Cardiac Cycle and Heart Sounds Extra

Question 1

What phase of ventricular AP does the QRS complex occur?

Answer 1

Phase 0–> ventricular depolarization

Question 2

The lowest and highest pressures in the ventricles are 120mmHg and 0mmHg.

When do they occur?

Answer 2

120–> ST segment

0mmHg–>during diatole; at the end of isovolumentric relaxation

Question 3

During ventricular contraction, what happens to the atrial pressure?

Answer 3

Increases as blood returns to the atria.

Question 4

How does aorta pressure compare to the ventricular and atrial pressures?

When does it increase or decrease?

Answer 4

It is generally higher.

• Decreases during atrial systole and isovolumetric ventricular contraction.
• Increases during ventricular ejection.

Question 5

For the LV to open the aortic valve , what must the pressure be?

Answer 5

Pventricle must exceed the diastolic pressure of the aorta (80)

Question 6

What pressures must the LV and RV overcome before they open the semilunar valves?

Answer 6

RV= >15

LV= >80

Question 7

What decreases as the pressure in the ventricle and aorta increase?

Answer 7

Volume in the ventricles because we are ejecting it.

Question 8

What begins diastole?

Answer 8

Closing of the semilunar valves.

Question 9

C wave on the jugular venous pressue?

Answer 9

Isovolumetric ventricular contraction

Question 10

V wave?

Answer 10

Filling of the atria with blood

Question 11

What part of the ECG represent ventricular contraction?

Answer 11

ST segment and QT interval

Question 12

S1

Answer 12

AV valves close: blood hits the closed valves as it tries to get into the ventricle

Question 13

S3

Answer 13

Period of rapid ventricular filling

Question 14

S4

Answer 14

Atrial contraction (atrial kick)

Occurs to the atrial kick: atria is contracting and we are trying to squeeze out the lastblood

Question 15

Ventricular systolic murmur

Answer 15

1. Mitral regurgitation–> blood is trying to go into the atria
2. Stenosis

Question 16

When can a ventricular systolic murmur be heard?

Answer 16

During S1 and S2

Question 17

Ventricular diastolic murmur

Answer 17

1. Aortic regurgitation (blood is going back into the aorta)
2. Stenosis

Question 18

When do we heart a ventricular diastolic murmur?

Answer 18

Whoose after S2

Question 19

QRS complex begins just before what?

Answer 19

Just before we see the increase in ventricular pressure/

Question 20

What is happening during the V wave?

Answer 20

Blood is returning back to the heart, but cannot enter ventricles because the mitral valve is closed.

-Here, the ventricles are contracting