Cardiac Cycle

Question 1

1st step in cardiac cycle:
atrial systole

analagous part on ECG

Answer 1

occurs after P wave (atrial contraction)

Question 2

1st step in cardiac cycle:
atrial systole

part on venous pulse curve

Answer 2

incr in atrial pressure (venous pressure) by atrial systole = A WAVE

Question 3

1st step in cardiac cycle:
atrial systole

auscultation

Answer 3

atrial systole –> ventricular filling –> 4TH HEART SOUND (not audible in normal)

Question 4

2nd step in cardiac cycle:
isovolumetric ventricular contraction

analagous part on ECG

Answer 4

begins during QRS complex (ventricular activation)

Question 5

2nd step in cardiac cycle:
isovolumetric ventricular contraction

part on venous pulse curve

Answer 5

rapid rise in ventricular pressure due to ventricular contraction and no blood leaving ventricle (aortic valve is closed)

Question 6

2nd step in cardiac cycle:
isovolumetric ventricular contraction

auscultation

Answer 6

when ventricular pressure > atrial pressure, AV valve close

(first heart sound)

can be split b/c mitral valve closes before tricuspid valve

Question 7

3rd step in cardiac cycle:
rapid ventricular ejection

what reaches max value?

Answer 7

ventricular pressure

Question 8

3rd step in cardiac cycle:
rapid ventricular ejection

part on venous pulse curve

Answer 8

C wave because of bulging of tricuspid valve into RA during RV contraction

when ventricular pressure > aortic pressure, aortic valve opens –> rapid ejection of blood due to downward P gradient

Question 9

3rd step in cardiac cycle:
rapid ventricular ejection

what happens after RV ejects blood

Answer 9

most of stroke volume ejected

atrial filling begins

Question 10

3rd step in cardiac cycle:
rapid ventricular ejection

part on ecg

Answer 10

onset of T wave (repol of ventricles)

end of both ventricular contraction and rapid ventricular ejection

Question 11

4th step in cardiac cycle:
reduced ventricular ejection

what happens

Answer 11

RV continues to eject blood but SLOWER

atrial filling continues

Question 12

4th step in cardiac cycle:
reduced ventricular ejection

what happens to ventricular and aortic pressure

Answer 12

ventricular pressure DECREASES

aortic pressure also DECREASES because large arteries empty into smaller arteries

Question 13

4th step in cardiac cycle:
reduced ventricular ejection

part on venous pulse curve

Answer 13

V wave because blood flow into RA (rising phase of wave) and then from RA into RV (falling part)

Question 14

5th step in cardiac cycle:
isovolumetric venticular relaxation

part on ECG

Answer 14

end of T wave (repol of ventricles complete)

Question 15

5th step in cardiac cycle:
isovolumetric venticular relaxation

auscultation

Answer 15

aortic valve closes –> then pulmonic valve closes
(both are semilunar valves) –> 2nd heart sound

Inspiration can delay closing pulmonic (splitting of S2)

Question 16

5th step in cardiac cycle:
isovolumetric venticular relaxation

what valve is still closed during this phase

Answer 16

AV valves

Question 17

5th step in cardiac cycle:
isovolumetric venticular relaxation

what happens to ventricular pressure

Answer 17

decr rapidly because ventricle now relaxed

Question 18

5th step in cardiac cycle:
isovolumetric venticular relaxation

what happens to ventricular VOLUME

Answer 18

constant because all valves are closed

Question 19

5th step in cardiac cycle:
isovolumetric venticular relaxation

what unique happens with the aortic pressure tracing?

Answer 19

“blip” rise due to dicrotic notch (INCISURA)

Question 20

6th step in cardiac cycle:
Rapid ventricular filling

what happens

Answer 20

ventricular pressure < atrial pressure –> mitral valve opens to fill LV

Question 21

6th step in cardiac cycle:
Rapid ventricular filling

what happens to aortic pressure

Answer 21

keeps decreasing because blood continue to run off into smaller arteries

Question 22

6th step in cardiac cycle:
Rapid ventricular filling

auscultation

Answer 22

rapid flow of blood from atria into ventricles –> S3 (normal in children, pathologic in adults)

Question 23

7th step in cardiac cycle:
Reduced ventricular filling (diastasis)

is the ____ phase of the cardiac cycle

Answer 23

longest

Question 24

7th step in cardiac cycle:
Reduced ventricular filling (diastasis)

what happens

Answer 24

ventricular filling continues but at slower rate

Question 25

7th step in cardiac cycle:
Reduced ventricular filling (diastasis)

how does heart rate affect time for diastesis/ventricular filling

Answer 25

incr HR, decr time for ventricular filling, decr EDV, decr SV