Download Management of ST Elevation Myocardial Infarction with Hospital

Management of ST Elevation Myocardial
Infarction with Hospital Transfer Guidelines Dunedin and Community Hospitals (District)
Guidelines for the management of ST elevation.
Note: This document is for staff at Dunedin Hospital and those at Southern DHB
community hospitals from where STEMI patients are transferred to Dunedin. It does not
apply to Southland Hospital.
Associated Policy
None.
Background
ST elevation myocardial infarction (STEMI) is the highest risk
acute coronary syndrome for short-term (30 days) adverse
outcomes.
Outcomes in terms of mortality, heart failure, arrhythmia,
length of hospital stay, left ventricular ejection fraction, longterm quality of life, symptoms, etc. are highly influenced by
treatment, particularly delays to successful reperfusion.
A 60-minute hospital delay (from 90 minutes to 150 minutes)
will more than double in-hospital mortality from 3.0% to 7.4%
(equating to 1-2 extra deaths from STEMI annually in Dunedin
Hospital).
Each 15-minute decrease in reperfusion time will result in 6.3
fewer deaths per 1000 patients treated. Other adverse
outcomes/complications (as listed above) will also be
unfavourably affected by delay.
Acute reperfusion, when indicated, may either be mechanical
or pharmacological, and is optimally determined by a
cardiologist tailoring it to the patient’s individual clinical
circumstances.
It is Cardiology Unit policy to provide primary percutaneous
coronary intervention (PCI) for all suitable patients
presenting to Dunedin Hospital. Those patients presenting to
other hospitals (where primary PCI cannot be performed at
Dunedin Hospital within 120 minutes), are treated with
thrombolysis and early transfer to Dunedin Hospital.
Strategy
Triage
1. Immediate triage of patients with symptoms suggestive of
myocardial infarction to have a 12-lead electrocardiogram
(ECG) with correct interpretation within 10 minutes of
triage time. The appropriate staff member sighting /
interpreting will document their initials, date, and time of doing
so.
2. Possible fast-tracking of patients with early notification of the
Emergency Department (ED) and Cardiology Unit by the
Ambulance Service or peripheral hospital / GP, if they have
obtained a diagnostic ECG.
Early discussion between ambulance staff or the peripheral
service with the on-call cardiologist - whether direct transfer to
the Catheter Laboratory or Coronary Care Unit (CCU) - is
appropriate.
Medical registrars out of working hours should direct outside
calls relating to STEMI or shock directly to the on-call
cardiologist and, as a backup, obtain phone contact
(preferably mobile) details.
3. During working hours (8.00am to 5.00pm, Monday to Friday),
immediate notification of the CCU registrar.
Other periods: immediate page or phone contact with on-call
cardiologist by the ED physician, or appropriate delegate, to
discuss reperfusion strategy.
A focused medical history and physical examination needs to
be discussed to determine appropriate reperfusion strategy
and adjunctive treatments - see the STEMI Protocol Flowchart
(District) (73644).
4. A single call from the ED to a cardiologist (or CCU registrar
between 8.00am and 5.00pm normal weekdays) may then be
followed by a single call by the cardiologist to activate the Cath
Lab, if catheter-based reperfusion is opted for.
It is policy that primary PCI should be routinely offered to
patients judged suitable for treatment with this method of
revascularisation. Patients not meeting this criterion will be
assessed for treatment with thrombolysis.
5. The progress of every STEMI will be tracked routinely and
prospectively with regular rapid-cycle audit and performance
feedback to all team members and stakeholders.
Refer to the STEMI Protocol Flowchart (District) (73644).
Reperfusion Overview
Indications
Clinical history consistent with acute myocardial infarction (MI)
within the last 12 hours (chest pain for more than 20 minutes
that started less than 12 hours previously); and
ECG changes:
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≥1mm ST elevation in two contiguous limb leads; or
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Males ≥ 2mm and females ≥1.5mm ST elevation in
two contiguous chest leads V1 to V3; or
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≥1mm in two contiguous chest leads V4 to V6; or

Left bundle branch block (LBBB) not known to be old
Consideration should be given for reperfusion therapy in
patients with left bundle branch block that is not known to be
old, and who have a convincing clinical history for acute MI.
