Ventricular escape beat reaching the ventricles (normally initiated by the heart's sinoatrial node (SA node), transmitted to the atrioventricular node (AV node), and then further transmitted to the ventricles) falls below the base rate determined by the rate of Phase 4 spontaneous depolarisation of ventricular pacemaker cells. An escape beat usually occurs 2–3 seconds after an electrical impulse has failed to reach the ventricles. This phenomenon can be caused by the sinoatrial node (SA node) failing to initiate a beat, by a failure of the conductivity from the SA node to the atrioventricular node (AV node), or by atrioventricular block (especially third degree
Node (Well of Echoes) or node-drainers that drain the node of the field and render anything that draws power from it useless. Mancers who cannot draw from a distat node's field must rely on charged crystals, while clankers, constructs and any other devices of the Art will not work. There are also rare places called anti-nodes, where the Art does not work or is at least greatly reduced. Node (Well of Echoes) Nodes are fictional, naturally occurring phenomena in Ian Irvine’s "The Three Worlds Cycle" of novels. They often occur in places where there is a significant landmark, such as on a hill or