Chronic Heart Failure

Question 1

What is heart failure?

Answer 1

Impaired ability of the heart to function as a pump and maintain sufficient cardiac output to meet the demands of the body

Question 2

What is the incidence of heart failure in the over 65s?

Answer 2

Estimated annual incidence of 10%

Question 3

What is the 5-year prognosis of heart failure?

Answer 3

50% mortality within 5 years (NYHA class III/IV) - poor long-term outcome

Question 4

What are the 3 main causes of heart failure? Can you name any other causes?

Answer 4

Main causes:

1. Ischaemic heart disease - developed world
2. Dilated cardiomyopahty
3. Hypertension - Africa

Other causes:

1. Cardiomyopathy (hypertrophic, restrictive)
2. Valvular heart disease (mitral, aortic, tricuspid)
3. Congenital heart disease (atrial septal defect, ventricular septal defect)
4. Alcohol and chemotherapy, e.g. imatanib, doxorubicin
5. Hyperdynamic circulation (anaemia, pregnancy, thyrotoxicosis, Paget’s disease)
6. Right heart failure (RV infarct, pulmonary hypertension, pulmonary embolism, cor pulmonale, COPD)
7. Arrhythmias (severe bradycardia or tachycardia)
8. Pericardial disease (constrictive pericarditis, pericardial effusion)
9. Infections (Chagas’ disease)

Question 5

Describe the 5 main pathophysiological mechanisms leading to heart failure

Answer 5

When the heart fails, compensatory mechanisms attempt to maintain CO and peripheral perfusion. However, mechanisms are eventually overwhelmed and become pathophysiological.

1. Sympathetic NS
   - arteriolar constriction increases afterload
2. Renin-angiotensin system
   - salt and H2O retention leads to oedema and dyspnoea
   - angiotensin II increases afterload via arteriolar constriction
3. Natriuretic peptides
   - ANP, BNP, C-type peptide
   - diuretic, natriuretic and hypotensivee (reduce preload and afterload)
4. Ventricular dilatation
   - compensatory effects of dilatation become limited by flattened contour of Starling’s curve
   - Increased venous pressure contributes to pulmonary and peripheral oedema
   - as ventricular diameter increases, myocardial O2 requirements increase
5. Ventricular remodelling
   - hypertrophy, loss of myocytes and interstitial fibrosis lead to irreversible contractile failure

Question 6

Name 5 risk factors that may aggravate or initiate heart failure by increasing myocardial work

Answer 6

1. Arrhythmias
2. Anaemia
3. Hyperthyroidism
4. Pregnancy
5. Obesity

Question 7

Differentiate between the 3 clinical syndromes of heart failure

Answer 7

1. LVSD
   - ishaemic HD, valvular HD, HTN
2. RVSD
   - secondary to LVSD
   - pulmonary HTN, RV infarction, adult congenital HD
3. Diastolic heart failure
   - normal LVEF (above 45-50%)
   - echo: abnormal LV relaxation and filling +/- LVH
   - decreased CO due to impaired filling

Question 8

What is the commonest cause of left ventricular systolic dysfunction?

Answer 8

Ischaemic heart disease

Question 9

Define diastolic heart failure

Answer 9

A clinical syndrome in which patients have:
1. Symptoms and signs of HF
2. Normal or near normal LV systolic function
3. Normal LV chamber size
4. Evidence of LV diastolic dysfunction (eg, abnormal LV filling and/or elevated filling pressures)
DHF is a major cause of HF with preserved ejection fraction.

Question 10

List 4 key symptoms associated with heart failure

Answer 10

1. Exertional dyspnoea
2. Orthopnoea
3. Paroxysmal nocturnal dyspnoea
4. Fatigue

Question 11

List 10 signs you might expect to find on examination of a patient with heart failure

Answer 11

1. Displaced apex beat (cardiomegaly)
2. S3 and S4
3. Elevated JVP
4. Tachycardia
5. Hypotension
6. Bi-basal lung crackles
7. Pleural effusion
8. Ankle oedema (+/- sacral)
9. Ascites
10. Tender hepatomegaly

Question 12

Name and outline the classification system for assessing severity of heart failure. What else does it predict?

Answer 12

New York Heart Association (NYHA) classification
Class I
- No limitation
Class II
- Mild limitation. Normal physical activity produces fatigue, dyspnoea or palpitations
Class III
- Marked limitation. Marked symptoms with gentle physical activity
Class IV
- Symptoms occur at rest and exacerbated by any physical activity

Also predicts response to therapy.

