Diastolic dysfunction rx

Diastolic dysfunction: rx

Pretest

Question 1

Drugs used in heart failure may include:

1. angiotensin converting enzyme

inhibitor

2. a beta blocker such as carvedilol, bisoprolol, or metoprolol

3. angiotensin II receptor blocker valsartan

4. Digoxin has an important role in the symptomatic treatment of patients with heart failure and atrial fibrillation.

Keyword

Treatment

·                 Heart failure is characterised by neurohormonal activation that initially helps to maintain circulatory function but is ultimately harmful to the heart.

·                 Modern treatment aims to control symptoms and prolong life by blocking the neurohormonal activation and controlling the fluid retention.

·                 Lifestyle changes can have an important impact. Ready to cook meals and convenience foods contain large amounts of salt and may increase the dose of diuretic needed to control fluid retention.

·                 All patients should be discouraged from adding salt to their food and should try to reduce the amount of salt they add during cooking.

·                 Severe salt restriction (<2 g/day) is rarely necessary.

·                 Regular aerobic exercise should be encouraged, as it improves peripheral muscle function and exercise tolerance in patients with heart failure.

·                 Annual vaccination against influenza is a sensible precaution.

·                 If alcohol is the cause of the heart failure then abstinence is essential.

·                 Smoking cessation should be encouraged.

Drugs

·                 Diuretics are the most effective means of removing fluid retention, and their introduction often produces rapid symptomatic relief.

·                 Most patients with heart failure need at least a small dose of regular diuretic.

·                 On its own such treatment exacerbates neurohormonal activation, and modern treatment of heart failure due to systolic dysfunction of the left ventricle thus demands the use of two other types of drug: an angiotensin converting enzyme inhibitor and a beta blocker.

·                 The angiotensin converting enzyme inhibitor should be introduced at a low dose and titrated upwards over several weeks to the doses shown to be effective in clinical trials, while symptoms, blood pressure, and renal function are monitored.

·                 This can be safely accomplished in primary care, provided the patient is not hypotensive or on high dose diuretic treatment.

·                 Once the patient is stable on this treatment a beta blocker such as carvedilol, bisoprolol, or metoprolol can be added again starting at a low dose and titrating upwards gradually over several weeks, with close supervision of the control of the heart failure syndrome.

·                 Until recently, beta blockers were considered to be contraindicated in heart failure, but recent trials have shown that they can markedly improve survival and are safe to introduce,w1-w3 provided a "start low, go slow" policy is used.

·                 This can be very labour intensive and may be best managed by a nurse specialist.

·                 The valsartan heart failure trial found that patients did not live longer if the angiotensin II receptor blocker valsartan was added to conventional treatment with an angiotensin converting enzyme inhibitor.

·                 However, this study did show a reduction in the risk of admission to hospital for worsening heart failure.

·                 Ongoing trials will help to clarify the role of this class of drugs, but current evidence indicates that they are no more effective than angiotensin converting enzyme inhibitors in reducing mortality in patients with heart failure due to left ventricular systolic dysfunction.

·                 Most doctors would, however, now consider using angiotensin II receptor blockers for patients who develop an intractable cough on angiotensin converting enzyme inhibitors, rather than the previously favoured combination of oral hydralazine and nitrate.

·                 Spironolactone at a dose of 25-50 mg once daily reduces mortality in patients with moderate or severe symptoms due to systolic heart failure. Its benefit in other patient groups is unclear.

·                 Digoxin has an important role in the symptomatic treatment of patients with heart failure and atrial fibrillation. There is no evidence, however, that digoxin improves survival in patients in sinus rhythm.

·                 It may reduce the risk of admission to hospital, but its toxicity has to be considered, especially in elderly patients.

·                 Patients with atrial fibrillation are particularly complicated and usually benefit from specialist assessment.

·                 Formal anticoagulation with warfarin should be considered in order to reduce the risk of thromboembolism.

·                 Drugs that interact with anti-failure drugs or increase fluid retention such as non-steroidal anti-inflammatory agents; diltiazem, verapamil, or short acting dihydropyridine calcium antagonists; lithium; and parenteral corticosteroids should be avoided.

·                 Tricyclic antidepressants may increase the risk of arrhythmia. It is essential to educate patients about their drug treatment and which over the counter medicines they should avoid.

Post test

Question 1

Drugs used in heart failure may include:

1. angiotensin converting enzyme inhibitor

2. a beta blocker such as carvedilol, bisoprolol, or metoprolol

3. angiotensin II receptor blocker valsartan

4. Digoxin has an important role in the symptomatic treatment of patients with heart failure and atrial fibrillation.

Answer:

TTTT

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