heart Flashcards
Mediastinum
Where heart is located.
region extending from the sternum to the vertebral column, the first rib and between the lungs.
Mediastinum apex
at tip of left ventricle
Mediastinum base
is posterior to surface
Mediastinum anterior surface
deep to sternum and ribs
Mediastinum Inferior surface
between apex and right border
Mediastinum right boarder
faces right lung
Mediastinum left border
faces left lung
Pericardium
membrane surrounding and protecting the heart
confines while still allowing free movement
Pericardium 2 main parts
- fibrous pericardium
- serious pericardium
fibrous pericardium
-tough
`inelastic
-dense irrregular connective tissue
-prevents overstretching, protection, and anchorage
serious pericardium
thinner, more delicate membrane
-double layer
!. parietal layer fused to fibrous
2. visceral layer=epicardium
Pericardium fluid
reduces friction
-secreted into pericardial cavity
Layer of the heart wall
-epicardium
myocardium
-endocardium
epicardium
external layer
- visceral layer of serous pericardium
- smooth, slippery texture to outermost surface
myocardium
95% of heart is cardiac muscle
endocardium
inner layer
-smooth lining for chambers of heart, valves and continuous with lining of large blood vessels
Number of chambers in heart
4
Atria
- 2
- receiving chambers
- auricles increase capacity
Ventricles
- 2
- pumping chambers
Sulci
grooves
- contain coronary blood vessels
- coronary sulcus
- anterior interventrivular sulcus
- posterior interventrivular sulcus
Right atrium
receives deoxygenated blood from body
- superior vena cava
- inferior vena cava
- coronary sinus
right atrium details
- interatrial spetum has fossa ovalis
- remnant of formanen ovale
- blood passes through tricuspid value(right atrioventricular valve) into right ventricle
left atrium
recieves oxygenated blood from lungs
right ventricle
recieves deoxygenated blood from right atrium and sends it to lungs
left ventricle
recieves oxygenated blood from left atrium and sends it to body
right ventricle deatils
- forms anterior sruface of heart
- tricuspid valve connected to chordate tendinae connected to papillary muscles
- interventricular septum
right ventricle: trabeculae carneae
ridges formed by raised bundles of cardiac muscle fiber
-part of conduction system of heart
right ventricle blood flow
through pulminary semilunar value into pulmonary trunk and then right and left pulminary arteries
left atrium details
- about same thickness as right atrium
- recieves blood from lungs thorugh pulminary veins
- passes through bicuspid/mitral/left artioventricular valve into left ventrice
Left Ventricle details
- thickest chamber of heart
- forms apex
- chordae tendinae attached to papillary muscles
Left Ventricle blood flow
blood passes through arotic semilunar valve into ascending aorta
-some blood flows into coronary artiers, remainder of body
Left Ventricle fetal
during fetal life ducus arteriosus shunts blood from pulmonary trunk to aorta( lung bypass)
-closes after birth with remnant called ligamentum arteriosum
Myocardial thickness
- thin walled atria deliver blood under less pressure to ventricles
- right ventricle: shorter distance, lower pressure, less resistance
- left ventricle: longer distance, higher pressure, more resistance
- left ventricle works harder to maintain same rate of blood flow as right ventricle
