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Normal limits of the electrocardiogram in Indians
Peter W Macfarlane1, Suzanne M Lloyd2, Dilbag Singh3
1Institute of Cardiovascular and Medical Sciences, University of Glasgow, UK.
Journal of Electrocardiology
|May 21, 2015
Summary
This study established normal electrocardiogram (ECG) limits for South Asian Indians. The findings suggest existing Caucasian ECG criteria may be applicable to this population.
Area of Science:
- Cardiology
- Medical Diagnostics
Background:
- Establishing population-specific normal limits for electrocardiograms (ECGs) is crucial for accurate diagnosis.
- Previous ECG research has primarily focused on Caucasian populations, potentially limiting applicability to diverse ethnic groups.
Purpose of the Study:
- To determine the normal reference ranges for electrocardiogram (ECG) parameters in a healthy South Asian Indian population.
- To assess the applicability of existing ECG interpretation criteria to this demographic.
Main Methods:
- 12-lead ECGs were recorded from 963 apparently healthy South Asian Indian volunteers across three centers using identical digital electrocardiographs.
- ECG data were analyzed using the University of Glasgow ECG Interpretation Program.
Main Results:
- Significant sex-based differences were observed: males exhibited longer QRS duration and higher QRS voltages, while females had longer QT intervals.
- Age influenced QRS voltages, with younger individuals showing higher readings compared to older individuals.
Conclusions:
- The study's findings generally align with those observed in other populations.
- Existing electrocardiogram (ECG) interpretation criteria developed for white Caucasian populations appear suitable for use in South Asian Indian individuals.
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