Cardio 3 Flashcards Preview

PHSI 208 > Cardio 3 > Flashcards

Flashcards in Cardio 3 Deck (31):
1

tachycardia

fast >70/72 bpm

2

bradycardia

slow <70/72 bpm

3

What is the heart rate?

P to P or R to R

4

arrhythmia

abnormal rhythm; can appear as longated segments or intervals, altered, missing or additional waves.

5

premature ventricular contractions

-purkinje fibres kick in as pacemaker due to insufficient oxygen to myocardium; perceived as skipped beat or palpitation

6

long QT syndrome

-inherited
-delayed repolarization of ventricles

7

cardiac cycle

one complete contraction and relaxation

8

diastole

when cardiac muscle relaxes

9

systole

when cardiac muscle contracts

10

5 phases of a single cardiac cycle

-The heart at rest: atrial and ventricular diastole (late diastole)
-completion of ventricular filling (atrial systole)
-Early ventricular contraction (isovolumetric ventricular contraction)
-The heart pumps (ventricular ejection)
-Ventricular relaxation (isovolumetric ventricular relaxation, early
diastole)

11

late diastole

both sets of chambers are relaxed and ventricles fill passively

12

atrial systole

atrial contraction forces a small amount of additional blood into ventricles

13

isovolumetric ventricular contraction

first phase of ventricular contraction pushes AV value closed, but does not create enough pressure to open semilunar valves - LUB

14

ventricular ejection

as ventricular pressure rises and exceeds pressure in arteries, the semilunar valves open and blood is ejected

15

isovolumetric ventricular relaxation

-as ventricles relax; pressure in ventricle falls, blood falls back into cusps of semilunar valves and snaps them close

16

EDV

end diastolic volume; maximal amount of blood in the ventricles after filling; ~ 135mL

17

ESV

the volume of blood left over after contraction; ~65mL

18

A-A' segment of pressure volume loop

starts at ESV
-(late diastole) pressure in ventricle is lower than atria and the AV valve opens causing the ventricle to passively fill with blood

19

A'-B segment of pressure volume loop

- (atrial systole) atria contracts forcing more blood into the ventricle slightly increasing volume and pressure
-EDV

20

B-C segment of pressure volume loop

(isovolumetric contraction) the ventricle begins contracting closing AV valve, continued contraction causes a large increase in pressure within the ventricle

21

C-D segment of pressure volume loop

(ventricular ejection) Once pressure in ventricle rises above ~80mm Hg, it exceeds the aorta and the aortic valve opens causing a rapid ejection of blood

22

D-A segment

isovolumetric relaxation; pressure in aorta begins to exceed ventricle causing semi-lunar valve to close, ventricle continues to relax

23

D - Wiggers Diagram

ventricle relaxes, pressure in atria begins to exceed ventricle -AV valve opens and you get the passive filling of the ventricle
-Atria then contracts increasing the volume and pressure slightly

24

C - wiggers diagram

ventricle beings to contract, increasing pressure within ventricle causing the AV valves to snap shut (LUB)

25

E - wiggers diagram

EDV

26

A - wiggers diagram

ventricle contracts until it exceeds pressure in aorta

27

E to F - wiggers diagram

aortic valve opens and yogurt rapid ejection of blood

28

B - wiggers diagram

pressure in aorta starts to exceed ventricle causing semilunar valve to shut
-DUB

29

SV

stroke volume; amount of blood ejected during contraction; ~70mL

30

SV=

EDV-ESV

31

total blood flow (cardiac output) =

heart rate x stroke volume in L/min