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

Aspirin with Clopidogrel is an option for patients with atrial fibrillation that can not take Warfarin

The ACTIVE-A randomised patients with AF and who were not eligible for oral anticoagulant therapy, or who declined oral anticoagulant therapy, and who had and at least one risk factor for thromboembolism to Aspirin alone vs Aspirin plus Clopidogrel.The findings were published in the New England Journal of Medicine on 31/3/2009 (volume 360).

The mean patient age and risk factor status was similar to patients enrolled in the ACTIVE-W trial. The mean age was approximately 70 years with a mean CHADS2 score of 2.

There was a non-significant reduction of the primary outcome (stroke, myocardial infarction, non-CNS systemic embolism, vascular death). The primary event rate was 7.6% per year in the Aspirin alone group vs 6.8% in the Aspirin plus Clopidogrel group.

The stroke rate was 3.3% per year in the Aspirin alone group and 2.1% per year in the Aspirin plus Clopidogrel group (p<0.001). Interestingly, the rate of myocardial infarction was also lower in the combination therapy group. There were no differences in the rates of vascular death or non-CNS systemic embolism.

The rates of non-CNS systemic embolism was 0.4% per year vs a stroke rate of 3.3% per year in the Aspirin alone group. Possible explanation include a higher risk of CNS embolism in those with AF or that non-CNS emboli are more often silent and do not cause symptoms.

Almost two thirds of the strokes were classifed as being disabling.

Major bleeding rates were higher in the combination therapy group (2.0 percent per year) vs the Aspirin alone group (1.3% per year).

One thousand patients treated for three years with Aspirin and Clopidogrel would
• prevent 28 fatal or disabling stroke
• prevent 6 myocardial infarcts
• cause 20 non-stroke major bleeding and of these three episodes of major bleeding would be fatal.

Another way to express these small benefits and risks is (as expressed in the editorial in the NEJM) to state that combinatin therapy:
• prevents on disabling or fatal stroke for every 200 patients treated for one year.
• causes one extra major haemorrhagic bleeding episode for every 143 patients treated for one year.
• causes one extra intracranial haemorrhagic stroke for every 500 patients treated for one year.

Hitesh Patel
June, 2009