Investigation of Normal Electrocardiographic Indices in ۵۰۰ Healthy Adult Persons

In all medical centers electrocardiography is one of the first steps in the evaluation of patients suspected of heart disease. It is therefore clear that distinguishing normal from pathologic patterns in electrocardiography is of utmost importance. The aim of this descriptive and analytical study was to determine the normal electrocardiographic indices in all leads and to investigate the influence of age and sex on these indices. For this purpose ۵۰۰ healthy subjects were selected with the simple sampling method. After obtaining an electrocardiography and calculating the indices, the results were analyzed yielding the following results: Since in most cases P wave was negative in DIII and V۱ leads and T wave in V۱ and avF we can consider these negative waves as normal. At least in certain leads the great majority of electrocardiographic indices had significant relationships with age and sex. Most notably QRS interval which increasesd with age in all leads and QT interval that was longer in women than in men in all leads.