Cardiovascular System Flashcards
(162 cards)
1
Q
The heart is the central organ of the _____ system
A
cardiovascular
2
Q
The heart is mainly composed of ____ muscle, which forms a ___, divided into __ chambers.
A
cardiac muscle; sac; 4 chambers
3
Q
The heart is enclosed within the pericardium, forming part of the _______.
A
mediastinum (the portion that separates the two pleural cavities)
4
Q
What are the layers of the heart from without -> inwards?
A
pericardium ->
epicardium ->
myocardium ->
endocardium ->
5
Q
The pericardium is also known as the:
A
heart sac (deeply invaginated)
6
Q
The pericardium encloses what 3 things?
A
- heart
- pericardial fluids
- great vessels
7
Q
What is the fibrous covering of the heart?
A
The pericardium
8
Q
The capillary cleft contains a small amount of ____ fluid (liquor pericardii)
A
serous fluid
9
Q
What is the function of the serous fluid in the capillary cleft?
A
To facilitate the movement of the heart against the pericardium
10
Q
What are the 2 layers of the pericardium?
A
- parietal pericardium (fibrous layer- tough outside layer)
- visceral pericardium/epicardium (serous pericardium- thin inside layer)
11
Q
The pericardium requires blood supply from which 2 arteries?
A
- pericardiocophrenic artery
- internal thoracic artery
12
Q
What is between the serous and visceral pericardium?
A
pericardial fluid (serous fluid)
- it helps reduce friction and comes from mesothelial cells that line the epicardium and pericardium
13
Q
What is hydropericardium (same thing as pericardial effusion)?
A
The accumulation of fluid in the pericardial space.
Can result from:
- infection
- inflammation
14
Q
What is cardiac tamponade?
A
When abnormal amounts of fluid accumulate in the pericardial sac, compressing the heart and leading to a decrease in cardiac output and shock.
Caused by hydropericardium/ pericardial effusion
15
Q
The atrial face (facies atrialis) is the ____ side of the heart.
A
right side
16
Q
The auricular surface (facies auricularis) is the ____ side of the heart.
A
left side
17
Q
Which ventricle does not extend to the level of the apex?
A
The right ventricle
18
Q
What side of the heart is the subsinousal interventricular groove present on?
A
both the right and left
19
Q
what is the heart enclosed by
A
the pericardial sac within the thoracic cavity in the pericardium, which is part of the mediastinum, the partition between the two pleural cavities
20
Q
how is the heart described
A
hollow, muscular organ that circulates blood
21
Q
what are the three layers of a blood vessel, and what are they made of
A
- tunica intima: thin layer of endothelial cells
- tunica media: smooth muscle and elastic fibers
- tunica externa: collagenous outer layer with elastic fibers
22
Q
does the heart have a serosa or an adventitia
A
Adventitia- because it is outside of the two serosal coverings of the lungs within the mediastinum
23
Q
what are the 4 chambers of the heart
A
right atrium, right ventricle, left atrium, left ventricle
24
Q
what is the pericardium
A
the fibroserous covering of the heart; a deeply invaginated sac with its lumen, the pericardial cavity, being reduced to a capillary cleft
25
what is contained within the pericardial cavity
a small amount of serous fluid which facilitates movement of the heart against the pericardium
26
pericardial fluid volume is directly analogous to _____________
animal size
27
what is the average volume of pericardial fluid in dogs vs humans
dogs: 0.5-2.5 mL
humans: 15-35 mL
28
what is pericardial effusion/hydropericardium
disease condition in which the volume of pericardial fluid is higher than normal
29
what is the result of pericardial effusion
more pressure on the heart, which limits the dilation of the heart and reduces the volume of blood that is able to enter during filling
30
what causes pericardial effusion
infection, inflammation, trauma to the heart, idiopathic/iatrogenic, or genetic defects
31
what is cardiac tamponade
decrease in cardiac output
32
what is pericarditis
presence of inflammatory cells in the pericardial fluid, usually accompanied by pericardial effusion
33
what is the most common pericardial disease
pericarditis
34
What are the 6 functions of the pericardium?
