In Wolff-Parkinson-White (WPW) syndrome, an extra electrical pathway
between atrium and ventricle causes an abnormal conduction to the
ventricles. An AP is an aberrant cardiac muscle bundle that connect the
atrium to the ventricle, usually at the atrioventricular (AV) annulus.
Majority of AV accessory pathway are make up by working myocardial
cells: conduction over those AP is mediated by sodium current with an
all or none conduction capacity and non decremental electrical
properties.