CVS anatomy Flashcards
what is the cardiovascular system
heart - pump
blood vessels
lymphatics
what are the functions of the 3 types of blood vessesl
arteries - distribute blood away from heart
capillaries - exchange nutrients
veins - collect and return blood to the heart
what is the function of the lymphatics
drain XS extracellular fluid from tissues
what happens if XS fluid builds up in tissues
oedema
where is the CVS located
heart - middle mediastinum
blood vessels - everywhere except cartilage
lymphatics - everywhere except brain and eyes
what is the mediastinum
block of structures standing in between the 2 pleural cavities
where is the superior mediastinum located
above the sternal angle up to the first rib
where is the inferior mediastinum located
below the sternal angle down to the diaphragm
what is the inferior mediastinum split up into
anterior, middle and posterior mediastinum
what is located in the middle mediastinum
the heart
this is the biggest mediastinum
describe the anterior mediastinum
it is small
thin cleft between the pericardium and the sternum
contains fat, fibrous tissue and sternal pericardial ligament
what is located in the posterior mediastinum
aorta, oesophagus, sympathetic chains
what are the 2 main circulations
pulmonary: heart, lungs, heart
systemic: heart, body, heart
what are the other types of circulation apart from the 2 main ones
portal systems: hepatic portal circulation
lymphatic system
what are portal systems
seen in the liver, pituitary and hypothalamus
set of veins that being in the vein, break up into capillaries and ends up in veins again
how is the heart orientated
faces slightly to the left and downwards
what are the great vessels of the heart
L and R pulmonary veins (enter the L atrium posteriorly)
superior and inferior vena cava
R and L pulmonary artery (join to form the pulmonary trunk)
aorta - ascending, aortic arch, descenfing
where is the aortic arch loctaed
T4
what chamber forms the apex of the heart
L ventricle
which chamber forms the base of the heart
L atrium
sits posteriorly
lies in front of the oesophagus
which vessels enter the R atrium
superior and inferior vena cava
which vessels leave the R ventricle
L and R pulmonary artery
which vessels enter the L atrium
L and R pulmonary veins
which vessels leave the L ventricle
aorta
what is the thymus gland
dissipates at puberty
fibrous fatty mass remains that lies in the anterior mediastinum
where does the heart lie in recumbent position
vertebra T5-T8 (middle 4 T vertebrae)
where is the apex of the heart located
5th L intercostal space in the midclavicular line
some references say 4th IC space
where is the LA located
wholly posterior
lies in front of the oesophagus
why does the heart move up and down
as you breath - attached to the diaphragm
gravity - drops slightly as you stand up (T6-9)
what is the position of the heart in children
higher up and lies more horizontal
what is situs inversus
dextrocardia
heart has swung to R side of chest rather than L
anterior anatomical relations of the heart
sternum and costal cartilages 4-7
anterior edges of the lungs and pleura - cover the front of the heart
thymic remnants
posterior anatomical relations of the heart
oesophagus
descening aorta
thoracic vertebrae 5-8
lateral anatomical relations of the heart
lungs
phrenic nerve
inferior anatomical relations of the heart
central tendon of diaphragm
heart sits on and is attached to the central tendon
what are the 3 layers of the heart wall
endocardium - innermost
myocardium
epicardium - outermost
describe the endocardium
lines heart chambers
single layer of simple squamous epithelium (endothelium) sitting on BM and connective tissue
forms valves
describe the myocardium
thick middle layer of heart wall
cardiac muscle
branching fibres w/ single central nu, myocytes connected by intercalated discs
many mitochondria
rich capillary bed
muscle bundles in different planes to close down chamber lumen
describe the epicardium
outer layer of heart wall
simple squamous epithelium lying on BM with a thin layer of connective tissue underneath
contains main branches of coronary arteries
may be fatty
what is epicardium epithelium also known as
visceral layer of serous pericardium
descibe all the layers of the heart from inner to outer
endocardium myocardium epicardium (visceral layer of serous pericardium) pericardial cavity parietal layer of serous pericardium fibrous pericardium
what is the fibrous pericardium
layer around the visceral and parietal pericardium, protective function (dense, connective tissue)
what is the function of the coronary arteries
supply the tissue of the heart with oxygenated blood
what are the 4 chambers of the heart
R and L atrium
R and L ventricle
how is the direction of blood flow in the heart controlled
valves
what is carried in the vena cava
deoxy blood from body
what is carried in the pulmonary artery
deoxy blood to lungs
what is carried in the pulmonary vein
oxy blood from lungs
what is carried in the aorta
oxy blood to rest of body
what forms the R boreder of the heart
R atrium (mainly)
what forms the inferior border of the heart
R and L ventricle
what forms the L border of the heart
L ventricle
what forms the superior border of the heart
the great vessels
define cusps
thin structures derived from endocardium
do herat valves work actively or passively
passively
what 2 structures prevent valve failure and how
chordae tendineae
papillary muscles
prevent the valves inverting
why are heart valves clinically important
abnormalities - incompetence (widening, blood flows out and leaks back)
stenosis (narrowing, blood can’t get through)
infection - bacterial endocarditis, valve can be destroyed
what are the 4 heart valves
pulmonary valve
aortic valve
mitral valve
tricuspid valve
which valves are semilunar valves
aortic and pulmonary
each have 3 cusps
which type of valve is the L AV valve
mitral valve
bicuspid
what type of valve is the R AV valve
tricuspid
what is the fibrous cardiac skeleton composed of
dense connective tissue
where does the fibrous cardiac skeleton lie
in the plane between the atria and ventricles
this plane corresponds to AV groove/orifices of the heart
what is the role of the fibrous cardiac skeleton
structural support - AV septum, roots of great vessels, anchorage for valves, myocytes/capillary network
electrical insulation - atria from ventricles, myocardium from great vessels
how does blood enter the coronary arteries during systole and diastole
systole - openings in aortic sinuses shielde by aortic valve cusps
diastole - elastic recoil of aorta closes aortic valve and blood enters arteries, myocardium relaxes and blood can flow into capillaries
where are the coronary arteries located
in the epicardium
what holds the heart in place
hangs by great vessels within fibrous pericardium
dense connective tissue bag
attachments - central tendon of diaphragm, sternum, roots of great vessels
lined by serous pericardium
heart free to move
describe the serous pericardium
epithelium
secretes pericardial fluid - lubricant
visceral and parietal layer
allows freedom of movement during cardiac cycle
what are the visceral and parietal layers of the pericardium bound to
visceral - heart
parietal - fibrous pericaridum
visceral and parietal layers are continuous and form a closed bag
