What is the use of Sotalol (beta blocker and antiarrhythmic medication)?

From the Guidelines

Sotalol should be used with caution in patients with atrial fibrillation, as it is not effective for conversion to sinus rhythm but may be used to prevent recurrence, with a typical starting dose of 80 mg twice daily, and careful monitoring for QT interval prolongation is mandatory 1.

Key Considerations

• Sotalol is a beta-blocker with Class III antiarrhythmic properties, which can prolong the action potential duration in cardiac tissue.
• The medication requires careful dosing adjustments in patients with kidney impairment, as it is primarily eliminated through the kidneys.
• Treatment should begin in a monitored setting due to the risk of QT interval prolongation, which can lead to a dangerous arrhythmia called torsades de pointes.
• Common side effects include fatigue, dizziness, shortness of breath, and bradycardia (slow heart rate).

Important Safety Information

• Sotalol should not be abruptly discontinued, as this can worsen arrhythmias or precipitate cardiac events; instead, the dose should be gradually reduced over 1-2 weeks.
• The medication works by blocking beta-adrenergic receptors in the heart, reducing heart rate and contractility, while also blocking potassium channels, which prolongs repolarization and helps maintain normal rhythm.
• According to the 2011 ACCF/AHA/HRS focused updates incorporated into the ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation, sotalol may be initiated in outpatients with little or no heart disease, as long as the baseline uncorrected QT interval is less than 450 ms, serum electrolytes are normal, and risk factors associated with class III drug–related proarrhythmia are considered 1.

Comparison with Other Medications

• Sotalol was found to be as effective as propafenone in maintaining sinus rhythm in patients with atrial fibrillation, but less effective than amiodarone in preventing recurrence of atrial fibrillation 1.
• The "pill-in-the-pocket" approach, which involves self-administered oral loading of flecainide or propafenone, appears feasible and safe for selected patients with atrial fibrillation, but the safety of this approach without previous inpatient evaluation remains uncertain 1.

From the FDA Drug Label

Sotalol AF are indicated for the maintenance of normal sinus rhythm [delay in time to recurrence of atrial fibrillation/atrial flutter (AFIB/AFL)] in patients with symptomatic AFIB/AFL who are currently in sinus rhythm. Sotalol is also indicated for the treatment of documented life-threatening ventricular arrhythmias and is marketed under the brand name Betapace® (sotalol hydrochloride).

Indications for Sotalol:

• Maintenance of normal sinus rhythm in patients with symptomatic AFIB/AFL
• Treatment of documented life-threatening ventricular arrhythmias 2 Key Points:
• Sotalol AF should be reserved for patients in whom AFIB/AFL is highly symptomatic
• Patients with paroxysmal AFIB whose AFIB/AFL is easily reversed should usually not be given Sotalol AF 2
• Sotalol hydrochloride tablets must not be substituted for sotalol hydrochloride tablets (AF) because of significant differences in labeling 2

From the Research

Sotalol Overview

• Sotalol is a nonselective beta-adrenoceptor antagonist with class III antiarrhythmic properties, which prolongs cardiac repolarisation independently of its antiadrenergic action 3, 4.
• It has a unique pharmacologic profile, with a broader antiarrhythmic profile than conventional beta-blockers 4.
• Sotalol is effective in controlling paroxysmal supraventricular tachycardias, ventricular response to atrial fibrillation/flutter, and preventing initiation of supraventricular tachyarrhythmias following coronary artery bypass surgery 4.

Therapeutic Uses

• Sotalol is used to treat atrial fibrillation (AF), ventricular tachycardia, premature ventricular contractions, and supraventricular tachycardia 5.
• It is effective in maintaining sinus rhythm after cardioversion of atrial fibrillation/flutter and in preventing recurrent ventricular tachycardia and ventricular fibrillation 3, 4.
• Sotalol has shown superior efficacy for prevention of recurrent ventricular tachycardia and ventricular fibrillation compared to class I antiarrhythmic drugs 3.

Administration and Dosage

• The initial dose of sotalol is 80 mg twice daily, with gradual titration to 240 to 360 mg/day as needed 3.
• The daily dose must be reduced in renal failure 3.
• Sotalol can be administered intravenously, with a recommended dose of 75-150mg over 5 hours 6.
• Outpatient initiation of sotalol is possible in select patients with cardiac implantable electronic devices (CIEDs) for continuous remote monitoring and surveillance capabilities 7.

Safety and Efficacy

• Sotalol has a relatively low proarrhythmic risk and is haemodynamically well tolerated 4.
• The major side effects of sotalol are related to beta-blockade and the risk of torsades de pointes, which is acceptably small if appropriate precautions are taken 3, 4.
• Sotalol has shown efficacy equivalent to propafenone and quinidine in preventing atrial fibrillation recurrence, but is better tolerated than quinidine 3.
• No adverse effects relating to QTc prolongation and torsades de pointes or mortality were observed in a study of outpatient initiation of sotalol in patients with CIEDs 7.