heart
covered in a double layer of serous membranes called visceral and parietal pericardium (thin membranes)
fibrous pericardium
tough fibrous sac that covers the heart and serous membrane
divisions of heart
divided into right and left sides and has 4 chambers (2 atria and 2 ventricles)
anatomical position
heart is rotated towards left (right ventricle is most anterior chamber; left atrium is most posterior chamber)
heart function
pump blood throughout the body
right side of heart
receives blood from veins of the body and pumps blood to the lungs
pulmonary circulation
blood traveling to and from the lungs is part of the pulmonary circulation; arteries carry deoxygenated blood and veins carry oxygenated blood
systemic circulation
blood traveling to and from body tissues is part of the systemic circulation; arteries carry oxygenated blood and veins carry deoxygenated blood
heart valves
allows blood to flow from one chamber to the next; prevents backward flow of blood (produced lub-dub sound when closing); divided into 4 heart valves (atrioventricular and semilunar)
atrioventricular (AV) valves
between the atria and ventricles; includes tricuspid valve and bicuspid/mitral valve
tricuspid valve
between right atrium and right ventricle
bicuspid/mitral valve
between the left atrium and left ventricle
semilunar valves
between the ventricles and their outflow tracts (named for half-mooned shape); includes pulmonary valve and aortic valve
pulmonary valve
between the right ventricles and pulmonary trunks
aortic valve
between the left ventricle and aorta
cardiac blood flow
atria
much thinner walled than the ventricles
interatrial septum
separates left and right atriums
pectinate muscles
raised muscles in the mostly smooth-walled atria
right atrium
contains openings for superior vena cava (SVC), inferior vena cava (IVC), and coronary sinus; outflow is gated by tricuspid valve
auricle
pocket-like flap (another term for atrium)
left atrium
contains openings for the 4 pulmonary veins; outflow gated by the mitral valve
ventricles
thicker walls than atria
interventricular septum
separates right and left ventricles
papillary muscles
muscles in ventricles which are attached to cords called chordae tendineae
chordae tendineae
cords that are attatched to valve leaflets of the atrioventricular valves (right ventricle- tricuspid valve; left ventricle-mitral valve)
function of papillary muscles
prevents backward flow of blood through the heart by keeping AV valves closed during a heartbeat when the heart muscle contracts (via the chordae tendineae)
great vessels
large blood vessels that enter/exit the heart
great vessels carrying deoxygenated blood
superior vena cava (SVC), inferior vena cava (IVC), pulmonary trunk
superior vena cava
collects blood from the head, neck, upper limb, and chest wall; formed by the union of the right and left brachiocephalic veins
inferior vena cava
collects blood from the abdomen, pelvis, and lower limbs
great vessels carrying oxygenated blood
pulmonary veins (4), aorta
pulmonary veins
4 pulmonary veins carry blood from the lungs (2 from each lung) to the left atrium
aorta
distributes blood to all parts of the body (via many branching arteries); shaped like a candy cane (makes a 180 degree turn and travels down into the abdomen)
ascending aorta
gives off the right and left coronary arteries; branches in these arteries travel to surface of heart itself to supply it
aortic arch
arch portion shave 3 branches; (right to left) brachiocephalic trunk, left common carotid artery, left subclavian artery
brachiocephalic trunk
divides into right subclavian artery and right common carotid artery
right subclavian artery
supplies the right upper limb
right common carotid artery
travels up the right side of the neck and supplies the head
left common carotid artery
travels up the left side of the neck and supplies the head
left subclavian artery
supplies the left upper limbs
coronary circulation
the heart's own blood supply
coronary arteries
distribute blood throughout various regions of the heart
coronary veins
collect deoxygenated blood from heart and returns it to right atrium through the coronary sinus
coronary sinus
large vein on the back of the heart which returns the deoxygenated blood from the coronary veins to the right atrium