Session 1.2i - Gray's Anatomy for Students - Thorax - Regional anatomy - Mediastinum (Part II) Flashcards
(203 cards)
1
Q
What does the right ventricle form in the heart?
A
In the anatomical position, it forms
- most of the anterior surface of the heart
- a portion of the diaphragmatic surface
2
Q
What is the orientation of the right atrium?
A
To the right of the right ventricle
The right ventricle is located in front of and to the left of the right atrioventricular orifice
3
Q
What direction does blood entering the right ventricle from the right atrium move in?
A
A horizontal and forward direction (due to the anatomical position of the right ventricle and right atrium)
4
Q
What does the outflow tract of the right ventricle lead to?
A
The pulmonary trunk
5
Q
What is the outflow tract of the right ventricle, which leads to the pulmonary trunk, known as?
A
The CONUS ARTERIOSUS (INFUNDIBULUM)
6
Q
What is the conus arteriosus also known as?
A
INFUNDIBULUM
7
Q
What is the infundibulum also known as?
A
CONUS ARTERIOSUS
8
Q
Describe the walls of the infundibulum.
A
This area has smooth walls
9
Q
Where is the infundibulum derived from?
A
The embryonic bulbus cordis.
10
Q
What is found on the walls of the inflow portion of the right ventricle?
A
Numerous muscular, irregular structures
11
Q
What are the structures found on the walls of the inflow portion of the right ventricle called?
A
TRABECULAE CARNEAE (Fig. 3.64)
12
Q
What are the trabeculae carneae?
A
Numerous muscular, irregular structures found on the inflow portion of the right ventricle (Fig. 3.64).
13
Q
How are the trabeculae carneae attached to the ventricular walls?
A
Most of these are either attached to the ventricular walls
- throughout their length; forming ridges
or
- attached at both ends; forming bridges
14
Q
What are the trabeculae carneae which only have one end attached to the ventricular surface called?
A
PAPILLARY MUSCLES
15
Q
What are papillary muscles?
A
Trabeculae carneae which only have one end attached to the ventricular surface, while the other end serves as the point of attachment for the chordae tendineae.
16
Q
One end of the trabeculae carneae attaches to the ventricular surface. What does the other end attach to?
A
The other end serves as the point of attachment for the chordae tendineae.
17
Q
What are the chordae tendineae?
A
Tendon-like fibrous cords
18
Q
Where are the chordae tendineae found?
A
At the free edges of the cusps of the tricuspid valve.
19
Q
What are the tendon-like fibrous cords found at the edges of the tricuspid valve called?
A
CHORDAE TENDINEAE
20
Q
How many papillary muscles are there in the right ventricle?
A
Three
21
Q
How are the papillary muscles named?
A
Relative to their point of origin on the ventricular surface
22
Q
What are the 3 papillary muscles in the right ventricle called?
A
- ANTERIOR
- POSTERIOR
- SEPTAL
PAPILLARY MUSCLE
23
Q
Describe the anterior papillary muscle.
A
It is the largest and most constant papillary muscle
24
Q
Where does the anterior papillary muscle arise?
A
From the anterior wall of the ventricle
25
Describe the posterior papillary muscle.
This may consist of one, two, or three structures, with some chordae tendineae arising directly from the ventricular wall.
26
Describe the septal papillary muscle.
This is the most inconsistent papillary muscle, being either small or absent, with chordae tendineae emerging directly from the septal wall.
27
What papillary muscle is the largest?
Anterior papillary muscle
28
Which papillary muscle is the most constant?
Anterior papillary muscle
29
Which papillary muscle consists of 1-3 structures?
Posterior papillary muscle
30
Which papillary muscle is the most inconsistent, being either small or absent?
Septal papillary muscle
31
What is the septomarginal trabecula?
A single specialised trabeculum (a band of connective tissue)
32
What is the septomarginal trabecula also known as?
MODERATOR BAND
33
What is the moderator band also known as?
