Lecture 7 Alternative Treatments of Heart Failure

Question 1

How is spironolactone used to treat reduced ejection fraction in heart failure?

Answer 1

Improves survival in chronic heart failure, not used in cases of hyperkalaemia or renal impairment

Question 2

What type of drug is spironolactone (what happens when metabolised?)?

Answer 2

A pro-drug

Question 3

What is the active metabolite of spironolactone?

Answer 3

Canrenone

Question 4

What is the half-life of spironolactone?

Answer 4

10 mins - canrenone 9-16h

Question 5

What is the effect of spironolactone in the body?

Answer 5

Inhibition of aldosterone action on collecting duct
Important as they spare K+
Used in conjunction with other diuretics

Question 6

What is ivabradine?

Answer 6

Used for treatment of heart failure
Inhibits funny current which stops the reduction in cardiac pacemaker activity (SAN activity)

Question 7

What is the main function of ivabradine?

Answer 7

Slowing heart rate which inhibits the compensatory mechanisms in the heart

Question 8

What are the contra-indications of ivabradine?

Answer 8

Myocardial infarction, cardiogenic shock, heart block, slow heart rates

Question 9

What are the cautions with ivabradine?

Answer 9

Ineffective in atrial fibrillation, elderly and angina

Question 10

What are the side effects of ivabradine?

Answer 10

Arrhythmias, AV block, dizziness and headache

Question 11

What is Sacubitril valsartan?

Answer 11

Combination therapy - prodrug (sacubitril) inhibit breakdown of natriuretic peptides - increased diuresis and vasodilation and ARB (angiotensin-II blocker) - reduced BP

Question 12

When is sacubitril valsartan used?

Answer 12

In patients not taking an ACE inhibitor or an ARB

Question 13

What are the contra indications of sacubitril valsartan?

Answer 13

Do not use if blood pressure is <100mmHg

Question 14

What are the side effects of sacubitril valsartan?

Answer 14

Anaemia, cough, diarrhoea, dizziness, headache, hypotension and nausea

Question 15

What is hydralazine with nitrate?

Answer 15

Hydralazine - arterial vasodilator, reduce afterload and increase stroke volume
Nitrate - venodilator, reduce preload which reduced risk of pulmonary congestion

Question 16

When is hydralazine with nitrate used?

Answer 16

When a patient is intolerant to ACE inhibitors and ARBs

Question 17

What are the contraindications of hydralazine with nitrate?

Answer 17

Acute porphyrias (blood disorders), cor pulmonale, dissecting aortic aneurysm, poor function mechanical obstruction, tachycardia

Question 18

What are the side effects of hydralazine with nitrate?

Answer 18

Angina, headache, tachycardia, diarrhoea, dizziness, hypotension

Question 19

What are the cautions of hydralazine with nitrate?

Answer 19

Cerebrovascular or coronary artery disease

Question 20

What is digoxin?

Answer 20

A antiarrhythmic drug (increase vagal tone) and positive inotrope (increase intracellular Ca2+)

Question 21

How does digoxin increase vagal tone?

Answer 21

Slows the parasympathetic nerve

Question 22

What are the indications for usage of digoxin?

Answer 22

Chronic heart failure - improve symptoms not mortality rates
Supraventricular arrhythmias
Chronic atrial fibrillation

Question 23

What is the mechanism of action of digoxin?

Answer 23

It blocks the Na+/K+ ATPase causing Ca2+ stores to remain in the myofibril which increases the contraction in myofibrils

Question 24

What are the pharmacokinetics of digoxin?

Answer 24

Oral bioavailability: 75%
Onset action ~30mins
Peak effect 1-5h
Half-life 36h
Elimination ~70% renal
Narrow therapeutic range

Question 25

What are the contraindications of digoxin?

Answer 25

Heart block

Question 26

What are the cautions of digoxin?

Answer 26

Digitalis (foxglove) toxicity with electrolyte imbalances and recent myocardial infarction

Question 27

What are the common side effects of digoxin?

Answer 27

Arrhythmias, cardiac conduction problems, diarrhoea, dizziness, nausea, skin reactions, vision disorders and vomiting

Question 28

What is dapaglifozin used for?

Answer 28

Treatment of T2D and heart failure

Question 29

What is the mechanism of dapaglifozin?

Answer 29

Blocks the SGLT2 glucose transporter in PCT (glycosuria and fluid loss)

Question 30

What are the benefits of dapaglifozin?

Answer 30

Hemodynamic changes: Reduction in preload and afterload Cardiac function improves

Question 31

What are the adverse effects of dapaglifozin?

Answer 31

Rare severe ketacidosis

Question 32

What are the contraindications of dapaglifozin?

Answer 32

Diabetes ketoacidosis

Question 33

What are the cautions of dapaglifozin?

Answer 33

Elderly, hypotension, risk of volume depletion