The ST-elevation myocardial infarction: New Zealand
management guidelines 2013, outline the additional ECG
evidence for acute MI in the presence of LBBB. These patients
should be discussed with the on-call cardiologist before
proceeding.
Patients with an inferior MI should have an ECG with a V4R
lead.
Contraindications to
Thrombolysis
Prior to proceeding with fibrinolysis the following should be
checked for in all cases:
Absolute contraindications
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Previous haemorrhagic stroke (or stroke with
haemorrhage not excluded by scanning)
Known intracranial or spinal tumour or arteriovenous
malformation
Ischaemic stroke within six months
Neurosurgery within six months
Recent lumbar puncture
Suspected aortic dissection
Active bleeding or bleeding diathesis (excluding
menses)
Significant closed head or facial trauma within three
months
Uncontrolled hypertension (SBP >180mmHg or DPB
>110mHg). (Repeat after GTN/morphine and
reconsider fibrinolysis)
Internal bleeding within six weeks of major surgery,
trauma or bleeding within six weeks
Relative contraindications
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Traumatic pulmonary resuscitation <three weeks
Non-compressible vascular puncture
Pregnancy
Active peptic ulcer
Advanced liver disease
Diabetic retinopathy
Current use of anticoagulants with INR >2 : the
higher the INR the greater the risk of bleeding
Note: The risk of giving thrombolysis needs to be weighed against
the benefits. For example, it is possible a patient with a large
anterior STEMI with cardiogenic shock, who presents early, may
benefit from fibrinolysis despite apparent (even absolute)
contraindications. The on-call cardiologists should be consulted to
discuss the risks and benefits before deciding not to give
fibrinolytics to a patient on the basis of contraindications.
The following are not contraindications to fibrinolysis:
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Hypotension
Menstruation
Age
Primary PCI and Rescue PCI
There is increasing evidence for the role of primary
percutaneous coronary intervention (Primary PCI) as first line
therapy when it can be offered rapidly by an experienced
team. PCI should also be considered when fibrinolysis is
contraindicated or has not achieved reperfusion.
Primary PCI
Primary PCI should be considered immediately (including
transfer from outside centres) in the presence of cardiogenic
shock (or a high likelihood of cardiogenic shock on the basis of
involvement of massive territory).
In peripheral centres, the on-call cardiologist should be
consulted and retrieval initiated at the same time as fibrinolysis
is being given.
Immediate transfer from a remote site should be considered
whenever fibrinolysis is contraindicated and a high-risk
situation exists.
Be aware that fibrinolytics work less well on an older more
organised clot (> about 4hrs) and the advantage of primary
PCI vs. fibrinolytics is greater in this group of patients.
It may be appropriate to immediately transfer some patients
who present late, for primary PCI, although this decision
should be made on a case-by-case basis.
Rescue PCI
Rescue PCI should be considered in patients who fail to
reperfuse, particularly if a large territory is involved (this would
apply to patients in remote centres also).
Indicators that a large territory is involved:

Extensive anterior MIs or inferior MIs with posterior
extension as indicated by marked ST depression in
the septal leads or left bundle branch block or right
bundle branch block.
Indicators of failed reperfusion include:
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Ongoing chest pain and failure to see a reduction of
at least 50% in the amount of ST elevation, in the
lead with the most initial ST elevation, at 90 minutes
after administration of the fibrinolytic.
Transfer of Patients from Other Facilities to Dunedin Hospital
The ability of rural hospitals to safely manage patients with
myocardial infarction varies - both between hospitals and at
different times in the same hospital. This depends on the
physical resources available (including laboratory and
radiology services) as well as the skill and experience of the
clinical staff on duty.
Transfer should be discussed with the cardiologist on call at
the time of administering thrombolysis.
Later transfer for angiography and intervention (PCI or CABG)
is indicated for most STEMI patients, particularly those with
recurrent pain / ischaemia post-infarction.
Fibrinolytic Agent
Tenecteplase is the preferred fibrinolytic agent.
