p.28 抽出テキスト

5.2 Ongoing Management: Recommendations

Recommendations for Ongoing Management of AVNRT COR LOE Recommendations

I B-R 1.  Oral verapamil or diltiazem is recommended for ongoing management in patients with AVNRT who are not candidates for, or prefer not to undergo, catheter ablation.98,99,243,244 See Online Data Supplements 9 and 10. Both diltiazem and verapamil are well-tolerated and effective pharmacological alternatives to ablation for the ongoing treatment of patients with AVNRT.98,243 When therapy with these agents is initiated, attention should be directed toward avoiding the potential for bradyarrhythmias and hypotension. Diltiazem and verapamil should also be avoided in patients with systolic heart failure.

I B-NR 2.  Catheter ablation of the slow pathway is recommended in patients with AVNRT.36,100–106,245–249

See Online Data Supplements 9 and 10. Catheter ablation of AVNRT is regarded as first-line therapy for treatment of symptomatic AVNRT. It is potentially curative, and chronic pharmacological therapy is usually not needed after the procedure. Slow-pathway ablation (also called modification) is the preferred target during ablation of AVNRT. Large registry studies report the success rates of slow-pathway ablation to be >95%, with a <1% risk of AV block (Table 8).36,100–102,246–248 Cryoablation of AVNRT is an alternative to radiofrequency ablation. Recent systematic reviews and trials randomizing patients to radiofrequency ablation versus cryoablation suggest an equivalent acute success rate, with a lower rate of AV block but a higher rate of recurrence during long-term follow-up.156

I B-R 3.  Oral beta blockers are recommended for ongoing management in patients with AVNRT who are not candidates for, or prefer not to undergo, catheter ablation.99

See Online Data Supplement 9. Evidence for oral beta blockers is limited. One small study randomized patients with AVNRT and AVRT to digoxin (0.375 mg/day), propranolol (240 mg/day), or verapamil (480 mg/day), with 1 week of placebo washout between drug regimens.99 Episodes and duration of tachyarrhythmia (ascertained by diary and weekly 24-h Holter) were similar among the treatment groups, and all 3 medications were well tolerated.

IIa B-R 1.  Flecainide or propafenone is reasonable for ongoing management in patients without structural heart disease or ischemic heart disease who have AVNRT and are not candidates for, or prefer not to undergo, catheter ablation and in whom beta blockers, diltiazem, or verapamil are ineffective or contraindicated.45,46,107–112,114,241,242,250,251

See Online Data Supplements 9 and 10. In 1 RCT, the probability of 12 months of effective (defined as <2 attacks of arrhythmia) and safe treatment was 86% for propafenone and 93% for flecainide.109 Flecainide and propafenone have a risk of proarrhythmia in patients with structural heart disease or ischemic heart disease and are contraindicated in these patient groups. In 1 nonrandomized study, flecainide was evaluated as “pill-in-the-pocket” therapy along with diltiazem or propranolol.241,242 However, all patients were screened with EP studies, and only 5 patients were discharged on flecainide. As such, the merit of flecainide as “pill in the pocket” for outpatient therapy for AVNRT remains unclear. IIa B-NR 2.  Clinical follow-up without pharmacological therapy or ablation is reasonable for ongoing management in minimally symptomatic patients with AVNRT.244

See Online Data Supplement 10. In a prospective study of 93 adult patients with AVNRT who were followed for approximately 15 years, nearly half of minimally symptomatic patients who received no therapy (versus ablation or antiarrhythmic agents) improved over time and became asymptomatic.244 Patients with a confirmed or suspected diagnosis of AVNRT who choose not to undergo catheter ablation or take medications should be educated about when to seek medical attention and be taught how to perform vagal maneuvers. IIb B-R 1.  Oral sotalol or dofetilide may be reasonable for ongoing management in patients with AVNRT who are not candidates for, or prefer not to undergo, catheter ablation.107,114

See Online Data Supplement 9. Unlike flecainide and propafenone, sotalol and dofetilide can be used in patients with structural heart disease or coronary artery disease.113 Given the potential for significant QT prolongation and torsades de pointes, inpatient monitoring with serial ECGs is generally performed when these agents are initiated. Generally, these agents are reserved for patients who are unresponsive to, or are not candidates for, beta blockers, diltiazem, flecainide, propafenone, or verapamil. IIb B-R 2.  Oral digoxin or amiodarone may be reasonable for ongoing treatment of AVNRT in patients who are not candidates for, or prefer not to undergo, catheter ablation.99,115

See Online Data Supplements 9 and 10. One small study randomized patients with unspecified PSVT to digoxin (0.375 mg/day), propranolol (240 mg/day), or verapamil (480 mg/ day), with 1 week of placebo washout.99 Episodes and duration of PSVT (ascertained by diary and weekly 24-h Holter) were largely similar, and all 3 medications were well tolerated.99 However, the dose of digoxin used was higher than that commonly used in clinical practice today. Amiodarone is effective in suppressing AVNRT during outpatient follow-up.115 Given the potential adverse effects of digoxin and amiodarone, these agents are generally reserved as third-line therapy for patients who are unresponsive to, or are not candidates for, beta blockers, diltiazem, verapamil, flecainide, or propafenone. IIb C-LD 3.  Self-administered (“pill-in-the-pocket”) acute doses of oral beta blockers, diltiazem, or verapamil may be reasonable for ongoing management in patients with infrequent, well-tolerated episodes of AVNRT.241,242

See Online Data Supplement 9. Two studies have demonstrated success with the combination of diltiazem and propranolol as a “pill-in-the-pocket” approach to acutely terminate PSVT caused by AVNRT, but the overall safety of self-administration of these medications remains unclear because episodes of syncope were observed.241,242 If oral therapy with empiric beta blockers, diltiazem, or verapamil fails to terminate the tachyarrhythmia, patients should seek medical attention.

Downloaded from http://ahajournals.org by on October 7, 2026