Four guidelines covering aspects of coronary heart disease (CHD) and one on the prevention of cardiovascular disease (CVD) were published by SIGN in February 2007. They contain important recommendations that are likely to have a significant impact on general practice.1–5
This group of documents has been systematically developed from the clinical evidence and has also taken into consideration issues of cost-effectiveness. Some of the key recommendations relevant to general practice will not only have a powerful influence on how patients are managed, but will also help to make the case for additional resources to improve their care.
The guideline on risk estimation and the prevention of CVD1 highlights how Framingham risk scores underestimate the risk in populations with high CHD mortality rates and that social deprivation should be included in any estimation of risk in these groups of people.
The guideline has followed the JBS2 advice to treat all those with a CVD risk of ≥20% over 10 years as high risk,6 but acknowledges that the evidence supporting the decision to lower the threshold is not clear.1 It also points out that current clinical evidence does not demonstrate that lipid-lowering therapy should be titrated to achieve proposed targets for low density lipoprotein cholesterol levels.1 Therefore, GPs should continue to target the currently recommended total cholesterol level of <5 mmol/l in individuals with existing CVD.
This assessment of the evidence is good news for general practice, as it will now be very difficult for the current QOF quality targets to be driven lower. For patients with established CVD and a systolic blood pressure >140 mmHg and/or diastolic blood pressure >90mmHg, there is a strong recommendation for them to be considered for therapy to lower blood pressure levels.
Clear guidance is given within the acute coronary syndrome (ACS) guideline on the use of antiplatelet therapy.2 All GPs need to be aware that patients presenting with ACS and ischaemic changes on electrocardiogram (ECG) should be treated immediately with not only 300 mg aspirin but also with 300 mg clopidogrel. Low-dose combination therapy (aspirin 75 mg and clopidogrel 75 mg) should be continued for up to 4 weeks in ST elevation ACS, and for 3 months in non-ST elevation ACS. The latter conflicts with the cost-effectiveness advice from NICE,7 which recommends treatment for up to 12 months, but the SIGN guideline group did not feel that there was likely to be a constant relative risk reduction across all time periods. Table 3 accompanying the guideline points out the large number of patients who need to be treated beyond 3 months in order to prevent a further event.
When compared with thrombolysis, the benefits of primary percutaneous intervention for the immediate treatment of ST elevation ACS are not in doubt. However, implementation of this approach is likely to result in a significant change in organisation of the immediate care of ACS patients.
In patients with symptoms and signs of chronic heart failure (CHF), the heart failure guideline suggests that a chest X-ray should be part of the initial examination, with measurement of brain natriuretic peptide (BNP) central to further diagnosis, although this procedure is not always available.3 A low BNP and normal ECG excludes the diagnosis of CHF, whereas a raised BNP or abnormal ECG makes this a possibility, and an echocardiogram is required, again with service implications.
Angiotensin-converting enzyme (ACE) inhibitors and beta-blockers remain the main treatment option in all patients with CHF resulting from left ventricular dysfunction (LVD).
Multidisciplinary follow-up, including pharmacy input, is the ideal approach, and the use of nurses specially trained in the care of patients with heart failure, who are able to alter diuretic doses after discharge, should be considered.
In well tolerated atrial fibrillation, the guideline on cardiac arrthymias in CHD makes it clear that rate control, in preference to rhythm control, is the recommended strategy to reduce morbidity and prevent hospitalisation.4 Ventricular rate should be controlled with a beta-blocker, rate-limiting calcium channel blocker, or digoxin. As heart rate during exercise is not effectively controlled by digoxin, such therapy should only be used as a first-line treatment if the patient is sedentary or in overt heart failure.
The guideline on the management of stable angina recommends that patients with suspected angina should be referred to the local chest pain evaluation service that offers the earliest appointment.5
A baseline ECG and exercise tolerance test remain the initial investigations of choice, with myocardial perfusion scintigraphy being considered for those with pre-existing ECG abnormalities, or for those unable to exercise.
An important recommendation based on recently published evidence is that all patients with stable angina including those without LVD or previous ACS should be considered for treatment with an ACE inhibitor.8
As with all guidelines, the challenge is now to achieve full implementation of the recommendations. Grading of the evidence and recommendations allows targets to be set at attainable levels, bearing in mind possible workload constraints. It is hoped that a coordinated approach in Scotland, including the use of directly enhanced services, will prove successful in the long term.
- Scottish Intercollegiate Guidelines Network (SIGN 97) Risk estimation and the prevention of cardiovascular disease. A national clinical guideline. Edinburgh: SIGN, 2007.
- Scottish Intercollegiate Guidelines Network (SIGN 93) Acute coronary syndromes. A national clinical guideline. Edinburgh: SIGN, 2007.
- Scottish Intercollegiate Guidelines Network (SIGN 95) Management of chronic heart failure. A national clinical guideline. Edinburgh: SIGN, 2007.
- Scottish Intercollegiate Guidelines Network (SIGN 94) Cardiac arrhythmias in coronary heart disease. A national clinical guideline. Edinburgh: SIGN, 2007.
- Scottish Intercollegiate Guidelines Network (SIGN 96) Management of stable angina. A national clinical guideline. Edinburgh: SIGN, 2007.
- JBS 2: Joint British Societies' guidelines on prevention of cardiovascular disease in clinical practice. Heart 2005; 91 (suppl 5): v1–52.
- National Institute for Clinical Excellence. Clopidogrel in the treatment of non-ST-segment-elevation acute coronary syndrome. Technology appraisal 80. London: NICE, 2004.
- Dagenais G, Pogue J, Fox K et al. Angiotensin-converting-enzyme inhibitors in stable vascular disease without left ventricular systolic dysfunction or heart failure: a combined analysis of three trials. Lancet 2006; 368 (9535): 581–588G