Exam 3 CVS 1-4 Flashcards
1
Q
Atria and ventricles are separated by _______.
A
Atrioventricular Valves
2
Q
left AV valve
A
Mitral Valve
3
Q
Right AV valve
A
Tricuspid valve
4
Q
_______ are positioned between the ventricles and the great arteries
A
Semilunar Valves
5
Q
What are the two semilunar valves?
A
Aortic valve and Pulmonary valve
6
Q
propels blood through the pulmonary circulation
A
right ventricle
7
Q
propels blood through the systemic circulation
A
left ventricle
8
Q
what are the 3 diff types of cardiac cells
A
- myocardial cells
- pacemaker cells
- conduction cells
9
Q
striated muscle specialized for contraction and impulse conduction
A
myocardial cells
10
Q
cells that exhibit automatic rhythmical electrical discharge in the form of APs
A
Pacemaker cells
11
Q
cells that conduct the APs through the heart providing and excitatory system that controls the rhythmical beating
A
conduction cells
12
Q
Fibers remain separate but contract together as a single unit
A
Syncytium
13
Q
What are the two types of cell - cell junctions found within intercalated disks
A
- gap junctions
2. desmosome
14
Q
What is the purpose of gap junctions?
A
allow rapid diffusion of ions
15
Q
what is the purpose of desmosomes?
A
provide mechanical strength
16
Q
Where is the main source of energy for cardiac muscle derived from?
A
oxidative metabolism of fatty acids
17
Q
The normal pacemaker of the heart
A
Sinoatrial node (SA node)
18
Q
where is the SA node located?
A
Right atrium
19
Q
_____ initiates the AP that is conducted throughout the heart
A
SA node
20
Q
T/F. the Sarcoplasmic reticulum is not well developed in cardiac muscle
A
T
21
Q
what are the 2 places where calcium is derived in order to make AP
A
- Extracellular fluid
2. sarcoplasmic reticulum
22
Q
What generates the normal heart rythm?
a. Myocardium
b. sinoatrial node
c. atrioventricular node
d. purkinje fibers
A
B. SA node
23
Q
delays impulse conduction from the atria to the ventricles
A
AV node
24
Q
where is the AV node located?
A
Behind the tricuspid valve in the R atrium
25
Why does the AV node delay the impulse from the atria to the ventricles?
to allow time for the atria to empty their blood into the ventricles before ventricular contraction begins
26
Trace AP through the heart:
1. SA node generates impulse
2. Impulse pulse at AV node
3. AV bundle connects atria to ventricles
4. bundle branches conduct impulses thorough the interventricular septum
5. purkinje fibers depolarize the contractile cells of both ventricles
27
Lead the AV node impulse through the AV bundle into the ventricles
Purkinje fibers
28
______ allows for instantaneous transmission of the cardiac impulse throughout the entire remainder of the ventricular muscle
Purkinje fibers
29
Is the AP in the SA node fast or slow compared with atrial and ventricular cells?
slow
30
What are funny sodium channels? and when are they open?
Pacemaker sodium channels
during slow AP:
closed during AP
begin to open spontaneously once an AP has finished
31
What are fast calcium channels? when are they open?
T-type calcium channels
begin to open near threshold of slow AP
32
what is the ion primarily responsible for the AP in a pacemaker cell?
Calcium
33
During slow AP in SA node, the repolarization occurs after the closing of_____ and opening of _______
Closing: L-type calcium channels
Opening: K channels
34
The myocardium AP (fast AP) is caused by the opening of 2 channels:
1. Fast sodium channels
| 2. L-type calcium channels
35
Which cells have a shorter AP, atrial or ventricular?
Atrial
36
Movement away from the baseline in either a positive or negative direction
waveform
37
a line between waveforms
segment
38
a waveform and a segment
interval
39
several waveforms
complex
40
numbers of heartbeats per min.
HR
41
inc. in HR
Tachycardia
42
Dec. in HR
bradicardia
43
Normal cardiac rhythm where depolarization begins at the SA node
Sinus Rhythm
44
Abnormal heart rhythm
Arrhythmia
45
First ECG deflection
P wave
46
ECG: What is the P wave
Depolarization of atrial muscle
47
ECG: What are the 2 parts of the P wave?
R. atrial depolarization and L atrial depolarization
48
ECG: What segment follows the P wave?
P-R segment
49
ECG: What does the P-R segment correspond to?
AV node conduction
50
ECG: the ______ is the time from initial depolarization of the atria to initial depolarization of the ventricles
P-R interval
51
ECG: How does sympathetic and parasympathetic stimulation affect the P_R interval?
S: inc. conduction velocity
P: dec. conduction velocity
52
ECG: As the impulse activates the His-Purkinje system and ventricular muscle, ________ is generated.
