The Cardiac Cycle Flashcards
What is the isovolumic contraction?
Between the start of ventricular systole + opening of the semilunar valve when ventricular Pressure rises abruptly
Which wave represents atrial systole?
P Wave
What represents the R phase?
Isovolumic contraction
What is congestive heart failure?
Volume overload as walls are stretched maximally.
What is the key sign of congestive heart failure?
3rd heart beat - “Galloping heart”
What marks the onset of ventricular ejection?
Opening of the semilunar valves
What are the different wave forms?
A wave: atrial contraction
C wave: Abrupt closure of tricuspid caused by common carotid artery
V Wave: Atrial filling
What produces the second heart sound?
Incisure - closing of aortic valve
What affect do catecholamines have on the heart?
- INC myocardial contractility
- INC SV
- INC EF
What is the effect of digitalis on the heart?
INC myocardial contractility
How does increased ventricular contractility change stroke volume?
Increases stroke volume
How does cardiac ischemia affect stroke volume?
Reduces Stroke volume
Hoe do calcium channel blockers affect stroke volume?
Reduce stroke volume
Describe the relationship between myocardial wall stress and myocardial afterload.
- Wall Stress = Pressure X radius / Wall thickness
- Afterload = Pressure at which the heart has to pump out of ventricle against Aorta
Where is the tricuspid valve heard?
5th intercostal space left of sternum
