Flashcards in Chronic Heart Failure Deck (40):
What is heart failure?
Impaired ability of the heart to function as a pump and maintain sufficient cardiac output to meet the demands of the body
What is the incidence of heart failure in the over 65s?
Estimated annual incidence of 10%
What is the 5-year prognosis of heart failure?
50% mortality within 5 years (NYHA class III/IV) - poor long-term outcome
What are the 3 main causes of heart failure? Can you name any other causes?
1. Ischaemic heart disease - developed world
2. Dilated cardiomyopahty
3. Hypertension - Africa
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)
Describe the 5 main pathophysiological mechanisms leading to heart failure
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
Name 5 risk factors that may aggravate or initiate heart failure by increasing myocardial work
Differentiate between the 3 clinical syndromes of heart failure
- ishaemic HD, valvular HD, HTN
- 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
What is the commonest cause of left ventricular systolic dysfunction?
Ischaemic heart disease
Define diastolic heart failure
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.
List 4 key symptoms associated with heart failure
1. Exertional dyspnoea
3. Paroxysmal nocturnal dyspnoea
List 10 signs you might expect to find on examination of a patient with heart failure
1. Displaced apex beat (cardiomegaly)
2. S3 and S4
3. Elevated JVP
6. Bi-basal lung crackles
7. Pleural effusion
8. Ankle oedema (+/- sacral)
10. Tender hepatomegaly
Name and outline the classification system for assessing severity of heart failure. What else does it predict?
New York Heart Association (NYHA) classification
- No limitation
- Mild limitation. Normal physical activity produces fatigue, dyspnoea or palpitations
- Marked limitation. Marked symptoms with gentle physical activity
- Symptoms occur at rest and exacerbated by any physical activity
Also predicts response to therapy.
List 4 key initial investigations indicated in a patient with symptoms and signs of heart failure?
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
- 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 (:
5. Cardiac catheterisation
6. Thallium perfusion imaging
7. PET scanning
8. Cardiac MRI
9. Dobutamine stress echo
In these patients revascularisation will improve LV function and long-term prognosis.
What is 'hibernating myocardium' and how can it be identified?
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.
List 5 radiological features you might see in a patient with signs and symptoms of heart failure
1. Cardiac enlargement
2. Hilar haziness
3. Kerley B lines
4. Upper lobe venous diversion
5. Fluid in right horizontal fissure
- Can be normal
List 6 blood tests you might order for a patient with signs and symptoms of heart failure
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
List 4 features might you expect to see on the ECG of a patient with heart failure
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
What general measures should be considered in the management of chronic heart failure? (7 in total)
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
- Pneumococcal disease and influenza
5. Correct aggravating factors
- Arrhythmias, anaemia, hypertension, pulmonary infections
- Symptomatic heart failure disqualifies driving large lorries and buses
7. Sexual activity
- Do not take PDE-5 inhibitors (e.g. sildenafil) if on nitrates
List the 7 key pharmacological agents used in the management of chronic heart failure
1. ACE inhibitor or ARA
- Perindopril, lisinopril, quinapril
- Losartan, ibersartan, candesartan
- Bisoprolol, carvediol, nebivolol
4. Spironolactone or eplerenone
- Isosorbide mononitrate plus hydralazine
7. Inotropic agents
Which drugs have been shown to improve the prognosis of chronic heart failure?
1. ACE inhibitor or A2RA
…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.
What are the main side-effects of ACE-inhibitors and what precautions should be taken?
1. 1st dose hypotension
2. Renal impairment (hyperkalaemia)
3. Dry cough
- 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)
In which patients are ACEI and ARA contraindicated? Name an alternative agent.
Patients with bilateral renal artery stenosis.
Isosorbide plus hydrazine is used in patients intolerant of ACEI and ARA.
Name the 3 classes of diuretics used in the management of chronic heart failure
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
What additional action do loop diuretics have when given intravenously?
Induce venodilatation independent of their diuretic effect
True or false: thiazide diuretics are preferred over loop diuretics in patients with poor renal function
False - thiazide diuretics are ineffective in patients with poor renal function (eGFR <30 mL/min)
How does metolazone act and when is its use indicated?
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).
State a common side-effect of spironolactone
Gynaecomastia or breast pain
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?
1. Spironolactone (or epleredone)
2. Loop diuretic, e.g. furosemide
3. Isosorbide dinitrate plus hydralazine
A patient with acute MI and heart failure is prescribed losartan and carvediol. What additional drug(s) should be added to optimise his regimen?
Eplerenone - reduces mortality in these patients.
When might the concomitant use of an ACEI and ARA be used and when is this combination contraindicated?
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 :
- Renal impairment
In which patients is digoxin indicated?
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
A patient with heart failure and fluid overload is prescribed ramipril and bisoprolol. What additional drug(s) should be added to optimise his regimen?
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)
What is the main concern when prescribing metolazone in combination with a loop or thiazide diuretic?
Profound diuresis can occur. Patient should therefore be monitored carefully to avoid dangerous electrolyte disturbances
Name 4 non-pharmacological options available for treatment of heart failure?
- 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
In which patients might revascularisation be indicated?
Patients with coronary artery disease
In which patients might biventricular pacing be indicated?
LVSD with moderate/severe symptoms and widened QRS
In which patients might an implantable cardioverter-defibrillator be indicated?
LVEF <30% on optimal medical therapy
In which patients might cardiac transplantation be indicated?
Younger patients with intractable HF
What are the 3 main causes of death in the first 5 years following cardiac transplantation?
1. Operative mortality
2. Organ rejection
3. Infection secondary to immunosuppressive treatment