- reduce friction between the heart and the pericardial sac
- lubricates
- fixes the heart
- prevents overfilling
- physical protection
- prevents the heart from infection
35
what are the two layers of the pericardial sac
1. fibrous, parietal outer surface that is visible upon opening of the thoracic cavity
2. serous, visceral layer that is the inner layer contacting the heart itself
36
what are the two parts of the serous, visceral pericardium
parietal and visceral, visceral part directly covers the heart and gives it the shiny appearance
37
what do the two portions of the serous, visceral pericardium have in common
they are both lined by mesothelial cells which produce the pericardial fluid
38
what 4 things are enclosed by the pericardium
the heart, pericardial space, pericardial fluid, and great vessels
39
What 2 arteries supply the pericardium?
the internal thoracic artery and the pericardiacophrenic artery
40
What is the pericardium innervated by?
the phrenic nerve via its attachment to the tendinous center of the diaphragm in the cupula region
41
describe the base of the heart
lies dorsal; area from which the great vessels protrude
42
describe the apex of the heart
formed by the left ventricle; the ventral point of the heart
43
describe the apex beat of the heart
Most of the surface of the heart is covered by the lung, although the heart can easily be heard on auscultation and felt through the thoracic wall: apex beat
44
The aorta points towards which border of the heart?
caudal border
45
What is the right surface of the heart called? Why?
the atrial face because the atria are more visible on the right side of the heart
46
What is the right interventricular groove (subsinuosal interventricular groove)?
A groove that demarcates the septum which separates the left and right ventricles on the right side of the heart
contains the subsinuosal interventricular artery and vein that supply the ventricles via the ventricular branches
47
what is the left surface of the heart called and why
the auricular surface because the auricles of the atria are more visible on the left side of the heart
48
What is coming off of the right ventricle,but is visible on the left surface of the heart?
the pulmonary trunk
49
What is an auricle?
extension/recess of the atria; the "ear" of the atrium
50
What is the left interventricular groove (paraconal interventricular groove)?
demarcates the septum that separates the left and right ventricles on the left surface of the heart
51
what is the intermediate groove
groove that is prominent in bovine on the left side of the heart
52
what is the coronary groove
A groove that marks the separation between the atria and ventricles
contains large amounts of fat which surround the coronary blood vessels and marks the separation of the thinner muscles of the atria from the much thicker muscles of the ventricles by a fibrous/cardiac skeleton
53
what is the function of the cranial and caudal vena cava
brings blood into the right atrium from the rest of the body
54
What 3 places does the cranial vena cava drain from?
head, neck, and forelimbs
55
What 4 places does the caudal vena cava drain from?
thorax, abdomen, pelvis, hindlimbs, etc.
56
Which ventricle is thinner- the right or the left?
the right is thinner than the left
57
what is the best way to be able to tell which side of the heart you are looking at
on the left side you will see the complete formation of the apex of the heart by a single ventricle
58
what is a pericardiocentesis
procedure in which pericardial fluid is drained via a needle
59
on which side of the body should a pericardiocentesis be performed and why
Should be performed on the RIGHT side so as to avoid hitting the major coronary vessels on the left side of the heart
the myocardium is thinner on the right side, and the fluid will accumulate more on the right side due to the size and position of the heart
60
where do you want to insert the needle when performing a pericardiocentesis
on the right side of the body at the 5th or 6th intercostal space just above the costochondral junction
61
What is the function of the pulmonary trunk?
carries blood from the right ventricle towards the lungs, where it branches into a left and right pulmonary artery (one for each lung)
62
what are the three parts of the aorta
- aortic arch
- thoracic aorta
- abdominal aorta
63
What chamber of the heart does the aorta come off of?
the left ventricle
64
what is the primary blood supply to the entire body
the aorta
65
what is the first branch of the aorta after it exits the left ventricle
the coronary arteries, which feed the heart itself within the coronary groove
66
What is the second branch of the aorta after it exits the left ventricle?
brachiocephalic trunk, which moves cranially to supply the forelimb via the subclavian artery and the head region via the right and left common carotid arteries
67
What is another name for the ligamentum arteriosum?
