Preserving Cardiac Output in Acute Stress Flashcards Preview

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Flashcards in Preserving Cardiac Output in Acute Stress Deck (13):
1

True/False: In relaxed muscle, myosin head binds to actin

False

In relaxed muscle, Tropomyosin blocks the binding site

2

True/False: In contracting muscle, tropomyosin blocks the binding site

False

Myosin head binds to actin for the power stroke to occur

3

On the Tension-Length curve for cardiomyocytes, what does it mean when the curve is shifted right?

Shifted right -> calcium sensitivity is less because it takes more Ca to generate the same force

4

On the Tension-Length curve for cardiomyocytes, what does it mean when the curve is shifted Left?

Shifted left --> calcium sensitivity is greater because less Ca generates more force

5

Most beta-agonists are (circle one) inotropes/lusitropes

inotropes

- contractility

6

What is the pretentious word for heart rate?

Chronotropy

7

List some Factors that influence EC50(calcium sensitivity) include:

□ pH
□ Temp
□ Sarcomere length
□ Contractile protein phosphorylation
□ Caffeine
↑s in Ca2+ ↑ strength of contraction

8

What is the effect of increasing preload on force of contraction:

the greater the volume of blood entering the heart during diastole (EDV), the greater the volume of blood ejected during systolic contraction (SV) and vice versa

9

Stroke volume is a reflection of ________

end diastolic volume (EDV)

EDV-ESV

10

In the Frank-Starling SV-LVEDP graph, a rightward shift indicates? Leftward?

Rightward: decreased inotropy

Leftward: increased inotropy

(contractility)

11

Via ______ 's law, an increase in preload, _____ SV on the next beat

Starlings, Increases SV

(graph widens)

12

Increased ______ decreases SV on the next beat

afterload

(graph shortens)

13

Increased ______ increases SV on the next AND ______ beats

inotropy, subsequent

(graph widens and gets taller)