QRS complex
53
ECG: wave that corresponds to early ventricular depolarization
Q
54
ECG: wave that corresponds to ventricular depolarization
R
55
ECG: wave that corresponds to late ventricular depolarization
S
56
ECG: The ____ interval reflects the approximate duration of ventricular systole and the ventricular refractory period.
Q-T
57
ECG: The ___ Segment correlates with the plateau of the ventriular AP
S-T
58
ECG: Represents ventricular repolarization
T wave
59
Which interval in an ECG can be used to calculate HR?
R-R
60
The time between one R wave and the next?
Cycle length
61
a positive and negative charge separated by a small distance
dipole
62
Where are the electrodes for eithoven's Triange placed?
RA, LA, LL
63
ET: What color lead is the RA?
White
64
ET: what color lead is the LA?
Black
65
ET: what color lead is the LL?
Red
66
ET: what color lead is the RL
Green
67
ET: what does lead 1 connect?
RA and LA
68
ET: what does lead 2 connect
RA and LL
69
ET: what does lead 3 connect
LA and LL
70
ET: Why are standard bipolar leads most extensively used in vet med?
Provides info on the frontal plane of the heart
71
ET: What are the 3 augmented unipolar leads
aVR
aVL
aVF
72
ET: Augmented lead that measures the voltage from the RA compared to the sum of the other two leads
aVr
73
ET: Augmented lead that measures the voltage from the LA compared with the sum of the other two leads
aVL
74
ET: Augmented lead that measures the voltage from the LA compared with the sum of the other two leads
aVF
75
What do you use to determine the mean electrical axis(MEA)?
Hexaxial System
76
Represents the direction of the average direction of the entire ventricular myocardium
MEA mean electrical axis
77
Contraction and emptying of the heart
Systole
78
relaxation and filling of the heart
diastole
79
the total volume of blood ejected by the heart per minute
cardiac output (CO)
80
the volume of blood ejected by the ventricles on each beat
Stroke volume
81
Trace the pathway of blood through the heart:
deoxegenated blood> Vena cave> R atrium> R ventricle> Pulmonary arteries> Lungs> Oxygenated> pulmonary veins> L atrium> L ventricle> Aorta> circ.
82
Prevent backflow of blood from the ventricles to the atria during systole
AV Valves
83
T/F Valves of the heart open passively
T
84
When do the AV valves open?
When atrial pressure is greater than ventricular pressure
85
When do the AV valves close?
When ventricular pressure is greater than Atrial pressure
86
The AV valves are attached to the papillary muscles by the ________
Chorda Tendinae
87
T/F the function of the Chorda Tendinae is to help open and close the AV Valves?
F. function to pull the vanes of the valves inward toward the ventricles during systole
88
Prevent back flow of blood from the aorta and pulmonary arteries into the ventricles during diastole
Semilunar valves
89
What is the second heart sound?
The closing of the semilunar valves
90
What causes the semilunar valves to close?
higher pressure in the arteries during systole
91
What does the A wave of the wiggers diagram correspond to?
Atrial contraction
92
What does the C wave of the wiggers diagram correspond to?
ventricles begin to contract
93
What does the V wave of the wiggers diagram correspond to?
End of ventricular contraction
94
the ventricles fill with blood during systole or diastole?
Diastole
95
What happens during the first 1/3 of diastole?
pressure inside atria causes AV valves to open and blood to rush into ventricles
96
What happens during the second 1/3 of diastole?
small amount of blood flows into the ventricles
97
what happens during the last 1/3 of diastole?
atria contract and give aditonal 20% of blood to ventricles
98
the outflow of blood from the ventricles during systole begins with _______
isovolumic contraction
99
what is the ejection fraction?
blood that is ejected during systole (60% of total volume)
100
what are the 2 parts of the ejection fraction?
1. Rapid ejection (70%)
| 2. Slow ejection (30%)
101
what is incidura
short period of backwards flow during the end of systole when the AV valves close
102
What is isovolumic relaxation
when both the AV and semilunar valves are closed following Systole
103
During diastole, normal filling of the ventricles increases the volume of each ventricle
End diastolic volume
104
the volume of blood ejected by the ventricle on each beat
stroke volume
105
the remaining volume in each ventricle
end systolic volume
106
the total volume ejected by the heart per minute
cardiac output
107
What are the 4 stages of the volume pressure diagram of the cardiac cycle?
1. period of filling
2. isovolumetric contraction
3. period of ejection
4. isovolumetric contraction
108
What causes the 1st cardiac sound?
closing of the AV valves
109
What causes the 2nd cardiac sound?
closing of the Semilunar valves
110
What causes the 3rd cardiac sound?
Rush of blood into the ventricles
111
What causes the 4th cardiac sound?
The end of diastole during atrial systole
