Cardiovascular System Review! Flashcards Preview

Physio #2 > Cardiovascular System Review! > Flashcards

Flashcards in Cardiovascular System Review! Deck (16)
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1
Q

The Ventricles contract after the atria, because of the……

A

slow conduction of the AV node

2
Q

What causes the rapid depolarization of Autorythmic cardiac (nodal) cell AP?

A

Voltage gated Ca++ chapels opeing

3
Q

What causes the threshold graded depolarization in Autorhytmic cardiac (nodal) cell AP?

A

Na+ ions leaking in through funny channel PLUS Ca++ ions moving in through T-channels

4
Q

What causes repolarization in the autorythmic cardiac (nodal) cel AP?

A

Reopening of K+ channels plus closing of Ca++ channels

5
Q

What causes the prolonged plateau phase in myocardial ventricular cell AP?

A

Slow, prolonged opening of voltage gated Ca++ channels PLUS the closure of K+ channels.

6
Q

What causes the rapid depolarization in myocardial ventricular cell AP?

A

Rapid opening of Na+ channels

7
Q

What causes the repolarization of myocardial ventricular cell AP?

A

Opening of K+ channels

8
Q

How do you calculate stroke volume?

A

SV=EDV-ESV

9
Q

MAP = ?

A

MAP = CO x TPR

10
Q

CO = ?

A

CO = Stroke volume x Heart rate

11
Q

Sympathetic acting on _____ receptors in Atria increase the _______ which _______ heart rate.

A
  • Beta1 receptors
  • Increases the funny channel
  • Increases Heart rate
12
Q

Parasympathetics acting on ______ receptors in the atria ________ the funny channel, which ________ the heart rate.

A
  • Muscarinic receptors
  • Decrease the funny channel
  • increases heart rate because it decreases parasympathetics
13
Q

How do you control Stroke volume?

A
  • Preload (EDV)
  • Frank starling mechanism
  • Afterload
  • Contractility
14
Q

What 3 factors affect the stroke volume?

A
  1. Preload (EDV) = the volume of blood in the ventricles just before contraction.
  2. Magnitude of sympathetic input to the ventricles (Increases contractility, but not the same as Frank starling mechanism)
  3. Afterload = the pressure against which the ventricle pumps.
15
Q

Increased adenosine in metabolically controlled organ will cause ______.

A

Vasodilation

16
Q

If arterial pressure decreases?

A

Baroreceptor discharge decreases and so fewer impulses travel up the afferent nerves to the medullary cardiovascular center and this induces:
1. Increased heart rate due to increased symp. and decreased parasymp. to heart.
2. Increased ventricular contraction due to increased Symp. to the ventricular myocardium.
3. Increased Arteriole and Venous constriction due to increased symp. to vasculature.
= Increased CO (increased HR and SV) and increased TPR = Normalization of BP.