cardio anatomy Flashcards
1
Q
what separates the superior and inferior mediastinum?
A
- an imaginary line that runs from the sternal angle (joint between sternal body and sternal manubrium)
- to the T4 vertebrae
2
Q
how many parts are there of the mediastinum?
A
4 parts
- superior
- inferior, which can be divided into anterior, middle, posterior
3
Q
what are the borders of the anterior mediastinum?
A
anterior border = sternum posterior border = pericardium roof = superior mediastinum floor = diaphragm lateral border = mediastinal pleura
4
Q
what are the borders of the superior mediastinum?
A
superior border = the thoracic inlet inferior bordier = inferior mediastinum anterior border = manibrium of the sternum posterior border = T1-T4 lateral border = pleurae of the lungs
5
Q
what are the borders of the middle mediastinum?
A
anterior border = anterior margin of pericardium
posterior = posterior border of pericardium
superior border = sternal angle - T4
inferior border = superior surface of diaphragm
lateral border = mediastinal pleura of lungs
6
Q
what are the borders of the posterior mediastinum?
A
lateral = mediastinal pleura anterior border = pericardium posterior border = t5-t12 roof = sternal angle to T4 line floor = diaphragm
7
Q
what are the contents of the anterior mediastinum?
A
no major structures
- thymus gland (more in children)
- lymph nodes
- internal thoracic vessels
- thyroid tissue
8
Q
what are the contents of the middle mediastinum?
A
MAIN mediastinum:
- pericardium and heart
- trachea and main bronchi
- ascending aorta
- pulmonary vessels (trunk, L&R arteries)
- brachiocephalic vessels, forming the SVC/IVC
- phrenic, left recurrent laryngeal nerve
- cardia plexus (vagus & T1-T4 sympathetic )
- tracheobronchial lymph nodes
9
Q
what are the contents of the superior mediastinum?
A
- Arch of the aorta (brachiocephalic artery, left common carotid artery, left subclavian artery)
- superior vena cava ( L&R brachiocephalic veins, , some intercostal veins)
10
Q
what are the contents of the posterior mediastinum?
A
- Oesophagus
- azygous, hemiazygous and accessory hemiazygous veins
- descending/thoracic aorta (posterior intercostal, bronchial, oesophageal, superior phrenic)
- Oesophagus plexus (L&R vagus)
- the thoracic duct
- thoracic sympathetic trunks
11
Q
what is the mediastinum?
A
area between right and left pleura
12
Q
what is the pericardium?
A
- A fibro-serous fluid filled sac
13
Q
what is the purpose of the pericardium?
A
- to separate the heart and roots of the great vessels from other mediastinal structures
14
Q
what are the layers of the pericardium?
A
- fibrous pericardium - outermost layer
- serous pericardium - has outer parietal and inner visceral layer with pericardial cavity (fluid filled potential space) between
15
Q
what is the inner visceral layer of the serous pericardium also known as?
A
the epicardium
it is the outermost layer of the heart
visceral layers ALWAYS covers the organ
16
Q
what is the layer under the epicardium called?
A
the myocardium - thick layer that contracts
17
Q
what are the layers of the heart (out to in)?
A
- fibrous pericardium
- serous pericardium - parietal layer
SPACE - serous pericardium - visceral layer/ epicardium
- myocardium - thick, contracts
- endocardium - inner layer of heart, endothelial cells
18
Q
how many surfaces does the heart have?
A
5
19
Q
name the surfaces of the heart
A
- anterior/sternocostal
- posterior/base
- inferior/diaphragmatic
- right pulmonary
- left pulmonary
20
Q
what is on the anterior surface of the heart?
A
- mainly right ventricle
21
Q
what is on the posterior/base surface of the heart?
A
- left atrium
- proximal great veins
22
Q
what is on the diaphragmatic/inferior surface of the heart?
A
- the left ventricle
- part of right ventricle
23
Q
what is on the left pulmonary surface of the heart?
A
- left ventricle
24
Q
what is on the right pulmonary surface of the heart?
A
- right atrium
25
what 2 margins make up the apex?
- obtuse margin (along left pulmonary)
- inferior margin (along diaphragmatic)
where they meet forms the apex
26
what are the valves of the heart? (4)
- mitrial (bicuspid) valve
- aortic semilunar valve
- pulmonary semilunar valve
- tricuspid valve
27
what and where is the fossa ovalis?
- a depression in the right atrium of the heart, at the level of the interatrial septum, the wall between right and left atrium.
- is the remnant of a thin fibrous sheet that covered the foramen ovale during fetal development.
28
what structure holds the atrioventricular valves in place?
- the chordae tendineae
| - they are held by the papillary muscles
29
what are the borders of the heart?
- the right border
- the inferior border
- the left border
- the superior border
30
what makes up the right border?
the right atrium
31
what makes up the left border?
the left ventricle (and part of left atrium)
32
what makes up the superior border
the right atrium
the left atrium
the great vessels
33
what makes up the inferior border?
the left ventricle
| the right ventricle
34
what are the sulci of the heart ?
