CVS anatomy Flashcards
1
Q
what is the mediastinum
A
the midline partition of the thorax separating the right and left pleural cavities
2
Q
what does the mediastinum contain
A
heart and its great vessels thoracic trachea and bronchi thoracic oesophagus vagus nerves phrenic nerves thoracic duct
3
Q
what is the sternal angle
A
surface landmark for the division of the mediastinum into the superior and inferior division
4
Q
how is the mediastinum divided
A
into superior & inferior the inferior has 3 further subdivsions -anterior -middle -posterior
5
Q
where is the superior mediastinum and what does it contain
A
above the sternal angle
contains the great vessels of the heart and upper portions of the thoracic trachea and oesophagus
6
Q
where is the anterior mediastinum
A
between middle mediastinum and the body of the sternum.
anterior to pericardium
7
Q
where is the middle mediastinum and what does it contain
A
sits behind the body of the sternum.
contains the heart and fibrous sac of pericardium
8
Q
where is the posterior mediastinum
A
occupies area posterior to the middle mediastinum and the diaphragm
9
Q
what does the posterior mediastinum contain
A
oesophagus
azygous veins
thoracic duct
intercostal neurovascular bundles
10
Q
in which mediastinum is the heart located
A
middle
11
Q
what is the function of pericardium
A
enclose the heart in situ in the thoracic cavity.
facilitates free movement of the heart when it contracts while isolating its movement from that of the structures surrounding the thorax
12
Q
what are the 2 layers of pericardium
A
fibrous & serous
13
Q
what is the function of fibrous pericardium
A
fibrous sac, anchors the heart in place
14
Q
what are the further subdivisions of serous pericardium
A
visceral- stuck to the heart (myocardium- the heart muscle)
parietal -
15
Q
how are visceral & parietal pericardium separated
A
by a narrow fluid filled space
- pericardial space
- pericardial fluid
16
Q
where is pericardial fluid located
A
between the two layers of serous pericardium
17
Q
what is cardiac tamponade
A
where increasing volume of pericardial fluid during bleeding following trauma will interfere with the ability of the heart to contract
18
Q
which side of the heart is anterior
A
right
19
Q
which side of the heart is posterior
A
left
20
Q
what does the right atrium form
A
the entire right surface and border of the heart
1/4 of the anterior surface
21
Q
what does the right ventricle occupy and form
A
occupies most of the anterior surface
forms 2/3 of the inferior border
22
Q
what does the the left ventricle form
A
nearly all the left border and makes up large part of the posterior surface
small part on the left inferior border- apex
23
Q
what does the left atrium make up
A
entirely on the posterior aspect of the heart
24
Q
what is the sternocostal surface of the heart and what structures are visible
A
anterior aspect
right atrium
right ventricle
left ventricle
25
what is the diaphragmatic surface
inferior aspect of the heart
26
what structures are visible on the posterior surface of the heart
right and left atria and ventricles visible
27
where is the apex seen beating
in the left fifth intercostal space about 10cm from the midline
28
what does the atrioventricular groove indicate
the septum separating the two atria from the two ventricles
| runs in vertical plane
29
what does the interventricular sulcus indicate
the septum separating the right and and left ventricles
| divided into and anterior and interior aspect
30
what are the atrial and ventricular septa
connective tissue separates the right and left atria and right and left ventricles through muscular continuity maintained
31
what is the fibrous skeleton of the heart composed of
dense fibrous tissue between the atria and ventricles (corresponds to the atrioventricular grooves)
32
what is the function of the fibrous skeleton
provides opening for valves
supports and anchors valves
electrically isolates atria from ventricles except for atrioventricular bundles
33
what 3 layers does the heart wall consist of
epicardium
myocardium
endocardium
34
what is epicardium
an outer serous layer of the heart
35
what is myocardium
layer of cardiac involuntary muscles that originates and inserts into fibrous rings surrounding the valves orifices
36
what is endocardium
an inner lining of the endothelium
37
where does blood flow go after entering the sup and inf vena cava
Right atrium then right ventricle through r av opening and distributed to through the lungs by pulmonary trunk & arteries
