Acute Coronary Syndromes: Reperfusion Strategy. ARC and NZRC Guideline 2011
Article first published online: 14 JUN 2011
© 2011 The Authors. EMA © 2011 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine
Emergency Medicine Australasia
Volume 23, Issue 3, pages 312–316, June 2011
How to Cite
Australian Resuscitation Council, New Zealand Resuscitation Council (2011), Acute Coronary Syndromes: Reperfusion Strategy. ARC and NZRC Guideline 2011. Emergency Medicine Australasia, 23: 312–316. doi: 10.1111/j.1742-6723.2011.01422_20.x
- Issue published online: 14 JUN 2011
- Article first published online: 14 JUN 2011
STEMI occurs in the majority of the patients due to the acute thrombotic occlusion of a major epicardial artery.1–3 This is part of a spectrum of acute syndromes that are the result of disruption or erosion of typically lipid rich atherosclerotic plaque which leads to thrombus formation that occludes the vessel. Myocardial necrosis ensues in a time dependent fashion. Therefore strategies aimed at restoring myocardial perfusion at the earliest possible moment are an important part of the management of these patients. The longer the vessel remains occluded the higher the mortality for this patient group. Restoring coronary blood flow and myocardial reperfusion either by percutaneous coronary intervention (PCI) or fibrinolytic therapy has been demonstrated to improve outcomes in patients presenting within 12 hours of symptom onset.4,5 It has also been shown to be beneficial in other patient groups beyond 12 hours of symptom onset such as those with cardiogenic shock.1,3,6,7
In general the creation of cardiac clinical networks including emergency and medical providers, non capable and capable PCI hospitals is important to facilitate a regional strategy for the delivery of timely revascularisation.3,6–13
Primary PCI (PPCI) is the preferred perfusion strategy with the best outcomes demonstrated in a number of large meta-analyses provided it is performed in a timely manner by an experienced team.14,15 The benefit is mostly driven by reduced rates of recurrent myocardial infarction and reduced rates of intracranial haemorrhage in the PPCI treated patients compared to those receiving fibrinolysis. (Class A;LOE I).
In many parts of Australia, PPCI is not widely available. PPCI is limited by accessibility to a catheterisation laboratory facility, access to appropriately skilled clinician and delays related to the time taken to obtain reperfusion.16
For PPCI to maintain superiorly over fibrinolytic therapy the PCI related delay must be between 45 and 180 minutes depending on the patient's condition e.g. patient age, site of infarction and duration of symptoms.17–19 (Class B;LOE II).
The Cardiac Society of Australia and New Zealand recommends in general, the maximum acceptable delay from presentation to balloon inflation is:20
60 minutes if a patient presents within 1 hour of symptom onset; or
90 minutes if a patient presents later.
(Class B;LOE II).
There are a number of strategies that can be undertaken to reduce the time delay to PPCI.11 These are strategies to improve the systems of care co ordination and they include pre-hospital 12 lead ECGs to facilitate earlier diagnosis and advanced notification of the results of the 12 lead ECG at the receiving institute for rapid reperfusion on arrival of the STEMI patient. Techniques that have evidence to support implementation include21–27 (Class C;LOE III-2).
- • Arranging suitable activation of the catheter laboratory
- • Requiring the catheter laboratory is ready in 20 minutes
- • Having the interventional cardiologist immediately available at the hospital
- • Providing real time data feedback
- • Fostering the support of senior medical management
- • Encouraging a team best approach
In addition to patients with contraindications for fibrinolysis, PCI should be pursued even if there is a delay rather than opting for a no treatment strategy.3,6
For patients with STEMI presenting with shock, primary PCI or coronary artery bypass is clearly a preferred treatment option. Treatment with fibrinolysis should only be considered if there is a substantial delay to PCI.28,29 (Class B;LOE II).
