A Software Based Approach for Detection of QRS Vector of ECG Signal

A software based approach for determination of the frontal plane QRS vector is described in this paper. For this purpose, a module is developed for determination of R-R interval of each ECG wave of six limb leads (Leads I, II, III, AVR, AVL and AVF) by using square derivative curve technique. Baseline or isoelectric level of every ECG signal is also determined for accurate computation of net QRS deflection (NQD) at all the six above-mentioned leads. Depending on the rules of cardiac axis determination by searching the minimum NQD, an algorithm is developed for computation of the angle, amplitude and direction of the frontal plane QRS vector for both normal and diseased subjects to find out the clinical significance of this vector in disease identification. In the present work, the PTB diagnostic ECG database is used for computation of the QRS vector and interesting result is achieved.