Acute coronary syndrome

• There are 3 types of Acute coronary syndrome:

  1. Unstable angina
  2. STEMI
  3. NSTEMI
• ACS happens when there is a blockage in a coronary artery due to an atherosclerotic plaque which forms a thrombus.
• The right coronary artery supplies:

  1. Right atrium
  2. Right ventricle
  3. Posterior septal area
  4. Inferior aspect of left ventricle
• Left coronary artery divides into:

  1. Circumflex artery
  2. Left anterior descending artery
• LCA > Circumflex branch supplies:

  1. Left atrium
  2. Posterior aspect of left ventricle

  LCA > LAD supplies:

  1. Anterior aspect of left ventricle
  2. Anterior aspect of septum
• How does ACS present?

  • Central constricting chest pain
  • Radiating to jaw or arms
  • Nausea and vomiting
  • Sweating and clammy
  • Impending doom
  • Shortness of breath
  • Palpitations
• ACS symptoms continue at rest for more than 15 minutes.
• ECG changes:

  STEMI:

  • ST elevation
  • New Left bundle branch block

  NSTEMI:

  • ST depression
  • T wave inversion

  Pathological Q waves suggest transmural infarction which appears 6 or more hours after onset of symptoms.
• What generic area of the heart is affected by left coronary artery thrombus? and which leads show changes on ECG?

  Anterolateral

  I, aVL, V3-6
• What generic area of the heart is affected by LAD thrombus? and which leads show changes on ECG?

  Anterior wall; Leads V1-V4.
• What generic area of the heart is affected by circumflex thrombus? and which leads show changes on ECG?

  Lateral

  I, aVL, V5-6
• What generic area of the heart is affected by right coronary artery thrombus? and which leads show changes on ECG?

  Inferior

  II, III, aVF
• What is troponin used to diagnose?

  NSTEMI
• A rise in troponin is consistent with myocardial ischaemia
• STEMI is diagnosed by clinical presentation and ECG findings.
• Repeat troponin tests should be done:

  • At baseline
  • 3 hours post-onset of symptoms
• A high troponin or a rising troponin indicates an NSTEMI
• Troponin can be raised in:

  • ACS
  • CKD
  • Sepsis
  • PE
  • Aortic dissection
  • Myocarditis
• Investigations which should be done in a patient with suspected ACS:

  • Troponin
  • FBC
  • U&E
  • LFT
  • Lipids
  • Glucose
  • Echocardiogram
• An echocardiogram should be done in suspected ACS workup to assess functional damage to the heart and look at left ventricular function.
• STEMI classification:

  ECG - ST elevation, New Left bundle branch block
• NSTEMI classification:

  Raised troponin

  With either...

  Normal ECG or ST depression/T-wave inversion
• Unstable angina classification:

  Normal troponin and either...

  Normal ECG or ST depression/T-wave inversion
• The difference between NSTEMI and unstable angina is troponin levels. In NSTEMI there will be a raised troponin, in unstable angina troponin will be normal.
• What is the initial management of ACS?

  C - call and ambulance

  P - perform an ECG

  A - aspirin 300mg

  I - IV morphine and Metaclopramide

  N - Nitrate (GTN)
• How do you manage a STEMI?

  If presenting within 12 hours:

  Percutaneous coronary intervention - give aspirin and prasugrel before

  Thrombolysis if PCI not available within 2 hours - fibrinolytic agent - alteplase
• What is the management of NSTEMI?

  B - Base the decision about PCI on the GRACE score

  A - Aspirin 300mg

  T - Ticagrelor 180mg

  M - Morphine

  A - Antithrombin therapy with fondaparinux

  N - Nitrate (GTN)
• What is the GRACE score?

  The GRACE score gives the probability of death within 6 months post-NSTEMI. Less than 3% is classed as low risk. More than 3% is classed as medium to high risk and in these patients they would be considered for PCI within 72 hours.
• What are the 6 A's of secondary prevention?

  Aspirin

  Another antiplatelet such as ticagrelor or clopidogrel for 12 months

  Atorvastatin 80mg once daily

  ACE inhibitors such as ramipril

  Atenolol or bisprolol

  Aldosterone antagonists such eplerenone
• Why is it important to monitor renal function in those post-MI?

  Secondary prevention involves ACE inhibitors and aldosterone antagonists which can cause hyperkalaemia.
• What are 5 complications of MI?

  D - Death

  R - Ruptured heart septum or papillary muscles

  E - oEdema (heart failure)

  A - Arrhythmia and Aneurysm

  D - Dressler's syndrome
• What is Dressler's syndrome?

  Dressler's syndrome is also known as post-MI syndrome. It happens as a localised immune response which causes inflammation of the pericardium. Also known as pericarditis.
• What are the 4 types of MI?

  Type 1 - ACS type MI

  Type 2 - Can't cope MI - secondary to increased demand

  Type 3 - Death by MI - sudden cardiac death

  Type 4 - Caused by us MI - post-PCI, CABG, stent