Diagnosis and management of Acute Coronary Syndromes - NSTEMI and Unstable angina Flashcards
What is acute coronary syndrome
Spontaneous plaque rupture leading to local thrombosis, with degrees of occlusion in the coronary artery
What components make up acute coronary syndrome
Unstable angina
NSTEMI
STEMI
Sudden cardiac death
What factors is important in deterring platelet stability
inflammation
Sheer stress
What is the differing symptoms of ACS compared to stable angina
Symptoms are occurring at rest
What is the history In diagnosing ACS
Site of pain: retrosternal
Character of pain: often tight band/pressure/heaviness.
Radiation sites: neck and/or into jaw, down arms.
Aggravate with exertion
incomplete improvement with GTN, or physical rest; and/or ongoing.
What is the modifiable risk factors for ACS
Smoking Diabetes mellitus Hyperlipidaemia Hypertension Lifestyle- exercise & diet
What is the history in unstable angina diagnosis
angina originally only happened on exertion
Now progressively increasing in frequency and severity, Until provoked by less exertion and/or then at rest
What is the history in NSTEMI diagnosis
more often start with myocardial ischaemic symptoms i.e. angina occurring at rest
What is the clinical signs of NSTEMI and unstable angina that could be seen on examination
May look very unwell or May look completely fine
Often no specific features to find
Monitor: HR, BP
Listen for murmurs, crackles in chest
What can potentially be seen in an ECG of NSTEMI and unstable angina
may be normal, but:
commonly ST-segment depression, transient ST-segment elevation and/or T-wave inversion;
When can changes be seen in an ECG for unstable angina vs NSTEMI
ECG returns to normal after the pain has went away in unstable angina however persists in NSTEMI - but not always
What is problems that occur in making the diagnosis
Typical symptoms not always present
Atypical presentation can arise (missing core features)
What patients are likely to present atypical presentation of ACS and why
women the elderly or diabetics as are all influenced by reduced pain sensation
What are the cardiac biomarkers of unstable angina and NSTEMI and h
cardiac troponin (cTn)
if it becomes detectable it means there is damage (as cells wall is leaking them)
therefore acts as sensitive and specific marker of cardiac myocyte damage.
What is the limiting factor in cardiac troponin biomarker
Doesn’t define source or site of damage
not all troponin elevations are a ACS and caused by atherothrombosis
What is the immediate treatment plan for unstable angina and NSTEMI
Morphine (or diamorphine)
Oxygen
Nitroglycerine (GTN spray or tablet)
Aspirin 300 mg orally (crush/chew)
What is dual anti-platelet therapy that all ACS patients should receive one year after the event
both aspirin and a ADP receptor blocker
What is examples of ADP receptors blockers and their dosage
Clopidogrel: Bolus 300mg and 75mg daily.
Prasugrel: Bolus 60mg and 10mg daily.
Ticagrelor: Bolus 180mg and 90mg BD daily
What is examples of Anti-thrombotic therapy in unstable angina and NSTEMI
Intravenous unfractionated heparin (UFH) or s/c low molecular weight heparin (LMWH)
Fondaparinux (new)
Why is LMWH better than UFH
improved clinical outcome, is easier to administer: given subcutaneously and not need to be monitored
When are beta blockers recommend in the treatment of unstable angina and NSTEMI
and what is the purpose of beta blocker treatment
in the absence of contraindications - asthma, acute left ventricular dysfunction, impaired AV nodal conduction
To reach target heart rate should be between 50 and 60 bpm and reduce the myocardial oxygen demand
What is the benefit of statin in the treatment of unstable angina and NSTEMI
reduces plaque acutely therefore chronically reduce further events
When would ACE inhibitors be used the treatment of unstable angina and NSTEMI
if left ventricular dysfunction is present
is controversial if normal function
What patients receive Coronary revascularisation treatment
High risk patients - benefit from invasive strategy compared to medical treatment
What coronary revascularisation procedures can be performed in unstable angina and NSTEMI
coronary angiography and revascularisation by PCI CABG
What is the time frame for coronary revascularisation procedure to prevent reoccurrence
PCI - as soon as possible
CABG- within 3-12 hours
what is the process of coronary angiography and revascularisation by PCI
Coronary guided wire advances to atherosclerotic plaque,
ballon is slide over the wire and inflated to compress the plaque and open the construction,
stent is then placed in the dilated area,
Balloon expands and deploys the stent
The catheter is then removed
