Table 3.

Rate and Rhythm Control Agents Used in Atrial Fibrillation

Medication	Mechanism of action	Risk of QT prolongation*	Contraindications†
Rhythm control
Flecainide	Sodium channel blockade	Known	Structural heart disease, ischaemic heart disease
Disopyramide	Sodium channel blockade	Known	Narrow-angle glaucoma, decompensated heart failure
Propafenone	Sodium channel blockade	Conditional	Heart failure, ischaemic heart disease asthma, severe COPD,
Sotalol	Beta adrenoreceptor and potassium channel blockade	Known	Asthma, renal impairment (creatinine clearance < 40 mL/min), decompensated heart failure
Amiodarone	Primarily potassium channel blockade, but also has sodium and calcium channel blocking properties	Conditional	Iodine hypersensitivity. Must be used cautiously in the context of pulmonary, thyroid or hepatic disease due to risk of toxicity to these organs.
Rate control
Atenolol, metoprolol	Beta adrenoreceptor blockade	Not associated	Asthma, hypotension
Verapamil, diltiazem	Calcium channel blockade	Not associated	Heart failure, hypotension
Digoxin	Inhibition of the sodium/potassium/ATPase pump	Not associated	Hypokalaemia, must be used cautiously in renal impairment due to risk of toxicity

COPD, chronic obstructive pulmonary disease; ATP, adenosine triphosphate

*Severe bradycardia can be caused by any of these agents, and QT prolongation can occur in this context

^†All agents listed are contraindicated in the presence of sinus node dysfunction or severe conduction disease, e.g. second- or third-degree AV block, or bifascicular and trifascicular block