CHF

Question 1

High output HF caused by?

CHF drugs to tx?

Answer 1

hyperthyroid, anemia, AV shunt

none - heart already working hard so inotropic (contractility) drugs don’t help

Question 2

Low output HF caused by?

Answer 2

HTN, MI, CAD

Question 3

Preload causes?

Answer 3

↑ stretch, ↑ contract, ↑ stroke vol

Question 4

CHF affects preload how?

Treat w/?

Answer 4

↑ preload:
↑ SNS and RAAS activity ->
↑ blood vol/venous tone -> ↑ venous return

diuretic/venodilators

Question 5

Afterload determined by?

Answer 5

arterial resistance

Question 6

CHF affects afterload how?

Treat w/?

Answer 6

↑ afterload:
aortic impediance and
↑ peripheral resistance (atrial constriction)

arteriodilators

Question 7

CHF affects contractility how?

What drugs ↑ contractility?

What drugs ↓ contr?

Answer 7

↓ contractility (mm stretched too far as vents dilate)

inotropics

B-block

Question 8

CHF affects HR how?

Treat w/?

Answer 8

CHF causes ↓ CO ->
↑ baro -> ↑ SNS -> tachy

B-block (↓ HR)

Question 9

Contractility determined by? (6)

Answer 9

1) contract protein sensitivity to Ca2+
2) amount of Ca2+ release from SR
3) amount of Ca2+ stored in SR
4) amount of trigger Ca2+
5) activity of Na+/Ca2+ exchange
6) [Na+] and Na+/K+ATPase