Cardiovascular System - PRM Flashcards
Cardiac cycle
Complete heartbeat, consisting of contraction and relaxation of atria and ventricles
Cardiac Output
Amount of blood pumped one minute (normal is approx. 5 L)
Diastolic pressure
Force exerted when the heart is at rest
Frank Starling’s Law
A higher end-diastolic volume increases preload - thereby increasing stroke volume (and a more forceful contraction during systole)
Stroke Volume
The amount of blood ejected from the ventricles during each ventricular contraction
Pulse pressure
Systolic pressure minus diastolic pressure
Systolic pressure
Amount of pressure put on the vessel walls by pumping blood
Systolic pressure
Amount of pressure put on the vessel walls by pumping blood
End-diastolic volume
amount of blood in the ventricles just before systole (or at the end of diastole)
Preload
Amount of stretch of the ventricles from the end-diastolic volume
What are the 3 layers of the heart?
- endocardium
- myocardium
- epicardium (outer layer)
What percentage of blood passes into the ventricles before atrial contraction?
70%
What are the two Atrio-ventricular valves (AV valves)?
- Tricuspid
- Mitral (Bicuspid)
Chordae Tendinae
- Attached to edges of AV valve leaflets
- anchored to papillary muscles
- Prevent valves from being forced back into the atria during ventricular contraction
Pericardium
The fluid filled sac that surrounds the heart and the root of IVC and SVC
