Class 6

Question 1

Ventricular dilation will give an increase in what?

Answer 1

Increase in ventricular compliance or LVEDPVR slope

Question 2

How can you examine how ventricular dilation can effect EDV?

Answer 2

Compliance filling curve

Question 3

A normal heart has a steeper slope which means what for the compliance?

Answer 3

Lower compliance

Question 4

Dilated ventricle enhances what?

Answer 4

Venous return

Question 5

Hypertrophic heart has a steeper slope which means what on the LVEDPVR?

Answer 5

Lower complains

Question 6

Increased heart thickness means web for compliance?

Answer 6

Decrease in ventricular compliance

Question 7

Decrease compliance will increase or decrease end diastolic pressure?

Answer 7

Increases EDP

Question 8

Increase in Venus return will (-)ventricular filling in therefore (-) preload

Answer 8

Increase, increase

Question 9

Increase in end diastolic volume will cause an (-) in end diastolic pressure

Answer 9

Increase

Question 10

In a heart lesser the compliance, slower or quicker venous return

Answer 10

Slower

Question 11

A decrease in venous return will do what to EDV?

Answer 11

Decrease

Question 12

Decrease in pre-load or EDV caused by a decrease in compliance will lead to what for the EDP?

Answer 12

An increase in EDP, lesser volume means higher pressure to eject blood

Question 13

Increase in EDP Implies that the heart must do what to counteract the increase in EDP?

Answer 13

Contract more forcefully to eject the blood

Question 14

Increases in venous return will

Answer 14

• increase preload
• stretch the myocardial contractile myocytes
• increase force of contraction
• increase stroke volume - increase cardiac output

Question 15

What ensures the outputs of both the ventricles are matched overtime and prevents shifting of blood between pulmonary and systemic circulation?

Answer 15

Frank starling mechanism

Question 16

Describe frank starling mechanism

Answer 16

To ensure the outputs of both the ventricles are matched and prevent the shifting of blood between pulmonary and systemic circulation

Question 17

Increase in EDV will do what to force of contraction?

Answer 17

Increase ventricular developed force or force of contraction?

Question 18

For any heart at any time an increase in LVDV will always lead to what?

Answer 18

Increase in LVEDP

Question 19

If you increase the LVEDP what happens to stroke volume?

Answer 19

It increases

Question 20

When keeping all cardiac factors constant except increasing the preload, what happens to SV?

Answer 20

Instantaneous increase in stroke volume, resulting in increase in cardiac output but no change in ESV

Question 21

Increase in stroke volume from an increase in EDV by increasing the venous return alone but not changing the ESV implies that

Answer 21

Such an increase in stroke volume is a direct result from an increase in EDV

Question 22

Is the frank starling mechanism the intrinsic property of a heart at a given physiological condition?

Answer 22

Yes

Question 23

Illustrates relationship between changes of the initial length of a myocyte to the contractile force developed by the heart muscle describes what relationship?

Answer 23

Length tension relationship

Question 24

What is the biophysical basis for the starlings law?

Answer 24

Length tension relationship of the ventricle

Question 25

With an increase in preload what happens to active tension?

Answer 25

Increase

Question 26

Increase in active tension will be accompanied by what happening to the velocity of tension development

Answer 26

Increase in the velocity of tension development, or velocity of muscle shortening

Question 27

What can be defined as the ventricular wall tension developed during ventricular ejection?

Answer 27

Afterload

Question 28

The magnitude of the ventricular wall tension developed is directly related to what?

Answer 28

Resistance, impedance, or pressure that the ventricle must be able to overcome before blood can be ejected

Question 29

What is one of the major components of afterload for the left ventricle?

Answer 29

Aortic pressure

Question 30

Defined as the load against which the heart must counteract before blood can be checked it out

Answer 30

Afterload

Question 31

What can estimate ventricular wall stress?

Answer 31

Laplace’s law

Question 32

How do you calculate wall stress?

Answer 32

O is proportional to (pxr)/2h

Question 33

Wall stress calculations in words

Answer 33

Wall stress is proportional to the product of the intraventricular pressure P, and ventricular radius R, divided by wall thickness H

Question 34

Wall stress increases in response to

Answer 34

A higher pressure loud, hypertension

Question 35

Wall stress increases in response to (ventricle)

Answer 35

Increase in the chamber size, increase in preload

Question 36

What will reduce wall stress and therefore reduce afterload?

Answer 36

Increase in ventricular wall thickness, ex. left ventricular hypertrophy

Question 37

Ventricular hyper trophy is used as an adaptive mechanism for what?

Answer 37

- offset an increase in wall stress - Induced by the increase in afterload

Question 38

Increase in afterload does what to the frank starling curve?

Answer 38

Shifts it down and to the right

Question 39

With an increase in after load, the heart has to do what?

Answer 39

The heart has to generate a higher pressure to eject the same volume of blood

Question 40

An increase in afterload will do what to the velocity of fibre shortening?

Answer 40

Decrease the velocity during contraction

Question 41

Decrease in velocity of muscle fibres shortening will result in what to stroke volume?

Answer 41

Decrease

Question 42

Changes in afterload produce secondary changes in what?

Answer 42

Preload

Question 43

When there is an increase in afterload/aortic pressure, the ventricle has to do what to the pressure in order to open the aortic valve?

Answer 43

Generate a higher pressure

Question 44

Higher up the road will do what to ejection velocity?

Answer 44

Decrease ejection velocity, decreases SV and increases ESV

Question 45

Increases in ESV due to the increase in afterload is greater than the increase in EDV such that the SV is increased or decreased?

Answer 45

Decreased