Cardiology System Intro Flashcards
1
Q
What is function of CVS?
A
- Deliver nutrients and oxygen to cells
- Remove waste products from cells
- Maintain constant internal environment (homeostasis)
2
Q
What does aorta branch into?
A
Aorta –> smaller arteries –> smaller arterioles –> capillary beds
3
Q
What happens at capillary beds?
A
Gas exchange occurs
4
Q
How do capillary beds turn into veins?
A
Capillary bed –> venules –> veins –> superior/inferior vena cava
5
Q
What are the 2 circulations of the CVS?
A
- System (to and from body)
- Pulmonary (to and from lungs)
6
Q
What are the 2 functional parts of CVS?
A
- Conducting
- Exchange
7
Q
What forms the conducting part of the CVS?
A
Vasculature (tubes) –> arteries + veins, away and towards heart
8
Q
What forms the exchange part of the CVS?
A
Capillary beds (where diffusion occurs). Link smallest arterioles to smallest venules which forms continuous exchange system
9
Q
What is the valve between the right atrium and right ventricle called?
A
Right atrioventricular valve –> tricuspid valve
10
Q
Where does right ventricle eject blood into?
A
Pulmonary trunk
11
Q
What does right pulmonary trunk divide into?
A
Right and left pulmonary artery going towards lungs for reoxygenation
12
Q
What are the pectinate muscles?
A
Elevations in the atria walls that are important for contraction of atria. Prevents atria from over distending.
13
Q
What can the heartbeat be divided into?
A
- Diastole
- Systole
14
Q
What is the diastole part of the heartbeat?
A
Atria and ventricles relax and fill with blood
15
Q
What is the systole part of the heartbeat?
A
Atria contract (atrial systole) and push blood into ventricles. As atria start to relax, ventricles contract (ventricular systole) and pump blood out of heart.
16
Q
How many layers of tissue does the heart consist of? What are they?
A
3
- Epicardium
- Myocardium
- Endocardium
17
Q
What is job of epicardium?
A
Protective layer mostly made of connective tissue
18
Q
What is job of myocardium?
A
Muscles of the heart
19
Q
What is job of endocardium?
A
Lines the inside of the heart and protects the valves and chambers
20
Q
How is blood taken back to heart from lungs after reoxygenation?
A
Via pulmonary veins (to left atrium)
21
Q
What is the oracle on top of atria?
A
Extra bit of space to receive extra blood when needed
22
Q
What is the internal septum?
A
23
Q
What is the internal septum?
A
Prevents blood from mixing by separating right and left atrium (shows atria come from 2 different embryological developments)
24
Q
What are the Crista terminalis?
A
Eleveations which separates smooth and rough parts of the atria
25
What is the fossa ovalis?
Indentation which is important in foetal circulation
26
What is the coronary sinus?
A collection of veins joined together to form a large vessel that collects blood from myocardium. Delivers deoxy blood to right atrium (along with superior and inferior vena cava)
27
What are the the chordae tendineae (heart strings)?
Fibrous cords of connective tissue that connect papillary muscles to tricuspid valve and mitral valve in heart
When ventricles contract, chords prevent permeation into atria --\> holds leaflets taut during ventricular systole so no backflow
28
What is function of a heart valve?
Allows blood to flow only in one direction through heart
29
What are the 4 valves in the heart?
- 2 atrioventricular valves
- 2 semilunar valves
30
What are the 2 AV valves? Where are they? What is their purpose?
1. Mitral valve (bicuspid valve)
2. Tricuspid valve
Between the upper chambers (atria) and lower chambers (ventricles). Prevent backflow from ventricles to atria during systole.
31
What are the SL valves? Where are they?
1. Aortic valve
2. Pulmonary valve
In arteries leaving the heart
32
What side are the mitral (bicuspid) and aortic valve on?
Left heart
33
What side of the heart is the tricuspid and pulmonary valve in?
Right side of heart
34
What is function of tricuspid valve?
