The cardiovascular system: The heart Flashcards
(216 cards)
1
Q
Where is the heart located?
A
The heart rests on the diaphragm, with 2/3 of it lying to the left of the midline, located within the mediastinuum
2
Q
What does the mediastunum contain?
A
- Heart, ascending aorta, SVC
- Trachea
- Main stem bronchi
- Esophagus
3
Q
Where is the mediastinum located?
A
Between the lungs, from 1st rib to the diaphragm, from the sternum to the vertebral column
4
Q
T/F
The whole heart lies within the mediastinum?
A
True
5
Q
Where is the heart in relation to the thoracic cavity?
A
It is anterior
6
Q
Label 1-4
A
- SVC
- Diaphragm
- Arch of aorta
- Pulmonary trunk
7
Q
Label 1-4
A
- Heart
- Pericardial cavity
- Aorta
- Pulmonary trunk (artery)
8
Q
What affects the size of the mediastinum?
A
- Being supine vs. erect
- Rotation
- Being AP supine vs. PA erect
- Effect of gravity
- Inspiration vs expiration
9
Q
In which position does hte mediastinum appear larger in; supine or erect? Why?
A
Supine; gravity
10
Q
How were both of these images aquired?
A
A: AP supine
B:PA erect
11
Q
How was this image aquired?
A
Supine
12
Q
How do you measure the cardiothoracic ratio?
A
Measure the widest parts of the heart and divide by the size of the widest part of the thorax
13
Q
What should the CT ratio not exceed?
A
Should not exceed by 50%
14
Q
What is indicated if the CT ratio is higher than 50%?
A
Cardiomegly
15
Q
What are the arrows pointing to?
A
A PTX
16
Q
What are these arrows pointing to?
A
Arm and mass
17
Q
What are the layers of the pericardium?
A
- Fibrous
- Serous pericardium
18
Q
What are the layers of the serous pericardium?
A
Parietal and visceral
19
Q
What is the fibrous pericardium? What is its function?
A
-It attaches to the adventitial layers of the aorta, pulmonary trunk and SVC
-It stabaliezes the position of the heart and prevents overstretching
20
Q
What are the charecteristics of the serous pericardium?
A
It is a thinner, more delicate layer
21
Q
What are the layers of hte heart wall?
A
- Epicardium
- Myocardium
- Endocardium
22
Q
What is the epicardium?
A
The visceral layer of the serous pericardium
23
Q
What makes up 95% of the heart wall?
A
The myocardium
24
Q
What is the myocardium made of?
A
Striated muscle
25
What is the endocardium?
The smooth inner layer that is continous with the endothelial lining of the aorta, SVC, and IVC
26
What are the 4 main parts of the heart?
1. The apex
2. The base
3. 4 chambers
4. Sulci
27
What are the 4 chambers of heart?
-2 atria
-2 ventricles
28
What are the 2 sulci of the heart?
1. The coronary sulcus
2. The interventricular sulcus
29
Where is the base of the heart directed?
Toward the right shoulder
30
What structures exit the base of the heart?
Ascending aorta and pulmonary arteries/trunk exit
31
What structures enter the base of the heart?
The SVC and IVC
32
What makes up the apex of the heart
The tip of the right and left ventricles
33
Where is the apex of the heart directed?
Towards the left hip
34
What does the coronary sulcus sepearate?
The atria from the ventricles
35
How many interventricular sulci are there?
2
36
What do the interventricular sulci separate?
The ventricles
37
What are the 2 interventricular sulci?
1. Anterior
2. Posterior
38
What are the functions of the sulci and what do they contain?
1. Separate the chambers
2. The coronary vessels travel in the sulci and the sulci contain a variable amound of fat
39
Label 1-13
1. Brachiocephalic trunk
2. SVC
3. Acending aorta
4. Right pulmonary veins
5. Right coronary artery
6. Coronary sulcus
7. IVC
8. Arch of aorta
9. Left pulmonary artery
10. Left pulmonary vein
11. Auricle of left atrium
12. Left ventricle
13. Anterior interventricular sulcus
14. Descending aorta
40
Label 1-10
1. Arch of aorta
2. Descending aorta
3. Left pulmonary veins
4. Left atrium
5. Coronary sinus (in coronary sulcus)
6. Left ventricle
7. Brachiocephalic trunk
8. Right pulmonary artery
9. Right atrium
10. Right ventricle
41
# T/F
We see the left atrium on a normal AP/PA image
FALSE
42
Where does the right atrium recieve blood from?
