Arrhythmia Treatment Guidelines

Efficacy of Treatment

A probability of effective treatment of 93% (defined as <2 attacks of arrhythmia in 12 months) for AVNRT can be achieved, according to the American Heart Association 1
Flecainide can be used as "pill-in-the-pocket" therapy for selected patients with arrhythmia, though evidence is limited, as stated by the American College of Cardiology 1
Flecainide is effective in preventing recurrent episodes of SVT, with an efficacy of 85-90% in patients without structural heart disease, and is recommended at an initial dose of 50 mg twice daily, which can be increased in increments of 50 mg twice daily every four days to a maximum of 300 mg/day 2, 1, 3
The addition of a beta-blocker to flecainide increases efficacy to >90% of patients achieving abolition of symptomatic tachycardia 3

Minimally symptomatic patients with AVNRT may be considered for clinical follow-up without pharmacological therapy, as recommended by the American Heart Association 1
Flecainide, a Class IC antiarrhythmic drug, is superior to verapamil, a non-dihydropyridine calcium channel blocker, for preventing recurrences of supraventricular tachycardia (SVT), with higher rates of complete symptom suppression (30% vs 13%) 2, 1
Flecainide is preferred for patients with frequent, symptomatic SVT episodes, no structural heart disease, and a need for higher complete suppression rate, as recommended by the American Heart Association 1
Verapamil is preferred for patients with structural heart disease, need for rate control, or hypertension, according to the American College of Cardiology 4

Flecainide is contraindicated in patients with structural heart disease, recent myocardial infarction, or significant ventricular dysfunction, as stated by the European Society of Cardiology and American College of Cardiology 1, 4
Verapamil should be used cautiously in patients with structural heart disease, and is primarily used for rate control rather than rhythm conversion, according to the American College of Cardiology 4
Patients with structural heart disease should avoid flecainide and use verapamil or alternative agents, such as sotalol or dofetilide, as stated by the European Society of Cardiology and American College of Cardiology 1, 4, 3

Vagal maneuvers are recommended as first-line treatment for acute management of SVT, with a success rate of terminating SVT in approximately 50% of patients 1
The American Heart Association recommends synchronized cardioversion as the immediate treatment for SVT with hemodynamic instability (Class I recommendation), and the American College of Cardiology recommends assessing hemodynamic stability first, and if unstable, proceeding with immediate synchronized cardioversion 1
A recommended treatment algorithm for acute management of SVT includes vagal maneuvers as first-line, IV adenosine as second-line, and IV beta-blockers or calcium channel blockers as third-line for stable SVT 1

Beta blockers, diltiazem, or verapamil are first-line medications for ongoing management in patients without pre-excitation, with a recommended initial dose and titration based on patient response 1
Flecainide is recommended as a second-line agent for ongoing management of SVT in patients without structural heart disease who are not candidates for catheter ablation or in whom first-line agents are ineffective or contraindicated 1
Sotalol has been shown to be effective in preventing symptomatic recurrences, with 13 of 16 patients being free of symptomatic recurrences during a median follow-up of 36 months, and is recommended as an alternative to flecainide in patients with structural heart disease 3, 1

The American Heart Association recommends catheter ablation as the first choice for long-term prevention of SVT, with a 93-95% success rate, and flecainide as a second-line option if ablation is not feasible 1