Cardiovascular system - Weeks 3&4 Flashcards
(lateral view of mediastinum) A horizontal plane drawn between which two bone structures separates the mediastinum into superior and inferior parts?
between sternal angle of sternum and T4/T5 vertebrae
what can the lower/inferior mediastinum be further divided into?
anterior, middle and posterior
name the structures found in the superior mediastinum
oesophagus, trachea, aortic arch, superior vena cava, L/R phrenic nerves, L/R vagus nerves, thoracic duct, sympathetic chains
name the structures found in the anterior (front) section of the inferior mediastinum?
thymus and fat
name the structures found in the middle part of the inferior mediastinum
heart, L/R phrenic and vagus nerves, cardiac plexus
name the structures found in the posterior part of the inferior mediastinum
descending aorta, oesophagus, thoracic duct, azygos vein, sympathetic chain
what does the azygous system of veins drain?
the posterior thoracic wall
what is the name of the structure which returns lymph to the venous system?
thoracic duct
what are the roots of the phrenic nerve? (…. ….. ….. , keep….. alive)
C3,4,5
(lateral view of torso) Which nerves lie anterior to the root of the lung?
which lie posterior?
anterior = phrenic
posterior = vagus
what is the name of the sac which lies around the heart?
pericardium
name the 2 layers of the pericardium - outer and inner
outer = fibrous pericardium
inner = serous pericardium
the inner serous pericardium has 2 layers, name them (inner and outer)
inner serous = visceral/epicardium (external layer of the heart)
outer serous = parietal
going from outermost to innermost, name the layers of the pericardium
fibrous pericardium, parietal serous pericardium, visceral serous pericardium (epicardium)
which layer of the pericardium is just the external surface of the heart?
epicardium (inner serous layer)
name the 4 functions of the pericardium
protection from infection
fixes heart in mediastinum
lubrication
prevents heart overfilling and thus increasing in size
what is the function of the fluid which fills the pericardial cavity? which two layers of pericardium does cavity form between?
reduce friction when heart is contracting
forms between the inner and outer serous (epicardium and parietal)
which structures does the pericardium fix the heart to in the mediastinum?
tunica adventitia of blood vessel walls, diaphragm, sternum
in cardiac tamponade where does fluid accumulate?
in the pericardium
cardiac tamponade can result from what?
heart surgery, bacterial/viral infection, trauma, heart attack
in cardiac tamponade, what fills up the pericardium, compressing the heart? (2 things)
blood or fluid
what does fluid/blood build up in the pericardium prevent in cardiac tamponade, which in turn causes a build up of pressure in the heart?
prevents ventricles from expanding fully, impeding blood supply
define pericarditis
inflammation of the pericardium
name the procedure done to remove fluid that has built up in the pericardium in cardiac tamponade?
pericardiocentesis
when looking at the heat in a posterior view, which 7vessels would you see (from top downwards)? what would you see on the RHS - 1 vessel?
aortic arch coming over top
left and right pulmonary arteries below aortic arch
2 left and 2 right pulmonary veins (superior set and inferior set)
on RHS = vena cava
name the 5 surfaces of the heart
anterior, base, diaphragmatic, left pulmonary, right pulmonary
in the midclavicular line, the apex of the heart lies posterior to which intercostal space?
5th
which border of the heart covers both atria and has the aorta and pulmonary trunk arising from it?
superior
which border of the heart extends from the superior vena cava to inferior vena cava and is formed by the right atrium?
right border
which border of the heart is formed by the right ventricle mostly, with a small contribution from the left ventricle?
inferior
which border of the heart is formed by the left ventricle with the superior portion being formed by the left auricle?
left
which structures lie at the level of the sternal angle?
aortic arch, bifurcation of trachea, rib 2, pulmonary trunk, nerves
Select the answer that best describes the direction of the apex of the heart:
- Latero-inferiorly, sideways and down
- Postero-superiorly, backwards and up
- Antero-inferiorly, forwards and down
- Postero-inferiorly, forwards and down
antero-inferiorly, forwards and down
the base of the heart is located on its……. aspect, facing towards the bodies of vertebrae T6-………..
posterior
T6-9
the anterior surface of the heart is formed mainly from the ……….. ventricle and related anteriorly to the sternum and ribs
right
The ………. surface is formed mostly from the left ventricle and is related inferiorly to the centre of the diaphragm.
inferior
name the 3 layers which make up the walls of the heart from superficial to deep?
epicardium
myocardium
endocardium
which layer of the heart wall is the same as the visceral pericardium?
epicardium
which layer of the heart wall provides a protective layer over the heart and is composed of connective tissue?
epicardium
which layer of the heart wall is the muscle layer? what is the name of the cell types found here?
myocardium, myocytes/cardiac muscle cells
which layer of the heart wall is a layer of connective tissue covering the valves, continuous with the endothelial lining of blood vessels?
endocardium
true or false, an electrical stimulus to any one part of the heart can cause contraction of the whole myocardium? explain your answer
true as cardiac muscle cells are branched and interconnected = operate as a functional syncytium
intercalated discs separate adjacent cardiac muscle cells. what are the discs held together by (type of junction)?