38
how is blood distributed to the lungs
pulmonary trunks and arteries
39
how is blood returned to the heart from the lungs
pulmonary veins
40
after blood enters from the pulmonary veins where does it go
left atrium and into left ventricle through l av opening and to the body via aorta
41
what are the structures of the right atrium
```
orifice of sup vena cava
orifice of inf vena cava
crista terminalis
fossa ovalis
tricuspid valve
pectinate muscles
right auricle
coronary sinus- post
sinoatrial and av nodes
```
42
where is the fossa ovalis
right atrium above the vena cava
43
what is the function of the coronary sinus and where does it open
returns blood from the heart walls and opens into the right atrium
44
where are pectinate muscles
right atrium, they radiate out at right angles from the crista terminalis
45
what does the tricuspid (r av valve) consist of
three flaps, septa
46
what is attached the edges of the flaps of the bicuspid/tricuspid valves
chorda tendinae
47
what is crista terminalis
vertical ridge running between 2 vena cava. divides atrium into smooth and rough anterior wall
48
what drains into the right atrium as well as the sup and if vena cava
middle cardiac vein
| coronary sinus
49
where does the right coronary artery lie
in the anterior atrioventricular groove
50
where does the right ventricle receive blood from
right atrium via the tricuspid valve (r av valve)
51
what does the right ventricle contain
```
trabecula carneae
chorda tendiane
papillary muscles
pulmonary valve
pulmonary trunk
pulmonary artery
moderator band
```
52
what is the difference between trabecula carneae and pectinate muscles
pectinate muscles are in the atria and TC are in the ventricle
53
where do chorda tendineae come out from
between the tricuspid valve flaps and papillary muscles
54
what do the papillary muscles do
anchor the chorda tendineae and cusps to the heart wall
55
what valves guard the opening of the pulmonary artery
semi lunar valves
56
what does the moderator band do
in the rv and is part of the econducting system of the heart
57
where does the left atrium receive blood from
pulmonary veins from the lungs carrying o2 blood
58
what valve is in the LA
bicuspid
| L AV valve
59
what is the function of the left ventricle
pump blood to the whole body
60
what are the structures in the left ventricle
trabeculae carneae- gives roughened aspect
left av valve (biscupid/mitral)
papillary muscles
aortic valves
61
where do the papillary muscles attach
to the cusps of the bicuspid/tricuspid valves via the chorda tendineae
62
how do the papillary muscles prevent the bicuspid/tricuspid valves from everting into the atria thus preventing a backflow during ventricular systole
they contract early in advance of the rest ventricular muscle causing a tensing of the chorda tendineae
63
what does the aortic valve do
prevents back flow of blood from aorta into left ventricle
64
what are the branches of the aorta
ascending aorta
arch of aorta
descending aorta
65
what are the branches of the ascending aorta
coronary arteries
66
what are the branches of the arch of aorta
brachiocephalic
left subclavian
left common carotid
67
what are the branches of the descending aorta
bronchial arteries
oesophageal
post intercostal arteries
paired pericardial
68
where does the left coronary artery arise from
left posterior aortic sinus
69
what are the two terminal branches of the left coronary artery
anterior interventricular branch
| circumflex branch
70
where does the circumflex br of the left CA travel
to posterior aspect of heart into atrioventricular sulcus
71
where does the anterior interventricular br descend
in the sulcus towards the apex of the heart
72
what areas does the left CA supply blood to
both atria and some adjacent right ventricle
73
what happens if the left coronary artery is blocked
cardiac muscle distal blockage would no longer be supplied with blood and be irreversibly damaged (CA are end arteries)
74
what does the right coronary artery supply
right atrium & ventricle, sinoatrial node & AV node, portion of the left atrium & ventricle
75
what are the br of the right coronary artery
right marginal artery
| posterior interventricular artery
76
where does most venous blood from cardiac veins drain
coronary sinus
77
what are the major tributaries the coronary sinus receives
great cardiac vein
middle cardiac vein
small cardiac vein of the RV
78
what happens to the great cardiac vein as it approaches the atrioventricular sulcus
turns sharply posteriorly and right as the coronary sinus
