This guideline updates and replaces 'MI – secondary prevention' (NICE clinical guideline 48) and updates and replaces a recommendation from NICE technology appraisal guidance 80. The recommendations are labelled according to when they were originally published (see About this guideline for details).
Myocardial infarction (MI) is one of the most dramatic presentations of coronary artery disease. It is usually caused by blockage of a coronary artery producing tissue death and consequently the typical features of a heart attack: severe chest pain, changes on the electrocardiogram (ECG), and raised concentrations of proteins released from the dying heart tissue into the blood. MIs are divided into 2 types according to the changes they produce on the ECG:
ST-segment elevation myocardial infarction (STEMI), which is generally caused by complete and persisting blockage of the artery
non-ST-segment elevation myocardial infarction (NSTEMI), reflecting partial or intermittent blockage of the artery.
In England and Wales in 2011/12 more than 79,000 hospital admissions were caused by MI according to the Myocardial Ischaemia National Audit Project (MINAP). Of these, 41% were STEMIs and 59% were NSTEMIs. Twice as many men had MIs as women.
People who have had a STEMI or an NSTEMI benefit from treatment to reduce the risk of further MI or other manifestations of vascular disease. This is known as secondary prevention. Since the late 1990s MINAP has documented the reductions in mortality resulting from changes in acute treatment of MI and the application of secondary prevention measures. Although 30-day mortality was almost 13% for STEMI in 2003/04, it fell to 8% in 2011/12, with similar falls for NSTEMI.
The NICE guideline on the secondary prevention of MI (NICE clinical guideline 48) was published in 2007, offering comprehensive advice to prevent further MI and progression of vascular disease in those who had already had an MI, either recently or in the past (more than 12 months ago). Since 2007, there has been a major change in the management of acute MI, both STEMI and NSTEMI, although more dramatically the former. Primary percutaneous coronary intervention (PCI) has replaced thrombolysis in most cases of STEMI. This improvement in acute treatment may have an impact on the efficacy of secondary prevention, which is one of the reasons this update is needed.
Uptake of cardiac rehabilitation is still low, with only 44% of people starting an outpatient cardiac rehabilitation programme in England, Northern Ireland and Wales after an MI. People also wait an average of 53 days to start an outpatient rehabilitation programme. Interventions that may enhance uptake and adherence to cardiac rehabilitation programmes have been included in this 2013 update.
Drug therapy for secondary prevention is effectively applied nationally, but new findings on antithrombotic therapy, omega-3 fatty acid supplementation, angiotensin-converting enzyme (ACE) inhibitors and beta-blockers have also contributed to a need for this guideline to be updated.