|Ischaemic heart disease
|Assessing Chest Pain
|ACS - General
|ACS - STEMI
|ACS - NSTEMI
|ACS - GRACE Score
|ACS - ECG Changes
|ACS -Cardiac Troponins
|ACS - Post MI arrhythmias
|ACS: Right Ventricular STEMI
Adhere to local guidelines and expert senior cardiology advice. Always closely monitor and be ready to defibrillate. A STEMI is usually due to a complete obstruction of a coronary artery. It is important to recognise as reperfusion therapy can save lives and reduce morbidity.
|Initial Management summary for Acute STEMI|
- Oxygen to keep sats 94-98%, telemetry, defibrillator to hand
- Get 12 lead ECG, IV access, FBC, U&E, Glucose, Lipids, Troponin, Dimer
- GTN spray. Morphine 5 mg by slow IV
- Antiemetic : Metoclopramide 10 mg IV
- Aspirin 300 mg stat (US ASA 162–325 mg PO/PR) + second agent
- Consider Clopidgrel 300 mg or Prasugrel 60 mg or Ticagrelor 180 mg
- Metoprolol 5-15 mg IV or 50-100 mg stat PO
- Onset < 12 hrs then consider PCI or Thrombolysis
Management of STEMI (Chest pain + ECG)
Refer the patient immediately to Cardiology for Primary Percutaneous Intervention (Primary PCI); the target door-balloon time is within 60 mins. Establish an IV line. Take blood samples for full blood count, U&Es, glucose, troponin, and lipids. A chest x-ray should be requested but should not delay therapy.
- Occluded coronary artery
- Harm depends on which artery and how proximal the lesion
- This determines how much myocardium is damaged
- Prompt treatment is very important
- Central or retrosternal chest pain/tightness/heaviness
- Radiates to neck/shoulder/jaw
- Associated dyspnoea, nausea, vomiting
- Occasionally silent - fall, syncope with ECG changes
- Pulmonary oedema, heart block
ECG Criteria (STE = ST elevation)
- STE in two contiguous leads (1 mm = 0.1 mV)
- > 2 mm of STE in 2 contiguous V1-V6 leads in men (1.5 mm for women)
- > 1 mm in 2 other contiguous leads
- New LBBB block (Use Sgarbossa Criteria)
- RV Infarction STE in V3/V4 on Right side of chest
- Posterior MI: deep ST depression and tall R waves in leads V1 to V3.
- will be elevated at 0 and 3 hours. However no need to wait for troponin levels if chest pain and ECG changes as above.
- If there is uncertainty and troponin not available a rapid bedside Echocardiogram may support diagnosis showing regional wall reduced motility that corresponds with ECG findings.
- NB: MI can be silent in elderly or diabetics. Ensure defibrillator available
- Clinical Assessment/NEWS/ Telemetry. IV access.
- Send FBC, U&E, LFT, Troponin and Dimer if PE/Dissection suspected
- Admit to CCU telemetry bed and at least daily Review looking for complications
Early Management and Medications
- Give Oxygen to achieve SaO2 94-98%
- GTN 400 mcg per spray or S/L GTN tablet (300 or 500 mcg) if Chest pain, SBP > 110 mmHg, LVF
- Pain relief: Morphine 2.5-5 mg slow IV which may be repeated as needed or Diamorphine 2.5 mg slow IV which may need repeating
- Antiemetic: Metoclopramide 10 mg IV Oxygen and Monitor
- Antiplatelet: Aspirin 300 mg PO stat
- Commence a P2Y12 antagonist: one of the following (discuss with cardiology if risk of bleeding)
- Clopidogrel 300-600 mg PO Stat
- Ticagrelor 180 mg PO stat
- Prasugrel 60 mg PO stat
- Metoprolol 5-15 mg IV or 50 mg PO BD if LV dysfunction, Tachycardia (not if Asthma or Pulmonary oedema). Alternatives are Diltiazem for those who cannot take a beta-blocker.
- Furosemide 40-80 mg IV if pulmonary oedema
- Ramipril 1.25 mg OD
- Fondaparinux 2.5 mg OD SC may be given if no reperfusion therapy
- Check blood glucose on admission, and check fasting blood glucose at day 4 or HBA1C predischarge for anyone with hyperglycaemia at presentation (blood glucose >11mMol/L).
