Drs Rebecca Knowles and Norma O’Flynn, and Professor Adam Timmis (left) discuss the role of GPs, who will be at the centre of medical management for stable angina
Angina is typically experienced as a constricting discomfort in the chest that is provoked by exertion or stress. It is the most common manifestation of coronary artery disease (CAD) and, unlike acute coronary syndromes, incidence of first-diagnosed angina is not diminishing in the UK.1 Angina is caused by myocardial ischaemia, in most cases as a consequence of obstructive CAD.2 Treatments to correct ischaemia, either with anti-anginal drugs or coronary revascularisation, are effective in relieving symptoms.3 However, angina in the community is not a benign disorder3 and requires lifestyle modification, particularly smoking cessation and exercise, coupled with secondary prevention drugs to improve long-term prognosis.2
Need for the guideline
The recently published NICE Clinical Guideline (CG) 126 on Management of stable angina2 makes recommendations that are applicable to the care of adults (18 years and over) who have a diagnosis of stable angina as a result of atherosclerotic disease. For recommendations on diagnosis of stable angina, reference should be made to NICE CG95 on Chest pain of recent onset.4
Angina is a chronic condition that is managed across the primary and secondary care sectors. Its treatment embraces a range of lifestyle, pharmacological, intravascular, and surgical interventions, but there has been little agreement about their relative efficacy or the extent to which they should be applied in individual patients. Revascularisation procedures, for example, are still carried out on many patients who have not first received optimal medical therapy;5 many patients continue to smoke, unaware of the help available in specialist clinics. In some cases, symptoms persist despite the best efforts of healthcare professionals, and this has led to the introduction of treatments of doubtful efficacy that have never been properly assessed. These treatments include transcutaneous electrical nerve stimulation, enhanced external counterpulsation, and acupuncture for which reliable evidence was not found in the guideline literature search.2
The most important role of the NICE guideline is to provide a framework for effective, evidence-based treatment that can be applied equitably to people with angina. Patients recognise the potential threat posed by a diagnosis of stable angina and will be helped by the emphasis in the guideline on provision of advice, information, and support from clinicians, and on the need to address common misconceptions. Many people with a diagnosis of stable angina believe that all activities should be severely curtailed and that a heart attack or death is imminent. However the reality is that angina symptoms can be relieved, normal activities resumed, and heart attack and death prevented by applying the guideline's recommendations.
Management of stable angina in primary care
The optimal management of stable angina, recommended by NICE in CG126, involves appropriate lifestyle advice and a two-pronged pharmacological strategy, which is readily applied in primary care.2 The quick reference guide includes a care pathway on managing angina (see Figure 1).6
The GP should address issues according to the individual needs of those with stable angina. These may include:2
- self-management skills—the patient should be advised to pace activities and set goals for himself/herself
- concerns about the possible impact of stress, anxiety, or depression on angina—this should involve advice about physical exertion, including sexual activity.
People should not be excluded from treatment based on their age alone, nor should investigations or treatment of symptoms differ based on gender or ethnic group. Individuals should be informed that there is no evidence of benefit for stable angina from vitamins or fish oil.
The NICE guideline on the management of angina recommends that:2
- all people with stable angina should be given a short-acting nitrate and be instructed in its use and be made aware of any possible side-effects
- first-line anti-anginal treatment is with a beta blocker or a calcium-channel blocker, substituting one for the other or combining both if symptoms persist—when using a calcium-channel blocker with a beta blocker, a dihydropyridine calcium-channel blocker is recommended; for example, slow-release nifedipine, amlodipine, or felodipine
- monotherapy with a long-acting nitrate or one of a range of newer drugs, including ivabradine, nicorandil, and ranolazine, is recommended for patients unable to tolerate the first-line drugs
- a third anti-anginal drug should only be considered if symptoms are not satisfactorily controlled with two anti-anginal drugs and the person is waiting for revascularisation or revascularisation is not considered appropriate or acceptable.
