Cardiac Physiology

Question 0

Blood flow velocity in the capillaries

Answer 0

Slowest

Question 1

Blood flow velocity in the aorta

Answer 1

Fastest

Question 2

Reynold’s number for laminar flow

Answer 2

<2000

Question 3

Reynold’s number for turbulent flow

Answer 3

> 2000

Question 4

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

Answer 4

Shear

Question 5

Shear: highest in

Answer 5

Walls of blood vessels

Question 6

Shear: lowest in

Answer 6

Center of blood vessels

Question 7

Shear: consequence

Answer 7

Decreased blood viscosity

Question 8

Compliance of veins vs arteries

Answer 8

24x higher compliance

Question 9

Compliance: effects of aging

Answer 9

Decrease compliance

Question 10

Highest arterial BP

Answer 10

Systolic pressure

Question 11

Lowest arterial BP

Answer 11

Diastolic pressure

Question 12

Systolic pressure - diastolic pressure

Answer 12

Pulse pressure

Question 13

Stroke volume/arterial compliance

Answer 13

Pulse pressure

Question 14

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

Answer 14

Mean arterial pressure

Question 15

Synonym: right atrial pressure

Answer 15

Central venous pressure

Question 16

Estimates left atrial pressure

Answer 16

Pulmonary capillary wedge pressure

Question 17

Hypokalemia

Answer 17

Flat/inverted T waves w/ U waves

Question 18

Hyperkalemia

Answer 18

Low P waves, tall T waves

Question 19

Hypocalcemia

Answer 19

Prolonged QT interval

Question 20

Hypercalcemia

Answer 20

Shortened QT interval

Question 21

STEMI

Answer 21

ST segment elevation

Question 22

NSTEMI

Answer 22

ST segment depression

Question 23

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

Answer 23

Decrease gap junction in that area

Question 24

Which Na channel accounts for the SA node automaticity?

Answer 24

If channels (slow “funny” Na channels)

Question 25

Which is responsible for setting the HR?

Answer 25

Rate of phase 4 depolarization

Question 26

Inhibition of “pacemaking” of latent pacemakers by the SA node

Answer 26

Overdrive suppression

Question 27

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

Answer 27

Stokes-Adams syndrome

Question 28

Condition when latent pacemaker assume pacemaking activity

Answer 28

Ectopic pacemaker

Question 29

Conduction velocity is dependent in which phenomenon?

Answer 29

Size of inward current during upstroke of action potential

Question 30

Produces changes in contractility

Answer 30

Inotropic effect

Question 31

Produces changed in rate of relaxation

Answer 31

Lusitropic effect

Question 32

Produces changes in heart rate

Answer 32

Chronotrophic effect

Question 33

Produces changes in conduction velocity

Answer 33

Dromotrophic effect

Question 34

Inotropes affect:

Answer 34

Stroke volume

Question 35

Dromotropes affect:

Answer 35

AV node/ conduction velocity

Question 36

Beta 1 stumulation of the heart would cause:

Answer 36

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

Question 37

Primary source of energy for stroke work:

Answer 37

Fatty acids

Question 38

Physiologic murmur occur only during systole or diastole?

Answer 38

Systole

Question 39

Most potent vasoconstrictor

Answer 39

Vasopressin

Question 40

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

Answer 40

Serotonin

Question 41

Released by damaged endothelium

Answer 41

Endothelin 1

Question 42

Counteracts TXA2

Answer 42

Prostacyclin ( PGI2)

Question 43

Vasodilates upstream blood vessels

Answer 43

Nitric acid