SPECIALTY : CARDIOLOGY CLINICAL PROBLEM: HEART FAILURE

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1 SPECIALTY : CARDIOLOGY CLINICAL PROBLEM: HEART FAILURE Summary Heart failure has a worse prognosis than many cancers with an annual mortality of 40% in the first year following diagnosis and 10% thereafter. Accurate and timely diagnosis is therefore important and echocardiography is mandatory. CAUSES OF HEART FAILURE Common causes of heart failure are Coronary heart disease and myocardial infarction (most common cause). Hypertension. Valvular heart disease These conditions generally cause left ventricular systolic dysfunction although hypertension can cause diastolic heart failure while mitral stenosis is usually associated with normal left ventricular function. Other causes of left ventricular systolic dysfunction include alcoholic cardiomyopathy, dilated cardiomyopathy and myocarditis. Heart failure can also be secondary to diseases that are not typically associated with left ventricular systolic dysfunction and examples are pericardial disease, hypertrophic cardiomyopathy and infilterative disorders such as amyloidosis and sarcoidosis. The reason for making a distinction between heart failure due to left ventricular systolic dysfunction and other types is that there are differences in treatment. The pharmacological recommendations in the NICE guidelines are directed at patients with left ventricular systolic dysfunction and patients with other types of heart failure should be seen and assessed by cardiologists. Symptoms The most common symptoms are Breathlessness Fatigue Exercise intolerance Peripheral oedema SYMPTOMS AND SIGNS OF HEART FAILURE St. Richard s Hospital Unfortunately, these symptoms are not unique to heart failure and are frequently seen in patients presenting to primary care. Other conditions which may present with some or all of these symptoms include obesity, chest disease, venous insufficiency, drug induced ankle swelling (e.g. calcium antagonists) or fluid retention (e.g. NSAIDs), hypoalbuminaemia and renal or hepatic disease. Other symptoms of heart failure include nocturia, anorexia, abdominal bloating and discomfort, constipation, and cerebral symptoms such as confusion, dizziness and memory impairment. Signs

2 Raised JVP (high predictive value but may not be present especially if patient on diuretics) Gallop rhythm Displaced apex Peripheral oedema As with the symptoms, the signs are not unique to heart failure but generally, the more symptoms and signs that are present, the more confident that a diagnosis of heart failure can be made. However, investigations are required to confirm the diagnosis. THE DIAGNOSIS OF HEART FAILURE If a detailed history and clinical examination suggests a diagnosis of heart failure, then confirmatory investigations are required (Figure 1). In one study, less than half the patients treated for heart failure in general practice had the disease. A normal ECG is very reassuring and we can be 98% sure that a patient does not have heart failure. Measurement of serum BNP (brain natriuretic peptide) has been introduced recently and can also be used to help diagnose heart failure. A negative result is useful in excluding heart failure. It can be seen that a normal ECG and a negative BNP result can be used to exclude heart failure this means referral for echocardiography maybe more selective and should be taken into consideration when investigating the patient. However, BNP assays are expensive and factors such as the ready availability of echocardiography should be considered. Locally, the waiting time for open access echocardiography is 2 3 weeks, therefore at present we are not advocating BNP. Echocardiography is extremely useful for the assessment of the structure and function of the heart and its valves. Sometimes, the quality of the images is suboptimal and alternative imaging techniques are required. HEART FAILURE? History and Examination Request Investigations ECG, Chest X-Ray, Blood Tests Start Diuretics if clinically indicated If investigations abnormal/indicative of heart failure REQUEST ECHO. Direct Referral to Echo Service For Routine Investigation Refer to Cardiology clinic for specialist opinion and echo if: Severe symptoms Heart Murmur The diagnosis is still unclear There is complex concomitant disease There is severe left ventricular dysfunction The patient may be considered a suitable candidate for transplant THE TREATMENT OF HEART FAILURE

