Cardiac Impulse


  • Topic Anchor: Cardiac Impulse
    • Process
      • Sinoatrial (SA) node
        • Initiates action potentials and sets rhythm of the heart (pacemaker)
      • Atrioventricular (AV) node
        • Conducts electrical impulses from atria to ventricles (hence, “atrio-ventricular”)
      • Bundle of His
        • Carries electrical impulses from AV node to bundle branches between both ventricles
      • Purkinje fibers 
        • Conductive fibers in ventricular walls
        • Allow for strong, unified contraction of ventricles 
    • Contractions spread to surrounding cardiac muscle via intercalated discs
      • Cell connections with desmosomes and gap junctions
        • Gap junctions allow rapid transfer of electrical impulses