The SEPTOMARGINAL TRABECULA
34
Where does the septomarginal trabecula lie?
Forms a bridge between the lower portion of the INTERVENTRICULAR SEPTUM and the base of the anterior papillary muscle.
35
What does the septomarginal trabecula carry?
A portion of the cardiac conduction system
36
What portion of the cardiac conduction system does the septomarginal trabecula carry?
The right bundle of the atrioventricular bundle
37
Where does the septomarginal trabecula carry the right bundle of the AV bundle to?
The anterior wall of the right ventricle
38
What closes the right atrioventricular orifice during ventricular contraction?
TRICUSPID VALVE (RIGHT ATRIOVENTRICULAR VALVE)
39
What does the tricuspid valve do?
Closes the right AV orifice during ventricular contraction.
40
What is the tricuspid valve also known as?
RIGHT ATRIOVENTRICULAR VALVE
41
What is the right atrioventricular valve also known as?
TRICUSPID VALVE
42
Why is the tricuspid valve so named?
Because it usually consists of three cusps or leaflets (Fig. 3.64).
43
What is the base of each tricuspid valve cusp secured to?
The fibrous ring that surrounds the atrioventricular orifice.
44
What does the fibrous ring that surrounds the AV orifice do?
Helps to maintain the shape of the opening.
45
Where are the cusps of the tricuspid valve continuous with each other?
Near their bases at sites termed COMMISSURES
| Google IMG: commissures heart
46
How are the tricuspid valve cusps named?
Based on their relative position in the right ventricle
47
What are the cusps of the tricuspid valve called?
ANTERIOR,
SEPTAL and
POSTERIOR CUSPS
48
What are the free margins of the tricuspid valve cusps attached to?
The chordae tendineae
49
Where do the chordae tendineae arise from?
The tips of the papillary muscles
50
When is the tricuspid valve open?
During filling of the right ventricle
51
During filling of the right ventricle, the tricuspid valve is ____
Open
52
Where do the cusps of the tricuspid valve project into when the tricuspid valve is open?
The three cusps project into the right ventricle.
53
Why do we need a compensating mechanism for the tricuspid valves?
Without the presence of a compoensating mechanism, when the ventricular musculature contracts, the valve cusps would be forced upward with the flow of blood and blood would move back into the right atrium.
54
How is blood flow prevented from moving back into the right atrium upon ventricular contraction?
Contraction of the papillary muscles attached to the cusps of the tricuspid valves by chordae tendineae prevents the cusps from being everted into the right atrium.
55
What is the function of the papillary muscles and associated chordae tendineae?
To keep the valves closed during the dramatic changes in ventricular size that occur during ventricular contraction (preventing backflow from the right ventricle into the right atrium).
56
Chordae tendinae from how many papillary muscles attach to each cusp?
Two papillary muscles
57
Why is it important chordae tendinae from two papillary muscles attach to each cusp?
This helps prevent separation of the cusps during ventricular contraction.
58
Why is it essential to have proper closing of the tricuspid valve?
This causes blood to exit the right ventricle and move into the pulmonary trunk.
59
What is the infundibulum?
The outflow tract of the right ventricle
60
What is found at the apex of the infundibulum?
The PULMONARY VALVE (Fig. 3.64)
61
What does the pulmonary valve separate>
The apex of the infundibulum (outflow tract of right ventricle) and the opening into the pulmonary trunk.
62
What does the pulmonary valve consist of?
Three SEMILUNAR CUSPS
63
Where do the free edges of the semilunar cusps (of the pulmonary valve) project into?
Upward into the lumen of the pulmonary trunk
64
What does the free superior edge of each semilunar cusp (pulmonary valve) have?
The NODULE OF THE SEMILUNAR CUSP and the LUNULA OF THE SEMILUNAR CUSP (Fig. 3.65).
65
Where is the nodule of the semilunar cusp found?
The free superior edge of the semilunar cusp (pulmonary valve)
66
Where is the lunula of the semilunar cusp?
