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ATRIAL FIBRILLATION.

Dr Murray F. Matangi MB ChB, FRACP, FRCPC, FACP, FACC
Cardiologist
Kingston Heart Clinic

                                                                                                     ·        PAROXYSMAL. Normal sinus rhythm interspersed with episodes of atrial fibrillation that typically self terminate.

PERSISTENT. Prolonged episodes of atrial fibrillation that are not self terminating, but can be cardioverted either chemically or electrically to restore sinus rhythm.

CHRONIC. Atrial fibrillation is constant, cardioversion may restore sinus rhythm but only for a brief period of time.

 Prevalence. 

             Increases with age,

·        0.4% of the adult population.

·        3% of those >60 years have atrial fibrillation.

·        13% of those  >75 years have atrial fibrillation.

Risk of atrial fibrillation by CV disease status.

·       Coronary disease                 5%

·       Hypertension                       9%

·       Congestive heart failure    25%

·       Rheumatic heart disease    35%

Lone atrial fibrillation.

 ·       Absence of potentially causative conditions.

·       Normal ventricular structure and function.

Atrial fibrillation, cardiac causes.

·       Hypertensive.

·       Ischemic heart disease.

·       Valvular heart disease.

·       Cardiomyopathy.

·       Pericarditis.

·       Cardiac tumours.

·       Post cardiac sugery.

Atrial fibrillation, non cardiac causes.

·       Pulmonary, COPD, Pneumonia, Pulmonary embolism, Sleep apnea.

·       Hyperthyroidism.

·       Alcohol, “holiday heart” syndrome.

·       Post-operative.

Treatment of acute atrial fibrillation.

          Initial questions.

·        Is this the first episode?

·        Duration of previous spells.

·        How symptomatic is the Patient?

·        How fast is the ventricular response.

·        Is the Patient hemodynamically stable?

·        Is there clinical evidence of pre-excitation?

Theraputic strategies.

·        Rate control.

o       Verapamil iv.

o       Propranolol iv.

o       Digoxin iv.

·        Atrial fibrillation termination.

o       Procainamide iv.

o       Propafenone po.

o       Amiodarone po.

o       DC cardioversion.

·        Prevention of atrial fibrillation recurrences.

o       Propafenone.

o       Amiodarone.

o       Sotalol.

o       Flecainide.

·        Anticoagulation. If atrial fibrillation has been <24hrs you may use DC shock without anticoagulation. If >48 hours or you are uncertain, then the Patient should be anticoagulated for 3-4 weeks before cardioversion and if the Patient converts to sinus rhythm the anticoagulation should continue for a further 3-4 weeks after cardioversion.

Chronic treatment of atrial fibrillation. 

·        Prevention of recurrences.

o       Antiarrhythmic drugs.

o       Curative catheter ablation procedures.

o       MAZE procedure.

·        Recurrence rate

o       50% within 1 year will revert back to atrial fibrillation. The recurrence rate is possibly lower with amiodarone.

Treatment of Chronic atrial fibrillation. 

·        Control of ventricular rate.

o       Drugs, Propranolol, verapamil, anmiodarone.

o       AV nodal ablation and VVIR pacemaker.

·        Anticoagulation.

o       Coumadin, INR 2-3.

  END.