General management and drug prevention of paroxysmal atrial fibrillation
THE CONTEXT
Management of atrial fibrillation (AF) depends on its persistence, precipitating factors and symptoms. Stroke risk stratification and prevention remain central.
Initial management
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Weight loss in obesity, reducing or abstaining from alcohol, and treating hypertension, heart failure and sleep apnoea improve the chances of maintaining sinus rhythm.
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When AF complicates an acute illness such as chest infection or pulmonary embolism, treating the underlying disorder often restores sinus rhythm.
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If AF persists, management involves choosing rate control or rhythm control. Occasional, well-tolerated paroxysmal attacks do not require treatment.
Drugs for paroxysmal AF
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Beta-blockers are normally first-line therapy: they reduce initiating ectopic firing and control the ventricular rate. They are particularly useful with coronary artery disease, hypertension or cardiac failure.
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Propafenone and flecainide are effective class Ic drugs but should not be given to patients with coronary artery disease or left ventricular dysfunction.
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Flecainide can precipitate atrial flutter and is usually prescribed with a rate-limiting beta-blocker.
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Amiodarone is the most effective preventive agent, but side-effects restrict its use to cases where other measures fail.
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Dronedarone is an effective alternative but is contraindicated in heart failure or significant left ventricular impairment.
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Diltiazem, at 200–400 mg daily, is sometimes used to prevent AF but is less effective.