Heart Flashcards
(21 cards)
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%
anterior cardiac veins drain into
R atrium
Lymphatic drainage of the heart
Myocardium + subendocardial tissue subepicardial lymphatic plexus inferior tracheobronchial lymph nodes R + L bronchomediastinal trunk R goes to lymphatic, L goes to thoracic
Symathetic inervation of heart
T1-5/6 lateral horns
cervical + thoracic sympathetic trunk
Sa + AV nodes
effects of sympathic inervation of heart
increase HR, dialation of coronary arteries
Parasympathetic inervation of heart
Vagus nerve
effects of parasympathetic inervation of heart
decreased HR
Vasoconstriction
reduced force of contraction