3 This section deals with the treatment of patients with left ventricular systolic dysfunction. Diuretics. These are used for the relief of congestive symptoms and fluid retention (figure1) Loop diuretics such as frusemide are commonly used while thiazides such as bendrofluazide and metolazone can be added (often temporarily) to increase diuresis. Dosage is titrated against symptoms and body weight and serum electrolytes need to be monitored. Combination or high dose diuretics increase the risk of hypokalaemia and renal impairment. ACE inhibitors. All patients should be considered for treatment with ACE inhibitors, which should be started before beta-blockers. Treatment should be initiated at the relevant low dose and the dose increased at 2 weekly intervals so long as biochemistry, blood pressure and side effects allow. In hospital, where there is close monitoring, dosages can be increased daily. Examples of target dosages that have been used in clinical trials are Captopril 50 mg tds, Enalapril 20mg bd, Lisinopril 30mg od and Ramipril 10mg od. For other ACE inhibitors, the target doses are based on manufacturers recommendations rather than from outcome studies. Care and close supervision are required before initiating ACE inhibitors in patients with a serum creatinine > 200µmol/l or a potassium > 5.0mmol/l or a systolic blood pressure < 80mmHg. An increase in creatinine of up to 50% above baseline, or to 200 µmol/l, whichever is the smaller, is acceptable as is an increase in potassium to 5.9 mmol/l. Beta Blockers. The beta blockers licensed for heart failure are bisoprolol and carvedilol and these should be initiated after ACE inhibitors regardless of whether the patient is symptomatic or not. The rule is start low, go slow and heart rate, blood pressure and clinical status should be checked before each dose increase. If patients were already on a beta-blocker prior to developing heart failure, it is acceptable to continue with the existing beta-blocker.(nurse led Heart Failure Clinic) Spironolactone. Patients who remain moderately symptomatic and who are already on diuretics, ACE inhibitors and beta blockers can be commenced on Spironolactone at a dose of 25mg od. It is important to closely monitor the serum potassium and creatinine levels. Digoxin. This should be considered in anyone with atrial fibrillation or in those with severe heart failure despite the above treatment. (usualy introduced by specialist) Other drugs. The majority of patients will have coronary heart disease and may require other drugs such as aspirin and statins. Warfarin should be considered in those with atrial fibrillation and those assessed as being at risk for left ventricular thrombus formation. Calcium antagonists that are negatively inotropic should be avoided but amlodipine can be used. Angiotensin II receptor antagonists are not licensed for heart failure but can be used if patients are intolerant of ACE inhibitors. Heart Failure Nurse Specialist. Patients with heart failure are often on sub-optimal treatment. For instance, it is estimated that as few as 10% of patients are on betablockers. Two hospital heart failure nurse specialists are based on Charlton Ward, St. Richard s Hospital. Heart failure nurse specialists have been shown to reduce hospital admission rates by educating patients about their condition and by giving timely management advice when their clinic status is deteriorating. Lifestyle. Patients should be advised to give up smoking and patients with alcoholic cardiomyopathy should abstain from drinking. Regular aerobic and resistive exercise can improve symptoms and exercise tolerance. Overweight patients should lose weight aiming for a BMI of 25 to 30. Vaccination. Annual vaccination against influenza is recommended as is vaccination against pneumococcal disease (required once). Cardiac Resynchronisation Therapy. Biventricular pacemakers have been shown in some studies to improve symptoms and to reduce hospitalisations for heart failure. Pending studies investigating their effect on long-term survival, NICE has

4 made no firm recommendations about their prescription. Current indications are those patients with left ventricular ejection fraction 35%, drug refractory symptoms and a QRS duration > 120ms. Implantable cardioverter-defibrillators (ICDs). Up to 50% of heart failure patients die suddenly from cardiac arrest rather than from pump failure. ICDs are recommended for those who have survived a cardiac arrest due to VT or VF or who have had sustained VT that was haemodynamically significant 5. Figure 1. Algorithm for the pharmacological treatment of symptomatic heart failure due to left ventricular systolic dysfunction (from NICE guidelines for the management of chronic heart failure). Generalist New diagnosis Add Diuretic Diurectic therapy is likely to be required to control congestive symptoms and fluid retention Start ACE inhibitor and titrate upwards Or if ACE inhibitor not tolerated (eg due to severe cough) Consider angiotensin-ll receptor antagonist Specialist input Add Digoxin If a patient in sinus rhythm remains symptomatic despite therapy with a diurectic, ACE inhibitor (or angiotensin in receptor antagonist) and beta blocker. OR if a patient is in atrial fibrillation then use as first line therapy Add beta-blocker and titrate upwards Add spironolactone If patient remains moderately to severely symptomatic despite optimal drug therapy listed above Seek specialist advice for further options Specialist REFERRAL TO A CARDIOLOGIST Referral to a cardiologist should be considered in the following circumstances When there is a cardiac murmur indicating valvular heart disease or other lesion.

5 For assessment of any underlying coronary heart disease especially if angina is poorly controlled. When heart failure is difficult to manage e.g. requiring high dose diuretics or patient is intolerant of medication. When the cause of heart failure is other than left ventricular systolic dysfunction e.g. diastolic heart failure, restrictive cardiomyopathy and pericardial disease. If patients are suitable candidates for cardiac transplantation, cardiac resynchronisation therapy or implantable cardioverter-defibrillators. If patients have significant co-morbidity. PALLIATIVE CARE Palliative care has been a relatively neglected part of the management of patients with heart failure. The main areas of need include Symptom control. Psychological and social support. o Intensive Care at Home o Recently established Heart Support Group Planning for the future End of life care General palliative care can be delivered by the usual professional carers but specialist advice may be required from professionals with palliative care skills. REFERENCES Davie AP et al. Value of the electrocardiogram in identifying heart failure due to left ventricular systolic dysfunction. BMJ 1996;312:222 Hobbs FDR et al. Reliability of N-terminal pro-brain natriuretic peptide assay in diagnosis of heart failure:cohort study in representative and high risk community populations. BMJ 2002;324:1-5 Developing services for heart failure. Department of Health Publications. Chronic heart failure. Management of chronic heart failure in adults in primary and secondary care. Clinical Guideline 5. National Institute for Clinical Excellence. Guidance on the use of implantable cardioverter defibrillators for arrhythmias. NICE Technology Appraisal Guidance No AUTHOR: Dr Yuk-ki Wong, Consultant Cardiologist, St Richard s Hospital, Chichester. OTHERS INVOLVED: Consensus reached by Consultant Physician Colleagues Dr Colin Reid and Dr Conrad Murphy, Dietetics Department, & CCU at St Richard's Hospital, The Royal West Sussex Trust, Chichester. All LRMG Committee. PUBLISHED: 7/97 REVIEWED & UPDATED: 04/00, 06/04, 12/07 NEXT REVIEW: 12/09