Study of P wave indices in sinus rhythm and tachycardia

P Wave Indices (PWI) have been proved to be a potential marker in determination of various heart conditions. This study shows the extended implications drawn from these indices for determination of tachycardia and encompassing arrhythmias. ECGs were recorded from 50 Sinus Rhythm (SR) and 25 Sinus Tachycardia (ST) volunteers using EDAN PC ECG machine at the paper speed of 25 mm/s and gain of 10 mm/mV. Higher P wave axis (o) and amplitude (μV) values were found in ST (62 ± 15.38; 73 ± 15.32) than SR (49 ± 17.90; 63 ± 7.93) and differed significantly between the groups with P <; 0.05. P wave duration (ms) (SR; ST: 96 ± 9.18; 96 ± 10.01) and PR Interval (ms) (SR; ST: 138 ± 17.60; 135 ± 18.25) did not differ significantly with P > 0.05 between the groups. However, P wave Dispersion (PD) were higher in SR (20 ± 11.32 ms) compared to ST (13 ± 10.01 ms). In ST condition, higher heart rate lead to an increased mean P wave axis and amplitude compared to SR. Higher PPI variability was observed within the limits in SR. PD for both the groups was within the normal limits. This study highlights the variation in PWI in different heart conditions. Further clinical analysis is needed to study the prevalence of Atrial Fibrillation (AF) in tachycardia conditions.