The free superior edge of the semilunar cusp (pulmonary valve)
67
Describe the nodule of the semilunar cusp.
The middle, thickened portion of the superior edge of the semilunar cusp (Fig. 3.65)
68
Describe the lunula of the semilunar cusp.
The thin lateral portion of the superior edge of the semilunar cusp (Fig. 3.65).
69
What is the middle thickened portion of the superior edge of the semilunar cusp on the tricuspid valve called?
NODULE OF THE SEMILUNAR CUSP
70
What is the thin lateral portion of the superior edge of the semilunar cusp on the tricuspid valve called?
LUNULA OF THE SEMILUNAR CUSP
71
What are the 3 cusps of the pulmonary valve called?
LEFT,
RIGHT and
ANTERIOR SEMILUNAR CUSPS
72
How are the semilunar cusps of the pulmonary valve named?
Relative to their foetal position before rotation of the outflow tracts from the ventricles is complete.
73
What does each cusp of the pulmonary valve form?
A pocket-like sinus (Fig. 3.65) - a dilation in the wall of the initial portion of the pulmonary trunk.
74
What are the pocket-like sinuses formed by the pulmonary valve called?
PULMONARY SINUSES
75
What happens to the pulmonary sinuses after ventricular contraction?
After ventricular contraction, the recoil of blood fills these PULMONARY SINUSES and forces the cusps closed.
76
What is the function of the pulmonary sinuses?
Recoil of blood fills these sinuses and forces the cusps closed, after ventricular contraction. This prevents blood in the pulmonary trunk from refilling the right ventricle.
77
What does the left atrium form?
Most of the base or posterior surface of the heart
78
How is the left atrium derived?
As with the right atrium, the left atrium is derived embryologically from two structures.
79
What does the posterior half, or inflow portion, of the left atrium receive?
The four pulmonary veins (Fig. 3.66).
80
The four pulmonary veins enter the left atrium where?
In the posterior half, or inflow portion.
81
Describe the walls of the inflow portion (posterior half) of the left atrium,
Smooth-walled
82
What is the posterior half of the left atrium derived from?
The proximal parts of the pulmonary veins that are incorporated into the left atrium during development.
83
What is the anterior half of the left atrium continuous with?
The left auricle
84
What does the anterior half of the left atrium contain?
Musculi pectinati
85
Where is the anterior half of the left atrium derived from?
The embryonic primitive atrium
86
What separates the two components of the left atrium?
Unlike the crista terminalis in the right atrium, no distinct structure separates the two components of the left atrium.
87
What is the interatrial septum part of?
The anterior wall of the left atrium.
88
What is the thin area or depression in the interatrial septum?
The valve of the foramen ovale
89
Where is the valve of the foramen ovale located?
The thin area or depression in the interatrial septum, opposite the floor of the fossa ovalis in the right atrium
90
What is opposite the floor of the fossa ovalis in the right atrium?
Valve of the foramen ovale
91
What does the valve of the foramen ovale do during development?
Prevents blood from passing from the left atrium to the right atrium
92
What prevents blood from passing from the left atrium to the right atrium during development?
The VALVE OF THE FORAMEN OVALE
93
What occurs if the valve of the foramen ovale is not completely fused in the adult?
This leaves a "probe patent" passage between the right atrium and the left atrium.
94
What causes a "probe patent" passage between the right atrium and the left atrium of the heart?
When the valve of the foramen ovale is not completely fused in some adults.
95
Where does the left ventricle lie?
Anterior to the left atrium.
96
What does the left ventricle contribute to?
The anterior, diaphragmatic, and left pulmonary surfaces of the heart, and forms the apex.
97
How does blood enter the left ventricle?
Through the LEFT ATRIOVENTRICULAR ORIFICE
98
Where does blood flow in the left ventricle?
It flows in a forward direction to the apex
99
Describe the structure of the left ventricle.
The chamber itself is conical, is longer than the right ventricle, and has the thickest layer of MYOCARDIUM.
