Lertprayoonmit2
1Department of Physiology, Faculty of Medicine , Chiang Mai University , Chiang Mai , Thailand.
Insights
Electrocardiogram (ECG) reference ranges vary significantly with age and gender. This study establishes specific ECG normal ranges for the Northern Thai population, highlighting the need for tailored diagnostic criteria.
Area of Science:
- Cardiology
- Medical Diagnostics
- Population Health
Background:
- Electrocardiogram (ECG) values are crucial for arrhythmia classification.
- Standard ECG criteria may not apply universally across diverse patient demographics.
- Age, gender, and race significantly influence ECG measurements.
Purpose of the Study:
- To establish reference ranges for normal ECG parameters in the Northern Thai population.
- To investigate the impact of age and gender on ECG values within this specific demographic.
- To provide data for refining diagnostic criteria for cardiovascular conditions in Northern Thailand.
Main Methods:
- Analysis of 12,993 normal ECG records from 9,853 Northern Thai patients.
- Data collection occurred between May 2013 and February 2014.
- Utilized data from Maharaj Nakorn Chiang Mai Hospital.
Main Results:
- Heart rate decreased with age; PR interval and QTcB increased with age in both genders.
- Normal heart rate ranges were found to be lower than standard intervals.
- QRS duration remained stable across age groups but was longer in males; QRS axis shifted leftward with age.
Conclusions:
- ECG trends in Northern Thais largely align with other populations but show distinct variations.
- Specific adjustments to ECG criteria based on age and gender are recommended for Northern Thai patients.
- This research supports the development of more precise, population-specific diagnostic tools.
Background:
The numerical values and ranges of the ECG are used as criteria for classifying types of arrhythmia. However, one criterion cannot be generically applied for all patient groups. Several studies have shown that age, gender, and race are the major key factors which produce variations in ECG values.
Methods:
From May 2013 to February 2014, we collected 12 993 normal ECG data from 9853 Northern Thai patients at Maharaj Nakorn Chiang Mai Hospital, Chiang Mai, Thailand, to analyse their ECG reference ranges.
Results:
The results showed that the average heart rate decreased, while the PR interval and QTcB increased with increasing age in both genders. The normal range of heart rate was lower than the standard interval. QRS duration was stable in all age groups but longer in males than females. QRS axis deviated to the left with increasing age. SV1+RV5 amplitude slightly changed in both genders, but the upper limit crossed over the criteria of ventricular hypertrophy.
Conclusions:
We observed that the general trend of data was mainly similar to that found in other studies in Chinese, American, and African populations. However, some minor differences should be considered specifically for the Northern Thai population. Flexible criteria on conditions depending on age and gender should be adjusted for Northern Thai patients according to the results of this research.
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