| this joins the aortic arch to the pulmonary trunck
butalli's ligament/ duct
68
what is the function of the ligamentum arteriosum
joins the aortic arch to the pulmonary trunk
69
what is the ligamentum arteriosum formed by
it is a remnant of the fetal ductus arteriosus
70
what happens to the ductus arteriosus immediately following birth
when the newborn starts to breathe, the tunica media of the ductus arteriosus and the inner tunic start to transform; normally the lumen of the vessel is obliterated within the first week postpartum
Once it it closed, blood is forced into the pulmonary arteries to supply blood to the lungs
71
what is persistent ductus arteriosus
congenital anomaly in which the ductus arteriosus fails to close after birth
72
what is patent foramen ovale
failure of the closure of the foramen ovale after birth; "hole in the heart"
73
what is the foramen ovale
hole between the left and right atria in the fetal heart
74
what is persistent right aortic arch
condition common in animals such as GSD's in which the ascending aorta develops from the right aortic arch instead of the left, and ends up wrapping around the esophagus and trachea, causing constriction.
75
what happens in the case of persistent right aortic arch
the ligemtnum arteriosum crosses the dorsal aspect of the esophagus, causing a partial obstruction that can lead to the formation of a diverticulum
76
what clinical signs are seen in the case of persistent right aortic arch
regurgitation of food material as the puppy begins eating solid food after weaning
77
how is persistent right aortic arch treated
surgical dissection of the impinging ligament will correct the defect, although many animals can be managed without the need for surgery
78
What is the intervenous tubercle
ridge-like structure that is found in the inner wall of the atrium that demarcates the two vena cava (cranial & caudal)
79
what is the function of the intervenous tubercle
prevents blood coming from the cranial vena cava from going into the caudal vena cava and vice versa, and redirects it into the right atrium
80
what is the interventricular septum
partition between the left and right ventricle; triangular in shape
81
what is the function of the interventricular septum
primary role is to demarcate between deoxygenated and oxygenated blood; it also plays a huge mechanical role in the pumping of blood out of the ventricles
82
What 2 arteries supply the interventricular septum?
right and left coronary arteries
83
what are the two parts of the interventricular septum
membranous part dorsally and muscular part ventrally
84
The condition referred to as "hole in the heart" can include defects in which areas of the heart?
- atrial or ventricular septal defects
- atrioventricular septal defects
- patent ductus arteriosus
85
What is the most common septal defect?
ventricular septal defect (VSD)
86
which is the most common type of ventricular septal defect
membranous is the most common
87
what are the causes of ventricular septal defects
can be acquired due to trauma or disease, or it can be genetic
88
what are the signs of a hole in the heart
difficulty breathing, blue skin/lips, pale mucous membranes, increased heart rate, and fatigue
89
why do we see an increased heart rate in the case of a hole in the heart
Increased heart rate because, due to the mixture of deoxygenated and oxygenated blood, the heart has to work harder to properly oxygenate the body
90
What is the trabecular septum?
irregular muscular ridge that is an extension of the intraventricular septum and extends from the septum to the ventricular walls
91
what is the function of the trabecular septum
Prevents overfilling of the ventricles by keeping the ventricles close to the wall of the septum
92
What are the 3 valves/ leaflets of the tricuspid valve (right AV valve)
- Septal cusp in the middle (associated with the ventral septum)
- parietal cusp above the middle (toward the ventricular wall)
- angular cusp (forms a triangle shape with the other two)
93
what is the function of the tricuspid valve
controls the flow of blood from the right atrium to the right ventricle
94
what is another name for the tricuspid valve
right atrioventricular valve
95
how is the opening and closing of the valves of the heart controlled
each cusp is connected via chordae tendineae to the papillary muscles of the ventricular wall
96
describe the opening and closing of the atrioventricular valves
valves open to allow blood flow from the atrium into the ventricles during diastole, and valves close during systole to prevent backflow from the ventricle back into the atrium
97
what is a leaky tricuspid valve
tricuspid regurgitation/backflow that is due to the valve failing to close properly during ventricular systole
## Footnote
[https://www.youtube.com/watch?v=NAxlnkp-8NM](http://)[](http://)
98
What different conditions result in a leaky tricuspid valve?
Ebsteiin's anomaly (congenital) , trauma to the chest, or infection such as endocarditis
99
What does a leaky tricuspid valve cause?