100
Which ventricle is longer?
The left ventricle is longer than the right ventricle.
101
Which chamber of the heart has the thickest layer of myocardium?
The left ventricle
102
The left ventricle has the thickest layer of what?
MYOCARDIUM (muscular tissue of the heart)
103
What is the outflow tract of the left ventricle known as?
The AORTIC VESTIBULE
104
What is the aortic vestibule?
The outflow tract of the left ventricle
105
Where is the aortic vestibule?
Posterior to the infundibulum of the right ventricle
106
Describe the walls of the aortic vestibule
Smooth-walled
107
Where is the aortic vestibule (outflow tract of left ventricle) derived from?
From the embryonic bulbus cordis
108
Describe the trabeculae carneae in the left ventricle.
These are fine and delicate (in contrast to those in the right ventricle).
109
What is the general appearance of the trabeculae carneae in the left ventricle.
The general appearance of the trabeculae with muscular ridges and bridges is similar to that of the right ventricle (Fig. 3.67).
110
What is observed together with the chordae tendineae?
Papillary muscles
111
What is the structure of the papillary muscles in the left ventricle?
Papillary muscles, together with chordae tendineae, are also observed and their structure is the same as the right ventricle.
112
How many papillary muscles are usually found in the left ventricle?
Two - ANTERIOR and POSTERIOR PAPILLARY MUSCLES
113
Describe the papillary muscles of the left ventricle.
They [anterior and posterior papillary muscles] are larger than those of the right ventricle
114
Where is the location of the left ventricle in relation to the rest of the heart?
In the anatomical position, the left ventricle is somewhat posterior to the right ventricle.
115
The interventricular septum forms what?
The anterior wall and some of the wall on the right side of the left ventricle.
116
The interventricular septum is described as having ___ parts: _______
Two: a MUSCULAR PART and a MEMBRANOUS PART
117
Which part of the interventricular septum is thick, and which is thin?
Muscular part - thick
| Membranous part - thin
118
What forms the major part of the interventricular septum?
The muscular part
119
What forms the upper part of the interventricular septum?
Membranous part
120
Sometimes a third part of the interventricular septum is considered an atrioventricular part. Why?
Because of its position above the septal cusp of the tricuspid valve.
121
Where is the position of the 'atrioventricular' part of the interventricular septum?
It has a superior location which places this part of the septum between the left ventricle and right atrium.
122
Where does the left atrioventricular orifice open into?
The posterior right side of the superior part of the left ventricle.
123
When is the left atrioventricular orifice closed?
During ventricular contraction
124
What closes the left atrioventricular orifice?
The MITRAL VALVE (LEFT ATRIOVENTRICULAR VALVE)
125
What is the mitral valve otherwise known as?
The LEFT ATRIOVENTRICULAR VALVE or bicuspid valve
126
What is the left atrioventricular valve otherwise known as?
MITRAL VALVE or bicuspid valve
127
What are the left and right atrioventricular valves also known as?
Left - MITRAL (bicuspid) valve
| Right - TRICUSPID valve
128
What is the bicuspid valve otherwise known as?
The MITRAL VALVE or LEFT ATRIOVENTRICULAR VALVE
129
Why is the mitral valve also referred to as the bicuspid valve?
Because it has two cusps
130
What are the cusps of the mitral valve?
(Two cusps; bicuspid valve) ANTERIOR and POSTERIOR CUSPS (Fig. 3.67)
131
What are the bases of the mitral valve cusps secured to?
A fibrous ring surrounding the opening
132
Where are the mitral valve cusps continuous with each other?
At the commissures.
133
How do the mitral valve cusps stay closed?
The coordinated action of the papillary muscles and chordae tendineae is as described for the right ventricle.
134
What is the aortic vestibule, or outflow tract of the left ventricle continuous with?
Continuous superiorly with the ascending aorta
135
What is the ascending aorta continuous with inferiorly?
The aortic vestibule (left ventricular outflow tract)
136
What closes the opening from the left ventricle into the aorta?
