Lecture 19: Circulatory System 1 Flashcards
explain contents of mediastina
heart
large vessels
esophagus
trachea
thoracic aorta
explain borders of mediastina
bounded anteriorly by sternum and costal
cartilages, laterally by lungs, and posteriorly by the bodies of thoracic
vertebrae
explain subdivisions mediastina
divided into superior and infeior by a transverse plane passing thru sternal angle
superior mediastinum:
inferior mediastinum
middle mediastinum: heart & pericardium
anterior mediastinum: by ribs
posterior: by thoracic vertebrae
discuss external features heart
heart sulci- coronary sulcus separates atria from ventricles. anterior and posterior interventricular sulci are btw ventricles.
heart surfaces- anterior, inferior, left and right pulmonary surface
heart borderes- superior, right, eft, inferior
heart base- faces posteriorly, mainly left atrium
heart apex- formed by left ventricle and is directed anteriorly, inferiorly, to the left
discuss internal features heart
R atrium: receives venous blood from SVC, IVC, coronary sinus
R ventricle: pulmonary artery arises
L atrium: receives oxygenated venous blood from R and L pulmonar veins
L ventricle: aorta arises from here
explain blood supply/venous drainage heart
right atrium receives deozxygenated blood from entire body, passes it to right ventricle. right ventricle pupms blood to lungs, left atrium receives oxygenated blood from lungs, pumps to body
contents of superior mediastinum
Arch of aorta
R and L brachiocephalic veins
Inferior part of superior vena cava, azygos vein
Right and left phrenic and vagus nerves
Trachea, esophagus, thynus gland, thoracic duct
explain contents inferior mediastinum
anterior: thymus gland
middle: heart, pericardium, ascneindg aorta, pulmonary trunk/veins. phrenic nerves. bronchi
posterior: descending aorta, azygos and hemiazygos viens, vagus nerves, splachnic nerves, thoracic duct, esophagus
what is circled in orange? green? blye?
orange: anterior mediastinum
green: middle
blue: posterior
- right pulmonary surface
- diaphragm
- left pulmonary surface
- apex of heart (L side)
- inferior surface
what are the four corners of the surface anatomy of the heart?
Upper left corner= left 2nd intercostal space, 1 in ch away from midline
Upper right corner is right 3rd costal cartilage, 1 inch from mid
lower right corner is at 6th costal cartilage, 1 inch from midline
lower left corner is 5th intercostal soace, 3-4 inches from midline
what is the heart surrounded by? what is this made of?
=pericardial sac which is composed of outer layer (fibrous pericardium) and inner serous layer (serous pericardium)
what is the serous pericardium? whats it made of
inner layer of pericardium. hhas two layers
- parietal layer: lines inner surface of fibrous pericardium
- visceral layer: attaches to heart surface
pericardial cavity in btw the layers, filled with serous fluid
what is the visceral layer of serous pericardium AKA
epicardium (outermost part of heart)
what is the myocardium
middle muscular layer of heart
what is endocardium
inner layer of heart. blood.
which part of heart receives oxygen rich blood?
LEFT ATRIUM, then blood goes to left ventricle, blood pumped into systemic circulation
which part of heart receives deoxygenated bloo?
right atrium. pumped into right ventricle, then to lungs