Question 13

List 4 key initial investigations indicated in a patient with symptoms and signs of heart failure?

Answer 13

1st line Ix:

1. Chest X-ray
   - Cardiac enlargement
   - Features of LV failure: hilar haziness and Kerley B lines (pulmonary oedema), upper lobe venous diversion, fluid in right horizontal fissure
   - Can be normal
2. ECG
   - Evidence of underlying causes: arrhythmias, ischaemia, LVH in HTN
3. Blood tests
   - FBC: anaemia
   - LFT: hepatic congestion
   - Glucose: diabetes
   - U&E: baseline for diuretics and ACE-I
   - Thyroid function: elderly, AF
   - BNP: normal (:
4. Cardiac catheterisation
5. Thallium perfusion imaging
6. PET scanning
7. Cardiac MRI
8. Dobutamine stress echo

In these patients revascularisation will improve LV function and long-term prognosis.

Question 14

What is ‘hibernating myocardium’ and how can it be identified?

Answer 14

Hibernating myocardium = a region of impaired myocardial contractility due to persistently impaired coronary blood flow.

Echocardiography: A wall motion abnormality at rest which improves during a low-dose dobutamine stress test is classified as “hibernating myocardium”. Low dose dobutamine stimulates contractile function and thus helps to predict functional recovery after revascularisation.

Question 15

List 5 radiological features you might see in a patient with signs and symptoms of heart failure

Answer 15

1. Cardiac enlargement
2. Hilar haziness
3. Kerley B lines
4. Upper lobe venous diversion
5. Fluid in right horizontal fissure
   - Can be normal

Question 16

List 6 blood tests you might order for a patient with signs and symptoms of heart failure

Answer 16

1. FBC: anaemia
2. LFT: hepatic congestion
3. Glucose: diabetes
4. U&E: baseline for diuretics & ACE-I
5. Thyroid function: elderly, AF
6. BNP or NTproBNP: normal (BNP <100mg/ml) excludes heart failure

Question 17

List 4 features might you expect to see on the ECG of a patient with heart failure

Answer 17

1. Arrhythmias
2. Ischaemic heart disease
3. Right and left ventricular hypertrophy
4. Presence of conduction delay or abnormalities (e.g. LBBB)

A normal ECG virtually excludes left ventricular systolic dysfunction

Question 18

What general measures should be considered in the management of chronic heart failure? (7 in total)

Answer 18

1. Education
2. Physical activity
   - Encourage low-level (20-30 min walk, 3-5 times a week)
3. Diet and social
   - Weight reduction
   - No added salt diet
   - Avoid alcohol (negative inotrope)
   - Stop smoking
4. Vaccinate
   - Pneumococcal disease and influenza
5. Correct aggravating factors
   - Arrhythmias, anaemia, hypertension, pulmonary infections
6. Driving
   - Symptomatic heart failure disqualifies driving large lorries and buses
7. Sexual activity
   - Do not take PDE-5 inhibitors (e.g. sildenafil) if on nitrates

Question 19

List the 7 key pharmacological agents used in the management of chronic heart failure

Answer 19

1. ACE inhibitor or ARA
   - Perindopril, lisinopril, quinapril
   - Losartan, ibersartan, candesartan
2. Beta-blocker
   - Bisoprolol, carvediol, nebivolol
3. Diuretic
4. Spironolactone or eplerenone
5. Digoxin
6. Vasodilators
   - Isosorbide mononitrate plus hydralazine
7. Inotropic agents

Question 20

Which drugs have been shown to improve the prognosis of chronic heart failure?

Answer 20

1. ACE inhibitor or A2RA
2. Beta-blocker
   …given to all patients with HF due to LV dysfunction
3. Spironolactone improves survival in combination with conventional Rx in patients with moderate/severe HF.
4. Eplerenone reduces mortality in patients with acute MI and heart failure.

Question 21

What are the main side-effects of ACE-inhibitors and what precautions should be taken?

Answer 21

1. 1st dose hypotension
2. Renal impairment (hyperkalaemia)
3. Dry cough
4. Angioedema

• Introduce gradually with low initial dose and titrate up every 2 days
• Regular BP monitoring
• Check serum potassium and renal function (creatinine levels normally rise by about 10-15% during therapy)

Question 22

In which patients are ACEI and ARA contraindicated? Name an alternative agent.

