Anatomy 1 Structure of the Heart
Objectives
- orientate the heart within the thorax
- describe the chambered structure of the heart
- describe the heart valves and the anatomy associated with heart sounds
- describe the coronary vasculature
- identify structural features of the conduction and cardiac innervation
Orienting the heart within the chest
Apex of heart
cardiac silhouette of chest radiograph
Heart is enlarged if heart is >50% of lateral distance in frontal view
mediastinum
superior pulmonary vasculature aortic arch trachea esophagus etc
inferior venacava
posterior
middle where heart lies
different places for different heart sounds are covered
we want to place the bell of stethoscope where the blood flows from for each valvular ausculatiation
Talks about pericardial sac
pericardial sinuses refers to viral pericarditis
Chambered structure of the heart
right atrium
Some land marks
sinus of venae cavae (different lineage embrogenically) from sinus venosus
fossa ovalis
coronary sinus (for shunting blood away from lungs in uetro)
valves
these areas are differentiated by the cristae terminalis
proper atrium is characterised by the presence of: (this is embrologically heart tissue)
Musculi pectinati
auricle (pig ears)
Right ventricle
tricuspid valve
- anterior
- septal
- posterior cusp
papillary muscles. usually one for each valve leaflet
chordae tendinae attach them
infundibulum/ conus arteriousis/ RV outflow tract
Pulmonary Semilunar valve
- anterior semilunar cusp
- right semilunar cusp
- left semilunar cusp
LEft artium
has the right pulmonary veins
foramen ovale and possible valve of this
mitral valve
2 cusps
trabeculae carnae
anterior and posterior papillary and anterior and posterior cusps of bicuspid valves
aortic vestibule aka LV outflow tract
Describe the heart valves and sounds associated with each
the leaflets have a nodule which enables fast snaps
lunules
histology of semilunar valves
lamina fibrosa collagen rich, tough and rigid
lamina spongiosa
Lamina ventricularis elastic rich, stretchy and snaps back
coronary vasculature
right coronary artery
left coronary arteries
- left anterior descending c art
- left circumflex artery
posterior descending artery
conduciton system
SA node
internodal pathways
AV bundle
R and L bundle bances
purkinje fibres