1. Superior vena cava
2. Inferior vena cava
3. Coronary sinus (posterior surface)
43
Where are the pectinate muscles located?
On the anterior surface of the right auricle
44
# T/F
The coronary sinus contains venous blood
True
45
What is the fossa ovalis and where is it located?
-It is the remnant of the forament ovale
-Located in the right atrium
46
Where is the tricuspid valve located and what does it open into?
Located in the right atrium and opens into the right ventricle
47
What causes the valves within the heart to open and close?
Pressure
48
What forms the papillary muscles and what do the papillary muscles connect to?
The trabeculae carneae form the papillary muscles, and the papillary muscles connect to the chordae tendineae
49
What is the function of the chordae tendineae?
It attaches the cusps of the tricuspid valve to the papillary muscles to prevent the cusps from entering into the atria and the backflow of blood into the atria during contraction of the ventricles
49
What are the 2 pulmonary arteries?
The right and left pulmonary arteries
49
What does the pulmonary valve open into?
Opens into the pulmonary trunk
50
Where does the left atrium recieve blood from?
Recieves blood from 4 pulmonary veins
51
# T/F
Blood coming from the pulmonary veins are oxygenated
True
52
Where is the mitral valve located?
In the left atrium
53
Which ventricle is thicker? Why?
The left ventricle-It is reponsible for pumping blood to the entire body
54
How many cusps does the aortic and pulmonary valve contain?
3 cusps
55
Where is the pulonary trunk in relation to the aortic valve?
It is anteior to the aortic valve
56
Label 1-7
1. SVC
2. Right atrium
3. Inferior vena cava
4. Aorta
5. Main pulmonary artery
6. Left auricle
7. Left ventricle
57
What is the most superior part of the heart?
The right atrium
58
What is the most posterior part of the heart?
The left atrium
59
What is the most inferior part of the heart?
The left ventricle
60
What is the most anterior part of the heart?
The right ventricle
61
What position of the chest would we use to acess ventricular enlargment?
Lateral
62
How much space should the heart take up behind the body of the sternum?
The heart should take up less than 33%/1/3 of the retrosternal space
63
Label 1-5
1. Pulmonary valve
2. Chordeae tendineae
3. Interventricular septum
4. Papillary muscle
5. Trabeculeae carnieae
64
What is occuring physiologically to the cusps, muscles and chambers when the mitral and tricuspid valves are open?
1. The Cusps project into the ventricle
2. The atria contract
3. Ventricles, papillary muscles, and chordae tendineae are relaxed
4. Blood enters the ventricles
65
# T/F
Blood goes from high presssure to low pressure
True
66
What is occuring physiologically to the cusps and muscles when the ventricles contract?
1. The blood forces the cusps together to close
2. The papillary muscles contract, which tightens the chorae tendineae
67
Label 1-3
1. Cusp of tricuspid valve
2. Chordae tendineae
3. Papillary muscle
68
What does each cusp of the semilunar vavles attach to?
Each cusp attaches to the arteriole wall
69
Where do the free borders of the semilunar vavles project into?
The free borders project into the lumen of the artery
70
# T/F
When the ventricles contract, the blood flows into the artery
True
71
How are the semilunar vavles closed?
When the ventricles relax, the blood flows back towards the heart and fills the free edges of the cusps, thus closing the semilunar valve
72
Label 1-8
1. AV
2. PV
3. TV
4. MV
5. PV
6. AV
7. TV
8. MV
73
What is the defenition of stenosis?
Narrowing
74
What is meant when describing an insufficient/incompetent vavle in the heart?
The failure for the valve to completely close
75
When does the foramen ovale become the fossa ovalis?
When it closes at birth
76
What is the foramen ovale?
The opening between the atria
77
What does the ductus arteriousus become once it closes at birth?
It becomes the ligamentum arteriousum
78
Where is the ductus arteriosus located?
Located between the pulmonary trunk and the distal part of the aortic arch
79
# T/F
When a baby has fetal heart, are the lungs functional?
No, the blood bypasses
80
If either the ductus arteriosus or the foramen ovale is open after birth, what can this lead to?
Can lead to pulmonary hypertension and right ventricular enlargment
81
What is being demonstrated here?
Patent ductus arteriosus
82
What is dextrocardia?