- Glucose control is important (aim BM 6-11 mmol/L), but take care to avoid hypoglycaemia (BM <4.4) which can worsen outcomes in diabetic patients with acute coronary syndromes.
- If control poor in the CCU e.g. BM > 11 mmol/L then consider starting VRII.
Reperfusion therapy if chest pain onset < 12 hrs
Primary PCI should be done within 60-90 min of admission
- Urgent transfer to Catheterisation lab if available within 90 mins of call. . Access via radial artery if it can be done within 120 minutes often with GPIIb/IIIa receptor antagonist IV then move to CCU. Anticoagulation during PCI (specialist advice) may be LMWH or UFH during PCI.
- Femoral route via the femoral artery to iliacs to abdominal aorta and
then thoracic and arch and even into the left ventricle
- Radial artery is becoming a more popular route. Catheter passes along
Brachial, subclavian and aortic arch down to the coronaries
- The catheter is then threaded into the Ostia of in turn right
and left coronary arteries and radiocontrast dye given under x-ray
imaging. Identifies and records coronary anatomy and any lesions. Dye can also be injected into the LV which will show LV function and aortic valve regurgitation
- The information provided can help the clinician decide the need for
medical therapy alone or plus either PCI or CABG or Valve replacement if
that is the pathology
- PCI centres should have individuals skilled in the procedure (>75 cases/year) In a high-volume centre (>200 cases/year)
- This can be done at the same time or planned for later
- A a fine wire can be passed into the artery and past the
occlusive lesion via the coronary artery catheter and over this an
angioplasty balloon can be threaded which could be inflated by an
obstructive lesion. The problem was local damage, arterial dissection
and subsequent restenosis and in some cases acute closure of the vessel
(which could mean urgent bypass required). These made this a risky
business. This was reduced by the use of stents
- Stents are mesh like tubes which splint the vessel open and
reduce these complications. Stents are now indicated in almost all
coronary interventions where there is identifiable disease causing
symptoms. Newer bare metal and drug eluting stents contain agents that
reduce acute stent thrombosis and vascular smooth muscle growth. They
require prolonged courses of antiplatelets.
- Additional agents (follow local guidance)
- With primary PCI : Aspirin Oral dose of 150-325 mg. Clopidogrel Oral
loading dose of at least 300 mg, preferably 600 mg.
inhibitors Abciximab: i.v. bolus of 0.25 mg/kg bolus followed by 0.125
mg/kg per min infusion (maximum 10 mg/min for 12 h)
- With fibrinolytic treatment: Aspirin Oral dose of 150-325 mg.
Clopidogrel Loading dose of 300 mg if age <75 years; 75 mg if
- Without reperfusion therapy. Aspirin Oral dose of 150-325 mg and
Clopidogrel Oral dose of 75 mg
Thrombolysis: first check indications and contraindications. Consider if PCI cannot be provided within 120 minutes of ECG.
- Streptokinase (Streptase) is indicated up to 12 hours after onset of symptoms. 1.5 million units over 30-60 min i.v. Cannot be used if given before due to the formation of neutralising antibodies. It is administered as an IV infusion over 1 hour. Associated with hypotension, infrequent allergic reactions and, rarely, anaphylaxis.
- Alteplase (recombinant human tissue plasminogen activator, rtPA) can be delivered in a standard or accelerated regimen. The accelerated regimen, which is much more commonly used, is indicated up to 6 hours after symptom onset and is delivered by an initial IV bolus injection, followed by two IV infusions, the first given over 30 minutes and the second over 60 minutes. The standard regimen is indicated between 6 and 12 hours after symptom onset and requires a bolus injection followed by five infusions over 3 hours.
