Physiology Flashcards
What drugs stimulate cardiac apoptosis
Beta aganosits
Anthracyclines
What inhibit apoptosis
Igf, il6 , activators of Gi
What activate mmps
Endothelins, angiotensin, catecholamines
How do nitrates work?
Increase soluble guanylate Cyclase leads to cgmp and vasodilation
How does milrinone work
Inhibit pde3 prevents breakdown of camp leads to more play
How does dig work
Inhibit sodium k ATP ass more intracellular calcium
Law of Laplace
Preload
Afterload
Wall stress=pressure*radius\wall thickness
Preload lv stress during filling, a load before you stimulate it.
Afterload lv stress during diastole
Changes in preload lead to how much change in volume
10-15% (ie co from 5-6).
What is aortic bp
Stroke volume x peripheral vascular resistance
When aorta opens abp =Afterload
What is tau
Time it takes for pressure to drop by 2/3
As pressure goes up, Afterload is slower
Why do people in heart failure get short of breath with exertion
Higher left atrial pressures needed to fill ventricle.
How does pressure go up with same volume
Change in stiffness.
Calculate rvswi
Mpap-cvp x sv
Difference between changes in cell in Volume overload and pressure overload
Volume is increase in series
Pressure in changes in parallel
Mmp/timp
Mmp decrease collagen, timp increase collagen