- increased heart beat to try to send more blood to the lungs as a result of the backflow
- overworks the heart
- decreased amount of blood going to the lungs for reoxogination
100
what are the chordae tendineae of the heart
strong, fibrous connections between the valve leaflets and the papillary muscles that help fix the cusps to the walls of the ventricles and maintain a one-way flow of blood in the heart
101
what is the pulmonary valve
semilunar-shaped valve made up of connective tissues and a thin and smooth mucous membrane called the endocardium which allows blood to move from the heart to the lungs to be oxygenated
102
how many pulmonary valves are there and what are they called
3:
- intermediate
- right
- left
103
describe the actions of the pulmonary valve to either allow or prevent blood flow
relaxes to expand and allow blood into the pulmonary trunk, extends to close off the ventricle;
relaxation is necessary for blood to leave the heart and extension is necessary to prevent back flow
104
alteration of the normal function of the pulmonary valve causes what
pulmonary regurgitation or stenosis, which is the failure of proper relaxation or extension
105
what are the characteristic heart sounds due to
closing of the valves of the heart
106
What produces the first heart sound sound/ lub?
atrioventricular valves closing
107
What produces the second heart sound sound/ dub?
pulmonary and aortic valves closing
108
what is the scientific name for heartworms and where do they collect within the heart
Dirofilaria immitis, they collect in the pulmonary trunk
109
how long can dogs and cats live with heartworm disease
dogs: about 7 years
cats: about 3 years
110
What does left ventricular contraction do?
forces/pushes oxygenated blood through the aorta to be distributed to the entire body
111
what is left sided heart failure and what does it lead to
left side of the heart is weakened and unable to pump oxygenated blood, so the heart has to work harder, which leads to hypertrophy
112
what does the aortic valve allow for
passage of blood from the left ventricle to the aorta
113
what is another name for the pulmonary valve
semilunar valve due to the half-moon shape of the valves
114
what are the openings that can be seen just past the aortic valve right at the coronary groove
openings into the coronary arteries as well as the brachiocephalic trunk
115
True or false: the aortic valve can experience similar stenosis and regurgitation to that of the pulmonary valve
true
116
what is the job of the left coronary artery
supplies blood to the left side of the heart (LV and LA) and divides into branches that supply the front of the left side of the heart
117
what is caused by a blockage of the coronary artery
weakness, difficulty breathing, etc.
118
what are the 4 branches of the left coronary artery
- left main trunk
- left anterior descending artery
- left circumflex artery
- right coronary artery
119
What 4 things does the valve apparatus of the mitral valve consist of
- Mitral annulus: edges of the valve
- Papillary muscles
- Anterior and posterior leaflets
- Chordae tendineae
120
where does the bicuspid valve get its name
only two leaflets as opposed to 3
121
what is another name for the bicuspid/mitral valve
left atrioventricular valve
122
what is the ossa cordis
- fibrocartilaginous structure between the left ventricle and aorta
- well developed in bovine and camels, heart cartilage in horses and pigs
- It supports the aortic valve and the tricuspid valve
123
what is the function of the ossa cordis
provides support to the heart and its valves (aortic + tricuspid)
124
how is the ossa cordis described and where is it located
a fibrocartilaginous structure located between the left ventricle and aorta
| labeled as #1, dorsal aspect with atria removed
125
what is the conducting network of the heart
Specialized network of special cells that have the ability to generate and transmit impulses through the heart muscle
126
what does the conducting system of the heart do
- Induce contraction and the pumping of blood
- Help to regulate the rhythm of the heart
127
what is the SA node
"pacemaker" of the heart that is situated on the right atrium and generates each heart beat impulse
128
what is the AV node
node located within the interatrial septum that delays the passage of the impulse from the atrium to the ventricle for a brief period until the atrial contraction is complete, so that the atria and ventricles aren't contracting at the same time
129
what is the bundle of His
connection point between the AV node and the purkinje fibers
130
what are the purkinje fibers
situated throughout the left and right ventricles that transmit electrical impulses to the ventricles to bring about coordinated contraction
131
what does damage to any component of the conducting system of the heart cause
- disruption of the cardiac rhythm
- irregular heart beat
- sometimes even heart failure
132
describe the cardiac nerves
Sympathetic and parasympathetic innervations that intermingle in the region craniolateral to the heart, sometimes called the cardiac plexus
133
What is the origin of the sympathetic nerves that innervate the heart?
