CV - Quiz 3 Cardiac Cycle, Control of Cardiac Output

Question 1

1. The cardiac cycle has how many phases?

Answer 1

Seven phases (Klabunde, pg 62)

Question 2

2. What phases of the cardiac cycle are part of ventricular systole?

Answer 2

Phase 2 - Isovolumetric contraction
Phase 3 - Rapid Ejection
Phase 4 - Reduced Ejection
(Klabunde, pg 64-65)

Question 3

3. What phases of the cardiac cycle are part of ventricular diastole?

Answer 3

Phase 5 - Isovolumetric relaxation
Phase 6 - Rapid Filling
Phase 7 - Dastasis
Phase 1 - Atrial Systole
(Klabunde, pg 65-66)

Question 4

4. During what phase of the cardiac cycle does most of ventricular filling occur?

Answer 4

Phase 6 - Rapid filling (Klabunde, pg 66)

Question 5

5. Does opening or closing of healthy heart valves create heart sounds?

Answer 5

Closing a valve indicates a healthy heart sound (Klabunde, pg 66)

Question 6

6. The incisura or dicrotic notch of the aortic pressure tracing marks the beginning of what?

Answer 6

Diastole (Klabunde, pg 65)

Question 7

7. What valve closes at the dicrotic notch?

Answer 7

Aortic and Pulmonic valves (Klabunde, pg 65)

Question 8

8. During what phases of the cardiac cycle are the mitral and aortic valves both closed?

Answer 8

Phase 5 - Isovolumetric relaxation (Klabunde, pg 65)

Question 9

9. Name the various waves of the CVP.

Answer 9

a wave - atrial contraction
c wave - ventricles contract
v wave - slow atrial filling, A-V valves closed
(Guyton & Hall p 106)

Question 10

10. The first heart sound signifies closure of which heart valves?

Answer 10

A-V valves - Mitral and Tricuspid valves (Klabunde, pg 64)

Question 11

11. The second heart sound signifies closure of which heart valves?

Answer 11

Aortic and Pulmonic Valves (Klabunde, pg 65)

Question 12

12. During which phase of the cardiac cycle is the majority of blood ejected from the left ventricle?

Answer 12

Phase 3 ~ 70% blood ejected

Question 13

13. During which phase of the cardiac cycle does most of the filling of the left ventricle occur?

Answer 13

Phase 6 ~ 70% filling occurs

Question 14

14. How much does atrial “kick” contribute to ventricular filling? Does it vary with different rhythms?

Answer 14

~ 10% contributed to ventricular filling

With Increased HR, Atrial Kick can account for upto 40% of filling. With A-Fib, atrial filling does not contribute to ventricular filling (Klabunde, pg 63)

Question 15

1. What are the 4 major determinants of cardiac output?

Answer 15

CO = HR x SV
SV = EDV - ESV
EF = SV / EDV

Question 16

2. Under normal circumstances stroke volume can be increased by increasing or decreasing end-diastolic volume (no change in ESV)?

Answer 16

Increasing

Question 17

3. Under normal circumstances stroke volume can be increased by increasing or decreasing end-systolic volume (no change in EDV)?

Answer 17

Decreasing

Question 18

4. What is the Bowditch Effect? What is the Treppe Effect? What is the Staircase Phenomenon?

Answer 18

Different names for the same thing.

Increased HR can cause + Inotropy (Klabunde, pg 82)

Question 19

5. Why do extremely high heart rates result in a decrease in cardiac output?

Answer 19

Increased HR leads to decreased SV due to reduced diastolic filling time which will decrease EDV (Klabunde, pg 82)

Question 20

6. As preload increases (within normal limits) cardiac output increases. What is the name for this phenomenon?

Answer 20

Frank-Starling Mechanism (causes an upward shift on the curve)

Question 21

7. As preload decreases cardiac output decreases. What is the name for this phenomenon?

Answer 21

Frank-Starling Mechanism (causes a downward shift on the curve)

Question 22

8. What physiologic relationship keeps cardiac output of the ventricle matched with venous return?

Answer 22

Frank-Starling Relationship - increased stretch of myocardium yields a greater contraction which leads to increased CO

Question 23

9. What physiologic relationship keeps the cardiac output of the right and left ventricles matched?

Answer 23

Frank-Starling Mechanism (Klabunde, pg 74)

Question 24

10. What are some of the things that affect ventricular preload?

Answer 24

Venous blood pressure
Heart Rate (filling time)
Ventricular compliance
Atrial Contraction
Inflow or Outflow Resistance
Ventricular Systolic Failure

Question 25

11. What is the Frank-Starling Relationship?

Answer 25

Increased venous return, ventricular filling, and preload leads to increased myocardial stretch which yields an increased SV

Question 26

12. What parameter is represented on the “y” axis (vertical axis) of the Starling Curve?

Answer 26

Stroke Volume

Question 27

13. What parameter is represented on the “x” axis (horizontal axis) of the Starling Curve?

Answer 27

LVEDP

Question 28

14. What factors can cause an increased after load?

Answer 28

• High aortic pressure
• Increased SVR
• Aortic Valve Stenosis
• Ventricular Dilation

Question 29

15. Increases in afterload cause cardiac output to increase or decrease?

Answer 29

Decrease

Question 30

16. Wall stress can be used to help understand what determinant of cardiac output?

Answer 30

Afterload???

Question 31

17. Define contractility.

Answer 31

Inherent capacity of myocardium to contract independently of changes in preload or afterload

Question 32

18. What is another name for contractility?

Answer 32

Inotropy

Question 33

What is the Anrep Effect?

Answer 33

An abrupt increase in Afterload will lead to a modest increase in Inotropy

Question 34

What are the 3 biggest factors affecting inotropy?

Answer 34

Sympathetic activation
Catecholemines
Systolic failure (neg effect)

Question 35

Who’s your Valentine?

Answer 35

Insert Name Here