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