Heart failure

Question 1

Define HF

Answer 1

clinical syndrome characterised by impaired cardiac pumping leading to the inability to pump blood and O2 to metabolising tissue despite normal filling pressures

Question 2

What is ejection fraction (EF)?

Answer 2

Amount of blood pumped by the heart in one contraction

Question 3

What is congestive HF?

Answer 3

HF with fluid retention/congestion

Question 4

What are the different classifications of HF?

Answer 4

Systolic -REF
Diastolic - PEF
Acute
Chronic

Question 5

Explain systolic -REF

Answer 5

• LVEF less than 35%

- LV can’t contract so heart can’t pump enough blood out therefore blood can not get in

Question 6

Explain Diastolic - PEF

Answer 6

• LVEF more than 50%

- LV cannot relax so heart can not fill with blood therefore blood can not get out

Question 7

What is acute HF

Answer 7

• rapid onset of sudden cardiac decline

- Life threatening

Question 8

what is chronic HF?

Answer 8

• slow/progressive cardiac decline

- usually due to chronic conditions such HPT and diabetes

Question 9

Describe the pathophysiological mechanisms of HF-REF.

Answer 9

• cardio renal - Forward failure causes water retention and reduced blood flow
• cardio circulatory - forward failure results in peripheral vasoconstriction and increased PVR
• neurohormonal activation and cardiac dysfunction results in reduced cardiac out and BP which increases SNS, RAAS and ADH this leads to cardiac remodelling

Question 10

Describe the effects of neurohormonal activation.

Answer 10

• activation of SNS increases HR, contractility and vasoconstriction - increased catecholamines leads to ischaemia and cardiac remodelling. the increased renin activates RAAS.
• RAAS activation increases Ang II which increases vasoconstriction, SNS activation and cardiac remodelling. it increases aldosterone which leads to water and Na+ retention
• increases ADH increases water retention and vasoconstriction

Question 11

What are the congestive symptoms of HF

Answer 11

Sacral/ankle oedema, productive cough, SOB/breathlessness and unable to lay flat

Question 12

what are the hypo perfusion symptoms of HF?

Answer 12

decreased exercise tolerance, cold hands and feet and fatigue

Question 13

What are the non-pharmacological treatments for chronic HF and state examples

Answer 13

Lifestyle modifications - increase activity to min 30mins a day, lose weight if needed, smoking cessation, alcohol moderation, decrease salt intake in diet, reduce fluid intake

Surgical - heart transplant.

Question 14

Describe the current drug management treatment pathway for chronic HF/HF-REF. Give examples of drugs

Answer 14

1. Diuretics e.g. Furosemide for water retention
2. 1st line - BBs and ACEI/ARB e.g. atenolol and lisinopril/candesartan
3. aldosterone -RA e.g. spironolactone
4. ARNI e.g. Sacubitril/Valsartan - must STOP ACEI/ARB
5. If channel inhibitor e.g. Ivabradine if resting HR > 75bpm
6. Vasodilator e.g. Hydralazine/ISDN - this FIRST LINE if patient intolerant to AECI/ARB
7. Inotropic agent e.g. digoxin

Question 15

What is the mechanism of actions of Diuretics e.g.furosemide?

Answer 15

inhibit Na+/K+ exchange in DCT to promote diuresis which decreases plasma volume.

arterial and venodilation reduces preload increasing exercise tolerance and decreasing congestive symptoms

Question 16

What are the adverse side effects of diuretics?

Answer 16

hyperkalaemia, hypercalcemia, hyperuricemia, hyperglycaemia, hyperlipidemia

Question 17

What is the mechanism of action of ACEIs?

Answer 17

inhibit Ang II and RAAS which decreases vasoconstriction, preload and afterload - decreasing contractility, HR and SNS activation - reducing cardiac remodelling

increases bradykinin increases vasodilation and reduces plasma volume

Decreases aldosterone which reduces water retention and congestive symptoms

Question 18

what are the adverse side effects of ACEIs?

Answer 18

Ang II - 1st dose hypotension, hyperkalaemia and worsening of renal function.

bradykinin - cough and angioedema

Question 19

What is the mechanism of action of BBs?

Answer 19

Antagonise effects of adrenaline and noradrenaline at B-adrenoceptors

inhibit neurohormonal activation to inhibit SNS activation and reduce HR

Question 20

what are the adverse side effects of BBs?

Answer 20

fluid retention, fatigue, bradycardia and hypotension

Question 21

What is the mechanism of action of Spironolactone and what are the side effects?

Answer 21

Block aldosterone-R to reduce aldosterone - decrease plasma volume and congestive symptoms

SEs - hyperkalaemia