Heart Action Flashcards
Equation for cardiac output
stroke volume x heart rate
What does myogenic mean?
The heart can beat without an external stimulus
Where is the sino atrial node?
Right atrium
What does the SAN do?
Initiates a wave of depolarisation that spread across the atria, causing them to contract
What does the atrioventricular node do?
Receives wave of depolarisation from SAN and transmits it down the bundle of His and Purkyne Fibres
What is the Annulus fibrosus?
A region of non conducting tissue which prevents depolarisation spreading straight to the ventricles
Why is there a slight delay before the AVN is stimulated?
To ensure the ventricles contract AFTER the atria
Why do ventricles contract from the apex upwards?
To ensure the maximum volume of blood is pumped out
Where is the AVN located?
In the middle of the heart between the atria and ventricles
