CVS anatomy Flashcards
where does the heart lie
in the middle mediastinum
what is the heart next to anteriorly
Sternum & costal cartilages 4-7
what is the heart next to posteriorly
Oesophagus & Descending aorta
what is the heart next to laterally
Pleura & Phrenic nn.
what is the heart next to inferiorly
Central tendon of diaphragm
what vertebrae does the heart lie anteriorly to
T5-T8
where is the apex of the heart
5th left ic space, midclavicular line
what is the right border of heart
RA
what is the left border of heart
LV
what is the superior border of heart
auricles and great vessels
what is the inferior border of heart
RA, RV + LV
what is the sternocostal (anterior) surface of heart
1/3 RA, 2/3 RV + LV
what is the diaphragmatic (inferiro) surface of heart
RV + LV
what is the posterior surface of heart (base)
LA
what rib is the left superior part of the heart at
rib 2
what rib is the right superior part of the heart at
rib 3
what rib is the right inferior part of the heart at
rib 6
what rib is the left inferior part of the heart at
rib 5
what is the pericardium
what are the 2 layers
covers the heart
fibrous
serous
what is the fibrous pericardium
dense connective tissue sac
what is the serous pericardium
Outer parietal layer
Inner visceral layer = Epicardium
pericardial cavity filled w fluid
what are the 2 main coronary arteries
right and left CA
where does RCoronary artery arise from and where does it run
r. aortic sinus of asc. aorta
runs in in coronary (atrioventricular) sulcus
where does LCoronary artery arise from and where does it run
Arises from l. aortic sinus of asc. aorta
Runs in coronary sulcus
what does RCA branch off into
At inferior margin of heart it gives off r. marginal a.
post. interventricualr a.
what does LCA branch off into
circumflex a.
l. ant. interventricular a.
what are the 2 anatomoses on the heart (junction of vessels)
Ant + Post descending
Circumflex + RCA
on post surface
what are the 2 major sulci
Coronary (Atrioventricular) sulcus - between atria + ventricles
Interventricular sulcus - between r + l ventricles
what does the right coronary artery supply
RA and RV
what does right marginal artery supply
RV and apex
what does left marginal artery supply
LV
what does left anterior descending artery supply
RV LV and interventricular septum
what are the 3 main veins of the heart wall and where do they drain
Great cardiac vein lies alongside
ant interventricular a.
Middle cardiac vein lies alongside post interventricular a.
Small cardiac vein lies alongside r. marginal a.
drain into coronary sinus lying alongside circumflex - drain into RA
where do the anterior cardiac veins drain
directly into RA
what is the hearts rate of contraction set by
pacemakers cells found in the SA node
what innervates the heart
autonomic NS
what innervates fibrous pericardium + parietal layer of serous
Phrenic nerve
carries pain sensation
what innervates heart and visceral layer of serous pericardium
Vagus nerve (parasympathetic
what sympathetic nerves innervate heart + visceral layer
T1-4 ganglia
where does the aortic arch end
T4 vertebrae
what controls the direction of blood flow in heart
valves
what opening are there in RA
IVC, SVC, Coronary sinus
what valve is between RA and RV
Tricuspid valve
what is attached to tricuspid valve in RV
Tricuspid valve
3 valve cusps
Chordae tendineae
Papillary muscles x3
what are trabeculae carneae and where r they
contractile fleshy struts
on anterior inner wall in RV and LV
what openings does LA have
l + r superior pulmonary veins
l + r inferior pulmonary veins
what valve between LA and LV
Bicuspid (mitral) valve
what does left atrium lie against posteriorly
lying wholly postero-superiorly against oesophagus.
how much thicker is the wall of LV to the RV
Wall 3x as thick as right ventricular wall.
what is the pathway of intrinsic innervation in the heart
signals in SA node -> AV node -> bundle of His -> Purkinje fibres -> endocardium at apex -> ventricles -> epicardium
where is the aortic valve
right 2nd ICS
where do you auscultate pulmonary valve
left 2nd ICS
where is mitral valve aucultated
left 5th ICS at midclavicular line
where is tricuspid valve
left 5th ICS next to sternum
what are the main vessels of anterior chest wall
Internal Thoracic a.
Gives off anterior intercostal arteries
Internal Thoracic v.