PCI in patients with ROSC:
It is reasonable to perform immediate angiography and if necessary PCI in patients who respond to cardio-pulmonary resuscitation with spontaneous return of circulation after cardiac arrest.30–33 Patients with ST Elevation or new left bundle branch block on the standard 12 lead electrocardiograph should be managed with the recommended medical therapy and revascularisation therapy, including PCI or fibrinolysis, regardless of coma. (Class B;LOE II). Coma is common and should not be a contraindication to angiography and PCI. It is also reasonable to perform immediate angiography and if necessary PCI in selected patients who do not have evidence of ST elevation on their ECG, or prior clinical features such as chest pain, if coronary ischaemia is considered the likely cause on clinical grounds. (Class C;LOE III-1). Therapeutic hypothermia is recommended in combination with PCI and can be commenced as part of the initial treatment preferably prior to PCI.34 Angiography and PCI can be incorporated as part of a standardised post cardiac arrest protocol.35 (Class C;LOE III-3).
Fibrinolytic therapy is more widely available and is beneficial in a wider range of patients who may not have access to PPCI.36–38 Fibrinolytic therapy can be safely given by a trained paramedic, nurse or physician using established protocols.39–43 (Class A;LOE I) The efficacy is greatest given the first three hours of the onset of symptoms. Without timely access to primary PPCI, patients with symptoms of ACS and ECG evidence of ST elevation infarction or true new bundle branch block or true posterior infarction should be treated with fibrinolytic therapy as soon as possible.
In patients presenting early after the onset of chest pain (<1–2 hours) and in certain clinical subsets (<65 years-of-age, anterior STEMI), prehospital fibrinolysis may offer similar outcomes compared to PPCI.18,44,45 (Class B;LOE II).
There are a number of contraindications to fibrinolysis that health care practitioners need to be well aware (see Table 1).1,46 In addition, the older patients are a difficult patient group. They have a high absolute risk of death from their STEMI, have an increased absolute benefit from fibrinolytic therapy but the risk of intracranial bleeding from fibrinolysis is also higher. This is increased in the presence of systolic hypertension of over 180 mmHg. The benefits of fibrinolytic therapy are less impressive in areas of infarction other than an anterior STEMI location.
|Haemorrhagic stroke or stroke of unknown origin at any time|
|Ischaemic stroke in the preceding 6 months|
|Central nervous system damage, neoplasms or structural vascular lesions (e.g. ateriovenous malformation)|
|Recent major trauma/surgery/head injury (within the preceding 3 weeks)|
|Gastro-intestinal bleeding within the last month|
|Known bleeding disorder (excluding menses)|
|Transient ischaemic attack in preceding 6 months, dementia|
|Oral anticoagulant therapy|
|Pregnancy within 1-week post-partum|
|Refractory hypertension (systole. blood pressure >180 mmHg)|
|Advanced liver disease|
|Active peptic ulcer|
In patients with STEMI diagnosed in the pre-hospital setting, reperfusion can be achieved by the administration of fibrinolytics by health care providers in the field. If fibrinolysis is chosen as a reperfusion strategy, it should be initiated as soon as possible and ideally this should occur in the pre-hospital setting. This requires paramedics, nurses or doctors to use well established protocols, have competency based training programs, a quality assurance program and are under medical oversight.41,47,48 (Class B;LOE II).
This strategy may be particularly important in rural areas where there are long transit times to hospital.42,49–51
Triage and inter facility transfer for PPCI:
It is reasonable to consider direct transport to PCI capable facilities for PPCI for patients diagnosed with STEMI by emergency medical services in the prehospital setting, bypassing closer hospitals as necessary, in systems where time intervals between first medical contact and balloon time are brief.4,24,52–54
Transfer of STEMI patients for PPCI from community hospitals is reasonable for those presenting more than 3 h but less than 12 h after the onset of symptoms, provided that the transfer can be achieved rapidly (<2 hrs). The risk of death, reinfarction or stroke is reduced if patients with STEMI are transferred promptly from community hospitals to tertiary care facilities for PPCI.53–55 (ClassA;LOE I).
Facilitated PCI refers to the routine use of fibrinolysis or combined fibrinolysis and glycoprotein IIb IIa inhibitors, routinely prior to PPCI. The strategy of facilitated PCI compared with PPCI is not recommended in STEMI.
