Angina/Acute Coronary Syndrome Flashcards
What comprises IHD?
- ACS (unstable angina, NSTEMI and ST)
- Stable angina
When does maximum coronary blood flow occur?
Diastole
Which area of the heart is most vulnerable to ischemia?
Subendocardial area
Myocardial wall pressure is greatest in this area which is closest to LV cavity
In which direction is the hear perfused?
Epicardial to Endocardial
In which direction is the heart depolarised?
Endocardium to Epicardium
List the 4 types of MI
- Type 1: Traditional MI due to acute coronary event
- Type 2: Ischaemia 2o to increased demand or reduced supply of oxygen (eg. 2o 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
List 2 non-modifiable risk factors for IHD
- Increasing age
- Male; females catch up after menopause
- FxH of premature (<60 years) CAD
List 2 modifiable risk factors for IHD
- Smoking
- Hyperlipidaemia
- Diabetes - doubles risk
- Hypertension
What is Angina?
Narrowing of coronary arteries reduces blood flow to the myocardium during times of high demand (ie. exercise)
Results in insufficient supply to meet demand
How does Angina present?
Constricting chest pain with or without radiation to jaw or arms
What defines ‘stable’ angina?
Chest pain typical of angina is defined by:
- Constriction like pain in chest/neck/arm/jaw
- Brought on by physical activity
- Alleviated by rest or GTN within minutes
2/3 features indicate atypical angina pain
What defines ‘unstable’ angina?
When the symptoms come on randomly whilst at rest
What is the First line investigation for angina?
CT Coronary Angiography (CTCA) - Gold Standard
Involves injecting contrast and taking CT images to highlight any narrowing
When is CTCA indicated for Angina?
For atypical or typical angina pain or
ECG shows ischaemic changes in chest pain with < 2 angina features
List the second and third line investigations for stable Angina
2nd line: non-invasive functional imaging
3rd line: invasive coronary angiography
List 3 examples of Non-invasive functional imaging
- Myocardial perfusion scintigraphy with SPECT
- Stress ECHO
- MRI for regional wall motion abnormalities
List 4 other baseline investigations for Angina
- Physical Examination
- ECG
- FBC (check for anaemia)
- U&Es (prior to ACEi and other meds)
- LFTs (prior to statins)
- Lipid profile
- TFTs
- HbA1C and fasting glucose
What are the 4 principals of Angina management (RAMP)
- Refer to cardiology (urgently if unstable)
- Advise patient about diagnosis, management and when to call an ambulance
- Medical treatment
- Procedural or surgical interventions
First line treatment for stable Angina?
Beta blocker or rate limiting CCB
If not tolerated or symptoms not controlled, try switching to the other from above
Second line treatment of stable angina?
Beta blocker + long-acting dihydropyridine CCB
Third line treatment for Stable Angina?
Monotherapy with one of the following anti-anginals:
- Ivabradine
- Nicorandil
- Ranolazine
- Isosorbide mononitrate
What procedure may patients with stable angina be eligible for?
What is the criteria for this
Re-vascularisation (with CABG or PCI) if:
- symptoms are not controlled on optimal medical treatment AND
- there is complex 3 vessel disease or
- there is significant left main stem stenosis
What causes ACS?
Thrombus from an atherosclerotic plaque blocking a coronary artery
How is a diagnosis of ACS made?
ECG + serial troponins
How is a diagnosis of STEMI made?
If there is ST elevation or new left bundle branch block on ECG
Must be in 2 consecutive leads (2 in chest, 1 limb)
How is a diagnosis of NSTEMI made?
Raised troponin levels and/or
Other ECG changes (ST depression or T wave inversion or pathological Q waves)
List 2 possible diagnosis if there are normal troponin levels and normal ECG
- Unstable angina
- Musculoskeletal chest pain
How does ACS present?
