Acute Coronary Syndrome Flashcards
What is the cause of acute coronary syndrome?
-thrombus from an atherosclerotic plaque blocking a coronary artery.
-When a thrombus forms in a fast flowing artery it is made up mostly of platelets.
What are the three types of coronary syndrome?
Unstable Angina
ST Elevation Myocardial Infarction (STEMI)
Non-ST Elevation Myocardial Infarction (NSTEMI)
How is it diagnosed ?
- symptoms then do ECG
- ST elevation -> STEMI diagnosis
-No ST elevation-> troponin blood test. If troponin raised or ECG changes then NSTEMI. (ST depression, T wave inversion)
If normal troponin and ECG then unstable angina or MSK chest pain.
Symptoms?
Nausea and vomiting
Sweating and clamminess
Feeling of impending doom
Shortness of breath
Palpitations
Pain radiating to jaw or arms
How does the ECG change in a STEMI and NSTEMI
STEMI:
ST segment elevation in leads consistent with an area of ischaemia
New Left Bundle Branch Block also diagnoses a “STEMI”
NSTEMI:
ST segment depression in a region
Deep T Wave Inversion
Pathological Q Waves (suggesting a deep infarct – a late sign)
What kind of troponins are used to diagnose ACS?
Serial troponins
What are the alternative causes of raised troponin than ACS ?
Chronic renal failure
Sepsis
Myocarditis
Aortic dissection
Pulmonary embolism
What investigations would you carry out?
Same for stable angina + chest x ray, echocardiogram, CT coronary angiogram
How do we treat acute STEMI?
PCI- catheter into brachial or femoral, inject contrast and treat with balloons to widen gap and stent.
Thrombolysis- inject fibrinolytic medication, dissolve clots e.g streptokinase, alteplase and tenecteplase.
How do we treat an acute NSTEMI?
B – Beta-blockers unless contraindicated
A – Aspirin 300mg stat dose
T – Ticagrelor 180mg stat dose (clopidogrel 300mg is an alternative if higher bleeding risk)
M – Morphine titrated to control pain
A – Anticoagulant: Fondaparinux (unless high bleeding risk)
N – Nitrates (e.g. GTN) to relieve coronary artery spasm
Complications of MI
D – Death
R – Rupture of the heart septum or papillary muscles
E – “Edema” (Heart Failure)
A – Arrhythmia and Aneurysm
D – Dressler’s Syndrome
What is dressler’s syndrome and how is it managed ?
It usually occurs around 2-3 weeks after an MI. It is caused by a localised immune response and causes pericarditis (inflammation of the pericardium around the heart).
It presents with pleuritic chest pain, low grade fever and a pericardial rub on auscultation. It can cause a pericardial effusion and rarely a pericardial tamponade (where the fluid constricts the heart and prevents function).
A diagnosis can be made with an ECG, echocardiogram (pericardial effusion) and raised inflammatory markers (CRP and ESR).
Management is with NSAIDs (aspirin / ibuprofen) and in more severe cases steroids (prednisolone). They may need pericardiocentesis to remove fluid from around the heart.
What is the secondary medical prevention of ACS?
Aspirin 75mg once daily
Another antiplatelet: e.g. clopidogrel or ticagrelor for up to 12 months
Atorvastatin 80mg once daily
ACE inhibitors (e.g. ramipril titrated as tolerated to 10mg once daily)
Atenolol (or other beta blocker titrated as high as tolerated)
Aldosterone antagonist for those with clinical heart failure (i.e. eplerenone titrated to 50mg once daily)
What are the secondary lifestyle preventions for ACS?
Stop smoking
Reduce alcohol consumption
Mediterranean diet
Cardiac rehabilitation (a specific exercise regime for patients post MI)
Optimise treatment of other medical conditions (e.g. diabetes and hypertension)
What are the types of MI?
Type 1: Traditional MI due to an acute coronary event
Type 2: Ischaemia secondary to increased demand or reduced supply of oxygen (e.g. secondary to severe anaemia, tachycardia or hypotension)
Type 3: Sudden cardiac death or cardiac arrest suggestive of an ischaemic event
Type 4: MI associated with PCI / coronary stunting / CABG
