Lecture 6

Question 1

Which valves are between the great veins and atria?

Answer 1

there are none!

Question 2

What causes heart valves to close

Answer 2

pressure differential

papillary muscles do not help close- they prevent bulge

Question 3

pressure in distal chamber exceeds proximal chamber

Answer 3

valves close

Question 4

pressure in proximal chamber exceeds distal chamber

Answer 4

valves open

Question 5

Atrial systole

Answer 5

ventricular filling completely via atrial contraction (20% at rest…the rest is done passively)

Question 6

Ventricular systole (3)

Answer 6

Isovolumetric contraction
Rapid ejection
Reduced ejection

Question 7

ventricular diastole (3)

Answer 7

isovolumetric relaxation
rapid ventricular filling
reduced ventricular filling

Question 8

End of diastole (3)

Answer 8

all chambers relaxed
AV valves open (atrial pressure slightly higher than ventricular)
Pulmonary and aortic valves closed (aoritc and pulmonary pressure higher than ventricular)

Question 9

A wave of venous pressure reflects

Answer 9

Atrial systole

Question 10

EDV

Answer 10

the volume of blood in the ventricle at the end of atrial systole

Question 11

ventricular systole- isovolumetric contraction(4)

Answer 11

inc in ventricular pressure
QRS complex-ventricular depolarization
Rise in pressure -> AV valve closing
AV valves bulge into atria-> atrial pressure wave (c wave)(think Contraction of ventricles)

Question 12

Ventricular Systole- rapid ejection(2)

Answer 12

ventricular pressure inc above diastolic arterial pressure

semilunar valves open- blood flows into arteries

Question 13

Ventricular systole- reduced ejection(3)

Answer 13

almost no blood flow, but ventricle remains contracted
eventually flow briefly reverses-> closure of aortic and pulmonary valves
Abrupt closure of aortic valve causes dichrotic notch

Question 14

end of ventricular systole

Answer 14

build up of blood(from veins) in atria causes atrial v wave

Question 15

SV

Answer 15

volume of blood ejected

SV=EDV-ESV

Question 16

Ejection fraction

Answer 16

proportion of EDV ejected

EF=SV/EDV

Question 17

is diastole or systole longer

Answer 17

at rest diastole (ventricular) is 2x length of systole

Question 18

ventricular diastole- isovolumetric relaxation

Answer 18

closure of outflow valves

Question 19

ventricular diastole- rapid ventricular filling

Answer 19

ventricular pressure falls below atrial pressure, AV valves open and atrial pressure falls rapidly as ventricles fill

Question 20

ventricular diastole- reduced refilling

Answer 20

ventricles relax completely and refilling slows

Question 21

pressure volume loops

Answer 21

can be used to describe changes occurring in disease states that affect either filling or pumping

Question 22

Systolic pressure

Answer 22

peak pressure at point of maximal ejection of blood from ventricle

Question 23

diastolic pressure

Answer 23

pressure when outlet valves are closed

Question 24

Major difference between right and left heart in regards to pressures

Answer 24

right heart= magnitude of systolic pressures. lungs have much lower resistance to flow, so less arterial pressure required

Question 25

1st and 2nd heart sounds mark

Answer 25

the beginning and end of ventricular systole

Question 26

1st sound

Answer 26

closure of AV valves(bi and tricuspid)

Question 27

2nd sound

Answer 27

closure of outlet valves (pulmonic and aortic)

Question 28

3rd heart sound

Answer 28

generally weak and difficult to hear (except horses)

mid diastole-vibrations due to entry of blood to ventricle

Question 29

4th sound

Answer 29

occurs with atrial contraction

similar to 3rd heart sound

Question 30

murmur- gallop rhythm

Answer 30

splitting of the 1st and 2nd heart sounds producing triple instead of double sound

Question 31

Measures of the heart’s performance(3)

Answer 31

SV(=EDV-ESV)
HR
CO (=HRxSV)