79
what tributaries does the great cardiac vein receive from the left ventricle
oblique vein
| posterior vein of the left ventricle
80
when does the middle cardiac vein join the the coronary sinus
as it approaches the right atrium
81
what happens if small cardiac veins of the RV do not drain into the coronary sinus
they drain directly into the right atrium
82
which chamber of the heart does the coronary sinus drain into
right atrium
83
where do the left brachiocephalic veins drain
into the superior vena cava
84
what drains into the brachiocephalic veins
left subclavian and left int jugular veins
85
what is the function of the SA node
pacemaker- initiates heartbeat. impulse spreads over atrial walls causing them to contract and fill the ventricle
86
where is the SA node
sup aspect of crista terminalis and junction of sup vena cava and RA
87
what is the function of the AV node
pick up impulses from the atrial walls and replays the impulses down the interventricular septum via the bundle of His
88
where is the AV node
in the atrioventricular septum just above the coronary sinus
89
what is the function of the left and right atrioventricular bundles
synchronise contraction in different parts of the heart
90
what is the function of purkinje fibres
stimulate ventricular myocardium
91
what happens if there is damage to the SA node
other pacemakers act but may result in lowered heart rate or disturbed heart rhythm (arrhythmia)
92
what happens when there is damage to the AV bundles
bundle block- leads to heart failure & insufficient supply of blood to the body
93
what does it mean that the heart receives dual supply for extrinsic innervation
parasympathetic and sympathetic innervation
94
what supplies the ps innervation to the heart
vagus nerve (preganglionic axons)
95
what do the preganglionic ps fibres from left and right X reach the heart as
cardiac branches
96
where do the preganglionic fibres from X synapse
in ganglia located within the plexus or walls of the atria
97
what neurovascular bundle does X travel in
carotid sheath
98
where does the recurrent laryngeal br of X travel on the L and R
left- round aorta
| right- round subclavian artery
99
where does X exit to
abdomen
100
what stimulation does X provide
lowers heart rate- (ActCh released)
reduces force of contraction
constricts the coronary arteries
101
where do to the sympathetic nerves originate from
sympathetic chain
thoracolumbar outflow
axons in these nerves postganglionic having synapsed in ganglia apart of the sympathetic chain
102
what is the stimulation of sympathetic nerves
raises heart rate
| increases force of contraction (by releasing noradrenaline)
103
the superior mediastinum also subdivides further, what are these 3 divisiond
anterior
intermediate
posterior
104
what does the anterior part of the superior mediastinum contain (beneath sternum)
sternothyroid & sternohyoid
thymus gland
sup vena cava
brachiocephalic vein
105
what does the intermediate part of the superior mediastinum contain
aortic arches & branches
| vagus & phrenic nerves
106
what does the posterior part of the superior mediastinum contain (in front of vertebra)
oesophagus
trachea
thoracic duct
left recurrent laryngeal nerve
107
what does the vagus nerve supply in the thorax
heart
bronchi
lungs
oesophagus
108
as X passes through the diaphragm what does it supply
stomach, part of intestines as far as transverse colon, liver, kidneys and spleen
109
where does the left recurrent laryngeal nerve originate
in the thorax but returns to the neck
110
what would happen if there was damage to the left recurrent laryngeal nerve
paralysis of the muscles of that move the vocal folds, except the cricothyroid muscle
111
what structures does the phrenic nerve supply in the thorax
motor to diaphragm & sensory supply also to diaphragm and pericardium
pleura covering the mediastinum and diaphragm
peritoneum on the abdominal side of the diaphragm
112
what does the phrenic nerve cross on the right to reach the structures it supplies
right brachiocephalic vein
sup vena cava
right side of pericardial sac to reach the caval opening of the diaphragm
113
what does the phrenic nerve cross on the left to reach the structures it supplies
left subclavian artery
| left side of the pericardium to pierce the muscular part of the diaphragm
114
what joint forms at the sternal angle
symphysis
115
what would a left vocal fold paralysis indicate
damage to the left recurrent laryngeal nerve in the thorax because of advanced bronchocarcinoma
