Heart Cycle and Sounds

Question 1

Name the steps in the Heart Cycle.

Answer 1

1. Late diastole
2. Atrial systole
3. Isovolumic ventricular contraction
4. Ventricular ejection
5. Isovolumic ventricular relaxation

Question 2

Describe the blood flow and muscle action in late diastole.

Answer 2

Both sets of chambers are relaxed and ventrciles fill passively

Question 3

Describe muscle action and blood flow in atrial systole.

Answer 3

Atrial contraction forces a small amount of aditional blood into the ventricles

Question 4

Describe muscle action, pressure and blood flow during isovolumic ventricular contraction.

Answer 4

first phase of ventricular contraction pushes AV valves closed but does not create enough pressure to open semilunr valves

Question 5

Describe pressure and blood flow during ventricular ejection.

Answer 5

As ventricular pressure rises and exceeds pressure in the arteries, the semilunar valves open and blood is ejected

Question 6

Describe muscle action, pressure and blood flow during Isovolumic ventricular relaxation.

Answer 6

As ventricles relax, pressure in the ventricles falls, blood flows back into cups of semilunar valves and snaps them closed

Question 7

Describe electrical flow in the Cardiac Conduciton System in the heart.
5

Answer 7

1. SA node depolarizes
2. Electrical activity goes rapidly to AV node via internodal pathways
3. Depolarization spreads more slowly across atria. Conduction slows through AV node (pause so atria can contract-PR interval)
4. Depolarization moves through ventricular conducting system to the apex of the heart
5. Depoarization wave spreads upward from the apex

Question 8

What is the tension on the cordea tendonae?

Once a cord ruptures what will happen?

If patient starts to deteriortate and you are thinking of cord rupture what vessel would you think is affected?

Answer 8

zero

There will be progressive in valve dysfunction. Increasing tension and pressure

You need to do something about it!

Circumflex

Question 9

When aortic and pulmonic valves are closed what part of the cycle is this? AV are open

When they are open? AV are closed

Answer 9

diastole

systole

Question 10

When is ventricluar pressure high in the cycle?

Answer 10

Ventricular systole

Question 11

When does atrial pressure rise?

Answer 11

Slightly during atrial systole (filling) and the first part of ventricular systole when its pushing the last 20% of the blood into the ventricle.

Question 12

Why does aortic pressure go down in diastole?

Answer 12

because blood is now flowing out of it and into the peripheral arteries decreasing its pressure

Question 13

Whats the dicrotic notch?

Whats valves close as the dicrotic notch is happening?

Answer 13

Blood comes back towards the ventricle causing it to close, which depresses it and then it rises up again. Its the bounce

aortic semilunar vavles

Question 14

What is the peak of the R wave represent on an EKG?

Answer 14

border between ventricular diastole and ventricular systole

Question 15

What is the C wave?

Answer 15

mitral valve was open, now its closing and the leaflets collapse and move up

Question 16

What causes the Lubb, Dubb sounds?

What happens if its hardened?

Answer 16

The valves tensing

Less tension/movement so less sound

Question 17

What are the ACV waves? and what do they correspond to?

Answer 17

A wave is atrial contraction (increase in pressure in the atria) that occurs at the end of diastole

C wave is triscupid bulging-IVC.(increase in pressure in the atria) that occurs during early systole.

V wave is systolic filling of the (increase pressure in the atria) atrium that happens during late systole.

Question 18

Which sound is louder and why: Pulmonic or Aortic?

Answer 18

aortic (loud- more pressure)

pulmonic

Question 19

With inspration there is increased fillings of the atrium, ventricle and increased _______ _______.

Answer 19

ejection fraction