Cardiopulm - Cardiovascular Physiology

Front 1

Two primary purposes of the CV system?

Back 1

1) Facilitate exchange of substances and energy between cells and external environment
2) Removal of metabolites

Front 2

By what mechanism does the heart pump the blood?

Back 2

Pressure my nigga

Front 3

Cardiac output must = ?

Back 3

Return

Front 4

3 "pump variables?"

Back 4

1) Cardiac output
2) Stroke volume
3) Frequency

Front 5

Of the 3 pump variables which tends to stay fairly consistent?

Back 5

Cardiac output ~ 5l/min for a 70kg male

Front 6

Location of the SA node?

Back 6

Superior right atrium

Front 7

Location of AV node?

Back 7

Kind of between the right atrium, right ventricle and left ventricle.

Front 8

Out of all the conduction pathways which has the highest and the lowest intrinsic rate?

Back 8

SA node = highest
Purkinje fibers = lowest

Front 9

Intrinsic rate of the SA node?

Back 9

~ 100bpm

Front 10

Intrinsic rate of the AV node?

Back 10

40 - 60 BPM

Front 11

Intrinsic rate of the Purkinje Fibers?

Back 11

30-40 BPM

Front 12

Portion of the nervous system responsible for slowing heart rate?

Back 12

Parasympathetic via the Vagus nerve with release of ACh.

Front 13

Bundle of HIS sends current where?

Back 13

Apex and surface of heart

Front 14

Shortest time of depolarization?

Back 14

AV node = .05 m/sec

Front 15

Longest time of depolarization?

Back 15

Purkinje Fibers = 4.0 m/sec

Front 16

List the sequence of firing of the Atrial muscle, the Purkinje Fibers and the Ventricle

Back 16

1) Atrial muscle < 200ms
2) Purkinje muscle <300ms
3) Ventricular muscle ~ 300ms

Front 17

Which has the larger hyperpolarization between the SA node and the AV node?

Back 17

SA node

Front 18

Depolarization of muscles/fibers faster or slower than nodes?

Back 18

Faster (virtually no slope)

Front 19

Apx depolarization threshold for nodes?

Back 19

-55mV

Front 20

Apx depolarization threshold for muscles/fibers?

Back 20

-80mV

Front 21

Steep depolarization of cardiac muscle is d/t?

Back 21

Na coming into the cell

Front 22

Transient repolarization is driven by?

Back 22

Ca coming in

Front 23

Plateau is driven by?

Back 23

Ca (Coming in less???)

Front 24

Repolarization is driven by?

Back 24

K+ leaving cell

Front 25

Resting potential is driven by?

Back 25

Lean current

Front 26

Primary difference between the AP of the ventricular muscle and the SA node?

Back 26

The depolarization of the SA node (phase 0) is driven by Ca and not Na (as it is in the muscle)

Front 27

Which has the faster funny current, parasymp or symp?

Back 27

Sympathetic

Front 28

Factors that increase SA node firing rate?

Back 28

1) Symp stimulation
2) Muscarinic receptor antagonist
3) B agonists
4) Hyopkalemia
5) Hyperthyroidism

Front 29

Factors that decrease SA node firing rate?

Back 29

1) Parasymp stim
2) Muscarinic receptor agonists
3) B-blockers
4) Hyperkalemia
5) Na and Ca channel blockers

Front 30

Component of cardiac cycle that includes: Ventricular relaxing, ventricular filling and atrial contraction?

Back 30

Diastole

Front 31

Component of cardiac cycle that includes: Ventricular contraction and ventricular ejection?

Back 31

Systole

Front 32

Apx how much time of the cardiac cycle is spent in diastole at a HR of 75?

Back 32

500ms

Front 33

Apx how much time of the cardiac cycle is spent in systole at a HR of 75?

Back 33

300ms

Front 34

Where is a pulmonary catheter typically inserted?

Back 34

Jugular V.

Front 35

2 cardiac output equations?

Back 35

1) CO (L/min) = HR (beats/min) x SV (L/beat)
2) CO (L/min) = (MAP [mmHg] - CVP [mmHg])/ SVR (RU)

Front 36

SVR?

Back 36

System Vascular Resistance = Resistance to blood flow by all systemic vasculature EXCEPT pulmonary vasculature

Front 37

CVP?

Back 37

Central Venous Pressure = Describes the BP in the Thoracic Vena Cava - important b/c it determines the filling of the right ventrical

Front 38

Methods to measure CO in humans?

Back 38

1) EKG / Doppler US
2) Angiography / Radionuclide Angio
3) MRI/CT
4) Thermodilution / dye dilution
5) Fick method

Front 39

Doppler uses US to determine...

Back 39

Direction and Velocity of flow.

Front 40

Tricuspid valve sits where?

Back 40

Between R atrium and ventrical

Front 41

Mitral valve sits where?

Back 41

Between the L atrium and ventrical

Front 42

MUGA scane?

Back 42

Multi-unit Gate Aquisition
- Uses a GAMA scanner
- Measures resting cardiac performance
- Radioactively tagged blood

Front 43

Two purposes served by Echo + Thermodilution

Back 43

1) Measures change in temp in different chambers and vessels
2) Measures flow

Front 44

LVEDV - LVESV = ?

Back 44

Stroke Volume

Front 45

Ejection fraction = ?

Back 45

SV/LVEDV (norm >= 55%)