Physiology CVS Flashcards
PASS CVS PHYSIOLOGY EXAM! (124 cards)
1
Q
resistance vessels
A
Arterioles
2
Q
capacitance vessels
A
Veins Venules
3
Q
slow response action potential occurs in the __
A
AV node, SA node
4
Q
the cardiac action potential that occurs in the specialized conducting fibers (Purkinje)
A
Fast response
5
Q
specialized tissue that conducts the cardiac impulse from atria to ventricles
A
AV node
6
Q
important determinants of propagation velocity along myocardial fibers
A
AP amplitude and steepness of the upstroke
7
Q
ECG - atrial depolarization (Phase 0)
A
P wave
8
Q
ECG - AV conduction
A
PR interval
9
Q
ECG - Ventricular repolarization
A
T wave
10
Q
slowest velocity
greatest cross-sectional area
A
Capillaries
11
Q
cardiac output X total peripheral resistance
A
Blood pressure
12
Q
Stroke volume X Heart Rate
A
Cardiac output
13
Q
in baroreceptor reflex
increase in BP –> ___
A
decrease HR
14
Q
in endothelium-mediated regulation
nitric oxide would ___ (dilate/constrict)
A
dilate
15
Q
volume of blood ejected with each heart beat, directly realted to myocardial performance
A
Stroke Volume
16
Q
Regulated by activity of cardiac pacemaker
A
Heart rate
17
Q
Site: atria between RA and vena cava
Between LA and PV
A
Bainbridge Reflex
18
Q
Stimuli of arterial baroreceptors
A
Stretch ( high BP)
19
Q
Volume of blood being pumped by heart per unit time
A
Cardiac output
20
Q
Volume of blood returning to heart per unit time
A
Venous return
21
Q
Blood loss –> decrease cardiac output –> ______
A
Decreased blood pressure
22
Q
Effect of high intracellular Na+ on contractile force of the cardiac muscle
A
Increased Ca++,
Increased contractile force
23
Q
Force that stretches relaxed muscle fibers
A
Preload
24
Q
Volume of blood ejected from the left ventricle per heartbeat
A
Stroke volume
25
Sound produced by closure of AV valves
S1
26
Location of Aortic valve
2nd ICS of the R sternal border
27
Valve located between the R atrium & R ventricle
Tricuspid valve
28
Venous pulse wave produced by closure of tricuspid valves
C wave
29
Phase of ventricular systole when semilunar valves open
Isovolumic contraction
30
Phase of cardiac cycle that coincides with peak of R wave
Isovolumic contraction
31
Phase of cardiac cycle characterized by low atrial & ventricular pressures and high ventricular volume
Rapid Filling Phase
32
Mediates transport of Na+ inside cardiac muscle fiber
3 Na+ 1Ca++ transporter
33
Force against which contractile muscle must act
Afterload
34
Ratio of stroke volume to left ventricular end diastolic volume
Ejection fraction
35
Sound produced by oscillation of blood due to atrial contraction
S4
36
Location of tricuspid valve
5th ICS of Left Sternal border
37
Valve located between Right ventricle & pulmonary artery
Pulmonary valve
38
ECG wave produced by ventricular repolarization
T wave
39
Period between closure of semilunar valve and opening of atrio-ventricular valve
Isovolumic Relaxation
40
Phase of cardiac cycle characterized by slow ventricular filling
Diastasis
41
Venous pulse wave caused by atrial contraction
A wave
42
SA node has this type of action potential
(SRAP)
| Slow Response Action Potential
43
Rapid depolarization in cardiac muscle is depicted as phase
Phase 0
44
Amplitude of action potential is greater in this type of action potential
(FRAP)
| Fast Response Action Potential
45
Early repolarization in cardiac muscle is due to
K+ efflux
46
This is the important determinant of duration of plateau of action potential
K+ efflux
47
Two factors that determine the velocity of conduction of action potential
Amplitude
| Rate of depolarization
48
Three ionic contents that mediate slow diastolic depolarization of phase 4
Na+ influx
K+ efflux
Ca++ influx
49
Purkinje fibers have this type of action potential
(FRAP)
| Fast Response Action Potential
50
Phase 2 of action potential is due to
Ca++ influx
51
This phase of action potential is absent in SRAP
Phase 1
52
Predominant type of Ca++ channel present in the heart
L-type
53
Depolarization in slow response action potential is achieved mainly by
Ca++ influx (L channels)
54
Three factors that determine the frequency of pacemaker activity
Maximal negativity of Phase 4
Rate of depolarization
Threshold potential
55
Transmembrane potential during phase 4 is less negative in slow response action potential because of
Inward rectifier K+ channel???
