The Scottish Intercollegiate Guidelines Network (SIGN) has recently published an updated guideline for the management of stable angina (SIGN 96).1 Stable angina, also known as chronic angina, is a facet of coronary heart disease (CHD), and typically occurs on exertion. It is quickly relieved by medication or rest. Patients with stable angina are at increased risk of myocardial infarction (MI) and premature death.2 Targeting these patients with effective treatments is an important component of their management, along with educating them on lifestyle interventions.
Management of stable angina
With the introduction of the GMS contract and the implementation of Quality Outcome Framework (QOF) points,3 GPs' time is becoming subject to increasing degrees of performance management. The management of CHD is also affected by this. The CHD indicators, which can be viewed here, show what is expected from each practice in order to qualify for QOF points.
Recommendations on diagnosis
There are a number of recommendations in the guideline to assist GPs in the diagnosis of stable angina. An initial diagnosis can be made within primary care but this should be supported by further assessment and risk stratification, which will normally require specialist input.1 The SIGN guideline is very helpful in this respect by detailing diagnosis, clinical assessments, and risk factors associated with increased risk of angina. Risk factors in individual patients include smoking, hypertension, diabetes, family history of CHD, and raised levels of cholesterol and other lipids.
The guideline indicates that a patient suspected of having angina should undergo a detailed clinical assessment, which should include:
- history and examination
- blood pressure measurement
- haemoglobin level testing
- assessment of thyroid function measurement of cholesterol and fasting blood glucose levels.
If symptoms persist, other factors should be considered. These include the following:
- body mass index or waist circumference
- murmur evaluation
- presence of depression or feelings of social isolation
- levels of physical activity
Clinical assessment should be followed by a baseline electrocardiogram (ECG) and an exercise tolerance test (ETT). Patients who are unable to undergo ETT or who have pre-existing ECG abnormalities should be considered for myocardial perfusion scintigraphy. Any high-risk patients would then be candidates for coronary angiography.
There are two main reasons to begin treatment for angina: to prevent MI, and to reduce the severity of symptoms. The recommended drug treatments for angina are as follows:
- sublingual glyceryl trinitrate tablets or spray for immediate relief of angina, or before beginning exercise likely to induce an attack
- beta blockers as first-line therapy for relief of symptoms
- rate-limiting calcium channel blockers, long-acting nitrates, or nicorandil—for patients who cannot tolerate a beta blocker
- if adequate control of symptoms is not achieved with a beta blocker, a calcium channel blocker should be added—if symptoms are still not controlled with maximum therapeutic doses, patients should be referred to a cardiologist
- all patients with stable angina should be receiving long-term standard aspirin and statin therapy
- two recent meta-analyses showed that angiotensin-converting enzyme (ACE) inhibitors significantly reduced all-cause and cardiovascular mortality4—all patients with stable angina should be considered for treatment with an ACE inhibitor, especially if they show signs of hypertension or left ventricular failure
- the question as to whether patients with stable angina, but without left ventricular systolic dysfunction, benefit from treatment with ACE inhibitors is controversial.5,6
It should not be forgotten that, for GPs, medical treatment is only one aspect of the spectrum. We should also be aiming to educate patients so that they can implement lifestyle changes and assume more responsibility for their own health.
Depression and coronary heart disease
The impact of CHD on a patient's mental state is highlighted in SIGN 96. It is known that depression is a significant factor in influencing mortality and morbidity associated with CHD, and it has been suggested that depression is equally as important as any other risk factor. The QOF targets include two screening questions for depression in patients with CHD, which are as follows:1
a)'During the last month, have you often been feeling down, depressed or hopeless?'
b)'During the last month, have you often been bothered by having little interest or pleasure in doing things?'
These questions should be addressed at the systematic review of the patient.
Coronary heart disease will increase in prevalence as the population ages. Effective treatment is available and, along with lifestyle modifications, GPs can expect improved symptom control and quality of life for patients.
Partnerships between GPs and their patients in the management of stable angina aim to recognise the patient's beliefs and wishes. Unfortunately, the GMS contract threatens to disturb the drive towards achieving such partnerships; linking concordance with medication to income introduces a risk that patient expectation with regard to management may assume less significance.
While SIGN 96 reiterates the principles of assessment, diagnosis, and pharmacotherapy, importantly, it also highlights the critical role of the patient.
- Scottish Intercollegiate Guidelines Network (SIGN 96). Management of stable angina. A national clinical guideline. Edinburgh: SIGN, 2007.
- Bunch T, Muhlestein J, Bair T et al; Intermountain Heart Collaborative Study Group. Effect of beta-blocker therapy on mortality rates and future myocardial infarction rates in patients with coronary artery disease but no history of myocardial infarction or congestive heart failure. Am J Cardiol 2005; 95 (7): 827–831.
- British Medical Association. Revisions to the GMS Contract, 2006/07. Delivering Investment in General Practice. London: BMA, 2006.
- 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): 581–588.
- Fox K; EURopean trial On reduction of cardiac events with Perindopril in stable coronary Artery disease investigators. Efficacy of perindopril in reduction of cardiovascular events among patients with stable coronary artery disease: randomised, double-blind, placebo-controlled, multicentre trial (the EUROPA study). Lancet 2003; 362 (9386): 782–788.
- Braunwald E, Domanski M, Fowler S et al; PEACE Trial Investigators. Angiotensin-converting-enzyme inhibition in stable coronary artery disease. N Engl J Med 2004; 351 (20): 2058–2068.G