Cardiac Function Curves + Pressure-Volume Loops - Quiz 6

Question 1

What is the cardiac function curve?

Answer 1

Frank Starling Curve

Question 2

How does Contractility affect Cardiac Function Curve?

Answer 2

↑Contractility = Up and Left

↓Contractility = Down and Right

Question 3

How does afterload affect Cardiac Function Curve?

Answer 3

↑Afterload = Down and Right

↓Afterload = Up and Left

Question 4

Why does the venous return curve plateau as RA pressure becomes negative?

Answer 4

At negative RAP, veins collapse as they enter thorax and restricts venous return

Question 5

How do blood volume changes affect Venous Return Curve?

Answer 5

↑TBV =

↑Venous Return

↑RAP

↑MCFP

Question 6

How do venous compliance changes affect Venous Return Curve?

Answer 6

↓Compliance =

↑Venous Return

↑RAP

↑MCFP

Question 7

Mean Circulatory Filling Pressure

Answer 7

Circulatory Pressure when heart is stopped and there is no flow

Arterial Pressure falls & Venous Pressures rise until equal

MCFP = 8 mmHg

Question 8

What factors affect MCFP?

Answer 8

TBV & Compliance

Venous Compliance will have most impact

Question 9

Does CO = Venous Return?

Answer 9

It should according to Frank Starling

Question 10

What is thought to be the mechanism behind Frank Starling Relationship?

Answer 10

Optimization of Myosin & Actin - more Ca⁺ to bind to cardiac muscles

Question 11

Factors that Effect Cardiac Function Curve

Answer 11

Afterload & Contractility

Question 12

Blood Reservoirs

Answer 12

Spleen

Liver

Large Abdominal Veins

Venous Plexus under Skin

Heart & Lungs

Question 13

What is Unstressed Volume?

Answer 13

Amt of blood in the vein before pressure is generated

Question 14

When are different Venous Curves parallel?

Answer 14

Changes in Blood Volume or Venous Compliance

Question 15

How do resistance changes effect Venous Return Curve?

Answer 15

↑SVR = Down and Left

↓SVR = Up and Right

No MCFP Change

Curves Unparallel

Question 16

What is the point of Intercept between the Starling Curve and Venous Return Curve?

Answer 16

Where Cardiac Output = Venous Return

Question 17

What happens to the Starling Curve & Venous Return curve during exercise?

Answer 17

Sympathetic stimulation & Low ↑CO & Venous Return

then

Big ↑CO, Venous Return, MCFP

Question 18

What is the Y-axis on Pressure-Volume Loop

Answer 18

Pressure

Question 19

What is the X-axis on the Pressure Volume Loop

Answer 19

Volume

Question 20

What is time’s role in Pressure Volume Loops?

Answer 20

Time plays no role

Question 21

List 1-4

Answer 21

1: Filling
2: Isovolumic Contraction
3: Ejection
4: Isovolumic Relaxation

Question 22

List 1-4

Answer 22

1: Mitral Valve Open
2: Mitral Valve Close
3: Aortic Valve Open
4: Aortic Valve Close

Question 23

List 1-2

Answer 23

1: End-Diastole
2: End-Systole

Question 24

What is the Red Line?

Answer 24

End-Systolic Pressure-Volume Relationship

(ESPVR)

Question 25

End Systolic Pressure Volume Relationship Changes

Answer 25

Change of Intercept Point = ΔAfterload

Change in Slope = ΔContractility

Question 26

What is this showing?

Answer 26

End-Diastolic Pressure-Volume Relationship

Ventricular Compliance

Red line indicates stiff ventricle & higher filling pressure

Question 27

Whats happening here?

Answer 27

Increased Afterload

Question 28

Whats happening Here?

Answer 28

Increased Contractility

Question 29

Whats happening here?

Answer 29

Increased Preload