STEMI Flashcards
What are the symptoms of ACS?
(6)
- Crushing chest pain radiating to left arm/jaw
- Sweating (marked) : 2nd to high sympathetic drive
- Nausea + Vomiting
- Breathlessness
- Palpitations
- BP, pulse and oxygen saturations may be normal
What are the atypical symptoms of ACS?
(4)
- Epigastric pain
- Indigestion-like symptoms
- Insolated dyspnoea
- Syncope
What is the common atypical presentation in women?
Middle / upper back pain
What is the pathophysiology of a STEMI?
- complete occlusion of a coronary artery secondary to a thrombus
- Leading to ischaemic and necrosis of myocytes
- Degree of myocardium damage is dependant on the areas supplied by the coronary artery and efficiency of reperfusion
Which investigation is diagnosic?
ECG is diagnostic
How long should CP last for in a STEMI?
CP should last for > 20 minutes
What is the criteria for ST elevation on ECG for a STEMI?
(4)
ST elevation in two contiguous leads of v2-v3
* >2.5 mm in Men <40
* >2mm in Men >40
* 1.5mm in Women
* 1 mm ST elevation in other leads
What else may indicate a STEMI other than ST elevation on ECG?
New LBBB
What ECG changes may be seen in a posterior STEMI?
Deep ST segment depression in leads** V1 - V3**
What is the criteria for ‘Pathological’ Q waves?
- Any Q wave in leads v2-v3
- Deep >1mm in other continuous leads
What do Q waves indicate?
may indicate previous ‘silent’ MI
Where are Q waves normally seen on an ECG?
normally deep in >2mm in III or avR
What is the criteria for a PCI to be administered?
(3)
- if presented within 12 hours of onset of symptoms
** and** - PCI can be delivered within 120 minutes of presentation to hospital
OR
- if signs of on going ischaemia / symptoms or shock or HF / malignant arrhythmias
What is the process of a PCI?
(3)
- Catheter inserted into blood vessels to area of occlusion
- a balloon is inflated and stent is placed.
- Right radial access is preferred over femoral access
STEMI : PCI - Management
- STEMI
- Asprin 300mg
- 2nd antiplatelet :
* Praugrel
* Clopidogrel if high risk of bleeding/concurrent anticoagulant therapy - PCI -
i) Radial access
* Unfractionated heparin (Dalteparin/Enoxaparin)
* Bailout Glycoprotein IIB/IIIA inhibitor (tirofiban and eptifibatide) - if worsening or persistent thrombus
ii) Femoral access
* bivalirudin (thrombin inhibitor) with bailout GPI
NSTEMI/Unstable angine : Management
- NSTEMI/Unstable angina
- Asprin 300mg
- Fondaparinux if no immediate PCI planned
* If immediate PCI planned or creatinine >265 then : Unfractionated heparin - GRACE SCORE
* High - PCI
* Low - Ticagrelor (2nd antiplatelet)
STEMI : Fibrinolysis management
- STEMI
- Asprin 300mg
- Fibrinolysis
* Antithrombin - Second antiplatelet
* Ticagrelor - given following procedure
When should dual antiplatelet therapy be administered?
To all patients who are due to undergo PCI
* if the patient is not taking an oral anticoagulant: prasugrel
* if taking an oral anticoagulant: clopidogrel
What are the specific indications for giving clopidogrel?
- High bleeding risk
- Patient is already taking an anticoagulant
What is a common drug which interacts with clopidogrel?
Omeprazole +Clopidogrel
* Omeprazole interacts with clopidogrel and reduces it effectiveness
* Omeprazole is a P450 inhibitor but not lansoprazole
What is thrombolysis
Include examples of thrombolytic drugs
- Use of thrombolytic drugs to break down blood clots by activating an called plasminogen to form plasmin which degrades blood clots (fibrin)
- e.g. Alteplase, Streptokinase
What is the criteria behind starting anticoagualation in a patient due to undergo treatment for a STEMI?
*If PCI - hold anticoagulant
* If fibrinolysis - start anticoagulant at the same time
e.g. Fondaparinux
What are the main CI for thrombolysis?
(7)
- Active bleeding, recent haemorrage/surgery/trauma
- Stroke <3 months
- Bleeding disorder
- Aortic dissection
- Intra cranial neoplasm/ Recent head injury
- Severe hypertension
- Concurrent anticoagulation use
What should you do if thrombolysis is CI?
- Chose primary PCI instead regardless of anticipated time to access this intervention
Which is more effective - Thrombolysis or PCI?
Thrombolysis has a higher risk of bleeding and less efficacy.
When should PCI be offered after thrombolysis?
offer angiography if
* ECG 60-90mins post shows residual ST elevation
* Recurrent myocardia ischaemia/chhest pain post fibrinolysis
What is a type 1 MI and explain its pathophysiology?
- Non occlusive thrombus that develops in a disrupted atherosclerotic plaque
- Unstable plaques have soft lipid rich contents covered by a fibrous cap
- If plaque is disturbed - exposure of the lipid rich core triggers the coagulation cascade
- Leading to super-imposed thrombus formation
- Occluding the coronary blood flow
- Resulting in ischaemia
What is a type 2 MI?
Include examples
- MI secondary to increased oxygen demand or reduced supply to the heard
- Imbalance may be caused by severe anaemia, hypotension, tachycardia
- Cocaine induced vasospasm
- Vasculitis
What is the pathophysiology of NSTEMI?
- Result of transient or near complete occlusion of the coronary artery
What is the clinical definition of an NSTEMI?
