Chapter 2 - ACS Flashcards
What syndromes does ACS include?
Unstable angina
NSTEMI
STEMI
What is the pathophysiology of ACS?
Build up of fatty deposits on the walls of coronary arteries
Plaque ruptures
Blood clot forms
How is ACS diagnosed?
Symptoms
Angiography
ECG
Troponin blood enzyme assay
What are the symptoms of ACS?
SOB Pain or discomfort in the chest that may radiate to the arm, jaw, neck, stomach, back Sweating Nausea Dizziness Lightheadedness Palpitations Feeling of impending doom
May also be indicated by stable angina that suddenly worsens, or prolonged angina at rest
Is there myocardial necrosis in unstable angina, NSTEMI, and STEMI?
UA - no
NSTEMI - yes (though less significant than STEMI)
STEMI - yes, irreversible
What is the initial management of unstable angina and NSTEMI?
300mg aspirin
Heparin
If needed:
O2
Pain relief (nitrates (buccal or IV, IV morphine or diamorphine)
Metoclopramide
Assess for angiography and possibly PCI
How are patients with unstable angina or NSTEMI assessed for angiography and PCI?
Assess the 6-month risk of mortality due to future adverse cardiovascular events
E.g. GRACE score
When is angiography and PCI carried out in unstable angina or NSTEMI?
If the patients condition is unstable - immediately
If the 6-month mortality is >3% - within 72 hours
What dual antiplatelet therapy should be given if PCI is carried out in unstable angina or NSTEMI?
Ticagrelor and prasugrel - if there is no separate indication for oral anticoagulation
Clopidogrel - if there is a separate indication for oral anticoagulation
What dual antiplatelet therapy should be given if PCI is not indicated in unstable angina or NSTEMI?
Ticagrelor - if there is a low risk of bleeding
Clopidogrel- if there is a high risk of bleeding
What is the initial management of STEMI?
300mg aspirin
Assess the patient for coronary reperfusion therapy (PCI or fibrinolysis)
How do you decide whether to do PCI or fibrinolysis?
Presenting with symptoms within 12h of onset and PCI available within 120 mins - PCI
Presenting with symptoms within 12h of onset and PCI NOT available within 120 mins - fibrinolysis
What dual antiplatelet therapy should be given if PCI is indicated?
Prasugrel - if there is no separate indication for oral anticoagulation
Clopidogrel - if there is a separate indication for oral anticoagulation
If the patient is over 75, dont use prasugrel, offer ticagrelor or clopidogrel
What treatment should be given if PCI is indicated in STEMI?
Dual antiplatelet therapy
Glycoprotein IIb/IIIa inhibitor (tirofiban or eptifibatide) plus:
Heparin if there’s radial access
Bivalirudin if femoral access is needed
What needs to be done 60-90 minutes after fibrinolysis in STEMI?
ECG
What other treatments might need to be considered if needed in STEMI?
Oxygen
Pain relief (nitrates (buccal or IV), or IV morphine/diamorphine
Metoclopramide (or cyclizine)
What drugs are used for the long term management of ACS?
Dual antiplatelet therapy
Beta blocker
ACEI/ARB
Statin
How long is dual antiplatelet continued for after ACS?
12 months
Then continue aspirin indefinitely
How long should beta-blockers be used for after ACS?
12 months
Unless there are other indications for beta-blockers e.g. HFrEF
What can be given as an alternative to beta-blockers for the long term management after ACS?
Verapamil
Diltiazem
How quickly should the dose of ACE Inhibitors be titration after ACS
Quickly - every 12-24h
The maximum tolerated dose should be reached by the time the patient leaves the hospital
What statin should be used after ACS?
Atorvastatin 80mg
What is the mechanism of action of aspirin?
It inhibits COX-1 enzymes
COX-1 enzymes are responsible for the production of thromboxane A2, which is a powerful promoter of platelet activation
It also reduces prostaglandin production, and so has an irritant effect on the stomach (may need a PPI)
What must be controlled before aspirin is initiated?
Blood pressure
What are the indications of aspirin?
Secondary prevention of CVD - 75mg OD
Treatment of TIA/ischaemic stroke - 309mg OD for 14 days
Treatment of angina, nSTEMI r STEMI - 300mg
Pain - 300-900mg every 4-6 hours, maximum 4g daily
Bypass surgery - 75-150mg OD
Precention of Pre-eclampsia in pregnancy in women at moderate to high risk - 75mg OD from 12 weeks gestation until birth
What are the contraindications of aspirin?
Active or history of a GI ulcer
Bleeding disorders
<16 years
Cautioned in asthma and hypertension
What are some side effects of aspirin?
Haemorrhage Menorrhagia Dyspepsia Dyspnoea Rhinitis
What are the indications of clopidogrel?
TIA/ischaemic stroke
After ACS alongside aspirin - initially 300mg then 75mg daily
Do clopidogrel, prasugrel or ticagrelor need to be discontinued before surgery?
Yes
Discontinue clopidogrel and prasugrel 7 days before surgery
Discontinue ticagrelor 5 days before surgery
What is the brand name of ticagrelor?
Brilique
How do fibrinolytics work?
They activate plasminogen to form plasmin
Which degrades fibrin and so breaks up the thrombus
How soon should antifibrinolytics be given after STEMI?
12 hours, although ideally within 1 hour
When is bivalirubin used?
This is a thrombin inhibitor
It is used as an anticoagulant for those undergoing ACS
In unstable angina/NSTEMI, if angiography and PCI are not planned in the next 24h, which heparin can be used?
Fondaparinux
Less than 24h - LMWH or UFH
What can rivaroxaban be used for in ACS?
Prophylaxis of atherothrombotic events following ACS with elevated cardiac biomarkers
Can be combined with aspirin or clopidogrel
