Heart Failure - Investigations And Management

Question 1

How to classify heart failure based on functional symptoms of the patient ?

Answer 1

1. Class 1 : no symptomatic limitation of physical activity
2. Class 11 : slight limitation of physical activity. Ordinary physical activity results in symptoms. No symptoms at rest.
3. Class 111: marked limitation of physical activity. Less than ordinary physical activity results in symptoms. No symptoms at rest.
4. Class 1V : inability to carry out any physical activity without symptoms. May have symptoms at rest. Discomfort increases with any degree of physical activity.

Question 2

What are 3 key questions you need to ask yourself,f when examining for heart failure ?

Answer 2

1. Does the patient even have heart failure ? Clinical and history examination. Differential diagnosis eg anaemia produces same symptoms.
2. What sort of heart failure does the patient have ?
3. What is causing heart failure ? Ischaemic heart disease. Hypertension ? Viral ? Alcohol ?

Question 3

How to investigate for heart failure ?

Answer 3

1. Full blood count : check for anaemia as the symptoms of anaemia are similar to heart failure. Anaemia can worsen heart failure as it puts further strain on the heart to meet the body’s demands. CRP levels ,
2. Electrolytes and renal function : renal function often deteriorates in heart failure.
3. MOST IMPORTANT : Brain natriuretic peptide ( NTPro - BNP ) - BNP is produced by the stretching of ventricles. It is produced to try and reduce blood pressure by increasing sodium loss and therefore increasing water loss. An elevated BNP suggests heart failure while a normal BNP with breathlessness usually excludes heart failure.
4. ECG - an abnormal ECG with raised BNP provides evidence for heart failures
5. CHEST X RAY : pulmonary oedema can be seen on a chest x ray. An enlarged heart can also be seen on a chest x ray as an increased cardiothoracic ratio ( close to 1:1).
6. Echocardiogram : can be used to measure the ejection fraction to help determine the type of heart failure. It can also assess the valve and ventricular function.
7. Coronary angiography : this technique allows for imaging of coronary arteries and can be used to determine if they are blocked an atherosclerotic plaque.

Question 4

How to manage acute heart failure ?

Answer 4

1. Must give oxygen : if hypoxic state
2. Must give an IV loop-diuretic Furosemide 80mg : this causes water loss to reduce the volume of fluid in circulation. This will reduce the after load and increase the cardiac output. This also helps to reduce oedema.
3. Also give anticoagulants : heparin to reduce the risk of venous clots forming.
4. The management may require additional ventilator support to help them breathe easier
5. and IV nitrates and IV morphine as a second line after furosemide. ( only made second line 6 years ago , used to be first line )

Question 5

How can chronic heart failure be managed by ?

Answer 5

1. Correcting the under,yin’s cause : heart transplant , mechanical assist device , pacemaker , implanted defibrillators
2. Non-pharmacological management : reduce salt intake , increase aerobic exercise , reduce alcohol intake
3. Pharmacological therapy : this is mainly for symptomatic improvement , to delay the progression of heart failure. For example ACEi , angiotensin receptor blockers ( used if bradykinin has a bad effect on patient). This prevents the action of angiotensin 11. , beta blockers ( reduce the heart rate ) , spironolactone ( aldosterone receptor antagonist), dieuretics. The aim of pharmalogical therapy is to reduce the after load and increase CO.

Question 6

Why when prescribing beta blockers you need to be careful ?

Answer 6

Because a failing myocardium may be dependant on heart rate. Therefore you need to initiate at a low dose. Titrations slowly.

Question 7

What are the physiological effects of beta blockers ?

Answer 7

Reduce heart rate

Reduce blood pressure ( as it reduces cardiac output )

Both of these effects reduce myocardial oxygen demand.

3. Reduce mobilisation of glycogen
4. Negative unwanted effects of catecholamines

Question 8

What is the peak time at which furosemide action is best ?

Answer 8

Peaks at 60-90 mins from when giving it , begins its action at 30 mins.

Question 9

What factor can triple BNP levels ?

Answer 9

AF

Question 10

What is an abnormal level of BNP ?

Answer 10

Above 2000 pg/ml

Question 11

For someone with good renal perfusion m good blood pressure would giving 40mg Furosemide have the same effect as giving that person 80mg Furosemide ?

Answer 11

Yes , it will have the same effect

Question 12

For someone with renal failure , do you give more or less furosemide ?

Answer 12

MORE - however not too much as people with renal failure will take longer to clear flurosemide so are at greater risk of intoxicicty.

Question 13

How to monitor someone on furosemide ?

Answer 13

HR

BP

RR

PO2

Fluid balance

Hourly urine output

Daily weight loss ( aim is for 1kg weight loss per day )