Cardiac Biomechanics Flashcards
What is Diastole?
ventricular relaxation (and atrial contraction)
What happens when P(LV) < P (AO)?
aortic valve closes
What happens when P(LV) < P (LA)?
mitral valve (bicuspid valve) opens -> filling phase
What happens during systole?
ventricular contraction
What happens when P(LV) > P(LA)?
mitral valve closes
What happens when P(LV) > P(AO)?
aortic valve opens -> ejection phase
What is the preload in LV function?
maximum filling before contraction starts= End Diastolic Volume (EDV)
When does Atrial contraction begin?
same as ventricular relaxation (Diastole)
What is the afterload in LV function?
what the ventricle has to overcome before ejection starts= minimum P(AO)= Diastolic Blood Pressure (DBP)
During the Cardiac cycle pressure/volume loop, what is happened at 2?
preload (EDV), end diastolic pressure (EDP)
During the Cardiac cycle pressure/volume loop, what is happened at 3?
afterload (DBP= diastolic blood pressure)
During the Cardiac cycle pressure/volume loop, what is happened at 3 to 4 peak pressure?
maximum LV contraction pressure and maximum P(AO)= Systolic Blood Pressure (SBP)
During the Cardiac cycle pressure/volume loop, what is happening at 3 to 4 volume?
Stroke Volume (SV)- how much blood is ejected on 1 single heartbeat
What effects would increase the preload?
- Constrict veins/venules -> increases venous return/filling pressure
- Decrease heart rate-> increases filling time
What effects would increase the afterload (DBP)?
- constrict arterioles -> increase DBP