When the heart sits to the right of the body
83
What is meant by the term levocardia?
The normal position of the heart
84
What is the average weight of the heart in males and females?
Males: 310 g
Female: 225 g
85
What makes up the right heart border?
Mostly the right atrium
86
What makes up the inferior heart border?
Some of the right atrium and right ventricle across to the apex
87
What makes up the left heart border?
The left ventricle and some of the left auricle
88
Which way does the left heart border slope from the apex?
Slopes superiorly and medially from the apex
89
**Label 1-8**
1. SVC
2. Right atrium
3. Right ventricle
4. Ascending aorta
5. Pulmonary trunk
6. Coronary sulcus
7. L ventricle
8. Anterior interventricular sulcus
90
What 2 fibers make up the conduction system of the heart?
1. Contractile fibers
2. Autorythmic fibers
91
What percentage of cardiac cells do the contractile fibers make up?
Make up 99% of cardiac cells
92
What percentage of cardiac cells do the autorythmic fibers make up?
1%
93
What is the function of contractile fibers of the heart?
They are teh working fibers that are responsible for contractions
94
What is the function of the autorythmic fibers of the heart?
-They are self excitable nodal cells that generate AP, that trigger contractions
95
What are the nodal and conducting cells of the heart?
1. SA node
2. AV node
3. AV bundle
4. Right and left bundles
5. Purkinje fibers
96
What sets the intrinsic rhythm of the heart?
The cells of the SA node
97
What type of fibers does the SA node contain?
Contains autorythmic fibers
98
Where is the SA node located?
Located at the right atrial wall near the opening of the SVC
99
What is the rate of the SA node? What about at rest?
-100 beats/minute
-At rest, 70-75 bpm
100
What would happen if the SA node failed for any reason?
-The pacemaker function would shift to the AV node; which would cause bradycardia
101
What does the AV node stand for?
Atrioventricular
102
Where is the AV node located?
At the interatrial spetum, superior to the ventricles near the center of the heart
103
What is the function of the AV node?
Slows down the speed of travel of the AP
104
# T/F
The AV node has fewer gap junctions and smaller diameter fibers
True
105
Label 1-5
1. SA node
2. AV node
3. AV bundle
4. Right and left bundle branches
5. Purkinje fibers
106
What is the function of an ECG?
Monitors the electric currents generated by the heart
107
What are the 3 deflection waves on an ECG graph and how long on average are each segments?
1. P wave-.08 sec
2. QRS wave-.08 sec
3. T wave-.16 sec (slower)
108
What does the P wave represent?
1. The depolarization of both atria following contraction
109
What is occuring physiologically during the P wave with the nerve impulse?
The impulse moves from the SA node through the atria
110
**What is the QRS complex representing?**
Represents the depolarization of ventricles **and the replarization of the atria**
111
Why is the repolarization of the atria not visualized on the graph in the opposite direction?
Because the depolarization of the ventricles and the repolarization of the atria are occuring at the same time
112
What does the T-wave represent?
The replarization of ventricles
113
How does the myocardium of ventricles repolarize?
In reverse order
114
Label 1-5
| (the boxes at the bottom are refering to the type of contraction)
1. P interval
2. S-T segment
3. Q-T interval
4. Atrial contraction
5. Ventricular contraction
115
What is occuring during the PR segment?
AV nodal delay
116
What is occuring during the ST segment?
Time during which ventricles are contracting and emptying
117
What is occuring during the TP interval?
Time during which ventricles are relazing and filling
118
Label 1-3
1. PR segment
2. ST segment
3. TP interval
119
What is the average heart rate?
75 beats/min
120
What is the average cardiac cycle?
0.8 sec
121
The diastole/systole of both atria and ventricles is refered to as what?
The cardiac cycle
122
How long does atrial systole last?
.1 seconds
123
What is happening to the ventricles when the atria re in systole?
The ventriclese are diastole
124
What is occuring with the atria when the ventricles are in systole?
The atria are in diastole
125
How long does ventricular systole last?
.3 seconds
126
How much of the ventricles are passively filled?
70% (105mL) are passively filled
127
What vavles are opened and closed during atrial systole?
The AV valves are open, the SL valves are closed
128
Which way, and how much does blood flow during atrial systole?
Blood flows from the atria to the ventricles
(25 mL)
129
What does the firing of the SA node induce?