- grooves on the surface of heart
| - created by the internal divisions of the 4 chambers
35
describe the coronary sulcus
- aka. atrioventricular groove
- runs transversely around the heart
- it represents the wall dividing the atria from the ventricles.
- contains the right coronary artery.
36
describe the the anterior and posterior interventricular sulci
- found running vertically on their respective sides of the heart.
- They represent the wall separating the ventricles.
37
what are the 2 pericardial sinuses?
1. The oblique pericardial sinus
2. The transverse pericardial sinus
The pericardial sinuses are impressions in the pericardial sac formed between the points where great vessels enter it.
38
where is the oblique pericardial sinus located?
- on posterior surface
- is a cul-de-sac
- j shaped around veins
- posterior to left atrium
39
where is the transverse pericardial sinus located?
- on superior surface
- posterior to aorta and pulmonary trunk
- anterior to SVC
40
which are the 2 main arteries supplying blood to the heart?
- the L&R coronary arteries
- these branch to supply whole heart
- arise from the left and right aortic sinuses within the aorta.
41
what are the anterior branches of the LCA?
| left coronary artery
- the left anterior descending (with diagonal branches) LAD
- the left maginal artery, LMA
- the left circumflex artery, Cx (carries on posteriorly)
42
what are the anterior branches of the RCA? describe the course
(right coronary artery)
- the right marginal artery, RMA
| - moves along the right and inferior border of the heart towards the apex
43
what are the posterior arteries of the heart?
- the left circumflex , Cx
| - the posterior interventricular artery (PIv)
44
what is the posterior interventricular artery (PIv) normally a branch of?
RMA, but can be LCA
45
how is the majority of blood drained in the heart?
- through the coronary sinus
46
where is the coronary sinus located? where does it empty?
- posterior aspect of heart
cardiac vein -> coronary sinus -> RIGHT ATRIUM
47
describe the course of the RCA
- goes right at pulmonary trunk
- runs along the coronary sulcus
- branches into RMA
- RCA carries along posteriorly, still in coronary sulcus
- then, in 90%, turns into PIv,
- follows posterior interventricular groove towards the apex of the heart
48
describe the course of the LCA
- left at pulmonary trunk
| - divides into LAD, LMA and Cx
49
describe the course of the LAD
- descends from LCA
- follows the anterior interventricular groove
- towards the apex of the heart
- continues on the posterior surface to anastomose with the posterior interventricular branch.
50
describe the course of the Cx
- follows the coronary sulcus to the left border and onto the posterior surface of the heart.
51
how are the coronary arteries supplied with blood?
when heart is relaxed, the cusps/pockets of the aortic valve/sinus fills with the back flow of blood (due to pressure drop)
52
where does the RCA supply blood to in the heart?
- right atrium
| - part of right ventricle
53
where does the RMA supply blood to in the heart?
- right ventricle
| - apex
54
where does the PIV supply blood to in the heart?
- posterior 1/3 or inter ventricular septum
| - AV node
55
where does the LAD supply blood to in the heart?
- anterior 2/3 of inter ventricular septum
- RV
- LV
56
where does the LMA supply blood to in the heart?
- left ventricle
57
where does the Cx supply blood to in the heart?
- Left atrium
| - left ventricle
58
What percentage of people have their PIV artery branch off the RCA?
70% RCA only
10% LCA only
20% RCA & LCA
therefore, for RCA = 90% (picture Venn diagram)
59
SA node supply - what % supplied by RCA or LCA?
- 60% RCA
| - 40% LCA
60
posterior intraventricular artery supplies the AV node. what proportion of people have it supplied by a PIV branching from RCA or LCA?
70% RCA only
10% LCA only
20% RCA & LCA
same q, just worded differently
61
where exactly is the apex of the heart found?
- left
- midclavicular line
- 5th intercostal space
62
why do you need to know where the apex is?
- where you can hear the mitral valve
63
what is valve auscultation?
- the action of listening to the sounds of the heart at the location of the 4 valves
64
what is the auscultation position for the aortic valve?
- 2nd intercostal space
| - right sternal border
65
when is the aortic valve heard during auscultation?
during S2
66
what is the auscultation position for the tricuspid valve?
- 5th intercostal space
| - left sternal border
67
when is the tricuspid valve heard during auscultation?
during S1
68
what is the auscultation position for the mitral valve?
- 5th intercostal space
| - mid-clavicular line
69
when is the mitral valve heard during auscultation?
during S1
70
what is the auscultation position for the pulmonary valve?
2nd intercostal space
| left sternal border
71
when is the pulmonary valve heard during auscultation?
during S2
72
which are the semilunar valves?
pulmonary + aorta
73
which are the atrioventricular valves?
tricuspid + mitral (bicuspid)
