1Assistant Professor, Department of Medicine, BPS GMCH, Khanpur kalan
2Associate Professor Department of Paediatrics, BPS GMCH, Khanpur kalan
3MBBS Final Year Student, Department of Paediatrics, BPS GMCH, Khanpur kalan
*Corresponding Author: Dr. Manoj Rawal Associate Professor, Department of Paediatrics, BPS GMCH, Khanpur kalan-131305 Phone No. 9896006383, E-mail: drmanojrawal@yahoo.com
Online published on 16 March, 2018.
The QT interval represents the time period between the depolarization of the ventricle and the end of repolarisation. A prolonged QT interval is an antecedent for dangerous arrhythmias and sudden cardiac death. Since QT interval varies with heart rate corrected QT interval (QTc) and QT dispersion (QTd) are used as parameter to compare QT interval. It has been found that cardiovascular risk factors affect the QT interval in middle aged individuals. Since these risk factors appear early in life, screening for the effect of these factors on the QT interval should begin in asymptomatic young individuals.
The aim of our study was to estimate the prevalence of an elevated QTc and QTd interval in apparently asymptomatic young individuals. Also these intervals were compared with cardiovascular risk factors like body mass index and central obesity.
A case-control study was designed which included the students of BPSGMC(W) Khanpur Kalan, Sonepat.100 students were randomly selected and were divided into 2 groups of 50 students with a normal BMI AND 50 overweight students. Their ECGs were recorded and QTC and the QTd were calculated. The intervals of both groups were compared and also correlated with BMI and waist-hip ratio using standard statistical software SPSS version 22.
The prevalence of an elevated QTc and QTd was found to be 1% and 0% respectively. It was observed that the QTc interval was significantly higher in the overweight group (QTc=409.4200±16.989) than in the normal group (QTc=401.4600±14.13; p=0.021). Also a positive correlation was found between waist circumference and QTd (r=0.062, p=0.012) and BMI and QTd(r=0.049, p=0.027). A significant correlation was found between QTc and waist-hip ratio(r=0.055, p=0.019).
The present study suggests QT interval is a simple, inexpensive method to detect the impact of cardiovascular risk factors in asymptomatic young adults and suggest lifestyle modifications for primary prevention of cardiovascular disease later in life.
Corrected QT interval (QTc), QT dispersion (QTd), Body mass index, Waist circumference, Waist-hip ratio