If symptoms are controlled by optimal medical treatment
It is important for the primary care physician to emphasise to those individuals whose anginal symptoms are controlled when receiving optimal medical management that angioplasty and stenting does not further improve cardiovascular outcomes. These people therefore usually have little to gain from specialist cardiological referral. Some of them however, despite being symptom-free, may have high-risk coronary anatomy, defined by complex three-vessel or left main stem disease, and there is evidence that bypass surgery can improve prognosis in this situation.7 High-risk anatomy is only present in a small proportion of cases, but patients need to be properly informed of this possibility because those who are prepared to accept surgery, despite the absence of symptoms, will need specialist referral for exclusion of this high-risk condition.
People with stable angina should receive balanced information and have the opportunity to discuss the benefits, limitations, and risks of continuing drug treatment, coronary artery bypass graft (CABG), and percutaneous coronary intervention (PCI) to help them make an informed decision about their treatment. Information that needs to be discussed with asymptomatic patients who are on optimal medical treatment includes:2
- their prognosis without further investigation
- what the chances are of them having left main stem or three-vessel disease
- whether CABG is available to improve the prognosis in a subgroup of people with left main stem or proximal three-vessel disease
- the process and risks of investigation
- any benefits and risks of CABG and what potential survival gain there might be.7
Primary care physicians who do not feel confident in providing this information should ensure that patients are referred to see a specialist at least once so that this important conversation can be held.
If symptoms are not controlled despite optimal medical treatment
Patients who remain symptomatic after optimal medical treatment require specialist cardiological referral for consideration of revascularisation by PCI or CABG, depending largely on the findings at cardiac catheterisation. The NICE guideline emphasises the importance of discussion of these findings by a multidisciplinary team, including cardiac surgeons and interventional cardiologists, so that the risks and benefits of continuing drug treatment or revascularisation by CABG or PCI, can be properly considered.
Drugs for secondary prevention of angina
The NICE CG126 guideline makes recommendations on drugs for secondary prevention of cardiovascular disease in line with its other published guidelines:2
- statin treatment (simvastatin 40 mg or 80 mg is recommended) with the aim of achieving targets for cholesterol and low-density lipoprotein cholesterol of <4 mmol/l and <2 mmol/l, respectively, if possible8
- aspirin (75 mg/day for people with stable angina) is recommended for all people who do not have contraindications for its use (and with regard to any co-morbidities or risk of bleeding)
- angiotensin-converting enzyme (ACE) inhibitors should be considered for patients with stable angina and diabetes—ACE inhibitors should be continued in patients receiving them for hypertension in line with NICE CG127.9
Clopidogrel does not have a licence for use in stable angina.
|Figure 1: Care pathway for stable angina6|
When revascularisation with CABG or PCI is appropriate, explain to the patient that:2
- the main purpose is to improve the symptoms of stable angina
- CABG and PCI are effective in relieving symptoms of angina
- it may be necessary to repeat revascularisation after either CABG or PCI—the rate is lower after CABG
- stroke is an uncommon complication after CABG or PCI—the incidence is similar after either procedure
- some people with multivessel disease may have a potential survival advantage after CABG.
Primary care physicians and commissioners of services will find CG126 particularly helpful because it is clear in indicating the lack of evidence for interventions such as vitamin therapy, transcutaneous electrical nerve stimulation, and enhanced external counterpulsation, emphasising instead lifestyle modification, such as smoking cessation and exercise, and optimal medical therapy as the mainstays of treatment. The guideline puts general practice firmly at the centre of angina management and, once the diagnosis has been established (usually in the chest pain clinic) it can be the GP who supervises ongoing medical management.
Patients should be referred back for further cardiological assessment and consideration of revascularisation if symptoms fail to respond to treatment. Adherence to specific secondary prevention drugs and attention to factors such as blood pressure control, smoking cessation, and lifestyle measures are key to long-term outcomes for patients with stable angina.
NICE has developed the following tools to support implementation of Clinical Guideline 126 on Management of stable angina. The tools are now available to download from the NICE website: www.nice.org.uk/CG126
Baseline assessment tool
The baseline assessment tool is an Excel spreadsheet that can be used by organisations to identify if they are in line with practice recommended in NICE guidance and to help them plan activity that will help them meet the recommendations.