Prevents backflow of blood from right ventricle into right atrium
35
How many cusps does tricuspid/bicuspid valve have?
Tricuspid --\> 3 cusps (anterior, posterior, septal)
Bicuspid --\> 2 cusps (anterior, posterior)
36
How are AV valves anchored to walls of ventricles?
By chordae tendinae
37
What are the chordinae tendinae attached to?
Papillary muscles
38
What is the name of the papillary muscles and chordae tendinae together? What is their function?
Subvalvular apparatus --\> keep the valves from prolapsing into the atria when they close. BUT have no effect on opening and closing of valves
39
What is opening and closing of valves caused by?
Pressure gradient across the valve
40
What is function of mitral valve?
Allows blood to flow from left atrium to left ventricle
41
What is the ascending aorta?
Portion of the aorta commencing at opening of left ventricle, on a level with the lower border of the 3rd costal cartilage behind the left half of the sternum.
42
What does ascending aorta branch into?
2 coronary arteries which supply the heart
43
Where does the left vagus nerve pass?
Anterior to the aortic arch
44
What are the 4 sections of the aorta?
1. Ascending aorta
2. Aortic arch
3. Thoracic (descending) aorta
4. Abdominal aorta
45
What is the aortic arch?
A continuation of the ascending aorta
46
What are the 3 main branches of the aortic arch?
1. Brachiocephalic trunk
2. Left common carotid artery
3. Left sublclavian artery
47
What does brachiocephalic trunk split into? What does this supply?
Ascends laterally to split into the **right common carotid artery** and **right subclavian artery.** These supply the right side of the head and neck and the right upper limb
48
What does the left common carotid artery supply?
The left side of the head and neck
49
What does the left subclavian artery supply?
The left upper limb
50
What is coarctation of the aorta?
Narrowing of the vessel which leads to increased resistance to blood flow
51
What does coarctation of aorta lead to?
Blood supply to rest of body is reduced. Leads to collateral circulation between proximal and distal aorta via intercostal and internal thoracic arteries
52
Why is blood flow to head, neck and upper limbs not compromised in coarctation of aorta?
As the vessels supplying them emerge proximal to the coarctation
53
What are the heart muscles (myocardium) fed by?
Coronary arteries
54
Where is the aortic valve?
Between the left ventricle and the aorta
55
Where is the mitral valve?
Between the left atrium and the left ventricle
56
Where is the pulmonary valve?
Between the right ventricle and pulmonary artery
57
Where is the tricuspid valve?
Between the right atrium and right ventricle
58
The human heartbeat is often described as a 'lub-DUB' sound. What is the 'lub' and 'dub' produced by?
'Lub' --\> Tricuspid and mitral valves closing
'Dub' --\> Closing of pulmonary and aortic valves
59
Where does the thoracic (descending) artery span from?
Level of T4 to T12. It continues from the aortic arch.
60
Where does the thoracic artery leave the thorax via?
The aortic hiatus in the diaphragm where it becomes to abdominal aorta
61
What are the intercostal and subcostal arteries?
Small paired arteries that branch off throughout the length of the thoracic aorta
62
What do the intercostal/subcostal arteries supply?
Intercostal --\> supply the intercostal spaces (exception of first and second which are supplied by a branch from the subclavian artery)
Subcostal --\> supply the flat abdominal wall muscles
63
Where does the aorta terminate?
Level of L4 by abdominal aorta bifurcating into the left and right common iliac arteries
64
What 2 pairs of arteries supply the limbs?
Upper limb = subclavian
Lower limb = external iliac
65
Describe the electrical conduction during a heartbeatt
1. The SA nodes (pacemaker of the heart) sends out an electrical impulse
2. The upper heart chambers (atria) contract and pump blood into ventricles
3. The AV node sends an impulse into the ventricles
4. The lower heart chambers (ventricles) contract or pump
5. The SA node sends out another signal to the atria to contract which starts the cycle over again
66
Where is the AV node?
A group of cells at the bottom of the right atrium
67
Where is the SA node?
