what factors affect co
preload heart and afterload
what affects preload
volume of blood returning to heart
what affects the heart
anything that affects contractiltiy and heart rate
bradycardia and MI
what affects afterload
resistance that the heart encounters
what is cardiac failure
inability of the heart to pump at a sufficient rate to meet the metabolic needs of the tissues OR the ability to do so only at elevated pressures
what are the responses to cardiac failure
short term : activation of SNS to increase heart rate and contractility to increase CO
long term : activation of the RAS to increase fluid retention to increase CO
what does ang 2 do
increase hypertrophy, inflammation, fibrosis and decreases production of NO
when do natriuretic peptides get produced
when the heart walls are distended
what do natriuretic peptides do
they lead to vasodilation and decrease renin leading to decrease fluid retention
why are beta blockers effective in heart failure
they decrease the workload of the heart by decreasing heart rate and contractility
what does neprilysin do
facilitates the breakdown of ang 2 and natriuretic peptides
