Heart Flashcards
3 layers of the heart
- epicardium (outer layer)
- Myocardium- muscle layer
- Endocardium- made up of endothelium + it lines the heart valves
4 surfaces of the heart
- Anterior (sternocostal)- formed mainly by the r. ventricle
- Diaphragmic (inferior)- formed by l ventricle + part of R ventricle
- L. pulmonary surface- mainly L ventricle
- R. pulmonary surface- mainly R. ventricle
what are the purpose of auricles
if atria are overfilled w blood, act as back up area for blood to fill + protect coronary vessels
what nerves supply diaphram
R + L phrenic nerves
what are the walls of the ventricles made up of
trabeculae carneae
which valves are opended by blood flow and which are opended due to muscular contraction
blood- aortic semilunar vales
muscle- bi and tricuspid valves
what are the walls of the atria made up of
Pectinate muscles (left ones thicker)
what are the first branches off accending aorta
R+L coronary artieries
What does R marginal branch, conducting system branch and av node branch supply
marginal- R. border of heart
Conducting- SA node
AV- Av
What does R coronary artery supply
- R. atrium
- R. ventricle
- Part of the L ventricle
- posterior 1/3 of interventricular septum
- AV node in 80% of ppl
- SA node in 60% of ppl
Conduction of heart steps
SA node- pacemaker of heart (hyper excitable)
myogenic conduction gets AV node to fire
AV node stims R/L AV bundles
stim sub endrocardial branges which stim ventricles
flow of heart blood
Left coronary- anterior interventricular- lateral diagonal
left coronary- left circumflex- 1. left marginal OR 2. posterior interventricular artery
left atrium supplies
left side of heart
- most of l ventricle and some r ventricle
Anterior interventricular branch supplies
most of L ventricle (“widowmaker”)
% of R domiant hearts, Codominant and Left dominant
R- 70%
L- 10%
co- 20%
