Heart Failure

Question 1

Goals of treating HF

Answer 1

• Relieve symptoms
• Slow or reverse deterioration in myocardial function
• Improve patient survival

Question 2

How do inotropic agents work?

Answer 2

• Increase force of contraction

which is often times a problem with patients in heart failure

Question 3

Inotropic Agents are only used in ____ HF

Answer 3

severe

Question 4

inotropic use for HF patients

Answer 4

Used for low-output HF and systolic HF (patients with reduced EF)

Question 5

what inotropic agent would you use for short AND long term use

Answer 5

Digoxin (Lanoxin, Digitek)

Question 6

what inotropic agents are short term use only?

Answer 6

o	Dopamine (IV ONLY)
o	Dobutamine (IV ONLY)
o	PDE Inhibitors:
	Milrinone (IV)
	Inamrinone (old drug not used much now)

Question 7

Digoxin MOA -Two major actions?

Answer 7

1. Positive inotropic effects: blocks Na/K ATPase pumps

2. Negative chronotropic effects: enhances vagal tone

Question 8

the Positive inotropic effects of digoxin works by blocking Na/K ATPase pumps, what happens when you block this?

Answer 8

♣ Na+ stays inside cell so slows down the Ca++/3Na+ exchanger OR even reverses the direction depending on concentrations
♣ The end result is more Ca++ inside the cell
♣ Increased intracellular Ca++ leads to increased contractility
Heart beats harder because there is more calcium readily available

Question 9

enhancing vagal tone is digoxin’s negative chronotropic effect, how does it do this?

Answer 9

♣ Suppresses AV node conduction to increase effective refractory period and decrease conduction velocity