Cardiac Failure

Question 1

What is systolic HF?

Answer 1

Impaired contractility/ejection

Question 2

What is diastolic HF?

Answer 2

Impaired filling/relaxation

Question 3

How is HF based on VLEF defined?

Answer 3

• Reduced EF (systolic) - LVEF < 40%
• Mid-range EF - LVEF 40-49%
• Preserved EF (diastolic) > 50%

Question 4

What are the symptoms of NYHA Class I?

Answer 4

• No symptoms

- Can do ordinary activities without limitations

Question 5

What are the symptoms of NYHA Class II?

Answer 5

• Mild symptoms
• Occasional swelling
• Limited exercise
• No symptoms @ rest

Question 6

What are the symptoms of NYHA Class III?

Answer 6

• Noticeable limitations in exercise

- Comfortable only @ rest

Question 7

What are the symptoms of NYHA Class IV?

Answer 7

• Unable to do any physical activity without discomfort

- Symptoms @ rest

Question 8

What mechanisms maintain pump function?

Answer 8

1. Cellular systems
   - myocardial hypertrophy to increase mass of contractile tissue
   = eccentric remodelling of heart > worsens loading condition of heart, perpetuates low CO
2. Frank-starling law
   - stroke vol + contractile force increased due to increased preload or LV end systolic pressure
3. Activation of neurohormonal systems
   - increased HR, force of contraction + preload
   a) SNS = increased contractility, vasoconstriction
   b) RAAS = reduced renal perfusion = salt-water retention, thirst, sympathetic stimulation, vasoconstriction
   c) Vasopressin activation

Question 9

What is the effect of vasopressin activation?

Answer 9

Reduced systemic BP = central baroreceptors = stimulation hypothalamus to produce vasopressin (ADH) = released by pituitary = vasoconstriction + water retention = increased systemic BP

Question 10

Describe the vicious cycle of HF?

Answer 10

LV dysfunction > decreased CO + BP = frank-starling, remodelling, neurohormonal activation > increased CO + BP > increased cardiac workload > LV dysfunction …

Question 11

What are the effects of salt + water retention?

Answer 11

ST: augments preload
LT: pulmonary congestion

Question 12

What are the effects of vasoconstriction?

Answer 12

ST: maintains BP for perfusion
LT: Exacerbated pump dysfunction (excessive afterload), increases cardiac energy expenditure

Question 13

What are the effects of sympathetic stimulation?

Answer 13

ST: increases HR + ejection fraction
LT: increases energy expenditure

Question 14

How is HF diagnosed?

Answer 14

• Blood tests - natiuretic peptides (BNP)
• ECG
• CXR - cardiomegaly, pleural effusions
• Echo
• Cardiac magnetic resonance

Question 15

What are the symptoms of HF?

Answer 15

• Dyspnoea
• Orthopnoea
• Pulmonary oedema
• Chest pain/ pressure
• Fragile/ weakness
• Nocturia/ oliguria
• Anorexia/ weight loss

Question 16

What are the signs of HF?

Answer 16

• Jugular venous distension
• Rales/ wheezing
• S3 gallop
• Ascites/ hepatomegaly
• Cyanosis
• Palpitations/ tachycardia
• Rapid weak pulse