56
Relative refractory period extends beyond phase 3 in slow response action potential. This is known as
Post repolarization refractoriness
57
Two physiologic factors that affect cardiac output
```
Stroke volume (SV)
Heart Rate (HR)
```
CO = SV x HR
58
Effect of increased stroke volume on arterial pulse pressure
Increased PP
59
Hydrostatic pressure in thoracic venae cavae & Right atrium
Central Venous Pressure
60
Resistance vessels of circulatory system
Arterioles
61
Key factor that keeps fluid within capillaries
Plasma colloid oncotic pressure
62
Three conditions that can cause turbulent blood flow
inc Diameter
inc Density
Inc velocity
dec Viscosity
63
Structure that allows flow of venous blood towards the heart
Venous valve
64
Two physiologic factors that affect blood pressure
```
Cardiac Output (CO)
Total Peripheral Resistance (TPR)
BP = CO x TPR
```
65
Effect of increased arterial compliance on arterial pulse pressure
Decreased pulse pressure
66
Capacitance vessels of the circulatory system
Veins & venules
67
Intrinsic contractile behavior of vascular smooth muscles is known as
Vasomotion
68
Major determinant of resistance to blood flow
Decreased vessel Diameter
69
Three conditions that increase lymph flow
Muscle contraction
Increased Capillary pressure
Decreased Plasma oncotic pressure
70
Effect of contraction of vascular smooth muscle on vessel diameter
Decreased diameter
71
The principal controller of heart rate
Autonomic nervous system
72
Blood vessels important for maintenance of blood pressure are the
Arterioles
73
Two mechanisms in the intrinsic regulation of myocardial performance
Frank – Starling Mechanism
| Rate-induced regulation
74
Effect of vagal stimulation on heart rate
Decreased heart rate
75
Hormone that potentiates the cardiotonic effect of catecholamines
Epinephrine/ Norepinephrine
76
An increased in heart rate when blood pressure is decreased
Baroreceptor reflex
77
Change in heart rate associated with respiration
Sinus arrhythmia
78
Contraction of vascular muscle in response to increased transmural pressure
Autoregulator
79
Effect of decreased O2 delivery to tissues on arterioles
Vasodilation
80
location of mitral valve
5th ICS Left MCL (cardiac apex)
81
location of Pulmonic valve
2nd ICS Left sternal border
82
oscillation of blood and cardiac chambers due to atrial contraction
4th heart sound
83
oscillation of blood back and forth between the walls and ventricles initiated by rushing blood from atria
3rd heart sound
84
signifies rise in pressure due to ATRIAL CONTRACTION
A wave
85
due to CLOSURE OF TRICUSPID VALVE in early ventricular systole
C wave
86
rise in pressure associated with ATRIAL FILLING
V wave
87
greater atrial filling --> _____ V waves (increase/decrease)
increase
88
flow that requires greater pressure
| responsible for Korotkoff sounds and cardiac murmers
turbulent flow
89
organs with parallel circuits
brain, kidney, GI, skin, coronary circulation
90
decreased arterial compliance --> ___ LV workload
greater
91
decreased arterial compliance --> ___ pulse pressure
increased
92
increased peripheral resistance --> ___ BP
increased
93
prevent blood in vein from falling toward toward feet --> permit flow toward heart
Venous valves
94
forces fluid to go out of capillaries
capillary hydrostatic pressure
95
closure of arterioles/ arteriolar resistance --> ____ capillary hydrostatic pressure
DECREASE capillary hydrostatic pressure
96
increase arterial and venous pressure --> ____ capillary hydrostatic pressure
INCREASE capillary hydrostatic pressure
97
increase coronary blood flow
| + chronotropy, + inotropy --> ____ blood flow
DECREASE blood flow
98
increase HR --> less time for diastole --> ___ blood flow
DECREASE blood flow
99
increase metabolic activity --> ____ diameter --> ____ blood flow
INCREASE diameter , INCREASE blood flow
100
develops due to slow and gradual occlusion of coronary artery
collateral circulation
101
occlusion of blood flow to a tissue/organ then increase in blood flow
reactive hyperemia
102
decrease oxygen in the heart --> stimulates ____
vasodilator metabolite
103
in cerebral circulation
| increase PaC02 --> dilate --> ___ blood flow
INCREASE blood flow
104
in cerebral circulation
| decrease PaC02 --> ___ (constrict/dilate) --> ___ blood flow
CONSTRICT, DECREASE blood flow
105
cerebral circulation:
| increase Adenosine ---> ___ (constrict/dilate)
dilate
106
cerebral circulation:
| increase K+ ---> ___ (constrict/dilate)
dilate
107
cerebral circulation
| BP less than 60 mmHg ---> _____
decrease cerebral blood flow
108
cerebral circulation
| BP greater than 160 mmHg -- leads to __
cerebral edema
109
fetal source of oxygen and nutrients
placenta
110
fetal hemoglobin
greater affinity for oxygen
111
half of blood flow from placenta passes through the liver, the remainder bypasses liver and reaches IVC through ____
ductus venosus
112
fetal circulation:
| blood from umbilical vein is shunted from IVC to LA through ____
foramen ovale
113
fetal circulation
| blood passes from pulmonary artery through ____ to aorta
ductus arteriosus
114
in fetal circulation, why does blood flow from pulmonary artery to aorta?
pulmonary vascular resistance is HIGH
| diameter of ductus arteriosus is as large as descending aorta
115
occlusion of blood flow in umbilical vessels leads to
closure of ductus venosus
116
at birth, reversal of pressure gradient across atria leads to
closure of valve foramen ovale
117
closure of this structure is inititated by increase P02 of arterial blood passing through it
Ductus arteriosus
118
Normal axis
-30 to +110 degress
118
greater amplitude of action potential leads to
faster conduction
119
Right axis deviation
+110 to -180 degrees
120
Left axis deviation
-39to -90 degrees
121
Small increase in atrial and ventricular pressure and ventricular volume
Occurs soon after P wave
Atrial systole
122
Indicated by gradual rise in atrial and ventricular pressures and ventricular volume
Slow filling
123
Dec intravascular pressure -->
Dec diameter -- inc resistance