- **Chest pain **+ Rise in troponin **+ ECG changes but no ST segment elevation on ECG
What is the diagnostic investigation of NSTEMI?
Troponin levels
How are troponin results interpreted to confirm the diagnosis of NSTEMI?
0 hours troponin level
* > 1 hour of chest pain
Repeat troponin 1 hour after presentation
* If still low; Rule out NSTEMI
* High > 99th percentile of upper reference limit } confirm NSTEMI
What may FBC show in an NSTEMI?
FBC -
* Thrombocytopenia : NSTEMI increases the risk of bleeding, low platelets is a predictor of poor outcome
* Possible Type 2 MI ; secondary blood loss, anaemia
* Anaemia is common in NSTEMI as associated with increased mortality and major bleeding
What are the symptoms of clinical instability in an NSTEMI?
- On going recurrent chest pain
- Haemodyanmic instability } low BP/SHOCK
- Dynamic ECG changes
- LV failure
- Life threatening arrhythmia } VT or VF
What is the management of an UNSTEMI in an unstable patient?
- 12 lead ECG
- Urgent ECHO
If signs of acute heart failure in haemodynamic instability or cardiac arrest - Antiplatelet therapy - 300mg asprin
- Oxygen, GTN, morphine
- Immediate ICA with revascularision
Management of clinically stable patient
- Low risk : Conservative management
if symptoms of ischaemia develop } offer ICA - High or intermediate risk : ICA +/- Revascularisation within 72 hours
Post stabilisation of STEMI/NSTEMI
-
Anticoagulation
If no immediate ICA planned
- HASBLED
* Fondaprinux : 2.5mg subcutaneously for unto 8 days or till discharge
- Significant renal impairment creatinine >265 mcg } Unfractionated heparin isntead - Beta blocker - Bisoprolol 1.25mg OD initially for 1 week } increase gradually to max 10mg
3. Ace inhibitor
Enalapril 2.5mg OD initially / Ramipril 2.5mg BD for 3 days / lisinopril 2.5mg - 5 mg OD } gradually increase depending on response
Long term secondary prevention following UNSTEMI/STEMI
(6)
- **Continue Aspirin **75mg indefinitely
2.** Continue P2Y12 inhibitor** } 12 months
e.g. Ticagrelor 90mg BD / Clopidogrel 75mg OD
- **Beta blocker **} 12 months
- if LVEF reduced } lifelong - Ace inhibitor } life long
-
Aldosterone antagonist
- Signs of HF and reduced LVEF
- After starting ace inhibitor and 3-14 days post NSTEMI
6.** Statins **} all patients
80mg PO OD
MI : Secondary prevention life style advise
- Diet: advise a Mediterranean style diet,
* switch butter and cheese for plant oil based products.
2 . Exercise: advise 20-30 mins a day until patients are ‘slightly breathless’
* sexual activity may resume 4 weeks after an uncomplicated MI
What should be considered in patients with signficant LV dysfunction following MI?
- Patient with significant LV dysfunction ejection fraction of < 35%}
- consider implantable cardioverter defibrillator for primary and secondary prevention.
What are the complications of MI in < 48 hours
(2)
- Pericarditis - < 48 hours post MI
- VT/VF } majority occur within first 48 hours of admission
What does Bradycardia post MI indicate?
- Complete heart block - caused by damage to the RCA which supplies the AVN node
What are the complications of an MI?
(6)
- Cardiac arrest
- Cardiogenic shock - if a large part of ventricular myocardium is damaged
- Chronic heart failure
- Bradyarrhythmia - AV block following inferior myocardial infarctions
- Left ventricular aneurysm - ischaemic damage weaken the myocardium resulting in aneurysm formation.
- Acute mitral regurgitation - Common with infers-posterior infarction and may be due to ischaemia or rupture of papillary muscle.
Dressler’s syndrome - Incidence
2-6 weeks following an MI
Dressler’s syndrome - Etiology
Autoimmune reaction against injured myocardium as it recovers
Dressler’s syndrome - symptoms
Fever, pleuritic chest pain worse on inspiration and lying flat
Dressler’s syndrome - Investigation results
- Bloods : raised ESR
- ECG : Saddle shaped ST elevation +/- PR depression
Dressler’s syndrome - complication
Pleural effusion
Dressler’s syndrome - management
High dose NSAIDs
Left ventricular aneurysm - incidence
4 - 6 weeks post MI
Left ventricular aneurysm - investigation results
(2)
ECG : Persistent ST elevation
ECHO : LV failure
CXR : enlarged heart with bulge in left heart border
Left ventricular aneurysm - management
anticoagulation
Left ventricular aneurysm - incidence
Incidence : occurs in the first week after a MI attack
ACS : Antiplatelet therapy
- Aspirin (lifelong) & ticagrelor (12 months)
- If aspirin contraindicated, clopidogrel (lifelong)
PCI : Antiplatelet therapy
- Aspirin (lifelong) & prasurgrel or ticagrelor (12 months)
- If aspirin contraindicated, clopidogrel (lifelong)
TIA : Antiplatelet therapy
- Clopidogrel (lifelong)
- Aspirin (lifelong) & dipyridamole (lifelong)
Ischaemic stroke: Antiplatelet therapy
- Clopidogrel (lifelong)
- Aspirin (lifelong) & dipyridamole (lifelong)
Peripheral arterial disease: Antiplatelet therapy
- Clopidogrel (lifelong)
- Asprin (lifelong)
Clopidogrel : MOA
- antagonist of the P2Y12 adenosine diphosphate (ADP) receptor, inhibiting the activation of platelets