Central, constricting chest pain associated with:
- Nausea and vomiting
- Sweating and clamminess
- Feeling of impending doom
- SOB
- Palpitations
- Pain radiating to jaw or arms
What duration must symptoms persist to be regarded as ACS?
> 20 minutes
Which patient group may not experience typical chest pain
Diabetics - “Silent MI”
List 2 ECG changes seen in STEMI
- ST elevation in leads consistent with an area of ischaemia
- New Left Bundle Branch Block
List 3 ECG changes which may be seen in an NSTEMI
- ST segment depression
- Deep T Wave Inversion
- Pathological Q Waves (suggests deep infarct - late sign)
State which artery supplies each heart area and which are the corresponding ECG leads
List 5 investigations for ACS (not bloods)
- ECG
- CTCA - assess CAD
- Chest xray - for ddx
- Physical Examination
List 4 things to investigate on bloods for ACS
- FBC (check for anaemia)
- U&Es (prior to ACEi and other meds)
- LFTs (prior to statins)
- Lipid profile
- TFTs
- HbA1C and fasting glucose
List 2 other causes of raised troponins (not ACS)
- Chronic renal failure
- Sepsis
- Myocarditis
- Aortic dissection
- Pulmonary embolism
What is the definitive treatment for an acute STEMI
Presenting within 12hrs of onset
- Primary PCI (if available within 2 hours of presentation)
- Thrombolysis (if PCI not available within 2 hours)
What is PCI?
Catheter inserted via brachial or femoral artery into coronary arteries under xray guidance. Contrast injected to identify blockage
Treated with balloons to widen the gap or devices to remove or aspirate the blockage
Usually stent is put in to keep the artery open
What is Thrombolysis?
What is the risk
Use of fibrinolytic medication that rapidly dissolves clots
Significant risk of bleeding
List 2 examples of Thrombolysis
- Streptokinase
- Alteplase
- Tenecteplase
What is the treatment of an Acute NSEMI?
MONA
- Grace score ≤ 3 → Ticagralor and Fondapainux
- Grace score > 3 → PCI (give Prasugrel or Clopidogrel prior)
Should O2 be routinely given in NSTEMI treatment?
NO, only if O2 sats are dropping (ie. <95%).
What score is used to assess for PCI in NSTEMI
GRACE Score
Gives a 6-month risk of death or repeat MI after having an NSTEMI
Interpret the GRACE score and state who is eligible for PCI?
- <5% Low Risk
- 5-10% Medium Risk
- >10% High Risk
Medium or high risk are considered for early PCI (within 4d of admission) for underlying CAD
List 4 complications of an MI
(DREAD)
- Death
- Rupture of the heart septum or papillary muscles
- “Edema” (Heart Failure)
- Arrhythmia and Aneurysm
- Dressler’s Syndrome
What is Dressler’s Syndrome? (ie. post MI syndrome)
How does it present?
Pericarditis which occurs 2-3 wks post MI
Presents with pleuritic chest pain, low grade fever and a pericardial rub on auscultation
List 2 complications of Dressler’s syndrome
pericardial effusion and pericardial tamponade
How is a diagnosis of Dressler’s syndrome made?
- ECG (global ST elevation and T wave inversion),
- Echocardiogram (pericardial effusion)
- Raised inflammatory markers (CRP and ESR)
Management of Dressler’s syndrome
NSAIDs (aspirin / ibuprofen), more severe require steroids (prednisolone)
May need pericardiocentesis to remove fluid
List the 6 secondary prevention medical managements for ACS
(6A’s)
- Aspirin
- Another antiplatelet: eg. clopidogrel or ticagrelor
- Atorvastatin
- ACEi
- Atenolol (or other BB)
- Aldosterone antagonist
List 4 secondary lifestyle prevention measures
- Stop smoking
- Reduce alcohol consumption
- Mediterranean diet
- Cardiac rehabilitation
- Optimise treatment of other medical conditions (e.g. diabetes and hypertension)