Procedure
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Insert two IV lines (avoid using the right wrist, which
is the preferred arterial access site for PCI) — one
for drugs and the other for drawing blood.
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Draw blood for troponin, full blood screen, glucose,
U&Es, LFTs, prior to therapy.
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Bloods for lipids should also be taken, preferably
fasting, but definitely within 12 hours of the onset of
pain.
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Tenecteplase is administered as a single intravenous
bolus over 5-10 seconds.
Tenecteplase is incompatible with dextrose-containing
solutions. IV lines should be flushed before and after
administration of tenecteplase with normal saline.
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Dosage is based on weight of patient
For example:
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30mg
35mg
40mg
45mg
50mg
for
for
for
for
for
patients weighing <60 kg
those weighing 60 to 69 kg
those weighing 70 to 79 kg
those weighing 80 to 89 kg
those weighing ≥90 kg
If weight is not readily available, it should be estimated.
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The syringe is pre-marked according to patient
weight.
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After mixing, the appropriate volume of
reconstituted tenecteplase solution should be drawn
back into the syringe from the vial.
Complications of Fibrinolysis
Bleeding
This can be minimised by the avoidance of unnecessary
punctures and careful history taking (see 'Contraindications'
above).
Unsuccessful IV access sites or blood gas sites should have
compression bandages applied.
Treatment with fresh frozen plasma and protamine should be
considered if serious haemorrhage occurs.
Any deterioration in the level of consciousness needs to be
treated as a cerebral bleed until proven otherwise by CT
[computed tomography].
Arrhythmias
Reperfusion arrhythmias are common and include:
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Bradycardia / complete heart block - occurs
most commonly with reperfusion of inferior MI.
Usually it resolves within minutes. If necessary treat
with atropine and fluids.
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Idioventricular rhythm - no treatment is
necessary if the heart rate is <120 and the patient is
not hypotensive. Keep potassium between 45mmol/L.
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Non-sustained VT - runs are common and usually
subside with time. Observe for 10 minutes before
contemplating antiarrhythmics. Keep potassium
between 4-5 mmol/L.
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Sustained VT / VF - defibrillation and intravenous
amiodarone 300mg bolus. (Routine use of IV Mg is
not recommended as no benefit in randomised trials
of VF; there may be a role in torsades de pointes
with prolonged QT interval.)
Adjuvant Medications
Medication
Directions
Aspirin
300mg chewed: should be given immediately, if not already given.
Continue 100-150mg per day.
Consideration should be given to giving additional doses of aspirin
to patients on NSAIDs [non-steroidal anti-inflammatory drug] until
the effect of the NSAID wears off.
P2Y12 Inhibitors
Ticagrelor
Primary PCI pathway. Ticagrelor is the preferred agent:180mg
stat, then 90mg twice daily. This dosing is also used in patients
already treated with clopidogrel.
Thrombolysis pathway. Ticagrelor has not been studied as an
adjunct to fibrinolysis and should not be used in the first 24 hours.
Ticagrelor can be started >24 hours after fibrinolysis with a loading
dose of 180mg and continued 90mg twice daily for one year.
Clopidogrel
Thrombolysis pathway. 300mg stat for patients ≤75yrs, 75mg stat
for patients >75 yrs, followed by 75mg daily. Can be changed to
ticagrelor > 24 hours after fibrinolysis.
Primary PCI pathway. 600mg stat followed by 75mg daily. Used in
selected patient cohorts: those on dialysis, those with severe lung
disease, advanced conduction disease, those at very high bleeding
risk.
Morphine
As needed for pain control.
Oxygen
Supplemental oxygen is indicated for patients who are hypoxic
(saturation < 93%) and those with cardiogenic shock to correct
tissue hypoxia.
O2 is a coronary vasoconstrictor and as such may have detrimental
effects. It should be administered with caution to patients with
COPD [chronic obstructive pulmonary disease] and CO2 retention.
Heparin
Enoxaparin is the heparin of choice with tenecteplase.
Enoxaparin
Patient is <75 years of age:
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Enoxaparin 30mg intravenous bolus to be given before
the administration of tenecteplase.