Clinical audit tool
Audit tools aim to assist organisations with the audit process, thereby helping to ensure that practice is in line with the NICE recommendations. They consist of audit criteria and data collection tool(s) and can be edited or adapted for local use.
The costing statement estimates the financial impact to the NHS of implementing this clinical guideline. This statement focuses on the financial impact of the recommendations that require most change in resources to implement in England.*
This is an interactive algorithm that brings together NICE guidance on chest pain of recent onset, unstable angina and non-ST-segment-elevation myocardial infarction, and stable angina.
The factsheet provides details of the Guideline Development Group considerations and rationale underpinning the recommendations on revascularisation and signposts some of the sources of evidence used in developing the recommendations.
The slides provide a framework for discussing the NICE guideline with a variety of audiences and can assist in local dissemination. This information does not supersede or replace the guidance itself.
|*NICE Clinical Guideline 126 is unlikely to have a significant cost impact for the NHS at a national level; however, local circumstances may vary, which could incur costs or generate savings at a local level.|
- The NICE guideline sets out a clear algorithm on the management of stable angina, which can be included in local care pathways
- Commissioners should link this guideline to that covering the assessment of chest pain of recent onset (CG954) and the use of new technologies, such as computed tomography angiography
- There is no absolute need for specialist referral to establish a diagnosis of stable angina, but this is often required to identify high-risk coronary anatomy
- The QOF still offers points for specialist referral for angina (CHD 13) even though this is not always necessary
- Commissioners should ensure provision of optimal medical management for patients with stable angina in primary care and consider use of local audits to check implementation
- Local formularies should identify pharmacological options for medical management, which are available generically and at low-acquisition costs
- Commissioners should ensure that contracts with providers of specialist cardiology services define when angiography and stenting should and should not occur in line with the NICE guideline
- angiography (one or two stents) = £3676
- cardiology outpatients = £214 (new), £108 (follow up).
- Lampe F, Morris R, Walker M et al. Trends in rates of different forms of diagnosed coronary heart disease, 1978 to 2000: prospective, population based study of British men. BMJ 2005; 330 (7499): 1046–1050.
- National Institute for Health and Care Excellence. Management of stable angina. Clinical Guideline 126 (a partial update of TA73). London: NICE, 2011. Available at: www.nice.org.uk/guidance/CG126
- Buckley B, Murphy A. Do patients with angina alone have a more benign prognosis than patients with a history of acute myocardial infarction, revascularisation or both? Findings from a community cohort study. Heart 2009; 95 (6): 461–467.
- National Institute for Health and Care Excellence. Chest pain of recent onset: assessment and diagnosis of recent onset chest pain or discomfort of suspected cardiac origin. Clinical Guideline 95 (a partial update of TA73). London: NICE, 2010. Available at: www.nice.org.uk/guidance/CG95
- Borden W, Redberg R, Mushlin A et al. Patterns and intensity of medical therapy in patients undergoing percutaneous coronary intervention. JAMA 2011; 305 (18): 1882–1889.
- National Institute for Health and Care Excellence. Management of stable angina (a partial update of TA73). Quick reference guide London: NICE, 2011. Available at: www.nice.org.uk/guidance/CG126
- Yusuf S, Zucker D, Peduzzi P et al. Effect of coronary artery bypass graft surgery on survival: overview of 10-year results from randomised trials by the Coronary Artery Bypass Graft Surgery Trialists Collaboration. Lancet 1994; 344 (8922): 563–570.
- National Institute for Health and Care Excellence. Lipid modification: cardiovascular risk assessment and the modification of blood lipids for the primary and secondary prevention of cardiovascular disease. Clinical Guideline 67. London: NICE, 2008 (reissued 2010). Available at: www.nice.org.uk/guidance/CG67
- National Institute for Health and Care Excellence. Hypertension: clinical management of primary hypertension in adults. Clinical Guideline 127 (partially updates and replaces CG34). London: NICE, 2011. Available at: www.nice.org.uk/guidance/CG127 G