gms | German Medical Science

Background: Electrocardiography, known more than 100 years, still remains the basic method for routine check in cardiology due to its low cost, absolute non-invasiveness and easiness to proceed. However, sensitivity and specificity of ECG are rather low compare to other, newest diagnostic methods. Modern computer technologies gave the possibilities to increase significantly value of electrocardiographic examination, to make ECG examinations useful even in the cases when routine analysis ECG is not informative, open new fields for ECG applications. First of all new approaches of computerized ECG analysis are focused on ventricular repolarisation (ST-T interval), as the most sensitive to any alterations part of cardiocycle. Aim of this study was to investigate intraindividual variability of T- wave shape during normal daily activity.

Methods: 8 healthy volunteers underwent numerous repeatable examinations in the different life situations (in the morning immediately after wake up , during the normal working activity, under different kinds of stress etc) . Electrocardiogram was registered with the help of special device , allowing input the1-st standard ECG lead from the hands. ECG . Duration of registration was 30 sec. All ECG were stored on hard disk for further analysis Than T-wave shape was analyzed with the help of original software package „Fazograph“.

Results: Systematic changes of T-wave symmetry were revealed. In all volunteers T-waves were the most asymmetric in the morning , became more symmetric during normal daily activity. The highest symmetry of T-wave was registered under conditions of emotional stress ( for instant public speech).

Conclusion: The shape of T-wave seems to be sensitive to level of stress and fatigue.