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15 minutes later - enoxaparin 1mg/kg (up to a maximum
dose of 100mg) subcut and continue this 12-hourly up to
eight days or until the patient is discharged.
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30mg enoxaparin should be injected as 0.4mL into a
tuberculin syringe. Waste 0.1mL and inject the remainder
that is 30mg (0.3mL) into the line and flush.
Patient is ≥75 years of age:
Note: Older patients who received full doses of enoxaparin during
fibrinolysis trials had an excess amount of bleeding.
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Do not give the IV dose of enoxaparin.
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15 minutes after tenecteplase, administer sub-cut
enoxaparin 0.75mg per kg (up to a maximum dose of
75mg) and continue this at 12-hourly intervals up to eight
days or until the patient is discharged.
Renal impairment:
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Unfractionated
Heparin
Enoxaparin dosing should be reduced in renal impairment.
Patients with an eGFR of <30mL per minute should have
the dosing interval extended to q24 hours.
Occasionally, it may be preferable to administer a heparin infusion
rather than enoxaparin. This is likely to be for patients who have
very severely impaired renal function or for whom there is a high
likelihood of bleeding (and it is preferable to use an agent which will
both wear off quickly and can be reversed).
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Initially administer an IV bolus of heparin - 60 units per
kg up to a maximum of 4000 units.
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Commence the heparin infusion at 12 units per kg per hr
up to a maximum of 1000 units per hour. Perform the first
APTT at six hours and reduce the dose if the APTT is
>150.
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After 12 hours, aim for an APTT in the range of 50-70
seconds.
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Adjust the rate according to the ward protocol.
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Continue the heparin infusion for up to 48 hours.
Beware of the risk of reactivation of thrombosis in the first 10 hours
after heparin withdrawal.
Beta Blockers
It may be harmful to administer IV beta-blockers to STEMI patients
who have contraindications to beta blockade, signs of heart failure
(HF) or low-output state, or other risk factors for cardiogenic shock.
Beta blockers still have a role in secondary prevention. CHF/poor
LV function is an indication for the use of beta-blockers, but only
with careful titration.
Oral beta-blocker therapy should be initiated in the first 24 hours for
patients who do not have any of the following:
1. Signs of heart failure.
2. Evidence of a low output state.*
3. Increased risk of cardiogenic shock; or
4. Other contraindication to beta-blockade (PR interval
greater than 0.24 seconds, second or third degree heart
block, active asthma or reactive airways disease.
IV Metoprolol
IV metoprolol can be considered for STEMI patients who are also
hypertensive or have a tachyarrhythmia or have ongoing chest pain.
IV metoprolol 15mg (total) — administer as three doses, each 5mg,
with two minutes between doses. Monitor rhythm, rate and BP.
Patients who have initial contraindications in the first 24 hours after
STEMI should be re-evaluated for beta-blockade for secondary
prevention later in the admission.
Oral Metoprolol
The usual starting dose is short acting metoprolol 25mg tds, though
12.5mg tds may be more appropriate if there are concerns about
tolerance.
Aim for metoprolol CR 95mg daily by discharge, but titrate slowly if
there are concerns about haemodynamic stability or poor LV
function.
Continue indefinitely.
* Risk factors for cardiogenic shock (the greater the number of risk
factors present, the higher the risk of developing cardiogenic shock) are
age greater than 70 years, systolic blood pressure less than 120mmHg,
sinus tachycardia greater than 110 bpm or heart rate less than 60 bpm,
and increased time since onset of symptoms of STEMI.
GTN Infusion
This may be considered for 24-48 hours, particularly if there is any
ongoing chest pain or left ventricular failure.
Renin /
Angiotensin /
Aldosterone
Inhibitors
ACE-inhibitors should be considered for all patients.
Cilazapril
Initially 0.5mg - 1.25mg daily depending on blood pressure / age /
renal function. Aim for 5mg daily.
Patients with evidence of CHF, anterior infarction, EF < 40% should
start ACE-inhibitors within 24hrs after admission if SBP > 100
mmHg. Other patients can be started the following morning.
Continue for six weeks or indefinitely if the MI is large and anterior,
or there is evidence of impaired LV function.
