UNIT 2: heart Flashcards
where is the heart located?
middle mediastinum - behind sternum/ between 2nd and 6th ribs and between T5-8/ directly above diaphragm
where can you find the apex of the heart?
posterior to 5th intercostal space- left midclavicular line
where is the base of the heart?
posterior towards T6 to T9 (predominantly left atrium)
What are the four surfaces of the heart?
- anterior/ sternocostal - RV
- diaphragmatic/ inferior - LV
- left pulmonary - LV
- right pulmonary - RA
what are the four borders of the heart?
- superior
- inferior
- left
- right
what is the loose fitting sac around the heart called and what is it made of?
pericardium - double walled fibroserous membrane
what is the serous pericardium split into?
visceral / parietal
what does the parietal pericardium form?
epicardium - thin external layer
what is the function of the pericardium?
- fixation of heart
- prevents overfilling
- lubrication
- protection from infection
how are the pericardial sinuses formed? what are the two sinuses and where are they found?
embryological folding of primordial heart
- transverse: separates the heart’s arterial outflow - posterior to aorta and pulmonary trunk - can pass a finger through (surgeons use this for cardiac surgery/ clamps)
- oblique: blind recess partly covering the SVC/IVC/pulmonary veins
which veins/arteries supply the pericardium?
- pericardiophrenic artery - main supply (branch of internal thoracic artery)/ other arteries: musculophrenic/ bronchial/ esophageal/ superior phrenic/ coronary
- pericardiophrenic veins and azygos veins
what are the other two external layers of heart?
- myocardium = cardiac muscle
- endocardium = internal layer of endothelium/ sub-endothelial connective tissue
where does the right atrium receive blood from?
venous blood from SVC/IVC
what is an auricle?
atrial appendage - muscular pouch that increases capacity of atrium on anteromedial portion
(represents primordial atrium)
how is the interior of the right atrium split?
atrium proper - anterior to cristae terminalis - rough muscular wall due to pectinate muscles
sinus venarum - posterior to cristae terminalis - smooth walls - incorporates sinus venosus