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Flashcards in Cardiac Physiology Deck (44):
0

Blood flow velocity in the aorta

Fastest

1

Blood flow velocity in the capillaries

Slowest

2

Reynold's number for laminar flow

<2000

3

Reynold's number for turbulent flow

>2000

4

A strain in the structure of a substance produced by pressure, when its layers are laterally shifted in relation to each other

Shear

5

Shear: highest in

Walls of blood vessels

6

Shear: lowest in

Center of blood vessels

7

Shear: consequence

Decreased blood viscosity

8

Compliance of veins vs arteries

24x higher compliance

9

Compliance: effects of aging

Decrease compliance

10

Highest arterial BP

Systolic pressure

11

Lowest arterial BP

Diastolic pressure

12

Systolic pressure - diastolic pressure

Pulse pressure

13

Stroke volume/arterial compliance

Pulse pressure

14

2/3 (diastole) + 1/3 (systole)

Mean arterial pressure

15

Synonym: right atrial pressure

Central venous pressure

16

Estimates left atrial pressure

Pulmonary capillary wedge pressure

17

Hypokalemia

Flat/inverted T waves w/ U waves

18

Hyperkalemia

Low P waves, tall T waves

19

Hypocalcemia

Prolonged QT interval

20

Hypercalcemia

Shortened QT interval

21

STEMI

ST segment elevation

22

NSTEMI

ST segment depression

23

What is the basis for AV nodal delay (0.13 sec)?

Decrease gap junction in that area

24

Which Na channel accounts for the SA node automaticity?

If channels (slow "funny" Na channels)

25

Which is responsible for setting the HR?

Rate of phase 4 depolarization

26

Inhibition of "pacemaking" of latent pacemakers by the SA node

Overdrive suppression

27

AV block that causes fainting in patients due to initially suppressed state of Purkinje Fibers

Stokes-Adams syndrome

28

Condition when latent pacemaker assume pacemaking activity

Ectopic pacemaker

29

Conduction velocity is dependent in which phenomenon?

Size of inward current during upstroke of action potential

30

Produces changes in contractility

Inotropic effect

31

Produces changed in rate of relaxation

Lusitropic effect

32

Produces changes in heart rate

Chronotrophic effect

33

Produces changes in conduction velocity

Dromotrophic effect

34

Inotropes affect:

Stroke volume

35

Dromotropes affect:

AV node/ conduction velocity

36

Beta 1 stumulation of the heart would cause:

Stronger (+ inotrope), Briefer (+ lusitrope), & More Frequent (+ chronotrope) contractions

37

Primary source of energy for stroke work:

Fatty acids

38

Physiologic murmur occur only during systole or diastole?

Systole

39

Most potent vasoconstrictor

Vasopressin

40

Released as a result of blood vessel damage; causes arteriolar vasoconstriction; implicated in migraine

Serotonin

41

Released by damaged endothelium

Endothelin 1

42

Counteracts TXA2

Prostacyclin ( PGI2)

43

Vasodilates upstream blood vessels

Nitric acid