Heart Electrical Conduction and Function

Dr. Mike explains the heart's electrical conduction system, starting with the sinoatrial (SA) node, which initiates the heartbeat. The signal travels through the atria, causing them to contract, and is then delayed at the atrioventricular (AV) node. It continues down the Bundle of His, branching into left and right bundle branches, and finally through Purkinje fibers, leading to ventricular contraction. This process ensures efficient blood flow from the heart to the lungs and body.

What is the primary function of the electrical stimulus in the heart?

• To regulate blood pressure

• To initiate heart contraction

• To control body temperature

• To manage oxygen levels

Which part of the heart is responsible for its spontaneous contraction?

• Specialized myocardial tissue

• The ventricles

• The atria

• The autonomic nervous system

What is the role of the sinoatrial node in the heart?

• It filters blood

• It sets the rhythm of the heart

• It pumps blood to the lungs

• It stores calcium

How does the autonomic nervous system affect the heart?

• It stops the heart from beating

• It decreases oxygen levels

• It changes the heart's rhythm

• It increases blood flow

What is the function of the atrioventricular node?

• To delay the electrical signal

• To produce red blood cells

• To store electrical energy

• To pump blood to the body

What happens during the pause at the AV node?

• Calcium is released

• The heart stops beating

• Blood is pumped to the lungs

• The electrical signal is delayed

What is the bundle of His responsible for?

• Storing calcium

• Regulating heart rate

• Pumping blood to the atria

• Carrying the electrical signal to the ventricles

Where do the left and right bundle branches carry the electrical signal?

• To the atria

• To the ventricles

• To the brain

• To the lungs

What is the role of Purkinje fibers in the heart?

• To initiate the heart's rhythm

• To conduct electrical signals to the ventricles

• To store blood

• To regulate blood pressure

What is the sequence of electrical conduction in the heart?

• Purkinje fibers, bundle of His, SA node

• SA node, AV node, bundle of His, Purkinje fibers

• AV node, SA node, Purkinje fibers

• Bundle of His, AV node, SA node