The electrical<unk>  of the heart is the net direction in which the wave of depolarization travels. It is measured using an electrocardiogram (ECG). Normally, this begins at the sinoatrial node (SA node); from here the wave of depolarisation travels down to the apex of the heart. The hexaxial reference system can be used to visualise the directions in which the depolarisation wave may travel. On a hexaxial diagram (see figure 1): * If the electrical<unk>  falls between the values of -30° to +90° this is considered normal. * If the electrical<unk>  is between -30° to -90° this is considered left<unk><unk> . * If the electrical<unk>  is between +90° to +180° this is considered<unk>  <unk> .<unk>  is an ECG finding that arises either as an anatomically normal variant or an indicator of underlying pathology.
Right axis deviation
Pulsus alternans
Dichotic pitch
Heart click
Shifting dullness
Apex beat
Precordial thump
Third heart sound