…circumstances) the P wave vector is directed downwards and to the left in the frontal plane and this yields a positive P wave in lead…

…cardiac cycle as depolarization and repolarization progress [3]. The mean electrical axis is typically calculated for ventricular activation in the frontal plane using the hexaxial…

…to right inferior. In other words, the following order: aVL, I, −aVR (i.e., lead aVR with reversed polarity), II, aVF, and III. Note that…