desmosomes
intercalated discs are held together by……. and allow electrical excitation to pass between cells through ……….. junctions?
desmosomes, gap junctions
the fibrous skeleton of the heart consists mainly of what?
collagen
name the 3 functions of the heart’s fibrous skeleton
1 - prevents valves collapsing
2- base for attachment for valve cusps
3 - forms electrical barrier between atria and ventricles to stop them contracting together (septum)
which structure, composed of dense collagen, forms an electrical barrier between the atria and ventricles, preventing them from contracting together?
fibrous skeleton of the heart
the AV bundle ensures which chambers contract first? it also ensure the ventricles contract from the …… upwards?
atria first
apex upwards
cardiac muscle is …….. (appearance) and not under…… control
striated, not under conscious control
do cardiac and skeletal muscle both contract by a sliding filament mechanism?
yes
true or false, skeletal muscle cells are less linear than cardiac muscle cells?
false, they are more linear
between which two chambers of the heart is the mitral/bicuspid valve found?
left atrium and left ventricle
between which two chambers of the heart is the tricuspid valve found?
right atrium and right ventricle
in which atrium, or atria, is this structure found?
crista terminalis
right atrium only
in which atrium, or atria, is this structure found?
fossa ovalis
both atria
name the main cardiac vein where the deoxygenated blood drained from the heart itself returns to the heart’s circulation?
around which atrium would you find the coronary sinus?
coronary sinus - right atrium
in which atrium, or atria, is this structure found?
pectinate muscles
both atria
in which atrium, or atria, is this structure found?
SA node
right atrium
in which atrium, or atria, is this structure found?
sulcus terminalis
right atrium only
what is the name of the structure in the right atrium where the pectinate muscles originate from?
crista terminalis
at the interatrial septum, which 2 structures would you find?
fossa ovalis and AV node
what is the function of the right and left auricles?
to increase the capacity of the atria
which structure marks the point of fusion between the venous part of the right atrium and the true right atrium?
what structure sits on the internal surface of this structure?
sulcus terminalis
crista terminalis
in which atrium are the pectinate muscles more sparse?
left atrium
in which ventricle, or ventricleS, is this structure found?
tricuspid valve
right ventricle
in which ventricle, or ventricleS, is this structure found?
chordae tendinae
both
in which ventricle, or ventricleS, is this structure found?
conus arteriosus
right ventricle
in which ventricle, or ventricleS, is this structure found?
moderator band
right ventricle
in which ventricle, or ventricleS, is this structure found?
papillary muscles
both right and left
in which ventricle, or ventricleS, is this structure found?
traberculae carneae
both ventricles
in which ventricle, or ventricleS, is this structure found?
mitral valve
left ventricle
which two structures do the chordae tendineae attach to in the ventricles?
cusps of atrioventricular valves and papillary muscles of ventricle
name the anterosuperior region of the right ventricle
which vessel arises from this region?
conus arteriosus, pulmonary trunk
where does the moderator band begin and end (2 structures) in the right ventricle?
intraventricular septum and right anterior papillary muscle
what does the moderator band act as a shortcut for in the right ventricle?
acts as a shortcut for electrical impulses from right bundle tract
when papillary muscles contract in the ventricles, what do they pull on to prevent prolapse of the atrioventricular valve cusps?
chordae tendineae - heart strings
in the right ventricle, name the 3 locations of papillary muscles
anterior, posterior and septal
which structure is this describing? irregular muscular columns found on the internal surface of the ventricles (meaty ridges)
trabeculae carneae
on a cadaveric image/diagram of the right ventricle, which structure looks like a papillary muscle but isn’t because it isn’t connected to any heart strings (chordae tendineae)?
moderator band
semilunar valves are between …….. and ……..
vessels and ventricles
lub sound is caused by closure of …….. valves
atrioventricular
dub sound is caused by closure of …….. valves
semilunar
what happens to ventricular pressure when atrioventricular valves close?
increases (lub)
what happens to ventricular pressure when semilunar valves close?
decreases (dub)
going from the right hand heart chambers to the left, which atrioventricular valves comes first - tri or bi cuspid?
tricuspid first - right AV valve
how many cusps in semilunar valves? what is the name of the spaces behind the aortic semilunar valve?
3
aortic sinuses
which two valves are prevented from inverting by the action of the
papillary muscles and chordae tendineae
tri and bicuspid
At the beginning of diastole blood begins to flow ……….. the heart; this fills the ‘pockets’ (known as sinuses) and forces them together, ………….. the valve. (aortic and pulmonary valves)
towards, closing
the QRS signal on an ECG represents depolarisation of what?
ventricles
write the correct order
1) purkinje fibres spread impulse throughout ventricular myocardium causing contraction
2) AV node receives the impulse from the SA node
3) left and right bundle branches transmit APs from bundle of His to Purkinje fibres
4) SA node spontaneously depolarises
5) bundle of his transmits signal down interventricular septum - it splits into 2
6) conduction to AV node via internodal tracts
4, 6, 2, 5, 3, 1
from the AV node, where does the impulse travel through next?
after this, what happens so that the impulse is transmitted to whole myocardium?
