Management of Atrial Fibrillation After Coronary Artery Bypass Graft

1
Management of Atrial Fibrillation After Coronary
Artery Bypass Graft

• ??????
• 90-9-3

2
Epidemiology

• 20-30 of CABG pt having clinically important A
  fib that requires intervention
• high riskelderly males,the number of graft
  implantations,left internal mammary artery bypass
  grafting,longer aortic cross clamp time

3
Presentations

• In the first 3 dayspersistent,recur at frequent
  intervals,rapid ventricular response
• after 3 days less rapid ventricular response ,
  usually better tolerated
• after 2-3 days incidence 25-45

4
Etiology and mechanisms(1)

• Pericarditis from trauma and inflammation of
  surgery and cannulation
• autonomic disruptions from surgery
• ischemic injury
• the residual effect of cardioplegia and
  cardiopulmonary bypass
• postoperative hemodynamic changes and fluid shifs

5
Etiology and mechanisms(2)

• Post surgical effects on previously damaged
  myocardial tissure
• CABG can increase both epinephrine and
  norepinephrine levels(A fib occurs)

6
Consequences

• Compromised cardiac function
• stroke and thromboembolism(2 to 3 -fold)
• longer hospitalizations and longer costs(16)
• adverse effects from the therapy itself(exearly
  DC cardioversion?bradycardia,tachycardia,myocardia
  l damage)

7
Management(1)

• ProphylaxisMGSO4,antiarrhythmic
  drugs,?-adrenergic blockers
• ventricular rate control ?-adrenergic blockers
  ,digoxin(poor left ventricular function or heart
  failure),diltiazem,verapamil

8
Management(2)

• Procainamide Procainamide 25mg/min?conversion
  rate 87 over 40mins,36 had recurrent A fib
• digoxindigoxin 0.75-1.0mg ?conversion rate 60
  over 540 mins,22 had recurrent A fib

9
Management(3)

• Propafenone and sotalolthe drug is not available
  in iv form in the US
• Aminodarone (2.5-5mg/kg) not be highly effective
  therapy, ,only 1 of 15 aminodarone-treated pt
  and 2 of 15 digoxin-treated pt reverted to sinus
  rhythm in 24hrs ,but FDA approval of
  ivAminodarone is increase the use of this agent
  in pt with post CABG A fib

10
Management(4)

• Disopyramide(2mg/kg)48 reversion to sinus
  rhythm ,side effectsventricular tachycardia and
  urinary retention

11
Hemodynamic unstable
Hemodynamic stable
cardioversion
Rate control
recurrent
persists
Consider heparin
stop
Antiarrhythmic drug
recurrent
ineffective
effective
cardioversion
recurrent
Rate control
Continus drugs 4 to 6 weeks
coumadin