Atrial depolarization (P wave)
130
How much blood do the ventricles contain at the end of diastole? What is this called?
130 mL
-This is called the EDV
(end diastolic volume)
131
What vavles close during ventricular contraction? Why?
The AV valve closes due to increased pressure
132
What is occuring with the valves during isovolumetric contraction?
All of the valves are closed
133
When does ventricular ejection occur? What valve opens during this?
When the pressure inside the ventricle is greater than the artery
-The SL valves open
134
What is the ESV?
-Whats left inside the ventricle during systole
-60 mL
135
What valve closes during ventricular disastole?
The SL valves close
136
When the AV valves open, and blood is passively flowing from the atria to the ventricles, what stage are the atria and ventricles in?
They are in diastole
137
Which pressure is higher during ventricular diastole; the pressure in the ventricles, or the pressure in the atria?
The pressure in the atria
138
Label 1-4
1. Pulmonary valve (open)
2. Bicuspid valve (closed)
3. Aortic valve (open)
4. Tricuspid valve (closed)
139
Label 1-6
1. Pulmonary valve (closed)
2. Left coronary artery
3. Bicuspid valve (open)
4. Right coronary artery
5. Aortic valve (closed)
6. Tricuspid valve (open)
140
Label 1-11
1. Pulmonary trunk
2. Pulmonary valve
3. Pectinate muscle of left atrium
4. Left coronary artery
5. Bicuspid valve
6. Ascending aorta
7. Right coronary artery
8. Pectinate muscle of right atrium
9. Aortic valve
10. Tricuspid valve
11. Coronary sinus
141
What are the 3 factors that affect stroke volume?
1. Preload
2. Contractility
3. Afterload
142
What is preload?
The degree of stretch on the heart before it contracts
143
What is contractility?
The forcefulness of contraction
144
What is the afterload?
The pressure tha must be exceeded before ejection of blood from the ventricles can occur
145
What happens when the right ventricle starts systole?
1. Tricsupid valve closes
2. Pulmonary valve doesnt open until isometric volume occurs
146
What is the function of stroke volume?
Ensures that the left and right ventricles pump the same amount of blood
147
What is the law that describes how preload works?
The frank-starlings law
148
What is the relationship between preload and EDV?
Preload is proportional to the EDV
149
# T/F?
Greater stretch or preload leads to a greater contraction?
True
150
What is the main function fo the preload?
To keep the 2 ventricles in balance
151
What are the 2 factors that EDV is affected by?
1. Duration of ventricular diastole (filling time)
2. Venous return
152
What catagory of drugs increases contractility?
Adrenergic drugs
153
What decreases contractility of the heart?
1. Calcium channel blockers
2. Anoxia
3. Acidosis
154
What increases the contractility of the heart?
1. Increased Ca+ levels
2. Adrenergic drugs
3. Sypmathetic division
4. Epinephrine and norepinephrine
155
What is the afterload pressure in the vessel after the right ventricle?
20mmHg
156
What is the afterload pressure in the vessel right after the left ventricle?
80mmHg
157
Will an increasing afterload cause an increase, or decrease in stroke volume?
It will cause a decrease in stroke volume
158
What can an increased afterload be caused by?
1. Hypertension
2. Atherosclerosis
159
What is atherosclerosis?
High blood pressure caused by build up of plaque
160
What has a direct affect on cardiac output?
Changes in either SV or HR
161
# T/F
Anything that affects the stroke volume or heart rate will have an affect on the cardiac output.
True
162
How do you measure the actual stroke volume?
Catheterization
163
What are some factors that may modify heart rate?
1. Chemical influences
2. Neural influences
3. Age
4. Gender
5. Physical fitness
6. Body temp
| (only name 3)
164
What centers do the medulla oblongata contain?
1. Respiratory center
2. Cardiovascular center
165
What is the function of chemoreceptors?
They detect chemical changes
166
What is the function of baroreceptors?
Measuring the stretch or pressure on the vessel; sending the information back to the medulla oblongata
167
What happens if the SA and the AV node fails?
The heart rate slows down, and the individual will need a pacemaker
168
What are the 2 systems of the ANS?
1. Sympathetic
2. Parasympathetic
169
What are the four things that play a large role in nervous control of heart rate?
1. The medulla oblongata
2. The ANS
3. Chemoreceptors
4. Baroreceptors
170
What is the first part of the internal carotid artery?
