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Flashcards in The cardiac cycle Deck (16):
1

systolic pressure

The highest pressure in the aorta
round 120mmhg

2

diastolic pressure

The lowest pressure in the aorta
Round 80mmhg

3

End diastolic volume

The highest volume at the end of diastole
highest volume of blood in the ventricles

4

End systolic volume

The highest volume at the end of systole
ventricles filling into aorta

5

Pulse pressure

Systolic pressure - Diastolic pressure
increases as you get older as elastic fibres die

6

stroke volume

EDV-ESV

7

Ejection fraction

SV/EDV
Better representation of the function of the heart
A healthy heart usually ejects about 2/3 of its total stroke volume

8

Atrial systole

Atria contract and push last bit of blood into ventricles

9

Isovolumic ventricle contraction

AV valves close- pressure in ventricles becomes greater than pressure in aorta

10

Ventricle ejection

Semilunar valves open and blood flows into major vessels

11

Isovolumic ventricle relaxation

pressure in major vessels is greater than in ventricles so semilunar valve close

12

Late diastole

AV valves open
Blood flows into ventricles from atria passively

13

What do the different curves in the pressure diagram for the atria represent

A- atria contract and push last bit of blood into ventricles
C- mitral valve closes and bulges back into atrium as it is made of elastic tissue
V- blood coming back from the lungs

14

how long does each cycle last

0.8 s which means average heart rate should be about 70-75 bpm

15

What is the diastolic notch

point at which aortic valve snaps shut
the aorta is an elastic artery so when this happens it releases elastic energy

16

what does a phonogram show and what are murmurs due to?

1st- when AV valves close
2nd- when semilunar valves close
murmurs due to:
-stenosis: narrowing of valves which should be open
-regurgitation