through bundle of his
bundle bifurcates into left and right, purkinje fibres spread impulse through entire myocardium
which arteries help supply blood to the heart so that it can keep beating constantly?
coronary arteries
what do the coronary arteries arise immediately superior to?
cusps of aortic valve from aortic sinuses
name the 3 aortic sinuses
posterior, right and left
from which aortic sinus is there no coronary artery arising from?
posterior
name the branches of the left coronary artery
anterior interventricular, circumflex
which direction does the anterior interventricular branch of the LCA travel in? towards what? what does it supply the walls of?
travels down anterior surface of heart towards apex, supplying anterior walls of both ventricles
which groove does the circumflex branch of the LCA travel down? which artery does this branch also give off?
coronary/atrioventricular groove down left border
left marginal artery
in most people, which coronary artery usually supplies the SA node?
right
close to its origin, the RCA gives off an ascending branch called what?
SA node branch
name the 3 branches of the RCA
sinoatrial, marginal and posterior interventricular
which branch of the RCA forms an arterial ring around the superior vena cava?
sinoatrial branch
A network of cardiac veins drains deoxygenated blood from the heart tissue and deposits it in the …….. This drains directly into the ……… atrium. coronary sinus is located on …….. side of heart
coronary sinus
right atrium
posterior
which is the most common artery for myocardial infarction?
left anterior descending
when does myocardial infarction occur?
when a coronary artery gets blocked and the myocardium becomes ischaemic (tissue death due to lack of oxygen)
name the two treatments used for heart attacks
PCI - widen blocked vessel with a stent - access it through artery in groin
thrombolytic drugs
coronary artery bypass graft
name the three layers of blood vessels starting with the innermost to outermost
innermost = tunica intima
middle = tunica media
outermost = tunica adventitia
which layer of blood vessels is the smooth muscle layer, containing elastin and collagen?
middle - tunica media
what is the name of the small blood vessel network that is responsible for nourishing the media, contained within the adventitia?
vasa vasorum
the blood pressure created by the elastic recoil of arteries (following expansion) is known as what?
diastolic blood pressure
which type of artery, conduit (muscular) or elastic, has a thicker tunica media relative to the lumen of the vessel? why?
conduit - more smooth muscle to prevent collapse
conduit arteries can contract and relax so they are highly innervated by what?
autonomic nervous system - can contract or relax
name 3 elastic arteries
aorta, pulmonary artery, iliac
name 3 conduit arteries
radial, cerebral, coronary
in which vessel does blood travel at its lowest pressure and slowest speed?
capillaries
name the 3 types of capillary (think basement membrane)
continuous, fenestrated, sinusoid
name 2 tissue types in which ateriovenous anastomosis are found. what are their functions in these 2 tissues?
skin and nasal mucosa
in nasal mucosa - warm inspired air
in skin - temp regulation
in limbs, what is special about the tunica intima layer of veins, as opposed to arteries?
has valves
what are the 3 branches off the aortic arch
brachiocephalic trunk (right subclavian and right common carotid), left common carotid, left subclavian
at which vertebral level do the carotid arteries divide into internal and external?
C3-C4
which branch of the carotid supplies the brain?
internal
which branch of the carotid supplies the neck, face, scalp on its respective side?
external
the subclavian artery first becomes the ….. and then the …… artery in the upper limb
axillary, then brachial
at which vertebral level does the abdo aorta pass through the aortic hiatus of diaphragm?
T12
from most superior to inferior name the branches of the abdominal aorta which supply abdomen, pelvis and lower limb, including where it bifurcates at the pelvis
superior: coeliac trunk, superior mesenteric, renal arteries, inferior mesenteric, right and left common iliac
name the organs which the coeliac trunk supplies
stomach, liver, gallbladder, spleen, pancreas
name the structures which the superior mesenteric artery supplies
midgut structures of the abdomen including most of the small intestine and the proximal portion of the large intestine
what structures does the internal iliac artery supply on each side?
pelvic cavity and perineum
what does the external iliac artery continue as on each leg?
femoral artery
at what vertebral levels are the superior mesenteric, renal, inferior mesenteric arteries? which level is the bifurcation of the iliac artery?
SM = L1
R = L1/L2
IM = L3
I = T4
veins drain into other veins, so they have…….. not branches
tributaries
which vein drains most of the head and neck?
internal jugular
which vein drains upper limb?
subclavian
on each side of the body in the head/neck the ………. vein and …….. veins join together to form a ………. vein. These join togetjer to form the superior vena cava
internal jugular and subclavian join to form brachiocephalic veins
what are the 3 main tributaries of the inferior vena cava
renal, lumbar and hepatic
what is the name of the vein which drains the posterior thoracic wall as well as draining into the superior vena cava
azygous vein
the portal venous system (a collection of veins) drains into the ….. before draining into the …… and back the the heart
liver
inferior vena cava (and hepatic veins)
order these vessels from smallest to largest diameter
- arteries
- arterioles
- capillaries
- atriovenous anastomosis
- venules
- veins
smallest: capillaries
ateriovenous anastomosis
venules
arterioles
arteries
veins