The AORTIC VALVE
137
What does the aortic valve separate?
The opening from the left ventricle into the aorta
138
What structure is the aortic valve similar to?
It is similar in structure to the pulmonary valve
139
What does the aortic valve consist of?
Three SEMILUNAR CUSPS
140
What is the orientation of the semilunar cusps in the aortic valve?
The free edge of each projects upwards into the lumen of the ascending aorta (Fig. 3.68).
141
What is found between the semilunar cusps and the wall of the ascending aorta?
Pocket-like sinuses
142
What are the pocket-like sinuses of the aortic valve known as?
The RIGHT, LEFT and POSTERIOR AORTIC SINUSES
143
Where do the right and left coronary arteries originate from?
The right and left aortic sinuses
144
What are the posterior aortic sinus and cusp sometimes referred to as?
The NONCORONARY SINUS AND CUSP
145
What is the noncoronary sinus and cusp?
The posterior aortic sinus and cusp.
146
Why is the posterior aortic sinus and cusp so named?
The right and left coronary arteries originate from the right and left aortic sinuses. Because of this, the posterior aortic sinus and cusp are sometimes referred to as the NONCORONARY SINUS AND CUSP.
147
What is the function of the aortic valve?
The functioning of the aortic valve is similar to that of the pulmonary valve
148
What is different about the aortic and pulmonary valve function?
The functioning of the aortic valve is similar to that of the pulmonary valve with one important additional process: as blood recoils after ventricular contraction and fills the aortic sinuses, it is automatically forced into the coronary arteries because these vessels originate from the right and left aortic sinuses.
149
After blood recoils after ventricular contraction and fills the aortic sinuses of the aortic valve, what happens?
Unlike the pulmonary valves, instead of going straight to the ascending aorta [pulmonary trunk in pulmonary valve] the left and right aortic sinuses is forced into the coronary arteries because they originate from the left and right aortic sinuses.
150
What is the cardiac skeleton?
A collection of dense, fibrous connective tissue in the form of four rings with interconnecting areas in a plane between the atria and the ventricles.
151
What sort of tissue is the cardiac skeleton?
Dense, fibrous connective tissue
152
What structure does the cardiac skeleton contain?
Four rings that are interconnected between the atria and ventricles.
153
What do the four rings of the cardiac skeleton surround?
The two atrioventricular orifices, the aortic orifice and opening of the pulmonary trunks.
154
What are the four rings of the cardiac skeleton known as?
The ANULUS FIBROSUS
155
What do the interconnecting areas of the cardiac skeleton include?
- RIGHT FIBROUS TRIGONE
| - LEFT FIBROUS TRIGONE
156
What are the right and left fibrous trigones?
Thickened areas of connective tissue
157
Where is the right fibrous trigone?
Between the aortic ring and right atrioventricular ring
158
Where is the left fibrous trigone?
Between the aortic ring and left atrioventricular ring (Fig. 3.69)
159
What does the cardiac skeleton do?
- Helps maintain the integrity of the openings it surrounds
- Provides points of attachment for the cusps
- Separates atrial musculature from the ventricular musculature
- Serves as a dense connective tissue partition that electrically isolates the atria from the ventricles
160
What does the cardiac skeleton help maintain?
The integrity of the openings it surrounds
161
What does the cardiac skeleton provide for the cusps?
Points of attachments for the cusps
162
What does the cardiac skeleton separate?
The atrial musculature from the ventricular musculature
163
Where does the atrial myocardium originate?
From the upper border of the atrioventricular rings
164
Where does the ventricular myocardium originate?
From the lower border of the atrioventricular rings
165
What does the cardiac skeleton do electrically?
Serves as a dense connective tissue partition that electrically isolates the atria from the ventricles.
166
Where does the atrioventricular bundle pass?
Through the anulus
167
What is the only connection between the atrial and ventricular myocardium?
Atrioventricular bundle
168
Where do the two coronary arteries arise?