Receives anterior thoracic veins
what are the main vessels of posterior chest wall and trunk
IVC and SVC
descending aorta
azygous vein, drain posterior Intercostal veins into SVC
thoracic and right lymphatic duct
where does subclavian artery arise from
Subclavian arises from aortic arch
what are the main arteries of upper limb, in order
subclavian artery axillary artery brachial artery radial (thumb side) and ulnar digital a. in palm
what are the superficial veins of upper limb
cephalic vein - lateral side
basilic - medial
median cubital vein connects them across cubital fossa
what are the main arteries of lower limb, in order
Ext. iliac becomes common femoral in ant. thigh
superficial and deep femoral
superficial -> popliteal in popliteal fossa
-> anterior and post tibial in leg
ant tibial -> dorsalis pedis between 1st & 2nd toes
post tibial -> fibular artery to plantar of foot
where do superficial veins arise from in the upper limb
from the dorsal venous arch on the back of the hand
where does common femoral a in leg come from
external iliac
what are the superficial veins of lower limb
veins arise from dorsal arch of foot
long saphenous travels up medially to drain into femoral
short saphenous travels up posteriorly into popliteal
what are the main arterial pulse points
carotid brachial radial femoral popliteal post. tibial dorsalis pedis
what are the 3 layers of the heart
Epicardium - outer layer.
Myocardium
Endocardium
what are the layers of the heart wall
endocardium, myocardium, epicardium
what is the t.media made up of
muscle and elastic tissue
what is the t.intima made up of
epithelium, bm, connective tissue
what is the t.adventita made up of
fibrous connective tissue
what does the endocardium form
valves
what epithelium type is the endocardium
simple squamous
what are the features of the myocardium
thick, myocytes, striated muscle, muscle bundles in dif planes to close down chamber lumen, myocytes connected by intercalated discs
what is the epicardium
Outer layer of heart wall
Epithelium = visceral layer of serous pericardium
what are the features of arteries
thick muscle wall,
smaller, rounded
thin adventitia
what are the features of veins
- thin muscle wall
- large flattened
- thick adventitia
- valves to prevent back flow
what are the types of arteries
Elastic - large conducting, aorta
Muscular - distributing, coronary arteries
Arterioles - terminal branches, supply capillaries
describe elastic arteries
pressure revoir
Stretched during systole
Elastic fibres in t.media in form of layers = laminae
Purple bits are elastic laminae
elastic fibres secreted by the smooth muscle cells
describe muscular arteries
thick t.media has smooth muscle cells
No elastic laminae between muscle cells in media
Elastic fibres in 2 sheets, internal elastic lamina under epithelium and external elastic lamina between t media and adventitia
describe arterioles
1-2 layers of smooth muscle in t.media
No adventitia
Rich sympathetic nerve innervation
describe capillaries
v thin t.intima, no other layers
Pericytes - incomplete layers of cells, have contractile properties to control blood flow
Pressure is low
what are pericytes
on capillaries
incomplete layers of cells, have contractile properties to control blood flow
what are the 3 types of capillaries
continuous, fenestrated, sinusoids
what are continuous capillaries
control what is exchanged
Selective transport mechanisms
e.g. in muscle
no clefts or pores
what are fenestrated capillaries
has pores
Diaphragms filter molecules by MW or charge
Endocrine glands or kidney
what are discontinuous capillaries
gaps between endothelial cells
Allow free passage of fluid and cells
liver, spleen, bm
what are atriovenous shunts
bypass capillary beds
Arteriole -> venule
what are sinusoids
Large diameter discontinuous capillaries
Found where large amount of exchange takes place
T. intima contains phagocytic cells
all 3 layers thin of veins and venules
ff
what forms valves in veins
folds of t. intima
describe superficial veins
thick walls
No surrounding support
describe deep veins
thin walled
Support from deep fascia and muscles
Superficial drain into deep veins
where are lymphatic nodes found
Nodes found alongside major veins and around origins of major arteries
describe lymph capillaries
blind ended
Lined by v thin endothelium
Anchoring filaments - fine collagenous filaments link endothelial cell to surrounding tissue to keep lumen open
no rbc in lumen
how are blood vessels organs
recieve own nerve supply, symp and parasymp
- blood supply, vasa vasorum
- lymphatics in T.adventita
what are the 5 main stages of development for heart in the embryo
bilateral heart primordial Primitive heart tube Heart looping Atrial and ventricular septation Outflow tract septation
when does cvs start functioning in embryo
in 4th week
where do blood vessels first appear
first appear in the yolk sac, allantois, connecting stalk and chorion
called the cardiogenic field
what forms the two heart tubes
blood vessels in lateral plate splanchnic mesoderm form two heart tubes
how is primordial cardiovascular system formed
Heart tubes fuse and join blood vessels in other areas
why is heart tube dorsal to pericardial cavity
cranial folding of embryo heart tube comes to lie dorsal to pericardial cavity
what does the pericardial cavity form from
from intra-embryonic coelom
what are the areas of the fused primitive heart tube
truncus arteriosus bulbus cordis primitive ventricle primitive atrium sinus venosus
what does primitive heart tube invaginate
pericardium
whats it called when heart tube becomes too large for pericardium so needs to loop
bulboventricular loop
what happens when the heart loops
Bulbs cordis and ventricle looped to the right
Ventricle pushed left and inferiorly
Atria pushed superiorly and posteriorly
what is dextrocardia
heart loops to left
how are left and right atrioventricular canals formed
Endocardial cushion growth in the middle
how are right and left atria formed
Septum premium grows down, osmium primum grows up. Ostium secondum forms and septum secondum.
