Anatomy of the heart lecture Flashcards
location of the heart
between the two pleural cavities
in the middle mediastinum
how is the mediastinum divided into superior and inferior
by the thoracic plane at T4/5
inferior mediastinum division
anterior
middle
posterior
what covers the heart
pericardium
layers of the pericardium
outer fibrous layer
parietal layer of serous pericardium and visceral layer of serious pericardium
fibrous pericardium
cone shaped sac surrounding the heart
fused with vessels
blended with central tendon of diaphragm
attached to the posterior surface of sternum by the sternopericardial ligaments
visceral serous pericardium
coats the heart
sometimes called epicardium
what do the two layers of serous membrane consist of
mesothelium and loose connective tissue
pariteal serous pericardium
lines internal surface of the fibrous pericardial sac
pericardial cavity
small space between the serous layers
contains pericardial fluid
pericardial sinuses
superiorly surrounding the arteries (aorta and pulmonary trunk
posteriorly surrounding veins (superior VC, inferior VC,
what are the two pericardial sinuses
transverse and oblique
transverse pericardial sinus
oblique pericardial sinus
conditions of pericardium
pericarditis
cardiac tamponade
great vessels of the heart
left and right brachiocephalic veins
inferior vena ava
pulmonary trunk
pulmonary veins
aorta
brachiocephalic veins
formed by the union of the subclavian and jugular veins
unite to form the superior vena cava
pulmonary trunk
divides into the left and right pulmonary arteries
pulmonary veins
4 of them
two left two right
aorta
arch
brachiocephalic trunk
common carotid (left)
subclavian (left)
what separates the right atrium
the crest terminalis
which is a thick muscular ridge
what are the walls anterior to the crista terminalis covered in
muscular ridges called muscle pectinati
pectinate muscles
walls posterior to the crista terminalis
smooth
what is the fossa ovalis
mark the location of the embryonic foramen ovale
where does deoxygenated blood enter the right atrium
SVC IVC or coronary sinus
irregular muscular ridges
trabeculae carneae
what does tricuspid have
three cusps
what is each cusp attach to
chordae tendineae
what do chordae tendineae attach to
two papillary muscles
what does the pulmonary semilunar valve consist of
semilunar cusps
right atrium internal features
2 structures separated by crista terminalis
walls anterior covered in pectinate muscles
walls posterior are smooth
fossa ovalis mark location of embryonic foramen oval
dexoxygenated enters via SVC, IVC, coronary sinus
what is in the image
right atrium
internal features of the right ventricle
trabeculae carneae
tricuspid valves, each cusp attached to chordae tendineae
attached to two papillary muscles
deoxygenated leaves via pulmonary trunk
what is in the image
right ventricle
what is the left atrium derived from
posterior half with smooth internal walls
anterior half contains musculi pectinati and is continuous with the left auricle
internal features of the left atrium
posterior and anterior
valves of foramen ovale
valve of foramen ovale
important developmentally
not always completely fused in adults
posterior half of left atrium
receives the 4 pulmonary veins
what is in the image
left ventricle
internal features of the left ventricle
mitral/bicuspid valve with two cusps
cusps attach to the papillary muscles via chordae tendineae
trabeculae carneae present
longer and thicker walls (myocardium) than right ventricle
aortic semilunar valve has 3 cusps
oxygenated out by aorta
surfaces of the heart
sternocostal (anterior)
diaphragmatic (inferior)
base (posterior)
left and right pulmonary
borders of the heart
right
inferior
left
superior
surface marking of the aortic valve
medial end of the right 2nd intercostal space
surface marking of the pulmonary valve
medial end of the left second intercostal space
surface marking of the tricuspid valve
left of the lower part of the sternum
near the 5th intercostal space
surface marking of the bicuspid valve
left 5th intercostal space at the midclavicular line
process of electrical conduction
Sino-atrial node (cardiac pacemaker) generates excitatory signals.
* Excitatory signals spread across the atria causing them to contract.
* The wave of excitation stimulates the atrioventricular node.
* Signal travels down the atrioventricular bundle.
* The bundle is specialist tissue which conducts the excitatory impulse to all ventricle musculature.
The atrioventricular bundle divides in to a left and
right branch.
* The branches descend towards the apex
* Further divide into terminal pukinje fibres.
* The wave of excitation causes the ventricles to
contract from the apex upwards.
* The Autonomic division of the PNS is directly
responsible for controlling heart rate and the force
of contraction
fibrous cardiac skeleton
4 interconnected rings of dense fibrous connective tissue surrounding the two AV orifices (aortic and pulmonary valve)
maintains integrity of openings it surrounds
provides cusps attachment
provides solid structure for muscle to contract against
separated atrial musculature from ventricular musculature
electrically isolated
electrical isolation
The fibrous skeleton separates
the atrial half of the heart from
the ventricle half of the heart.
They are electrically isolated
* The Atrioventricular bundle passes
through the skeleton and is the
only connection between the two
groups of myocardium (cardiac
tissue).
coronary arteries
right, arises form the right aortic sinus
left, arises from the left aortic sinus
