The Cardiac Cycle Flashcards
systole occurs when
- contraction
- ventricular ejection
diastole occurs when
- relaxation
- ventricular filling
what is the highest pressures of the cardiac cycle
- systole
what is the lowest pressures of the cardiac cycle
- diastole
cardiac cycle starting at ventricular filling
what is happening with the valves?
- ventricular filling (AV valve open, aortic valve closed)
- atrial systole
- > AV valve closes
- isovolumetric contraction (AV and aortic valve closed)
- > aortic valve opens
- ejection -> aortic valve closes
- isovolumetric relaxation (AV and aortic valve closed)
- > AV valve opens
what makes up ventricular systole
- isovolumetric contraction
- ejection
LVEDV
volume in ventricle at end of atrial systole
just after mitral valve has shut
max amount of blood pumped into ventricle before ventricule started to contract
LVESV
- volume of blood found in heart after ventricle has ceased to contract
- at end of systole
stroke volume formula
LVEDV - LVESV
Ejection Fraction
SV/LVEDV
The amount of blood the heart pumps out per beat
1st heart sound heard because
- closure of AV valves
2nd heart sound heard because of
- closure of semilunar valves
3rd heart sound heard
due to
- after 2nd heart sound
- during opening of AV valves
tensing of chordae tendinae
rapid blood flow
4th heart sound heard
due to
- before 1st heart sound
- contraction of atria against stiff ventricle
which atrium contracts first?
- right atrium before left atrium
which ventricle contracts first
result
- left ventricle before right ventricle
- mitral valve closes before tricuspid and can sometimes get an S1 split
which valve shuts first?
- aortic valve shuts before pulmonary valve
- mitral valve shuts before tricuspid valve
label the waves
a - atrial systole
x- descent
c- contraction of ventricles
v- venous filling
y - descent
cause of C wave bump
- increased ventricular pressure during ventricular contraction causes teh AV valve to bulge back into the atrium
why can you hear a split S2 during inspriation?
- venous return to right atrium (and ventricle) increases, which delays pulmonaic valve closure even further.
we hear fixed splitting in what condition?
- atrial septal defect
