CV Anatomy Flashcards
SV is the difference btwn…
End diastolic volume (EDV—amt blood at end of relax) AND end systolic volume (ESV—residual volume blood remaining in vent after ejection)
Preload
Volume of blood in the heart
- stretch of cardiac muscle cells before ctx
- dec with hypovolemia
Frank-Starling law
An inc in resting muscle fiber length results in greater muscle tension
- aka length-tension relationship
- heart can chx force of ctx (and SV) in response to chx in venous return
Where is ECF located
Inside the capillary
Oncotic (osmotic) pressure
Pulls fluid from interstitial and Intracellular spaces into the capillary
Sterling’s law of capillary forces
Oncotic pressure forces and hydrostatic pressure forces oppose each other at every capillary membrane and attempt to balance each other out.
Afterload
Force opposing ejection of blood from the ventricles
- resistance to overcome to eject blood from the chambers
Left ventricular Afterload is primary determined by…
Aortic BP
Inc in Afterload will lead to dec in…
SV unless heart compensates
Main determiner of contractility
Amt of free Ca w/i myocardial cell
Effect of a failing left vent causes…
Build up of hydrostatic pressure in left atrium, pulmonary veins, and pulmonary capillaries AND dec perfusion of brain, kidneys, other organs
Plum edema with LVF
- mild or severe
- crackles in lungs (fine with mild, coarse with severe)
- pink, frothy sputum with severe pulmonary edema
LVF stims what compensatory systems?
RAAS, ADH, SNS (baroreceptors trigger adrenergic stimulation)
