Primary percutaneous coronary intervention for STEMI improves outcomes if it can be delivered in time, says Dr Alan Begg
|NICE Clinical Guideline 167 on Myocardial infarction with ST-segment elevation has been awarded the NICE Accreditation Mark.
This Mark identifies the most robustly produced guidance available. See evidence.nhs.uk/accreditation for further details.
P rimary percutaneous coronary intervention for STEMI improves outcomes if it can be delivered in time, says Dr Alan Begg
The British Heart Foundation (BHF) public education programme on the need to summon immediate ambulance assistance by dialing 999 when a person develops severe chest pain, which is likely to be a heart attack, has been very successful in recent years.1 Speed is of the essence in re-establishing the blood flow when a coronary artery is obstructed with thrombus, causing an acute ST-segment-elevation myocardial infarction (STEMI). In the first hour after occlusion of the artery, nearly 50% of heart muscle that could be salvaged is lost, and two-thirds is lost within 3 hours.2
The need for prompt action results in less of a role for primary care healthcare professionals in the management of an acute STEMI, apart from those working in rural areas. Patients with chest pain do, however, still present to the practice and the out-of-hours service, so it is important that GPs maintain their skills in resuscitation and familiarity with electrocardiography, and are aware of the evidence guiding the management of acute STEMI.
Primary percutaneous coronary intervention
NICE Clinical Guideline 167 (CG167) (www.nice.org.uk/CG167) on the acute management of myocardial infarction with ST-segment elevation was published in July 2013 and addresses reperfusion therapy through the use of either fibrinolysis, or primary percutaneous coronary intervention (PCI). 2
Publication of the National service framework for coronary heart disease (CHD) resulted in the development of a comprehensive system in England for using fibrinolysis as a means to restore coronary blood flow. 3 However, the main disadvantages of fibrinolysis are that it is not suitable for every patient because of:2
- possible bleeding complications
- frequent failure to produce reperfusion
- 1% of cases resulting in haemorrhagic stroke.
Clinical Guideline 167 accepts that mechanically restoring the blood supply using primary PCI should become the treatment of choice, on the basis of reduced mortality and improved outcomes with this procedure compared with fibrinolysis, provided primary PCI can be delivered in a timely fashion.2
Primary PCI is more expensive to deliver than fibrinolysis but is more clinically and cost effective than fibrinolysis if delivered within an appropriate time frame.4 The National Infarct Angioplasty project concluded, however, that although national provision of primary PCI is feasible, it is logistically challenging in some less densely populated parts of the country.4 The recommendations in NICE CG167 are important to consider for those involved in commissioning, especially if a service for primary PCI has yet to be established.
Prompt delivery of interventions
The time to reperfusion is all-important in the management of STEMI. Coronary reperfusion therapy (either primary PCI or fibrinolysis, as appropriate) should be delivered as quickly as possible for eligible people with acute STEMI. The guideline recommends primary PCI as the preferred strategy if:2
- the patient presents within 12 hours of the onset of symptoms and
- it can be delivered within 120 minutes of the time when fibrinolysis could have been given.
For patients presenting more than 12 hours after the onset of symptoms, primary PCI should be considered if there is evidence of continuing myocardial ischaemia.2
The time parameters used may cause confusion, as the Department of Health states acceptable performance measures for a primary PCI service to be:4
- 120 minutes from the time the patient calls for medical help to the time when an angioplasty balloon is first inflated, or coronary perfusion is confirmed on angiography (the ‘call to balloon time’) and
- 90 minutes from the time the patient arrives in hospital, to delivery of the intervention (the ‘door to balloon time’).
Radial versus femoral approach
The guideline also recommends that the operator performing primary PCI should consider a radial rather than femoral access.2 A meta-analysis has shown that radial access reduced major bleeding by 73% compared with femoral access (0.05% vs 2.3% p <0.001), and that there was also a trend for reductions in major adverse cardiac events and death using radial access. Using the radial approach also reduced hospital stays by 0.4 days.5 As a result of the radial approach being used, GPs are likely to see less significant groin-bruising and fewer haematomas than they do at present.
The use of primary PCI results in shorter in-patient stays compared with fibrinolysis (3 to 5 days vs. 5 to 9 days), and so patients return to primary care sooner.4 Once the patient has been discharged, general practice will have to ensure that preventative medical therapies are optimised and continued long term, cardiac rehabilitation is organised, and risk factors are corrected.
