Inotropics

Question 1

What are the classes of drugsnused in treating decompensated HF?

Answer 1

Loop Diuretics
Beta Blockers
Cardiac glycoside
Beta-1 Agonists
PDE IIIa Inhibitor
Synthetic BNP
ACEI/ARB
Aldosterone Antagonists

Question 2

How do diuretics work as inotropic agents?

Answer 2

Decrease volume and preload;

Improve arterial distensibility

Question 3

Diuretics as Inotropics

Impt SE

Answer 3

Causes neurohormonal activation

Question 4

Diuretics as Inotropics

Contraindication

Answer 4

Hypovolemia

Question 5

How do Beta Blockers work as inotropic agents?

Answer 5

Block high circulating levels of catecholamines

Question 6

Beta blockers

Uses

Answer 6

Dramatically decreases mortality in CHF pts

Question 7

Beta blockers

Misc

Answer 7

Should be started at very low dose and ratchet up;

Do not stop suddenly

Question 8

Digoxin

Class

Answer 8

Cardiac glycoside

Question 9

Digoxin

MOA

Answer 9

Inhibits Na/K/ATPase –> increases contractility d/t more Ca;
Inc vagal activity to heart (dec firing rate, dec conduction through AV node)

Question 10

Digoxin

Uses

Answer 10

Improves LV function;
dec neurohormonal activation;
Inc vagal tone;
Normalizes arterial baroreceptors;
Decreases hospitalizations in CHF (no mortality benefit)

Question 11

Digoxin

Impt SE

Answer 11

Very narrow therapeutic-toxic window (–>arrhythmias)

Question 12

Digoxin

Misc

Answer 12

Eliminated in kidneys, so dose according to renal function

Question 13

How does Dobutamine work as an inotrope?

Answer 13

Beta-1 receptor agonist;

Positive inotrope and chronotrope

Question 14

Dobutamine

Uses

Answer 14

Acutely decompensated pts (about half will die after 6mos)

Question 15

Dobutamine

Impt SE

Answer 15

Quick acting, but can develop tachyphylaxis after 48hrs

Question 16

Dobutamine

Misc

Answer 16

No NE release;

Given IV

Question 17

Nesiritide

Class, Use, Misc

Answer 17

Synthetic BNP;
Doesn’t do much;
Given IV