- Tenecteplase is indicated up to 6 hours after symptom onset. Tenecteplase (TNK-tPA) Single i.v. bolus. 30 mg if < 60 kg, 35
mg if 60-70 kg, 40 mg if 70-80 kg, 45 mg if 80-90 kg and 50 mg if >
- Absolute contraindications
- Haemorrhagic stroke or stroke of unknown origin at any time,
Ischaemic stroke in preceding 6 months
- CNS trauma or neoplasms, Recent major trauma/surgery/head injury
(within preceding 3 weeks)
- GI bleeding within the last month, Known bleeding disorder,
Aortic dissection, Non-compressible punctures (e.g. liver biopsy,
- Relative contraindications
- TIA in preceding 6 months, Oral anticoagulant therapy
- Pregnancy or within 1 week post-partum
- Refractory hypertension (systolic blood pressure >180 mmHg
and/or diastolic blood pressure >110 mmHg)
- Advanced liver disease, Infective endocarditis
- Active peptic ulcer, Refractory resuscitation
Complications of ST-Elevation MI
- Ventricular tachycardia often seen acutely during
ischaemia/infarction. Treat with IV lidocaine, IV amiodarone if
persistent VT. Ensure normal potassium and magnesium. DC shock if
compromised to return to sinus rhythm
- Ventricular fibrillation: seen early on. Needs Defibrillation. manage of telemetry on ITU. Antiarrhythmics not usually needed. VF after the first 24 hrs is more concerning and may need ICD long term. Commence beta-blockade. late arrhythmias or persisting seek expert help.
- Cardiac rupture into the pericardium with tamponade and death
usually, after the first few days as the necrotic wall softens.
Clinically causes EMD.
- Pulmonary embolism due to DVT. Should be reduced by the use of LMWH.
- Reinfarction if there is plaque rethrombosis with vessel occlusion.
Consider urgent thrombolysis or repeat PCI. Discuss with local centre.
- Pulmonary oedema. Treat with IV diuretics egFurosemide 50-100 mg
IV. Suggests LV impairment and poor prognostic marker.
- Cardiogenic shock - again suggests poor prognosis and suggests severe loss of LV myocardial muscle mass.
- RV Infarction: Volume loading treats the apparent hypotension,
raised JVP and clear lung fields with an inferior STEMI. Echo is useful and evidence of a Right coronary artery infarction on ECG. Tall R wave in V1. ST elevation in V4R.
- Ventricular septal rupture can occur and present as heart failure with a loud PSM. Treat as a failure. Echo to confirm. May require IABP.
Surgery within 48 hours.
- Papillary muscle rupture can occur acutely with breathlessness and a
loud pansystolic murmur. There may be acute severe MR with marked pulmonary oedema. Echo to confirm. Usually seen with a small infarct of the posteromedial papillary muscle in RCA or Cx distribution. Benefit from IABP as a bridge to surgery. Cardiac surgical assessment for MVR
within 48 hours.
- Atrial fibrillation is not uncommon and is treated with digoxin
(ensure potassium over 4 mmol/l) or amiodarone for rate control. Rhythm control can be attempted through drugs such as amiodarone or DC
cardioversion may be contemplated. Warfarin should be considered.
- Sinus bradycardia seen with inferior MI. Withhold beta-blockade and
Give atropine and consider Isoprenaline if persists. Temporary basis if
- Second/Third-degree AV Block: Consider Atropine and External pacing.
A temporary pacing wire may be needed. Avoid subclavian route if on anticoagulants.
- First-degree heart block: Needs no treatment. If associated with new-onset LBBB it may suggest widespread anterior wall infarction and pacing
may be needed.
- Early Pericarditis: different pain to the MI. Can be seen on day 2 or 3 and maybe positional and affected by respiration. May need opiates. Avoid NSAIDs.
- Dressler's syndrome occurs weeks after and is an autoimmune response following a transmural infarct. Fever, pericardial pain. Treat with NSAIDS/Steroids.
- Ventricular remodelling: harmful reaction to large transmural STEMI with thinning of the ventricular wall. Prevent with ACEI.
- There is still a role for Coronary artery bypass grafting. It may be
a primary procedure for some or carried out after failed PCI and
stenting or where the lesions are too high risk for PCI.
- The indications are those with
- LMS stenosis > 70%
- Proximal LAD stenois > 70%
- Triple vessel disease stenois > 70%
- Those with diabetes or Poor LV function are at higher risk but have
most to gain. The operation is usually done on cardiopulmonary bypass
through a median sternotomy.
- The plan is to bypass the existing stenotic lesions using either
- Left internal mammary grafted into the LAD beyond the stenosis.
Arterial grafts have better long term patency.
- Reversed (they have valves) saphenous vein grafts from the legs to
bypass coronary obstructive lesions.
- CABG patient is left with sternal wound and visible scars where
veins stripped on lower legs if a reversed saphenous vein graft
(SVG) was used.
Implantable Cardioverter Defibrillator
- VT/VF 24 hrs of more after admission
- EF < 35% 6-12 weeks after ACS