From the aortic sinuses in the initial portion of the ascending aorta
169
What do the coronary arteries supply?
The muscle and other tissues of the heart
170
Where do the coronary arteries circle the heart?
In the coronary sulcus
171
What are the branches of the coronary arteries?
- Marginal
| - Interventricular
172
Where do the marginal and interventricular branches of the coronary arteries lie?
In the interventricular sulci
173
Where do the margin and interventricular branches of the coronary arteries converge to?
Toward the apex of the heart (Fig. 3.70).
174
Where does the returning venous blood pass through?
Cardiac veins
175
Where do most cardiac veins empty into?
The coronary sinus
176
What is the coronary sinus?
A large venous structure that is located in the coronary sulcus
177
Where is the coronary sinus found?
In the coronary sulcus
178
Where is the coronary sulcus?
On the posterior surface of the heart between the left/right atrium and left/right ventricle.
179
Where does the coronary sinus empty into?
The right atrium
180
Where in the right atrium does the right coronary sinus empty into?
Between the opening of the inferior vena cava and the right atrioventricular orifice.
181
Where does the right coronary artery originate from?
The right aortic sinus of the ascending aorta.
182
Where does the right coronary artery travel?
It passes anteriorly from the ascending aorta and then descends vertically in the coronary sulcus, between the right atrium and right ventricle (Fig. 3.71A).
183
Where is the right coronary artery located?
Anterior and vertical to the ascending aorta
184
Where does the right coronary artery lie?
In the coronary sulcus
185
What does the coronary artery do once it reaches the inferior margin of the heart?
It turns posteriorly and continues in the sulcus onto the diaphragmatic surface and base of the heart.
186
What happens before the right coronary artery reaches the diaphragmatic surface and base of the heart?
During this course, several branches arise from the main stem of the vessel.
187
Name the major branches the right coronary artery gives off.
- ATRIAL BRANCH (subsequently, SINU-ATRIAL NODAL BRANCH)
- RIGHT MARGINAL BRANCH
- POSTERIOR INTERVENTRICULAR BRANCH
188
What is the first major branch of the right coronary artery?
An early ATRIAL BRANCH
189
Where does the early atrial branch of the right coronary artery pass?
In the groove between the right auricle and ascending aorta
190
What does the early atrial branch of the right coronary artery give off?
The SINU-ATRIAL NODAL BRANCH (Fig. 3.71A)
191
Where does the sinu-atrial nodal branch of the right coronary artery pass?
Posteriorly around the superior vena cava
192
What does the sinu-atrial nodal branch of the right coronary artery supply?
The sinu-atrial node.
193
What branch is given off as the right coronary artery approaches the inferior (acute) margin of the heart?
A RIGHT MARGINAL BRANCH
194
Where does the right marginal branch from the right coronary artery?
It comes off the right coronary artery as it approaches the inferior (acute) margin of the heart (Fig. 3.71A,B)
195
What is the inferior margin of the heart also known as?
Acute
196
What is the acute margin of the heart also known as?
Inferior
197
Where does the right coronary artery travel?
It continues along the inferior (acute) border of the heart towards the apex of the heart.
198
As the right coronary artery continues on the base/diaphragmatic surface of the heart, it supplies a small branch to what?
The atrioventricular node
199
What is the base of the heart also known as?
The diaphragmatic surface
200
What is the last major branch of the right coronary artery?
The POSTERIOR INTERVENTRICULAR BRANCH (Fig. 3.71A)
201
What gives off the posterior interventricular branch of right coronary artery?
A small branch to the atrioventricular node from the right coronary artery.
202
Where does the posterior interventricular branch of right coronary artery lie?
In the posterior interventricular sulcus
203
What does the right coronary artery supply?
- Right atrium
- Right ventricle
- Sinu-atrial node (SAN)
- Atrioventricular node (AVN)
- Interatrial septum
- Portion of the left atrium
- Posteroinferior 1/3 of the interventricular septum
- Portion of posterior part of left ventricle