Because of its shorter half life, consider using low-dose captopril
rather than cilazapril as the initial ACE-inhibitor, when hypotension
or increased sensitivity to ACE-inhibitors, is likely (e.g. frail, elderly).
Angiotensin receptor blockers (ARB) should be given to patients
with STEMI with indications for but who are intolerant of ACE
inhibitors.
Spironolactone should be given to those without contraindications
who are already treated with a beta blocker and ACE inhibitor with
an EF < 40%.
Insulin Infusion
All patients with a BSL > 11mmol/L (regardless of whether or not
they are a known diabetic) should be considered for an insulin
infusion to maintain their BSL in the range of 7.7-10mmol/L.
Monitor K closely.
Statins
Commence Atorvastatin 80mg daily within 24 hours.
Aim to reduce LDL to < 2.0mmol/L but continue on at least 40mg
Atorvastatin regardless of lipid levels.
Potassium
Supplements
Serum K should be maintained at ≥4.0 mmol/L with K supplements.
Fluids
Patients with RV infarction (as evidenced by inferior MI, low BP,
high JVP and no LV failure and supported by ST elevation on V4R
lead) may need additional fluids. Aim for oral intake of 2000mL
daily. Additional fluid boluses (250mL N/Saline) may be needed to
maintain the BP.
Hypertension
NSAIDs should be stopped. If it is essential to use an NSAID longer
term, then a non-selective agent (e.g. naproxen) should be used.
HRT [hormone replacement therapy] should be discontinued.
Associated Documents:

STEMI Protocol Flowchart - Dunedin and Community Hospitals (District) (73644)

Preparation and Administration of Tenecteplase to Acute Myocardial Infarction
Patients (District) (57503)
References:

ST-Elevation Acute Coronary Syndrome Guidelines Group and the New Zealand
Branch of the Cardiac Society of Australia and New Zealand. 2013. ST-elevation
myocardial infarction: New Zealand management guidelines; New Zealand Medical
Journal (NZMJ) 126-1387; NZMA http://www.nzma.org.nz/journal/read-thejournal/all-issues/2010-2019/2013/vol-126-no-1387/5953

O'Gara, Patrick T., et al. 2013. ACCF/AHA Guideline for the Management of STElevation Myocardial Infarction, Journal of the American College of Cardiology
(JACC); 61:e78-140; doi:10.1016/j.jacc.2012.11.019

Steg, Ph Gabriel, et al. 2012. ESC Guidelines for the management of acute
myocardial infarction in patients presenting with ST-segment elevation. European
Heart Journal; 33; 2569-2619. doi;10.1093/eurheartj/ehs215.
General Notes
Scope of Practice: Ensure you are fully qualified to perform the role specified in any document.
Deviations: If you need to deviate from any procedure, policy, or guideline, make notes and follow
up.
Caution - Printed Copies: Printed copies of this document cannot be relied on after the date at the
bottom of the page. Check issue date and version number against the electronic version on MIDAS to
ensure that they are current.
Disclaimer: This document meets the Southern District Health Board's specific requirements. The
Southern DHB makes no representations as to its suitability for use by others, and accepts no
responsibility for the consequences of such use.
Document Data for 57502 V4
Applies to: Medical staff - Otago and community hospitals (Global: Yes)
What has Changed: AMENDED: Several changes throughout - specifically chapter titled fibrinolysis changed to reperfusion
and removed some text in PCI section.
Service Actions: Replace any older printed copies with this version.
MIDAS ID: 57502 Version 4 (Old ID: n/a), Document Type: Guidelines
Issued: 22/10/2014, Released: 22/10/2014, Due for Review: 1/10/2016, Authorised by: Chief Medical Officer
Document Owner: Medical Directorate (2510 - Ward 7C Cardiology/Nephrology )
Author: Michael Williams, Contact Name: Janette Gilder, Contact Phone: 8960 (Otago)
Keywords: ST elevation, acute myocardial infarction, STEMI thrombolysis, fibrinolysis, tenecteplase, enoxaparin,
reperfusion
Reviewed By: Michael Williams