T1-T5
134
the postganglionic fibers of sympathetic nerves that innervate the heart have their synapses where
either at the cervicothoracic or middle cervical ganglion
135
what are the two types of sympathetic nerves that innervate the heart and what is the function of each
accelerator: increases the heart rate
augmentor: increases the strength of myocardial contraction
136
describe the branching of the vagus nerve for the parasympathetic innervation of the heart
cardiovagal branches depart the parent nerve just caudal to the origin of the recurrent laryngeal nerve, the right goes to the SA node and the left goes to the SA node and the AV node
137
what is the function of the parasympathetic nerves of the heart
decrease heart rate and contractility
138
what are the 4 main variations seen in the comparative anatomy of the heart
1. size/shape
2. great vessels
3. apex
4. fat deposits
139
describe the size/shape differences in the heart of the following species: dog, pig, sheep, cat
- dog: ovoid in shape and more rounded than other species
- pig: "valentine heart" shape
- sheep: conical shape
- cat: rounded
140
describe the apex of the heart in the following species: dog, pig, sheep, cat
- dog: rounded
- pig: blunt
- sheep: more pronounced
- cat: blunt, slightly pointed
141
describe how the ascending aorta is different among different species
the termination pattern of the brachiocephalic trunk varies:
- in horses and ox, it terminates in both a left and right common carotid artery as well as a left and right subclavian artery
- in dogs and pigs, it terminates in a left and right common carotid artery and only a right subclavian artery; the left emerges directly from the aorta instead
142
which species has a significantly larger fat deposit on the outside of the heart muscle
ruminants
143
what is the anatomical location of the heart in dogs and cats
dogs: 4th-6th intercostal spaces
cat: 3rd/4th-6th/7th ribs
144
what is the role of epicardial fat in ruminants
Epicardial fat protects and supports the heart to exert its normal function
145
what can excess fat buildup at the base of the heart cause
coronary atherosclerosis (coronary artery disease)
146
where can the apex beat of the heart be heard in dogs
- Left: 4th to 5th intercostal space (optimal is the 5th)
- Right: 4th to 5th intercostal space
147
where can the apex beat of the heart be heard in ruminants
- Left: 3rd to 5th intercostal space (optimal is 4th)
- Right: N/A
148
where can the apex beat of the heart be heard in horses
- Left: 3rd to 6th intercostal space (optimal is 5th)
- Right: 3rd to 4th intercostal space
149
how does the vertebral artery act as a bypass
alternative for the blood supply to the brain in place of the internal carotid artery
150
how does the azygos vein act as a bypass
alternative to the cranial and caudal vena cava
151
what is the primary drainage for the thoracic and abdominal walls
azygos vein
152
how is the azygos vein formed embryologically
by 2 lumbar veins, and it passes through the aortic hiatus to get to the thorax
153
describe the formation of the azygos vein in dogs, cats, and horses
the left azygos vein degenerates and the right azygos vein persists and goes into the cranial vena cava
154
describe the formation of the azygos vein in pigs
In pigs, the right degenerates and the left persists, goes into the coronary sinus
155
describe the formation of the azygos vein in ruminants
both the left and right azygos veins persist; left goes into the coronary sinus, right goes into the cranial vena cava
156
what are the 3 main veins responsible for drainage of the thorax
- azygos vein
- intercostal veins
- internal thoracic vein
157
describe the path of drainage of the intercostal veins
drain into the azygos vein, which drains into the cranial vena cava
158
describe the path of drainage of the internal thoracic vein
drains into the brachiocephalic vein, which drains into the cranial vena cava
159
what are the names of 4 veins that drain into the azygos vein
- Lumbar vein
- intercostal vein
- costoabdominal vein
- bronchoesophageal vein
160
where does the right azygos vein bring deoxygenated blood from
chest wall, esophagus, spinal cord, mediastinum, and abdominal wall
161
where is the location of oxygenated blood sampling in the area of the thorax and what is its landmark
blood from the axillary artery can be sampled with its landmark at the cranial border of the first rib where it wraps around
162
what is the anatomical location of the heart in bovine
runs from the point of the elbow (olecranon) to the point of the shoulder (greater tubercle)
