VOL: 101, ISSUE: 07, PAGE NO: 28
Anne Lovell, RGN, is British Heart Foundation heart failure specialist nurse, at South Cambridgeshire PCT and Addenbrooke's NHS Trust, CambridgeHeart failure is the general term used to describe the syndrome where the heart is unable to provide an adequate supply of blood to the patient's tissues to meet their metabolic demands.
Heart failure is the general term used to describe the syndrome where the heart is unable to provide an adequate supply of blood to the patient's tissues to meet their metabolic demands.
The most common cause of heart failure in the UK is coronary artery disease, with many patients having had a myocardial infarction in the past (Petersen et al, 2002). A history of hypertension is also common, as is atrial fibrillation. Heart damage of unknown cause, such as dilated cardiomyopathy, accounts for just under 15 per cent of cases under the age of 75 (Fox et al, 2001).
Around 900,000 people in the UK have heart failure - with almost as many with damaged hearts but, as yet, no symptoms of heart failure (Petersen et al, 2002). Both the incidence and prevalence of heart failure increase steeply with age, with the average age at first diagnosis being 76 years (Cowie et al, 1999). While around one in 35 people aged 65-74 years has heart failure, this increases to about one in 15 of those aged 75-84 years, and to just over one in seven in those aged 85 years and above (Davies et al, 2001). The risk of heart failure is higher in men than in women in all age groups, but there are more women than men with heart failure due to population demographics (Petersen et al 2002).
Patients with heart failure may have a number of symptoms, the most common being breathlessness, fatigue, exercise intolerance and fluid retention (Badgett et al, 1996). The severity of their symptoms is graded using the New York Heart Association classification. Patients may move through the grades in both directions as their condition progresses or responds to treatment. However, these symptoms are not specific to heart failure and therefore diagnosis depends upon a combination of good clinical skills with history taking and physical examination supplemented by investigations. These should include a 12-lead ECG and echocardiography that requires interpretation by an experienced person who also has access to the patient's history, symptom profile, medication list and test results (Box 1).
Detailed recommendations are provided in the NICE guideline on the management of chronic heart failure (NICE, 2003) The aims of therapy in heart failure are to:
- Improve life expectancy;
- Improve quality of life.
The relative importance of these aims will vary between individual patients and should take into account patients' preferences and may change with time.
Treatment can be grouped into non-pharmacological and pharmacological measures. The former includes lifestyle measures and invasive procedures such as coronary revascularisation, cardiac resynchronisation therapy, ventricular assist devices, implantable cardioverter-defibrillators (ICD) and cardiac transplantation.
Inactivity can lead to physical deconditioning which, in turn, leads to worsening of symptoms and exercise performance. Training can improve exercise tolerance through adaptations to peripheral muscles without adversely affecting cardiac function (Lloyd-Williams et al, 2002).
Aerobic training such as walking and restrictive exercise (weight training) and breathing exercise training have all shown benefits in improving exercise performance and quality of life without damaging effects on central haemodynamics. (Lloyd-Williams et al, 2002).
The issue of nutritional advice is complicated and the emphasis shifts over the course of the disease. In the early stages, a low-fat, cardio-protective diet to help manage lipids, hypertension and particularly weight control is a priority. In the latter stages, an adequate calorie intake with least effort to eat and digest while also being appetising to the individual is paramount.
Patients with severe heart failure who may have mesenteric congestion due to fluid overload often suffer from reduced absorption of nutrients, constipation and loss of appetite. This, coupled with breathlessness at rest or with the effort of eating, can lead to malnutrition and even cachexia. Unfortunately, this is often masked by fluid retention, making assessment particularly difficult. The advice of a dietician is extremely valuable to ensure an adequate nutritional intake and often requires the use of dietary supplements.
Patients should be strongly advised not to smoke and alcohol intake, particularly of high-volume drinks such as beer, should be limited or stopped if the cause of the heart failure is found to be due to chronic excessive alcohol consumption.
The pharmacological treatment described here is specifically aimed at the management of heart failure due to left ventricular systolic dysfunction, the most common type. Drug treatment should be tailored to the individual patient and referral for more specialised advice should be considered where appropriate. In general, drug treatment to improve symptoms and exercise capacity, in particular loop diuretic drugs, will require adjustment over time according to patient response and changes in symptoms. Treatment to improve longevity and reduce hospitalisation rates, including angiotensin converting enzyme (ACE) inhibitors and beta-blockers, should be introduced and up-titrated to the dose proven to be effective in RCTs or at least the maximum tolerated dose.
ACE inhibitors are well established in the management of heart failure and asymptomatic left ventricular systolic dysfunction, although in practice the doses used are often found to be suboptimal.
Anxiety exists among health care professionals regarding the use of beta-blockers in heart failure because, until the mid-1990s, they were considered to be contraindicated due to their negative inotropic effect. However, there now exists overwhelming evidence that demonstrates their safety and effectiveness. Their introduction needs to be at an appropriate time when the patient is euvolaemic and their fluid balance is stable. An appropriate beta-blocker should be started at a low dose and titrated up slowly with close monitoring of symptoms and blood chemistry. Following commencement or increase in dose of a beta-blocker, patients often experience a transient increase in symptoms, which may require short-term adjustment of their diuretic and patients should always be warned of this.
Other drugs commonly used to manage heart failure include aldosterone antagonists, digoxin and angiotensin receptor blockers (ARBs). As coronary heart disease, hypertension and atrial fibrillation are often responsible for the development of heart failure, these conditions should be collectively managed. Clearly, when patients are prescribed so many drugs, the issues of concordance and drug interaction need to be considered, especially as many elderly patients will have coexisting diseases.
Changes in fluid balance can occur due to even slight increases in the workload of the heart, such as a cold or other infection, very hot weather conditions or changes in the heart rhythm, particularly tachyarrhythmia. People with heart failure can monitor their own condition very effectively if they have a good understanding of what to look out for.
Awareness of the early, often subtle, changes in their symptoms which may signify the beginning of fluid overload, coupled with prompt adjustment to their treatment, can prevent catastrophic deterioration that results in admission to hospital or even death. Patients and carers should be alert to shortness of breath, increasing peripheral oedema or symptoms of angina. An excellent way to detect very early signs of fluid retention is monitoring weight. Patients can do this at home using bathroom scales. They should weigh themselves first thing in the morning after passing urine but before eating or drinking. A weight gain of 1kg in any three-day period is likely to be fluid and can be managed by an adjustment to their diuretic dose. If the weight gain happens repeatedly, a change to their long-term treatment should be considered.
Unlike in cancer, the disease trajectory of heart failure is unpredictable (Teno, et al, 2001). Superimposed on a gradual deterioration, there is a high risk of sudden death, usually due to a fatal arrhythmia. This makes it difficult to predict the course of the disease and to know when and how to provide appropriate end-of-life care. There is substantial evidence for considerable unmet palliative needs of patients and informal carers in heart failure, in particular for symptom control, psychological and social support, planning for the future and end-of-life care (Anderson et al, 2001). General and specialist palliative care providers and heart failure services may benefit from working and learning together to provide care for this patient group.
The British Heart Foundation (BHF) has pioneered the BHF Nurse Project to provide expert cardiac nursing care in the community to support patients and families. This began in 1995, with 15 cardiac liaison nurses supporting post-MI patients. There are now 180 BHF heart nurses delivering patient care and support. BHF heart nurses are also responsible for training other health care professionals and many have been instrumental in initiating new services for patients.
For information about the BHF's Real Valentine appeal, visit the www.bhf.org.uk/realvalentine website. - This article has been double-blind peer-reviewed.
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