Heart Failure

Question 0

What are common causes of heart failure ?

Answer 0

Ischaemic heart disease
Cardiomyopathy
Hypertension
Idiopathic causes seen due to mutations of proteins in cardiac tissue

Question 1

What is heart failure ?

Answer 1

Complex syndrome that results from any structural or functional disorder which impairs the ability of heart to function as a pump to support physiological circulation

Question 2

What are the symptoms of heart failure ?

Answer 2

Fatigue
Dyspnoea
Odema

Question 3

What are the signs of heart failure ?

Answer 3

Pulmonary oedema 
Peripheral oedema 
Ascites
Liver enlargement 
Raised jugular venous pressure

Question 4

What are the subdivisions of chronic hf ?

Answer 4

Systolic- large dilated heart that can’t eject blood properly
Diastolic- impaired filling due to stiffness
Right sided- impaired right ventricular function causing peripheral congestion
Left sided- impaired left ventricular function causing pulmonary congestion
Congestive- symptoms of circulatory congestion

Question 5

Who is at a greater risk men or women ?

Answer 5

Men

Question 6

What are the aims of treatment in hf ?

Answer 6

Relieve symptoms
Improve exercise tolerance
Reduce mortality

Question 7

What do the secondary changes of heart do ?

Answer 7

Try to overcome the primary malfunctions of the heart but they then lead to other problems

Question 8

What are the 3 maladapatations of hf ?

Answer 8

Autonomic dsyfunction- increase sympathetic drive and decrease para drive
Neurohumoral adaptations - renin angiotensin system, vasopressin and endothelium-1
Structural changess- hyper trophy, fibrosis

Question 9

What are the maladaptive consequences of hf ?

Answer 9

Vasoconstriction - increases after load

Fluid retention - increases preload

Question 10

In chf the SV doesn’t increase alongside the increased preload, what effect does this have and what treatments are needed ?

Answer 10

Leads to ventricular filling pressure reaching very high levels causing congestive symptoms
Treatment is to decrease fluid retention so preload is reduced to reduce pulmonary oedema and improve gas exchange

Question 11

How is the increased after load treated ?

Answer 11

Cause vasodilation to decrease after load so that the CO can increase

Question 12

What are the beneficial effects of beta- blockers in hf ?

Answer 12

Inhibits sympathetic output
3rd gen causes direct vasodilation
Helps to prevent hyper trophy occurring
Reduces dsyrythmias

Question 13

Give examples of beta blockers..

Answer 13

1st gen- non selective - propranolol
2nd gen - beta-1 selective - atenolol and bisoprolol
3rd gen- selective or non selective - carvedilol - causes vasodilation by causing NO release

Question 14

What are the adverse effects of beta blockers ?

Answer 14

Bronchoconstriction
Cold extremities
Fatigue
Sleep disturbance

Question 15

What happens when angiotensin 2 binds to at-1 receptors?

Answer 15

Causes the maladaptive changes vasoconstriction and fluid retention

Question 16

What do ACE inhibitors do and examples

Answer 16

Block angiotensin converting enzyme so prevent co version of angiotensin 1 to angiotensin 2 which reduces symptoms and increases exercise tolerance
Captopril and ramipril

Question 17

What are the adverse effects of ACE inhibitors?

Answer 17

Can lead to hypotension in patients using diuretics
Hyperkalemia
Avoided in patients with renal failure
Cough

Question 18

What are the effects of at-1 receptor blockers and examples

Answer 18

They block the binding of angiotensin 2 to at-1 receptors which prevents the maladaptive changes
Helps to maintain the beneficial effects of angiotensin 2 at at-2 receptors
Losartan

Question 19

How do diuretics work ?

Answer 19

Increase rate of urinary excretion
Increase salt and water excretion
Decreases EDV so reduces symptoms of oedema and improves exercise capacity

Question 20

What are the 2 types of diuretics ?

Answer 20

Loop diuretics - furosemide and bumetanide
- inhibit sodium reabsorption on ascending limb
Non- potassium sparing - chlorothiazide
Potassium sparing- amiloride, spironolactone- aldosterone antagonists

Question 21

Which duiretic are used when ?

Answer 21

Severe congestion - loop diuretic s

Mild oedema- diuretics that work on distal tubules

Question 22

What are the adverse effects of diuretics ?

Answer 22

Volume depletion- dehydration
Postural hypotension
Hypokalemia - non potassium sparing
Hyperkalemia - potassium sparing

Question 23

Why are cardiac glycosides used in hf ?

Answer 23

Rescue symptoms, improve exercise tolerance and reduce hospitalisation.
Acts to improve contractility of he heart

Question 24

What is the mechanism of action of cardiac glycosides ?

Answer 24

Increase force of contraction - inhibit sodium/potassium ATPase which increase intracellular sodium, by sodium calcium exchange it increases intracellular calcium which increases contraction.
Decrease sympathetic dive by sensitising baroreceptors

Question 25

How do vasodilators work on hf ?

Answer 25

Nitrates act as NO donors to cause vasodilation

Increase exercise capacity and decreases preload and after load