Atrial Fibrillation

• What are the reversible causes of AF?


  SMITH

  Sepsis

  Mitral valve pathology

  IHD

  Thyrotoxicosis

  HTN
• What is atrial fibrillation?


  Disordered pattern of atrial contraction
• Pathophys of AF


  Electrical activity becomes disorganised → contraction of atria become uncoordinated, rapid & irregular which overrides regular, organised activity from SAN & passes through ventricles → irregularly irregular ventricular contraction

  Uncoordinated atrial activity → blood can stagnate in atria & form thrombus → thrombus in LA may travel to brain & block cerebral artery → ischaemic stroke
• Risk of stroke is 5x higher in pts with AF.
• What are the different types of AF?


  Paroxysmal

  • self-terminating, usually within 48 hours
  • may last up to 7 days
  • may recur with variable frequency

  Persistent

  • longer than 7 days (inc. episodes for a year or more)
  • not self-termination, require pharmacological or electrical cardioversion for termination

  Long-standing persistent

  • pts who have been in continuous AF for a year or more

  Permanent

  • presence of arrhythmia accepted by pt & clinician
  • rhythm control strategies are no longer pursued
• What are the Inx for AF?


  Obs

  Full Hx & examination

  ECG

  Bloods (FBC, U&Es, LFTs, TFTs, CRP, Coag, bone profile, ?troponin)

  CXR

  Echo
• What will AF show on an ECG?


  No discernable P waves

  Irregularly irregular rhythm
• What are the RFs of AF?


  Increasing age

  Male

  HTN

  IHD

  HF

  Cardiomyopathy

  Diabetes mellitus

  Obesity

  Pneumonia

  Smoking

  OSA

  Thyrotoxicosis

  Caffeine

  Alcohol excess

  CKD
• What are the signs & symptoms of AF?


  Asymptomatic (mostly)

  Palpitations

  SOB

  Dizziness/syncope

  Exercise intolerance

  Irregularly irregular pulse

  Signs & symptoms of any associated conditions
• What are the possible complications of AF?


  Stroke (most common)

  MI

  HF
• What are the treatments for AF?


  Rhythm control

  • cardioversion
  • amiodarone, flecainide
  • DC cardioversion
  • ablation
  • long-term rhythm control
  • beta blockers
  • dronedarone
  • amiodarone

  Rate control

  • beta blocker
  • Ca+2 channel blocker
  • digoxin
  • amiodarone

  Anticoagulation

  • DOACs
  • warfarin
• When is rhythm control used in AF?


  New AF (within last 48 hours)

  Haemodynamic instability
• What should be used to decide if a pt with AF needs anticoagulation?


  CHA2DS2VASc Score

  
• What can be used to find out bleeding risk in AF?


  ORBIT score