Heart Flashcards
what do the right + left side do + what seperates them
(internal structure)
right: pumps to the lungs
left: pumps to the body
right + left side are separated by septum
describe AV + SV
(internal structure)
- each side has an atrium and ventricle, and they are separated by an atrioventricular valve (AV)
- valves are also present at the “exit” of the ventricles, called semilunar valves (SV)
describe external structure: coronary arteries + pericardium
- coronary arteries and veins supply blood to the heart muscle
- the pericardium is a fluid-filled sac that surrounds the heart
describe heart electricity: SA
SA node:
- Sinoatrial node
- hearts pacemaker
describe heart electricity: AV
AV node:
- atrioventricular node
- stimulates His bundle and Purkinje fibers
- causes ventricular contraction
cardiac cycle vocab
occurs simultaneously on the left and right sides
diastole: relaxed
systole: contracted
cardiac cycle
1) diastole: AV valves are open, and blood flows atrium to ventricle
2) atrial systole: the SA node sends an impulse triggering the atria to contract
3) ventricular systole: when the electricity reaches the AV node, it sends a signal through the ventricular muscle to cause it to contract. the AV valves close and blood is pushes out of the ventricles
4) ventricular diastole: the ventricles relax, semilunar valves close, the AV valves open, and the cycle restarts
what is lub-dub
sound the heart makes: sound made by the valves closing
lub: AV valves closing
dub: SL valves closing
what is arrhythmia
irregular heartbeat
- tachycardias: too fast
- bradycardias: too slow
see notes for electrocardiograms