cardiac hemodynamics Flashcards
the ability to do work is which type of energy
potential
energy of motion is which type of energy
kinetic
normal BP
120/80
high Bp
> 140/90 ON 2 OCCASION
average pressure over the cardiac cycle is?
mean pressure
the difference of pressure between two adj areas within the heart is….
pressure gradient
whats the natural flow direction
high to low
4 phases of cardiac cycle
- IVCT
- systole
- IVRT
- diastole
describe what is happening during IVCT including the length of time
“same volume”
- between MV closure and AV opening
- rising pressure in LV from 5-80
- ventricles start to contract
- lasts 30-50ms
describe what happens during ventricular systole
- LV/RV pressure exceeds semilunar valves
- finished when pressures fall below AV and PV
where does muscle contraction begin in ventricles and how long does ventricular systole last
apex to base
200-300ms
describe whats happening during IVRT and how long does it last
- constant volume, pressure falling in ventricles. Pressure in atria rise to prep for filling the ventricles
- 50-100ms
describe what happens in diastole including time
- time when MV TV open and blood moves from atria to ventricles .. pressures in ventricles fall below atria. finishes when LV pressure rises above LA and MV shuts. 150-220ms
stroke volume formula
SV=EDV-ESV
cardiac output formula
CO=SVxHR
Cardiac index formula
CI=CO/BSA
Stroke volume formula using doppler
SV=CSA x VTI
whats the oxygen saturation percentages in left and right side of the heart
98% left
75% right
not enough O2 and nutrients to the heart muscle is called???
angina pectoris
when affected arteries are blocked by 75%, angina pectoris is felt causing what?
ischemia
the amount of VOLUME of blood in the ventricle at end diastole is ??
preload
which law is this: heart adapts to different preloads by pumping the volume of blood delivered to it - the more blood that enters the heart, the greater the force of contraction required to elect the blood.
frank starling law of the heart
the degree of stretch of the cells in the ventricular wall determined by the volume of blood within the chamber.
frank starling principle
a slow HR has more time for ventricular filling leading to…
ventricular stretch
