Atrial Fibrillation

• Issues in Management of AF

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• Should We Maintain Sinus Rhythm?
• The AFFIRM trial
• The SAFE-T trial- amiodarone vs sotalol vs placebo

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• Anticoagulation in AF
  • Risk of Thromboembolism-CHADS2
  • "Moderate Risk" Patients
  • "High-Risk" Patients
  • Secondary Prevention
  • Target INR level for AF patients
  • Maintain INR in theurapeutic range

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• Clopidogrel
  • Anticoagulation slightly better than Clopidogrel with Aspirin
  • Clopidogrel with Asprin better than Aspirin alone for those not eligible for anticoagulation

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• Cardioversion
• Role of Transoesophageal Echo in Cardioversion

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• Use of ACE-inhibitors or ARBs
• ACE-inhibitors may reduce the risk of recurrent PAF in those with lone PAF

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• Non-Pharmacological Therapy
• Options

Non-pharmacological therapies for AF

• Dual site atrial pacing:This option does not seem to have stood the test of time.
  
  This involves implantation of a pacemaker with two atrial leads, one in the high right atrium and the other in the coronary sinus or its tributaries to pace the left atrium. Two of the potential mechanisms of action of biatrial pacing are suppression of atrial ectopics and prevention of atrial pauses, both of which can trigger atrial fibrillation.


• Pulmonary vein ablation: Atrial fibrillation can be triggered by atrial ectopic beats arising from the ostia of the pulmonary veins. Ablating these ostia has been reported to be successful in preventing atrial fibrillation. The procedure is quite challenging and there are associated risks such as pulmonary venous perforation and stroke and late stenosis at the site of ablation.
• The MAZE procedure: This procedure can be performed surgically or with a catheter based technique. Lesions are created to form electrical barriers to prevent maintenance of atrial fibrillation.
• Atrio-ventricular node ablation: In some patients with uncontrollable and very symptomatic paroxysmal or chronic atrial fibrillation the atrio-ventricular node is ablated and a permanent pacemaker implanted. By this means, at least the ventricular rate can be controlled even if the patient remains in chronic atrial fibrillation or continues to have paroxysmal atrial fibrillation.

Presumably, before invasive treatment for a common disorder is widely accepted, we need to await results of more studies, and in particular, whether prevention of atrial fibrillation by this technique reduces mortality. In the meantime, use of these techniques will always be influenced by local resources and expertise, and also on individuals' interpretation of the data.

Pulmonary vein ablation is now being performed in Auckland. The MAZE procedure is done at the time of cardiac surgery in some patients. AV node ablation and permanent pacemaker therapy is available for the rare patient for whom this remains the only option. Obviously, consultation with the electrophysiology service is necessary.