Drugs for Heart Failure etc.

Question 1

What’s the good, bad, and ugly about digoxin

Answer 1

good: symptomatic relief of heart failure
bad: only short term benefit, narrow therapeutic window
ugly: risk of dysthythmias

Question 2

How exactly does digoxin work?

Answer 2

inhibits Na+/K+ pump thus increasing intracellular Na+, decreasing Ca2+ extrusion, more Ca2+ in cell for increased contractility

Question 3

What is used for chronic symptomatic relief of heart failure and considered an inotrope?

Answer 3

Glycosides

Question 4

What drug has a risk of hypokalemia?

Answer 4

Digoxin

Question 5

What is Amrinone?

Answer 5

Phosphdiesterase inhibitor for short term support of actue heart failure: increases cAMP to increase Ca2+

Question 6

example of B-adrenoceptor agonists?

Answer 6

NA, Adrenaline (alpha and beta), dobutamine (B1)

Question 7

What’s the risk of using B-adrenoceptor agonist in chronic heart failure?

Answer 7

desensitization of B1-adrenoceptors to sympathetic drive

Question 8

What’s the class of drugs used to increase short term contractility of cardiomyocytes?

Answer 8

Inotropes

Question 9

2 mechanisms of pressure overload

Answer 9

1. hypertension

2. aortic stenosis

Question 10

2 mechanisms of volume overload

Answer 10

1. valve regurgitation

2. shunts

Question 11

Explain the bad positive feedback loop of compensation in decreased CO

Answer 11

beta - activates renin-angiotensin system
alpha - vasoconstriction
All lead to worse function and remodelling which leads to more decreased CO

Question 12

How do you reduce preload?

Answer 12

1. Venodilators: nitrates
2. Diuretics
3. aldosterone receptor antagonists
4. aquarectics

Question 13

Name a diuretic

Answer 13

furosemide at loop of Henle

Question 14

What’s an aquaretic?

Answer 14

vasopression receptor antagonist

Question 15

example of an aldosterone receptor antagonist?

Answer 15

Spironolactone

Question 16

What is spironolactone? how does it work?

Answer 16

1. aldosterone receptor antagonist
2. inhibits on distal tubles (spares K+)
3. needs monitoring of hyperkalemia

Question 17

4 drug classes that reduce afterload?

Answer 17

1. arterial vasodilators
2. ACE inhibitors (first line)
3. AT1 antagonist
4. Beta adrenoceptor antagonists

Question 18

What is the first line therapy for all grade of heart failure?

Answer 18

ACE inhibitors

• improve symptoms, delay progression
• needs titrating

Question 19

what are ACE inhibitors contraindicated in?

Answer 19

1. Preg
2. renal stenosis
3. angioneurotic oedema

Question 20

Should you combine ACE inhibitors with anything?

Answer 20

Yes, such as diuretics, glycosides, B-antagonists

Question 21

What’s paradoxical about beta antagonist for heart failure?

Answer 21

despite B1 blockade, SV increases!

Question 22

When do you use B-adrenoceptor antagonists?

Answer 22

early stages the ‘-olols’