Guidelines for treatment of Cardiac failure

Heart failure is not a diagnosis but a pathophysiological syndrome with many possible aetiologies.

Diagnosis

Diagnosis is based on a combination of symptoms and signs of objective evidence of cardiac dysunction.

Symptoms

Patients typically complain of exertional breathlessness and/or fatigue.

Clinical findings:

Note: these signs may be difficult to elicit and none of them is specific. The commonest are raised jugular venous pressure with or without oedema. If heart failure is suspected, investigate.

  1. Establish the underlying cause. Signs of heart failure may be caused by: ischaemic heart disease, hypertension, valve disease, congestive cardiomyopathy, pericardial disease.

  2. A precipitating cause must be sought (myocardial infarction, arrhythmia, infection, anaemia, pulmonary disease, thyrotoxicosis, adverse drug effect).

Investigations:

All patients should have:

  1. ECG - Systolic left ventricular dysfunction is very unlikely if normal

  2. Chest X-ray

  3. Hb, U&E's

  4. Echocardiography

  5. Thyroid function test

Treatment:

All patients should be encouraged, when appropriate to reduce the intake of salt, alcohol and calories.

Chronic heart failure (CHF)

  1. Control of excessive salt and water retention. Diuretics

    1. Loop : Bumetanide or Furosemide

Bumetanide may be better absorbed than furosemide in the presence of heart failure.

Bumetanide 1 mg = furosemide 40 mg.

Caution: close monitoring of electrolytes is essential when metolazone is used.

The three classes of diuretics have different sites of action and their effects are additive. Combinations are more effective than single agents and are valuable when the fluid retention is refractory to treatment. Close monitoring of electrolytes is essential when combinations are used. A potassium-sparing diuretic is more effective than potassium supplementation.

Spironolactone 25mg daily (increased to 50mg if necessary) was found to reduce mortality by 30% in the RALES study, in patients with NYHA class 4 heart failure who were already receiving an ACE inhibitor and loop diuretic. Nausea and gynaecomastia is a common side effects.

  1. Vasodilators

    1. ACE inhibitors

    2. Nitrates

    3. Hydralazine

  2. Inotropes

    1. Digoxin

    1. Dopamine, dobutamine

  3. Betablocker (See guidelines for initiation below)

ACE inhibitors reduce mortality in CHF and an attempt should be made to establish every eligible patient on a drug from this group except those whose primary problem is an arrhythmia or valvular stenosis. Formulary ACE inhibitors are: captopril, lisinopril and ramipril.

Treatment should always be initiated with a small test dose e.g. captopril 6.25mg. The aim should then be to increase the dosage to the maximum tolerated.

Special care is required in the presence of:

  1. Dehydration

  2. Creatinine equal or greater than 200 micromol/l,

  3. Serum potassium greater than 5.5 mmol/l,

  4. Standing systolic blood pressure less than 100mmHg,

  5. Furosemide dosage equal to or greater than 80mg or the equivalent. If diuretic dosage is high, dehydration is suspected or there is systolic hypotension consider discontinuing diuretics for 24-36 hours, before commencing ACE inhibitor.

Consider discontinuing potassium-sparing diuretic/supplement before starting an ACE inhibitor in view of possible hyperkalaemia.

If ACE inhibitors are not tolerated an angiotensin II blocker should be substituted (candesartan is preferred).

Guidelines for initiation of b-blockers

Bisoprolol is given once daily, and is supported by evidence from the CIBIS-II trial.

Carvedilol is given twice daily, is supported by evidence from several trials but is more expensive than bisoprolol.

  1. Weight and renal function should have been stable for 4 weeks and the dosage of ACE inhibitor and diuretic unchanged.

  2. Dosage to be doubled at 2 weekly intervals in the absence of adverse events up to target dosage.

  3. Patients must be advised that minor weight gain and breathlessness is common initially.

  4. Staff or patients to contact heart failure clinic on 291 2752.

Digoxin is especially useful in atrial fibrillation but there is now evidence, especially in chronic heart failure, for its use in patients in sinus rhythm.

Intravenous inotropes may be appropriate in the short-term for some patients with otherwise intractable cardiac failure.

Correctable causes should always be sought and treated, eg surgery for valvular heart disease. Patients aged <60 years may be potential candidates for cardiac transplantation.

Anticoagulants should be used in all patients with atrial fibrillation and considered in those with significantly dilated hearts, especially in the presence of mitral valve disease.

Acute Heart Failure

This is a medical emergency usually resulting from acute myocardial infarction or hypertension.

  1. The patient should be nursed sitting up

  2. Give 100% oxygen by face mask at 8 - 10 L/min

  3. Intravenous Furosemide - Doses of 40-80mg may be given over 3-5mins. Larger doses at a rate not exceeding 4mg/min

  4. Diamorphine 2.5mg followed by 2.5mg five minutes later if necessary I.V. This will produce vasodilation and reduce patient distress.

  5. Sublingual GTN will reduce preload by venodilation. This should be followed by intravenous nitrates, care being taken to keep fluid volume to a minimum. Alternatively or subsequently a nitrate patch or oral nitrate may be used.

  6. Digitalise, especially in the presence of atrial fibrillation

Precipitating causes must be sought and treated. If there is no prompt improvement, and the aetiology is not clearly established, echocardiography should be requested and specialist advice sought.