Risk prediction for angina will assist in its management, writes Dr Ahmet Fuat.
Angina is a common problem in primary care. It affects about two million people in the UK, with a recent study revealing a sharp rise in the rate of hospitalisation for angina and other chest pain.
While most patients with stable angina have low mortality, research suggests that the five-year risk of death, disabling stroke or myocardial infarction (MI) ranges from 4 per cent to 35 per cent, depending on whether a patient is at low or high risk.
A risk score for predicting secondary atherosclerotic events in patients with stable angina is now available.
The scoring system can help GPs manage and stratify patients according to their likely future prognosis.
It is the first method available to assess angina patients' overall risk, using 16 routinely available clinical variables such as age, left ventricular ejection fraction, diabetes and smoking status (see box below).
The scoring system was developed by a group of UK and European researchers on behalf of the ACTION trial investigators and looked at 7,311 patients with stable angina worldwide over five years. The risk score quantifies the combined risk of death from any cause, MI and disabling stroke.
However, the risk score did not seem to predict the incidence of angiography or revascularisation or what happened to the patient - death, MI or disabling stroke.
According to the NSF for CHD, patients with suspected angina should be referred to a rapid-access chest pain clinic and assessed within a maximum of two weeks.
The NSF for CHD says that people with angina should be offered investigation and treatment to relieve their pain and reduce the risk of coronary events.
Three classes of drugs have traditionally been used to treat angina symptoms: beta-blockers, calcium-channel blockers and nitrates.
Beta-blockers are used as first-line treatment because they may improve survival.
There have been a number of comparisons between different classes of anti-anginal agents in terms of symptom reduction, but there is little evidence that one is superior to another.
Ivabradine is a selective sinus node inhibitor that is indicated in the treatment of chronic stable angina pectoris, with normal sinus rhythm in patients who cannot tolerate or have a contraindication to beta-blockers.
Patients with angina should also be offered treatment for the secondary prevention of coronary events, according to the new Joint British Societies' guidelines, published in December 2005.
The European Society of Cardiology issued new guidelines for the management of stable angina on 1 June 2006.
- Dr Fuat is a GP in Darlington, Yorkshire, and a member of the Primary Care Cardiovascular Society
PREDICTORS OF HIGHER-RISK ANGINA
- Poor exercise capacity with easily inducible ischaemia or a poor haemodynamic response to exercise.
- Impaired left ventricular function.
- Angina of recent onset.
- Previous MI.
- The number of coronary vessels with significant stenoses.
- British Heart Foundation Statistics 2005.
- Murphy N F et al. Reduced between-hospital variation in short term survival after acute MI: the result of improved cardiac care? Heart 2005; 91:726-30.
- Stewart S et al. The current cost of angina pectoris to the National Health Service in the UK. Heart 2003; 89: 848-53.
- North of England Evidence-Based Guideline Development Project. The primary care management of stable angina. Centre for Health Services Research, University of Newcastle upon Tyne, Report no 98.
- Clayton T C et al. Risk score for predicting death, MI and stroke in patients with stable angina, based on a large randomised trial cohort of patients. BMJ 2005; 331: 869.
- O'Toole L, Greech E D. Chronic stable angina: treatment options. BMJ 2003; 326: 1,185-8.
- DoH. The NSF for CHD, Department of Health, March 2005.
- Nidorf S M, Thompson P L, Jamorozik K D, et al. Reduced risk of death at 28 days in patients taking beta-blocker before admission to hospital with MI. BMJ 1990; 300: 71-4.
- JBS 2: Joint British Societies' guidelines on prevention of cardiovascular disease in clinical practice. Heart 2005; 91: v1-v2.