Exaggerated amplitude and peak location of Ta wave in tachycardia as an indicator for atrial disorders

Arya Bhardwaj1, Bala Chakravarthy Neelapu2, Sivaraman Jayaraman1
1National Institute of Technology Rourkela, 2National Institute of Technology


Abstract

Background: In Standard Limb Lead (SLL) ECG for Sinus Rhythm (SR) volunteers, the atrial repolarization (Ta wave) as a possible indicator for atrial related diseases is undermined. The presence of Ta wave in exercise stress ECG have been noted previously. However, manifestation of Ta wave in SR is limited using SLL. Hence, the Ta wave characteristics of stress SLL ECG is normal or exaggerated in response to increased cardiac activity is not yet established. Modified Limb Lead (MLL) system is used in this study, which helps in witnessing the Ta wave in SR heart. Therefore, assist to determine Ta wave characteristics and its study for early disease determination.
Objective: This study delineates the higher Ta wave amplitude observed in Sinus Tachycardia (ST) after exercise stress test compared to the SR using MLL system. Methods: MLL was recorded for eight SR and fifteen ST volunteers (mean age 24 years). P-R AND S-T segment amplitudes were measured and analyzed for SR and ST. Results: Ta wave related impact on PR and ST segment have been noted and found 41.60 % increase in P-RST to P-RSR and 49.60% in S-TST to S-TSR. Moreover, Ta wave peak can be predicted with the change in morphology and amplitude of PR and ST segment. Conclusion: Determination of Ta wave peak may help in delineation of atrial related disease conditions. Detailed study on S-T segment depression and elevation help decrease in the false negative detection of myocardial infarction. Keywords: Atrial repolarization, Modified limb lead, Sinus rhythm, Sinus tachycardia, Standard limb lead, Myocardial infarction.