blood pathways and electrical pathways of heart

need to know heart arteries

right coronary, left main, left anterior descending, circumflex

Nodes of the heart

SA Node, AV junction, Purkinje fibers

SA node rate

60-100 bpm

av junction

40-60 bpm

purkinje fibers

20-40bpm

Conductivity

ability to revieve and transmit impulses

contractility

ability to react to electrical conduction with organized response

excitability

ability to respond to stimulus

impulse formation process

Polarization, depolarization, repolarization

polarization

Positive charges outside cell are balanced with negative charges inside cell

depolarization

sodium and potassium trade places, with sodium rushing into the cell causing contraction

repolarization

return of electrical charges to their original state

SA node

Pacemaker, sinus node, in upper right atrium, generates an electrical signal for atria to contract

internodal pathways

highway between SA node and AV node

AV node

Gatekeeper, in junctional tissue in right atrium near triscuspid valve, delays signal from SA to bundle branches

bundle of His

transmits impulse from av node to purkinje fibers

bundle branches

from bundle of His impulse is split into left and right bundle branch, which is then sent into purkinje fibers

whole pathway of electrical signal

SA node to internodal pathways to av node, to bundle of his, to bundle branches, to purkinje fibers.