Review of Cardiovascular System Flashcards
heart
muscular pump which moves blood to lungs and other tissue of body
systemic circulation
supplies tissue of body w/ nutrients and oxygen-rich blood
types of circulations
systemic
pulmonary
oxygenated blood in systemic circulation
returns FROM lung that is pumped FROM left ventricle THROUGH aorta and systemic arteries TO tissues where gas exchange occurs
deoxygenated blood in systemic circulation
returns TO right atrium FROM superior vena cava
deoxygenated blood in pulmonary circulation
pumped BY right ventricle THROUGH pulmonary arteries
what kind of blood is in capillaries of lungs?
blood is oxygenated
oxygenated blood in pulmonary circulation
return TO left atrium THROUGH pulmonary veins
cardiac perfusion
heart itself receives blood through coronary arteries which branches off aorta
when does heart receive blood
ONLY during relaxation d/t extreme pressure in heart during contraction
what does changes in pressure in heart determine?
determines flow of blood in heart => opening and closing of valves
blood moves along a what kind of pressure?
pressure gradient - high to low
what does valve contribute to
unidirectional flow of blood
diastole
opening av valves
closing semilunar valves
opening av valves (diastole)
blood return to heart through atria - force AV valves open
atria contract, forcing additional blood into ventricles
closing semilunar valves (diastole)
ventricular relaxation => ↓intraventicular pressure and blood flows back from arteries
which sound does diastole do?
closing of semilunar valves - 2nd heart sound
ventricular systole
closing av valves
opening semilunar valves
closing av valves (systole)
papillary muscles contract to stabilize valves
ventricles contract, forcing blood against AV valves
which sound does systole do?
av valves close - 1st heart sound
opening semilunar valves (systole)
contraction of ventricles, force semilunar valves open
blood rushes into pulmonary arteries and aorta
cardiac murmurs
abnormal sounds created by turbulemt blood flow in heart
cardiac murmurs causes
pericardial rub, fluid overload and valve disease
valve disorder occur most frequently where?
left side of heart
valve disorders
mitral stenosis & regurgitation
aortic stenosis & regurgitation
mitral stenosis
narrowing of valve b/w two left heart chambers
mitral regurgitation
abrnomal leaking of blood backwards
FROM left ventricule, THROUGH mitral valves
- valve not closing properly
aortic stenosis
aortic valve narrows and blood cannot flow normally
aortic regurgitation
leaking of aortic valve of heart => blood flows in reverse direction during ventricular diastole
FROM aorta INTO left ventricle
cardiac output
used to measure efficiency of heart to pump blood
cardiac output formula
CO = HR x SV
stroke volume
represent difference b/w amount of blood in ventricle after filling (EDV) and volume of blood remaining in a ventricle after contraction (ESV)
factors affecting stroke volume
preload
contractility
afterload
preload
filling of ventricles ie. venous return (affects EDV)
- too little or excessive preload => ↓CO
what does ↑HR and filling time result to
↓EDV and preload
frank-starling mechanism
↑venous return stretches muscle fibers to generate more contractile force
contractility
contractile strength idependent of muscle stretch
afterload
pressure the ventricles must overcome to force semilunar valves open and eject blood into arteries
cardiac reserve
max % increase of CO above normal resting levels - depends on preload
ie. ventricular filling, afterload
ie. resistance to ejection of blood from heart, contractility and HR
