Cardiovascular Physiology Flashcards
An increase in HR will ___ contractility
INCREASE
What is the positive staircase effect?
An increase in heart rate will increase contractility due to more calcium entering cells and taken up into the SR
What are some things to consider with heart failure?
- preload and afterload
- oxygen availability
- HR and rhythm
- myocardium and pathophysiology
HRrEF
Reduced ejection fraction heart failure
Systolic heart failure - how is ejection fraction altered?
Reduced!
Diastolic heart failure - how is ejection fraction altered?
Not changed!
Systolic heart failure involved poor _____
Contractility, thus ejection fraction is reduced
HRpEF
Preserved ejection fraction heart failure
Diastolic heart failure involves increased?
Diastolic pressures and normal ejection fractions
If there is an increase in preload, what will happen to the afterload?
INCREASES
If there is an increase in afterload, what will happen to preload?
INCREASES
Do changes in ionotropy affect preload and afterload?
Yes
Using the Fick principle to measure cardiac output, what is it based on?
Oxygen consumption!
What are the 4 types of cardiac work?
- Volume work
- Pressure work
- Minute work
- Stroke work/external work output
Volume work
Cardiac output
Pressure work
Aortic pressure
Minute work
Cardiac output X aortic pressure
=== volume work X pressure work
Stroke work/external work output
Stroke volume X aortic pressure
Why does the left ventricle work harder than the right ventricle?
Because systemic pressures»_space; pulmonary pressures
Largest percentage of oxygen consumption is for what type of cardiac work?
Pressure work (aortic pressure)
What 2 conditions increase pressure work?
Aortic stenosis
Hypertension
Sympathetic system ____ ionotropy
(+)
Parasympathetic system ____ ionotropy
(+)
Where does the parasympathetic affect ionotropy?
ONLY IN THE ATRIA!!