Clinical Guideline 167 has incorporated guidance from NICE Technology Appraisal 236 on the use of ticagrelor, in combination with low dose aspirin, as an alternative treatment to clopidogrel, for up to 12 months in people with a STEMI.6 Ticagrelor is a clinically more effective antiplatelet agent than clopidogrel and its use is cost effective.2,6
Clinical Guideline 167 indicates that the key issue for commissioners considering a primary PCI service is that outcomes for patients with STEMI:2
- are strongly related to how quickly primary PCI can be delivered
- may be influenced by the number of procedures carried out by the centre providing primary PCI.
Primary PCI requires a cardiac catheter laboratory and highly trained staff to be available 24 hours a day, 7 days a week, and it is debatable whether such a service can be provided in a medium-sized district general hospital as opposed to a regional specialised heart attack centre.7 It is important to take into account journey times, and to consider geography, road networks, and existing services (ambulance, community fibrinolysis, presence of a full-time, fully staffed and equipped primary PCI facility elsewhere).
Although primary PCI is more acceptable to patients than fibrinolysis, they may find initially that they are not being treated in their local hospital; and patients usually prefer local care.
The NICE guideline on the acute management of STEMI has the most relevance for commissioners in areas without a primary PCI service, but also for GPs in rural areas, who may need to continue to provide community fibrinolysis for the immediate future.
NICE implementation tools
NICE has developed the following tools to support implementation of Clinical Guideline 167 (CG167) on Myocardial infarction with ST-segment elevation. The tools are now available to download from the NICE website:
NICE support for commissioners
Costing reports are estimates of the national cost impact arising from implementation based on assumptions about current practice, and predictions of how it might change following implementation of the guideline.
A costing template helps services in estimating the local cost of implementing guidelines and public health guidance. This template allows individual NHS organisations and local health economies to quickly assess the impact guidance will have on local budgets.
NICE support for service improvement systems and audit
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
Clinical 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.
Key to NICE implementation icons
NICE support for commissioners
- Support package for commissioners and others for quality standards
- NICE guide for commissioners
- NICE cost impact support for guidance (selection from national report/local template/costing statement, dependent on topic)
NICE support for service improvement systems and audit
- Forward planner
- 'How to' guides (generic advice on processes)
- Local government briefings (with Centre for Public Health Excellence)
- Baseline assessment tool for guidance
- Audit support including electronic data collection tools
- E-learning modules (commissioned)
NICE support for education and learning
- Clinical case scenarios
- Learning packages including slide sets
- Shared learning and other local best practice examples
- NICE CG167 recommends primary PCI as a first-line treatment for STEMI so commissioners need to assess the feasibility of providing primary PCI locally
- Deciding where 24-hour-day, 7-day-a-week PCI centres are based is a decision to be made between the CCGs and Specialist Clinical Networks
- CCGs should ascertain whether their geography prevents some patients receiving primary PCI within the recommended time-limits and whether alternative fibrinolysis services need to be commissioned
- CCGs should ensure there are clear local pathways agreed between primary care, secondary care and ambulance services for suspected STEMI
- Tariff costs:a
- for actual or suspected myocardial infarction £3420 (EB10Z)
- for percutaneous intervention (1â€"2 stents) non-elective £3710 (EA31Z)
PCI=percutaneous coronary intervention; STEMI=ST-segment-elevation myocardial infarction; CCG=clinical commissioning group
- British Heart Foundation website. Heart attack. www.bhf.org.uk/heart-health/conditions/heart-attack.aspx (accessed 23 September 2013).
- NICE. Myocardial infarction with ST-segment elevation: the acute management of myocardial infarction with ST-segment elevation. Clinical Guideline 167. London: NICE, 2012. Available at: www.nice.org.uk/CG167
- Department of Health. National service framework for coronary heart disease.
DH, 2000. Available at: www.gov.uk/government/uploads/system/uploads/attachment_data/
- Department of Health vascular programme team. Treatment of heart attack national guidance. Final report of the National Infarct Angioplasty Project (NIAP). DH, 2008. Available at: www.bcis.org.uk/resources/documents/NIAP%20Final%20Report.pdf
- Jolly S, Amlani S, Hamon M et al. Radial versus femoral access for coronary angiography or intervention and the impact on major bleeding and ischemic events: a systematic review and meta-analysis of randomized trials. Am Heart J 2009; 157 (1): 132–140.
- NICE. Ticagrelor for the treatment of acute coronary syndromes. Technology Appraisal 236. London: NICE, 2011. Available at: www.nice.org.uk/TA236
- Whittaker A, Rowell L. Primary angioplasty for acute STEMI in secondary care: feasibility, outcomes and potential advantages. Br J Cardiol 2013; 20: 32–37.G