Table 5

Pharmacotherapy options: A) Rate control; B) Rhythm control.

β-blockers (β-1 cardioselective)
  • Metoprolol (Lopresor, regular and SR)

  • 25-200 mg BID or 100-200 mg SR OD to BID

  • First-line agents in patients with comorbid conditions such as CAD, HF, or LV dysfunction

  • Generally well tolerated

  • Dizziness or fatigue often reported as bothersome side effects

  • Use cautiously in elderly patients (fall risk)

  • Can mask hypoglycemia (use cautiously in diabetes)

  • $10-$33

  • Bisoprolol (Monocor)

  • 2.5-10 mg OD

  • Effective for rate control at rest and with exercise, but no remarkable effects on exercise capacity

  • $10-$15

Nondihydropyridine CCBs
  • Diltiazem (Cardizem, regular and CD; Tiazac, regular and XC)

  • 120-480 mg OD

  • Preferred for younger patients (less fatigue than with β-blockers)

  • Preferred in COPD or severe asthma

  • Less effective for controlling HR during exercise, but might lead to increased exercise capacity

  • Constipation is a common side effect for verapamil

  • Avoid in patients after MI or HF

  • $25-$60

  • Verapamil (Isoptin SR)

  • 120 mg OD to240 mg SR BID

  • $22-$52

  • Digoxin (Toloxin)

0.0625-0.25 mg OD
  • Can be used as add-on therapy to β-blockers or CCBs if HR is not controlled

  • Use for sedentary patients or LV dysfunction

  • NOT first-line therapy

  • Less effective than β-blockers or CCBs, especially in nonsedentary patients for exercise tolerance

  • Serious toxicity or side effects are possible

  • Considerable amount of drug interactions

  • Associated with increased risk of all-cause mortality regardless of the presence or absence of HF according to AFFIRM trial follow-up analysis17

  • Use cautiously in renal dysfunction

Class III antiarrhythmics
  • Amiodarone (Cordarone)

  • Loading 800-1600 mg/d for 1-3 wk, then 600-800 mg/d for 1 mo, then 100-400 mg/d; use the lowest effective dose for maintenance

  • Efficacy at 1 y 60%-70% (most effective)

  • CTAF trial18 showed amiodarone was more efficacious at preventing AF than propafenone or sotalol were

  • Possesses both rate- and rhythm-control mechanisms

  • Can be used in patients with renal dysfunction or HF (LVEF ≤ 35%)

  • Safety: many serious side effects that require judicious monitoring (see Table 7)

  • Considerable drug interactions (especially with warfarin; must decrease warfarin dose)

  • Loading dose and extensive titrating schedule required

  • Long half-life (26-107 d)

  • $31-55

  • Dronedarone (Multaq)

  • 400 mg BID

  • Efficacy at 1 y 40%

  • Fewer side effects than amiodarone

  • Less proarrhythmia than with propafenone or sotalol

  • No loading dose required

  • Should NOT be used in patients with permanent AF (increased CV mortality)

  • Relatively new drug; limited experience with efficacy and safety

  • Not covered by provincial formularies (not recommended by CDR)19

  • $150

  • Sotalol (Sotacor)

  • Efficacy at 1 y 30%-50%

  • Possesses both rate- and rhythm-control mechanisms

  • Possesses proarrhythmic qualities

  • CI in patients with CrCl < 40 mL/min (renally eliminated)

  • Bradycardia common in elderly patients

  • Avoid in women > 65 y who are taking diuretics or who have renal impairment owing to increased risk of torsade de pointes

  • $16

Class I antiarrhythmics
  • Flecainide: (Tambocor))

  • Usual dose: 50-150 mg BID; pill-in-the-pocket dose: 200-300 mg in 1 dose

  • Efficacy at 1 y 30%-50%)

  • Can be used for the pill-in-the-pocket strategy in patients without structural heart disease

  • Should be coupled with an AV nodal blocking agent (β-blocker or CCB) owing to concealed conduction and risk of ventricular tachycardia

  • CI in structural heart disease

  • Can have serious cardiac side effects (cardiac arrest, arrhythmia, AV node block)

  • $60-$85

  • Propafenone (Rythmol)

  • Usual dose: 150 mg)OD-TID; pill-in-the-pocket dose: 450-600 mg in 1 dose

  • Pill-in-the-pocket strategy: first dose is usually given and observed by a cardiologist

  • $21-$45

  • AF–atrial fibrillation, AV–atrioventricular, BID–twice daily, CAD–coronary artery disease, CCB–calcium channel blocker, CD–controlled delivery, CDR–Common Drug Review, CI–contraindicated, COPD–chronic obstructive pulmonary disease, CrCl–creatinine clearance, CV–cardiovascular, HF–heart failure, HR–heart rate, LV–left ventricular, LVEF–left ventricular ejection fraction, MI–myocardial infarction, OD–once daily, SR–sustained release, TID–3 times daily, XC–extended release. Data from Gillis et al1 and Jin and Kosar4