Top of the right atrium
68
Why does the AV node slow the signal down?
So the atria ad ventricle don't contract at the same time
69
What supplies the main conducting centres of the heart?
The right coronary artery
70
What can blockage of coronary arteries lead to?
Ischaemia (reduced/inadequate blood supply) which can lead to myocardial infarction (necrosis)
71
Where does the heart reside?
In the pericardial sac
72
What is the pericardium? How many layers does it have?
The membrane enclosing the heart. 3 layers:
1. Outer fibrous layer
2. Inner double layer of serous membrane
1. One closely related to fibrous pericardium (**parietal layer** of serous pericardium)
2. Another layer lies on surface of heart (**visceral layer** of serous pericardium) or **epicardium**
73
What/where is the thymus gland?
* Lies in anterior mediastinum for short period of time (in childhood)
* Important for immune response during childhood
* As we get older, gland becomes a fatty filled structure
74
What drains into the superior vena cava?
The right and left brachiocephalic veins
75
What doe the superior/inferior vena cava empty out into?
The right atrium
76
Why does the heart move during respiration?
Pericardium attached to central part of diaphragm
77
What is the connection between the pulmonary trunk and the aortic arch called? What is the purpose of it as a foetus?
Ligamentum (closed structure in adults)
In foetal development --\> patent vessel (duct) that allows blood to pass from pulmonary trunk into arch of aorta (bypassing lungs)
78
What is base of heart formed by?
Right and left atrium
79
What is apex of heart formed by?
Predominantly by left ventricle
80
What are the 2 pericardial sinuses?
1. Transverse
2. Oblique
81
Where is the transverse pericardial sinus?
Passage between venous and arterial mesocardia
Behind the aorta and pulmonary artery and anterior to the superior vena cava
82
Why is the transverse pericardial sinus clinically important in bypass surgery?
* Put tube into aorta and tube into pulmonary trunk. Complete blockage and gather deoxygenated blood (that would usually go to lung). Reoxygenate that outside body (special machine). Put tube back into aorta and reoxygenate body.
83
Where is oblique pericardial sinus?
Lies behind left atrium and in between left and right pulmonary veins
84
What does left/right oracle of atrium act as?
Reserve when there is increased amount of blood flow back to the heart (during exercise)
85
What do all the branches of the coronary system emerge from?
Right and left coronary artery
86
What does left coronary artery branch into?
1. Anterior interventricular artery
2. Left circumflex artery
87
What is purpose of cusps/valves?
When heart relaxes, cusps catch any residual blood that tries to return to ventricle
88
What are the aortic sinuses?
Left and right aortic sinuses are dilations in the ascending aorta that are located at the level of the aortic valve
89
What do aortic sinuses give rise to?
Right and left coronary arteries emergy from aorta at aortic sinuses
90
What is the coronary sinus?
Where vast majority of coronary veins drain into (contains deoxygenated blood which then empties into right atrium
91
Nerves give branches that all intermingle together to form what?
A plexus of nerves:
- Pulmonary plexus
- Cardiac plexus
- Oesophageal plexus
92
What is a plexus?
A network of nerves or vessels
93
What side of the root of the lung does the vagus/phrenic nerve pass?
Vagus nerve --\> passes posterior to root of lung
Phrenic nerve --\> passes anterior to root of lung
94
Branches of which nerves go on to give branches to some of the plexuses?
Sympathetic chain and vagus nerve
95
Why are plexuses known as autonomic plexuses?
Have paraympathetic and sympathetic input
96
What supplies the plexuses with sympathetic imput?
Sympathetic chain
97
What supplies the plexuses with parasympathetic imput?
The vagus nerve
98
What is purpose of cusps in valves?
Pushed open to allow blood flow and which then close together to seal and prevent backflow
99
What are the aortic sinuses?
Left and right aortic sinuses are dilations in the ascending aorta that are located at the level of the aortic valve. Give rise to left and right coronary arteries that supply the myocardium.
Coronary arteries emergy from aorta at aortic sinuses
