4.5 Heart Failure Drugs

Question 1

Reduced contractility along with decreased ejection fraction (pumping less blood)

Answer 1

Systolic failure

Question 2

• Reduced Filling + CO, due to:
  
  • Stiffness
  • Loss of adequate relaxation

Heart is not stretching enough to fill up

Answer 2

Diastolic Failure

Question 3

What is the effect of CHF on contracility, HR, preload + afterload?

Answer 3

• Decreased:
  
  • Contractility
• Increased:
  
  • HR
  • Preload
  • Afterload

Question 4

Why is HR increased in congestive heart failure?

Answer 4

Sympathetic activation of beta-adrenergic receptors

Question 5

Why is preload increased in congestive heart failure?

Answer 5

Increased BV + venous tone

Question 6

Why is afterload increased in congestive heart failure?

Answer 6

Increased systemic vascular resistance

Question 7

What problem is associated with pts taking ACE Inhibitors?

Answer 7

• ACE is also responsible for the breakdown of bradykinin
  
  • ACE converts Angiotensin I to Angiotensin II
• Pts taking ACE Inhibitors get an acculumation of bradykinin resulting in persistent cough , etc.

Question 8

Are beta-adrenergic blockers or agonists used for Chronic or Acute CHF?

Answer 8

• Chronic CHF
  
  • beta-adrenergic blockers
    
    • ​metoprolol
• Acute CHF
  
  • beta-adrenergic agonists
    
    • ​dobutamine, dopamine

Question 9

What are the ACE Inhibitors used in the tx of Chronic CHF? (4)

Answer 9

- prili = ACE Inhibitors

• Benazepril
• Captopril
• Enalapril
• Lisinopril

Question 10

What are the cardiac effects of ACE Inhibitors? (2)

Answer 10

• Reduce:
  
  • Peripheral Resistance
  • Afterload
  • Aldosterone secretion
  • Sympatethic activity
    
    • via inhibition of angiotensin
• Prevent Myocardial Remodeling

Question 11

What are the Angiotensin II Type-1 Receptor Blockers? (3)

Answer 11

- sartan

• Losartan
• Velsartan
• Olmesartan

Question 12

What drugs are considered in pts intolerant to ACE Inhibitors due to incessant cough?

Answer 12

Angiotensin II Type-1 Receptor Blockers

Losartan, velsartan, olmesartan

Question 13

What is a plant derived cardiac glycoside (only cardiac glycoside used in USA)?

Answer 13

Digitalis/Digoxin

Question 14

In what form is digitalis/digoxin active, and what is the half life?

Answer 14

• Orally active
• Long 1/2 life = 36-40 hrs

Question 15

How is digitalis/digoxin excreted?

Answer 15

excreted in kidneys

Question 16

What is the mechanism of action of Digoxin?

Answer 16

• Inhibits the Na⁺/K⁺ ATPase
• Thus increases intracellular Na⁺, which in turn inhibits Na⁺/Ca²⁺ exchanger (NCX)
• Which leads to the retention of intracellular calcium, causing increases myocardial contractility

Question 17

What effect does Digitalis have on the CNS?

Answer 17

• Disorientation
• hallucinations

Question 18

What effect does Digitalis have on the GI tract?

Answer 18

• Anorexia
• Nausea
• Vomiting
• Diarrhea

Question 19

Gynecomastia may occur in men who take …

Answer 19

Digitalis

Question 20

What effect does Digitalis have on potassium?

Answer 20

Hypokalemia

• Potassium + digitalis compete for the binding to Na⁺/K⁺-ATPase
• Postassium supresses the efficacy of digitalis
• Reducing the toxicity of digitalis

Question 21

What effect does Digitalis have on Magnesium?

Answer 21

Hypomagnesemia

• Increasing susceptibility to Digoxin toxicity

Question 22

What effect does Digitalis have on calcium?

Answer 22

Hypercalcemia

• Increasing the risk of digitalis-induced arrhythmia

Question 23

What drug is a Calcium Sensitizer?

Answer 23

Levosimendan

Question 24

What is the clinical benefit from Levosimendan (calcium sensitizer)?

Answer 24

Vasodilation

• Opens ATP-sensitive K-channel

Question 25

What drugs are **beta-adrenoceptor agonists**?

Answer 25

* Dobutamine * Dopamine

Question 26

What drug is a **selective beta₁ agonist**?

Answer 26

Dobutamine

Question 27

What receptors are effected with **low dose Dopamine**?

Answer 27

D-dopaminergic receptor

Question 28

What receptors are effected with **high dose Dopamine**?

Answer 28

beta₁ receptor

Question 29

What drug(s) are **arrhytmogenic in CHF pts**?

Answer 29

**Dobutamine + Dopamine** Beta-adrenoceptor agonists

Question 30

What drugs are **Phosphodiesterase-III Inhibitors**?

Answer 30

Inamrinone + Milrinone

Question 31

What is the effect of inhibiting PDE-III?

Answer 31

cAMP elevation

Question 32

What are PDE-III Inhibitors (Inamrinone + Milrinone) used to treat?

Answer 32

Acute Heart Failure

Question 33

Inamrinone + Milrinone (PDE-III Inhibitors) are only available ...

Answer 33

parenterally

Question 34

Which PDE-III Inhibitor is less liver toxic?

Answer 34

Milrinone

Question 35

What drug is a Natriuretic Peptide?

Answer 35

Nesiritide

Question 36

What is **Nesiritide** a synthetic form of?

Answer 36

Endogenous BNP

Question 37

What are potential toxic effects of **Nesiritide** (Natriuretic Peptide)?

Answer 37

* Excessive **hypotension** * Even **death**

Question 38

What diuretic is suitable for **systolic heart failure?**

Answer 38

Furosemide

Question 39

What diuretics are aldosterone antagonists?

Answer 39

Spironolactone + Eplerenone

Question 40

Spironolactone + eplerenone should be concomitantly used with ...?

Answer 40

ACE Inhibitors

Question 41

What drugs are **beta-adrenoceptor blockers**?

Answer 41

* Metoprolol * Nebivolol * Carvedilol

Question 42

What are the effects of **beta-adrenoceptor blockers** (metoprolol, nebivolol)? (3)

Answer 42

* **Reduce mortality** in pts with **severe chronic heart failure** * Reduce adverse effects of high concentrations of catecholamines * Reduce remodeling effects of catecholamines

Question 43

What is the effect of **carvedilol** (beta-adrenoceptor blocker)?

Answer 43

Reduces pre- and after-load, and antioxidant action

Question 44

What drug is a direct vasodilator?

Answer 44

Hydralazine

Question 45

Hydralazine (direct vasodilator) is combined with ...?

Answer 45

inotropic agents

Question 46

What is used to treat: * Advanced stage heart failure * Resistant cases * Pts that cannot tolerate other medications

Answer 46

Hydralazine + isosorbide dinitrate

Question 47

Use of **muscarinic (agonists)** drugs may have what side effect?

Answer 47

Increase HR

Question 48

What drug increases digoxin uptake in GI?

Answer 48

Antibiotics (macrolides, tetracyclines)

Question 49

What drugs may antagonize digoxin?

Answer 49

Antimuscarinic drugs