Colorful Abstract Adventure Children's Book Cover (1)

THE STORY OF

My Heart

Heart Beat

Definition:
A complete event of contraction
phase (systole) and relaxation phase

(diastole) of heart

InitiatAionnOovfe
Hrveiaerwt Beat:

InitiatAionnOovfe
Hrveiaerwt Beat:

Initiation of Heart
Beat

• Sinoatrial node / SA node generate
electrical impulse

• The impulse spreads across both atria wall

• Causing atria to contract simultaneously
(atria systole)

Initiation of Heart
Beat

•Impulse from atria reach the AV node

•The impulse are delayed for 0.1 second
at AV node before spreading to the walls
of ventricles
**To allow both atria finish contracting
and empty completely before the
ventricles contract

•From AV node, impulse is transmitted to
the bundle of His.

Initiation of Heart
Beat

•From bundle of His, impulse is
transmitted to the right and left bundle
branches

•And then to the Purkinje fibers

•Purkinje fibers spreads the impulse to
heart apex and then spreads to both
ventricles

•Causing both ventricles to contract
simultaneously from the heart apex
upwards (ventricle systole)

Video

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