Heart (preload, afterload, contractility, and BP)

Question 1

contractility definition

Answer 1

• the ability of heart myocytes (contractile muscle in the heart) to contract and produce force (stretch)
• Sympathetic stimulation ventricles and myocytes contract to squeeze blood out
• Left ventricle to the aorta to the body

Question 2

Preload definition

Answer 2

• the volume of blood stretching the ventricles (blood that will be ejected)
• initial stretch of cardiac myocytes prior to contractions and related to ventricular filling
• Filling the tank

Question 3

Diastole definition

Answer 3

• filling of the heart

- heart relaxed and blood return to heart through RA

Question 4

Systole definition

what happens when systole is higher than normal?

Answer 4

• blood pumped to the body by ventricles

- higher = more force and push blood into body

Question 5

Where does afterload travel to?

what influences afterload?

Answer 5

• blood to the aorta to the body

- blood vessels constrict or dialte

Question 6

preload:

is the blood oxygenated or deoxygenated?
where does it enter?
what causes low preload?

Answer 6

• deoxygenated
• enter vena cava into wall RA
• no volume (fluid) in body = low preload

Question 7

What causes afterload to increase?

Answer 7

• aortic pressure and system vascular resistance increase through vasoconstriction
• Constrict = more pressure from the heart
• Higher systemic vascular resistance

Question 8

What causes afterload to decrease (what happens to movement)

Answer 8

• when aortic pressure and systemic vascular resistance decrease through vasodilation
• Not move through as efficiently
• Vasodilated
• Volume intro large space

Question 9

Afterload definition

Answer 9

• resistance in arteries the heart must eject blood against
• Pressure that must be exceeded before blood is ejected from the chamber
• Force or load against which heart has to contract to eject blood
• “Load” to which heart must pump against

Question 10

contractility definition

Answer 10

• the ability of heart myocytes (contractile muscle in the heart) to contract and produce force (stretch)
• Sympathetic stimulation ventricles and myocytes contract to squeeze blood out
• Left ventricle to the aorta to the body

Question 11

Diastole definition

Answer 11

• filling of the heart

- heart relaxed and blood return to heart through RA