closure of ostium primum as septum primum meets endocardial cushions
foramen ovale - gap between RA and LA
whats the purpose of foramen ovale
shunt blood from right atrium to left
how is foramen ovale closed
Septum primum fuses with septum secundum
Fossa ovalis in adults
how are primitive ventricles partitioned
Muscular ventricular septum forms. Opening is called interventricular foramen.
Bottom of spiral aorticopulmonary septum fuses with muscular ventricular septum and endocardial cushions to form membranous interventricular septum, closing interventricular foramen.
what does aorticopulmonary septum do
divides bulbis cordis and truncus arteriosus into aorta and pulmonary trunk
spirals
whats Ventricular Septal Defect (VSD)
hole in interventricular septum
what is the Transposition of great vessels
two main blood vessels leaving the heart, the pulmonary artery and the aorta are swapped over
what can cause Transposition of great vessels
Failure of aorticopulmonary septum to take a spiral course
- 2) Defective migration of neural crest cells to heart
how are atrioventricular valves formed
develop from the ventricular wall
what are semilunar valves formed from
subendocardial valve tissue
explain development of conducting system in heart
Early pacemakers are cardiomyocytes in primitive atrium and sinus venosus
SA node develops during 5th week, in RA high
AV node and bundle develops from cells of AV canal and sinus venosus
what are the First arteries to appear in the embryo
right and left primitive aortae
have ventral and dorsal bit
how is aortic sac formed
from fusion of the 2 ventral aortae
aortic sac then becomes an extension of truncus arteriosus
where does aortic arch branches arise from
Aortic arch arise from aortic sac in 4th and 5th week
how many branches of aortic arches are there and what do they unite with
6 pairs of aortic arches, unite w dorsal aortae
what is vasculogenesis
new formation of primitive vascular network
what is angiogenesis
growth of new vessels from pre-existing blood vessels
what are the adult derivates of the aortic arches
1 + 2 + 5 disappear
3 - carotid artery
4 - right subclavian vein
Left - aortic arch
6 - r+l pulmonary arteries and ductus arteriosus
what does 3rd aortic arch become
forms the common carotid artery
what does 4th aortic arch become
right archforms theright subclavian artery
The 4th left arch forms the aortic arch
how does a double aortic arch abnormality form
non-regression of the right aortic arch (4th) forming a vascular ring around the trachea and oesophagus, which usually causes difficulty in breathing and swallowing.
what is patent ductus arteriosus
ductus arteriosus fails to close after birth
oxygenated blood from the left heart to flow back to the lungs by flowing from the aorta to the pulmonary artery.
failure of muscular wall to contract
what is coarctation if the artery
constriction of aorta
aortais narrow
what does Vitelline vessels supply and what does it become in adult
supply yolk sac
adult gut vessels
what does Umbilical vessels supply and what does it become in adult
supply placenta
internal iliac
what does Cardinal vessels supply and what does it become in adult
supply rest of body
SVC & IVC
when does lymphatic system develop
end of 6th week
Six primary lymph sacs develops
ThoracicDuctdevelopsfrom two vessels anterior to the aorta
how does foetal IVC receive oxygenated blood from placenta
via umbilical vein
what are the 3 foetal circulation shunts
Ductus venosus - shunts blood from left umbilical v -> IFC
Foramen ovale - ra -> la
Ductus arteriosus - rv + pulm a -> aorta
what is the ductus venosus shunt
shunts blood from left umbilical v -> IFC
oxygenated blood from the placenta to bypass the liver.
what is the Foramen ovale shunt
ra -> la
what is the Ductus arteriosusshunt
rv + pulm a -> aorta
blood bypass lungs
what does ductus venosus become after birth
ligamentum venosum of the liver
what does ductus arteriosus become after birth
ligamentum arteriosum between left pulmonary artery and aorta
what do umbilical arteries become after birth
medial umbilical ligaments of the anterior abdominal wall