Answer 22

Patients with bilateral renal artery stenosis.

Isosorbide plus hydrazine is used in patients intolerant of ACEI and ARA.

Question 23

Name the 3 classes of diuretics used in the management of chronic heart failure

Answer 23

1. Loop diuretics
   - Furosemide (20-40 mg daily; max 250-500 mg), bemetanide
2. Thiazide diuretics
   - Bendroflumethiazide (2.5 mg daily; max 10 mg), metolazone
3. Aldosterone antagonists
   - Spironolactone (25 mg daily), eplerenone

Question 24

What additional action do loop diuretics have when given intravenously?

Answer 24

Induce venodilatation independent of their diuretic effect

Question 25

True or false: thiazide diuretics are preferred over loop diuretics in patients with poor renal function

Answer 25

False - thiazide diuretics are ineffective in patients with poor renal function (eGFR <30 mL/min)

Question 26

How does metolazone act and when is its use indicated?

Answer 26

Thiazide diuretic - inhibits sodium reabsorption in distal renal tubule. Causes a profound diuresis - only used in severe and resistant heart failure (combined with loop diuretic).

Question 27

State a common side-effect of spironolactone

Answer 27

Gynaecomastia or breast pain

Question 28

A patient with severe chronic heart failure is prescribed lisinopril and bisoprolol but remains symptomatic. What additional drug(s) could be added to optimise his regimen?

Answer 28

1. Spironolactone (or epleredone) 2. Loop diuretic, e.g. furosemide 3. Isosorbide dinitrate plus hydralazine

Question 29

A patient with acute MI and heart failure is prescribed losartan and carvediol. What additional drug(s) should be added to optimise his regimen?

Answer 29

Eplerenone - reduces mortality in these patients.

Question 30

When might the concomitant use of an ACEI and ARA be used and when is this combination contraindicated?

Answer 30

Candesartan or valsartan may be given under specialist supervision as adjuncts to an ACE inhibitor when other treatments are unsuitable. The concomitant use of this combination, together with an aldosterone antagonist or a potassium-sparing diuretic is not recommended due to increased risk of : - Hyperkalaemia - Hypotension - Renal impairment

Question 31

In which patients is digoxin indicated?

Answer 31

1. Patients with heart failure and AF 2. Add-on therapy in patients in sinus rhythm who remain symptomatic despite standard treatment, i.e. - ACEI + BB - In combination with either an aldosterone antagonist, ARA, or isosorbide dinitrate with hydrazine

Question 32

A patient with heart failure and fluid overload is prescribed ramipril and bisoprolol. What additional drug(s) should be added to optimise his regimen?

Answer 32

1. Either a loop or a thiazide diuretic - Thiazide if good renal function - Loop if poor renal function 2. If insufficient, combine loop and thiazide 3. Consider addition of metolazone (usually combined with loop)

Question 33

What is the main concern when prescribing metolazone in combination with a loop or thiazide diuretic?

Answer 33

Profound diuresis can occur. Patient should therefore be monitored carefully to avoid dangerous electrolyte disturbances

Question 34

Name 4 non-pharmacological options available for treatment of heart failure?

Answer 34

1. Revascularisation - CAD - Improves RWMA in 1/3rd 2. Cardiac resynchronisation therapy - Aka 'biventricular pacing' - LVSD with moderate/severe symptoms and widened QRS 3. Implantable cardioverter-defibrillator (ICD) - LVEF <30% on optimal medical therapy - Reduce risk of sudden death from ventricular tachyarrhythmias 4. Cardiac transplantation - Younger patients with intractable HF - 90% 1-year survival; 75% at 5 years

Question 35

In which patients might revascularisation be indicated?

Answer 35

Patients with coronary artery disease

Question 36

In which patients might biventricular pacing be indicated?

Answer 36

LVSD with moderate/severe symptoms and widened QRS

Question 37

In which patients might an implantable cardioverter-defibrillator be indicated?

Answer 37

LVEF <30% on optimal medical therapy

Question 38

In which patients might cardiac transplantation be indicated?

Answer 38

Younger patients with intractable HF

Question 39

What are the 3 main causes of death in the first 5 years following cardiac transplantation?

Answer 39

1. Operative mortality 2. Organ rejection 3. Infection secondary to immunosuppressive treatment

Question 40

What is the main threat to health after the first 5 years following cardiac transplantation?

Answer 40

Accelerated coronary atherosclerosis