- : Ms Word, Ms Word Format
- : 80 Pages
- : ₦3000
- : 1-5 Chapters
- Click to DOWNLOAD Materials
THE ELECTROCARDIOGRAM PATTERN IN APPARENTLY NORMAL SCHOOL AGE CHILDREN IN ZARIA
Abstract
Statement of the problem: The electrocardiogram is a readily accessible tool for assessing cardiac
function, whose interpretation is age-dependent. Race and sex have an influence on
electrocardiographic variables. The interpretation of paediatric electrocardiograms locally is based
on normograms developed for Caucasian children.
Aim: This study aimed to determine the electrocardiographic pattern of school-aged children in
Zaria, to compare findings with established reference values and to evaluate the correlation with
age and anthropometry.
Methodology: This cross-sectional study was carried out in Zaria between 22nd, November 2014
and 6th, February 2015. The electrocardiograms of 587 apparently normal primary school children
(284 males and 303 females; M: F ratio = 1:1.1) aged 6 – 12 years, selected by multistage random
sampling method were interpreted manually.
Results: Sinus rhythm occurred in 88% of the study population while the remaining 12% exhibited
sinus arrhythmia. The incidence of sinus arrhythmia increased significantly with increasing age.
The median heart rates ranged from 90 to 100 beats per minute across the ages. There was a
significant negative correlation of heart rate with age (ρ = -0.14), height (ρ = -0.16) and BMI (ρ =
-0.14) all with p <0.05.
The P wave amplitude showed a significant positive correlation with age (ρ = 0.12, p <0.05). The
median P wave axis ranged between +40o and +60o, the boys having wider values than the girls. It
showed a significant negative correlation with age, ρ being – 0.12, p < 0.05.
The mean QRS axis showed a leftward shift with increasing age and had significant negative
correlation with age and height with ρ of – 0.21 and – 0.13, respectively, with p < 0.05. The QT duration had positive correlation with age (ρ = 0.18), weight (ρ = 0.27), height (ρ = 0.25) and BMI
(ρ = 0.21), while the QTc duration had a positive correlation with weight (ρ = 0.11) all with p <
0.05.
The tallest median R wave amplitudes were in V4. The R wave in V2 demonstrated significant
negative correlation with age (ρ = -0.11), weight (ρ = -0.15), height (ρ = -0.14) and BMI (ρ = 0.14)
all with p < 0.05.
S wave of V4 also showed significant negative correlation with weight (ρ = -0.13), height (ρ = –
0.13) and BMI (ρ = -0.12) with p < 0.05.
The median T wave axis ranged from +40o to +55o and had significant negative correlation with
age, weight and height, ρ being – 0.13, – 0.14, and – 0.13 respectively, with corresponding p < 0.05.
The T wave in Leads V1 and V2 showed significant positive correlation with age, weight and height
(and BMI for V2 with ρ = 0.13, p < 0.05). For V6, it showed small positive correlation with height
(ρ = 0.13) and BMI (ρ = 0.11) with p < 0.05.
Conclusion: ECG pattern of apparently normal Zaria school children was described. It shows a
lack of consistent uniformity with other Nigerian studies. Significant but weak correlations are
noted between anthropometric and ECG variables. These do not proffer a strong argument for
considering anthropometry as a confounder in evaluating ECG variability in these children.