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Clinical Overview Clinical Overview of Atrial Fibrillationof Atrial Fibrillation

Edward L.C. Pritchett, M.D.Edward L.C. Pritchett, M.D.Consulting Professor of MedicineConsulting Professor of Medicine

Divisions of Cardiology and Clinical PharmacologyDivisions of Cardiology and Clinical Pharmacology

Duke University Medical CenterDuke University Medical CenterDurham, North CarolinaDurham, North Carolina

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Atrial Fibrillation PrevalenceAtrial Fibrillation Prevalence

• Most common sustained cardiac Most common sustained cardiac arrhythmiaarrhythmia11

• Most common diagnosis for Most common diagnosis for arrhythmia-related hospitalizationarrhythmia-related hospitalization22

• Estimated >2.3 million US adults have AFEstimated >2.3 million US adults have AF33

• Prevalence of AF increases with age and Prevalence of AF increases with age and with an aging populationwith an aging population44

11 Bialy D et al. Bialy D et al. J Am Coll CardiolJ Am Coll Cardiol 1992; 19-41A. 1992; 19-41A.22 Fuster V et al. Fuster V et al. CirculationCirculation 2006; 114:e257-e354 2006; 114:e257-e35433 Go AS et al. Go AS et al. JAMAJAMA 2001; 285:2370-2375. 2001; 285:2370-2375.44 Chug SS et al. Chug SS et al. J Am Coll CardiolJ Am Coll Cardiol 2001: 37:371-378 2001: 37:371-378

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Clinical Presentation of Clinical Presentation of Atrial FibrillationAtrial Fibrillation

• Atrial fibrillation is most commonly identified Atrial fibrillation is most commonly identified because patients have symptomsbecause patients have symptoms11

• The most appropriate use of antiarrhythmic The most appropriate use of antiarrhythmic drugs in patients with atrial fibrillation is for drugs in patients with atrial fibrillation is for relief of symptomsrelief of symptoms2,32,3

• Symptoms closely associated with occurrence Symptoms closely associated with occurrence of atrial fibrillation are palpitations, dyspnea, of atrial fibrillation are palpitations, dyspnea, chest pain, dizziness, asthenia, fatigue, chest pain, dizziness, asthenia, fatigue, nervousness, increased sweatingnervousness, increased sweating44

11 Psaty BM et al. Psaty BM et al. CirculationCirculation 1997;96:2455-2461. 1997;96:2455-2461.22 Page RL. Page RL. N Eng J MedN Eng J Med 2004;351:2408-2416 2004;351:2408-241633 Fuster V et al. Fuster V et al. CirculationCirculation 2006;114:e257-e354. 2006;114:e257-e354.44 Bhandari AK et al. Bhandari AK et al. Am Heart JAm Heart J 1992;124:381-386. 1992;124:381-386.

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Symptomatic Arrhythmias as an Outcome Symptomatic Arrhythmias as an Outcome in Antiarrhythmic Drug Approvals in Antiarrhythmic Drug Approvals

for Atrial Fibrillation and for Atrial Fibrillation and Other Supraventricular ArrhythmiasOther Supraventricular Arrhythmias

• 1986 verapamil PO IR - PSVT1986 verapamil PO IR - PSVT

• 1991 flecainide PO - PSVT, AF1991 flecainide PO - PSVT, AF

• 1996 ibutilide IV - AF1996 ibutilide IV - AF

• 1997 propafenone PO IR - PSVT, AF1997 propafenone PO IR - PSVT, AF

• 1999 dofetilide PO - AF1999 dofetilide PO - AF

• 2000 d,l sotalol PO - AF2000 d,l sotalol PO - AF

• 2003 propafenone SR PO - AF2003 propafenone SR PO - AFPritchett E, PACE, 1998;21:1457-1469.Pritchett E, PACE, 1998;21:1457-1469.

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Limitations of Current TherapiesLimitations of Current Therapies

Pharmacological Conversion withPharmacological Conversion withIV Antiarrhythmic DrugsIV Antiarrhythmic Drugs• Few choices of approved and labeled drugsFew choices of approved and labeled drugs• Imperfect efficacyImperfect efficacy• Adverse effects (ventricular arrhythmias)Adverse effects (ventricular arrhythmias)

Electrical CardioversionElectrical Cardioversion• Requires conscious sedationRequires conscious sedation• Complications (skin burns, aspiration, bradycardia, Complications (skin burns, aspiration, bradycardia,

ventricular arrhythmia)ventricular arrhythmia)• Inappropriate in some clinical situations Inappropriate in some clinical situations

(post-prandial, lung disease, recent cardiac surgery) (post-prandial, lung disease, recent cardiac surgery)

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Desirable Characteristics of Desirable Characteristics of Pharmacologic Converting AgentsPharmacologic Converting Agents

EfficacyEfficacy– High rate of restoring sinus rhythm High rate of restoring sinus rhythm

with relief of symptomswith relief of symptoms

– Rapid onset of action Rapid onset of action

SafetySafety– Low rate of adverse effectsLow rate of adverse effects

– Low incidence of drug interactionsLow incidence of drug interactions

– Lack of interference with electrical cardioversionLack of interference with electrical cardioversion