The carotid sinus
171
What 3 things control the chemical regulation of heart rate?
1. Epinephrine and norepinephrine
2. Exercise, stree and excitment
3. Adrenal glands
172
# T/F
Exercise, stress and excitement stimulates the release of more hormones, which in turn decreases the heart rate and strength of contraction.
False; Exercise, stress and excitement stimulates the release of more hormones, which in turn **increases** the heart rate and strength of contraction.
173
Define arteries:
They carry blood away from the heart
174
Define veins:
They carry blood to the heart
175
What is the function of the capillaries?
They exchange vessels
176
What are the 2 systems of circulation?
1. Pulmonary
2. Systemic circulation
177
How are circuits in pulmonary and systemic circulation arranged?
They are arranged in series
178
What does starlings law ensure when it comes to circuits?
It ensures that the same volume of blood flows into each circuit
179
# T/F
The output of one circuit becomes the input of the other
True
180
What is the pump of the pulmonary system?
The right side of the heart
181
# T/F
Deoxygenated blood from the body is pumped out the pulmonary trunk to the pulmonary arteries.
True
182
How is oxygenated blood returned to the left atrium?
Via the four pulmonary veins
183
What is the pump of the sytemic circulation system?
The left side of the heart is the pump
184
Where is oxygenated blood pumped in the systemic circulation system?
Pumped to the entire body
185
Where is deoxygenated blood pumped in sytemic circulation?
It is returned to the right atrium
186
What is the pathway of blood srarting at the right atrium?
1. Right atrium
2. Tricuspid valve
3. Right ventricle
4. Pulmonary valve
5. Pulmonary trunk and pulmonary arteries
6. In pulmonary capp
7. Pulmonary veins
8. Left atrium
9. Bicuspid valve
10. Left ventricle
11. Aortic valve
12. Aorta and systemic arteries
13. Systemic cappillaries
14. SVC, IVC or coronary sinus
187
# T/F
In systemic cappillaries, blood gains O2, and looses CO2
False; in cappilaries, blood looses O2 and gains CO2
188
# T/F
The right atrium does not have to contract for the blood to go into the right ventricle because of passive blood flow into the right ventricle
True
189
What are the 2 coronary arteries?
1. Right coronary artery
2. Left coronary artery
190
What is the function of coronary circulation?
To supply blood to the muscles of the heart
191
What does sinus mean?
A localized area that is swollen
192
When the heart contracts, does blood flow in the coronary arteries?
No
193
When does blood flow in the coronary arteries? Why?
Blood flows in the coronary arteries when the heart relaxes since high blood pressure in the aorta propels it along
194
Does blood flow in the coronary arteries when the ventricles contract?
No
195
What is the first artery to come off the ascending aorta?
The coronary arteries
196
What are the 2 sections of the left coronary artery?
1. The circumflex branch
2. The Left anterior descending branch
197
What sulcus does the LAD branch make up?
The anterior interventricular sulcus
198
What sulcus does the posterior descending artery make up?
The posterior interventricular sulcus
199
What sulcus does the circumflex branch make up?
Makes up the coronary sulcus
200
What sulcus does the marginal branch make up?
The coronary sulcus
201
What is the function of the LAD branch?
Supplies oxygenated blood to the walls of both ventricles
202
What is the function of the circumflex branch?
Supplies oxygenated blood to the walls of the left ventricle and atrium
203
What is the function of the PDA branch?
Supplies oxygenated blood to the walls of both ventricles
204
What is the function of the barginal branch?
Supplies oxygenated blood to the wall of the right ventricle
205
What are the 2 parts of the right coronary artery?
1. Posterior interventricular branch/ PDA
2. Marginal branch
206
What is an anastomoses?
Many arterial collateral routes that provide protection by having built in extra circulation of vessels that go to the same area
207
**Where does all venous blood enter?**
The coronary sinus
208
Where does the venous blood go to after entering the coronary sinus?
The right atrium
209
What is stroke volume?
Amount of blood pumped out of the heart each beat
210
How do you calculate the SV?
SV = EDV (End Diastolic Vol) – ESV (End Systolic Vol)
211
What is the cardiac output?
The amount of blood pumped out by each side of the heart in 1 min
212
How do you calculate cardiac output?
CO = HR(bpm) x SV(mL/b)
213
What is being demonstrated here?
Dextrocardia
214
What pathology is being shown here?
Cardiomegaly