A number of studies have examined the strategy of facilitated PCI and they have shown no benefit of PPCI and some studies have shown poor outcomes with routine PCI shortly after fibrinolysis.56,57 (Class B;LOE II).
It is reasonable to perform coronary angiography and PCI in patients who have failed thrombolysis according to clinical signs and insufficient ST segment resolution assessed at 60–90 minutes post lytic therapy.58–63
(Class A;LOE I).
Patients with successful fibrinolysis who are not treated at a PCI capable centre should be encouraged to be transferred for angiography and eventually PCI performed ultimately 6–24 hours after fibrinolysis. This has also been labelled a routine pharmaco-invasive approach.64–68 (Class B;LOE II).
- 12007 Focused Update of the ACC/AHA 2004 Guidelines for the Management of Patients With ST-Elevation Myocardial Infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines: developed in collaboration With the Canadian Cardiovascular Society endorsed by the American Academy of Family Physicians: 2007 Writing Group to Review New Evidence and Update the ACC/AHA 2004 Guidelines for the Management of Patients With ST-Elevation Myocardial Infarction, Writing on Behalf of the 2004 Writing Committee. Circulation 2008; 117: 296–329., , , et al.
- 2Guidelines for the management of acute coronary syndromes 2006. Med J Aust 2006; 184: S9–29.
- 14Primary PTCA versus thrombolytic therapy for acute MI. Cardiology Review 2003; 20: 12–7., , .
- 23Comparison of early mortality of paramedic-diagnosed ST-segment elevation myocardial infarction with immediate transport to a designated primary percutaneous coronary intervention center to that of similar patients transported to the nearest hospital. Am J Cardiol 2006; 98: 1329–33., , , et al.
- 33Post-cardiac arrest syndrome: epidemiology, pathophysiology, treatment, and prognostication: a scientific statement from the International Liaison Committee on Resuscitation; the American Heart Association Emergency Cardiovascular Care Committee; the Council on Cardiovascular Surgery and Anesthesia; the Council on Cardiopulmonary, Perioperative, and Critical Care; the Council on Clinical Cardiology; the Council on Stroke (Part II). Int Emerg Nurs 18: 8–28., , , et al.
- 38Effectiveness of intravenous thrombolytic treatment in acute myocardial infarction. Gruppo Italiano per lo Studio della Streptochinasi nell'Infarto Miocardico (GISSI). Lancet 1986; 1: 397–402.
- 46ACC/AHA guidelines for the management of patients with ST-elevation myocardial infarction–executive summary. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to revise the 1999 guidelines for the management of patients with acute myocardial infarction). J Am Coll Cardiol 2004; 44: 671–719., , , et al.
- 54Multicentre randomized trial comparing transport to primary angioplasty vs immediate thrombolysis vs combined strategy for patients with acute myocardial infarction presenting to a community hospital without a catheterization laboratory. The PRAGUE study. Eur Heart J 2000; 21: 823–31., , , , , .
- 56A randomized trial comparing primary angioplasty with a strategy of short-acting thrombolysis and immediate planned rescue angioplasty in acute myocardial infarction: the PACT trial. PACT investigators. Plasminogen-activator Angioplasty Compatibility Trial. J Am Coll Cardiol 1999; 34: 1954–62., , , et al.
- 61Towards an understanding of the role of rescue angioplasty for failed fibrinolysis: comparison of the MERLIN, RESCUE and REACT trials. J Invasive Cardiol 2007; 19: 359–68., , , , .
- 64Efficacy and safety of immediate angioplasty versus ischemia-guided management after thrombolysis in acute myocardial infarction in areas with very long transfer distances results of the NORDISTEMI (NORwegian study on DIstrict treatment of ST-elevation myocardial infarction). J Am Coll Cardiol 55: 102–10., , , , .
- 68Immediate angioplasty versus standard therapy with rescue angioplasty after thrombolysis in the Combined Abciximab REteplase Stent Study in Acute Myocardial Infarction (CARESS-in-AMI): an open, prospective, randomised, multicentre trial. Lancet 2008; 371: 559–68., , , et al.