Taylor- Cardiac Output

Question 1

3 ways the body can alter stroke volume

Answer 1

contractility, aortic pressure, venous pressure

Question 2

cardiac output of the heart=

Answer 2

stroke volume x HR

Question 3

cardiac output of vasculature=

Answer 3

MAP/SVR

Question 4

increasing volume increases _____ of contraction

Answer 4

strength (Starling’s law)

Question 5

A, B, C, D

Answer 5

ejection loop
A: diastolic filling
B: isovolumetric contraction
C: ejection
D: isovolumetric relaxation

Question 6

ejection fraction=

Answer 6

SV/LVEDV

Question 7

normal ejection fraction

Answer 7

above 0.50

Question 8

real ejection loop has rounded top since bp changes during ejection

Answer 8

auxotonic beat

Question 9

increased contractility does what to stroke volume; what about LVESV

Answer 9

increases it (can eject more blood out); LVESV is lower

Question 10

decreasing contractility does what to SV and LVESV

Answer 10

decreases SV; LVESV is higher (less blood ejected)

Question 11

raising aortic pressure does what to emptying of the heart (increases afterload)

Answer 11

opposes emptying of the heart

Question 12

increasing aortic pressure does what to SV and LVESV

Answer 12

SV decreases; LVESV higher (can’t empty contents of heart well)

Question 13

lowering aortic pressure (reducing afterload) allows ventricle to do what

Answer 13

empty more completely

Question 14

decreasing aortic pressure does what to SV and LVESV

Answer 14

increases SV; LVESV lower

Question 15

increasing venous pressure does what to SV and LVEDV

Answer 15

increases SV; LVEDV is higher (increased preload)

Question 16

decreasing venous pressure does what to SV and LVEDV

Answer 16

SV lower; LVEDV lower

Question 17

how much arterial pressure the heart works against during systole

Answer 17

afterload

Question 18

how hard the heart contracts during systole

Answer 18

contractility

Question 19

how much blood fills the heart from venous side during diastole

Answer 19

preload

Question 20

fundamental determinant of stroke volume and cardiac output; determines preload

Answer 20

central venous pressure

Question 21

what happens to LVEDV and SV when ventricular hypertrophy is present

Answer 21

LVEDV decreased due to reduced diastolic compliance; SV decreases

Question 22

what happens at high HR’s to CO and why

Answer 22

decreases; less filling time b/t beats

Question 23

why does CO increase with increasing HR during EXERCISE

Answer 23

sympathetics speed up both contraction and relaxation (more diastolic filling time)

Question 24

what happens if heart is
NOT pumping

Answer 24

no flow and bp constant at 7mmHg

Question 25

heart and circulation relationship

Answer 25

interdependent

Question 26

heart SV increased, venous pressure would ____ in response

Answer 26

decrease; heart pulling more blood out from venous side reducing venous pressure

Question 27

increase volume and pressure provides more ____ to the heart and the more you get out

Answer 27

load

Question 28

meaning of this

Answer 28

only 1 cardiac output and venous pressure that can satisfy the system (it’s self-correcting)

Question 29

3 things that can alter cardiac output

Answer 29

contractility
venous tone or blood volume
arteriolar tone (SVR)

Question 30

increasing contractility will do what to CO and venous pressure

Answer 30

CO will increase; venous pressure will fall

Question 31

decreasing contractility does what to CO and venous pressure

Answer 31

CO decreases; venous pressure increases

Question 32

one of the reasons venous pressure rises in heart failure

Answer 32

contractility decreased and CO decreased

Question 33

increasing blood volume (hypervolemia) will do what to CO

Answer 33

CO increases

Question 34

decreased blood volume will do what to CO

Answer 34

CO decreases

Question 35

best guide for adjusting blood volume in patients

Answer 35

venous pressure

Question 36

venous constriction does what to CO

Answer 36

CO increases

Question 37

venous dilation does what to CO

Answer 37

CO decreases

Question 38

if the heart is stopped, increasing or decreasing resistance has what effect on CO

Answer 38

no effect

Question 39

when the heart is pumping, increasing resistance has what effect on arterial and venous pressure

Answer 39

raise arterial (upstream) and lower venous (downstream)

Question 40

decreasing arteriolar tone (SVR) does what to aortic pressure and SV and CO

Answer 40

aortic pressure decreases
SV increases
CO increases

Question 41

increasing arteriolar tone (SVR) will have what effect on CO

Answer 41

CO decreases

Question 42

exercise’s effect on CO

Answer 42

increased CO

Question 43

2 main things that happen during exercise that increase CO

Answer 43

high sympathetic drive (increase contractility and venoconstriction)
arteriolar dilation in active muscle
ACTIVE HYPEREMIA

Question 44

reduced contractility of heart increases_____ and lowers ______ in heart failure

Answer 44

venous pressure
CO

Question 45

during heart failure w/ poor perfusion, body will retain fluid and _____ blood volume (restoring CO but further raising venous pressure); what is this called

Answer 45

increases; compensated heart failure

Question 46

main cause of elevated venous pressure in heart failure

Answer 46

fluid retention

Question 47

contractility of heart continues to degrade and can’t restore CO; venous pressure rises until edema occurs

Answer 47

congestive heart failure