PO-01-136 SAFETY AND EFFICACY OF 375 MCG DOSE OF DOFETILIDE IN PATIENTS WITH ATRIAL FIBRILLATION

Abstract

Dofetilide is a class 3 antiarrhythmic drug approved in the treatment of persistent Atrial Fibrillation (AF). Previous randomized and controlled studies have assessed the safety of this drug at dosages of 125 mcg, 250 mcg and 500 mcg. However, efficacy has been shown to be dose dependent. We evaluated the safety and efficacy of 375mcg bid dose in the treatment of AF. We have collected data on all patients admitted for dofetilide initiation at 2 institutions. We reviewed the medical records to collect information on baseline characteristics at the time of initiation. Dosage, cardioversion parameters and discharge modalities were all recorded. Follow-up events were recorded including recurrence of AF and mortality. Follow-up ended when dofetilide was discontinued. 100 pts were successfully discharged on a 375mcg bid dosage out of 700 pts admitted for dofetilide initiation. Mean GFR by Cockroft was 106,63 (43.6-154.9), mean Baseline QT corrected by Fridericia (QTcF) was 426.77 (368-525); mean Discharge QTcF was 472.43 (427-519). 70% of the pts had persistent AF and 50% of the pts who got 375 mcg dose were in sinus rhythm at 1 year. No case of ventricular tachycardia was reported. The dose of 375 mcg appears to be safe and as effective as the 500mcg dose as reported in SAFFIRE-D trial (46% AF free at 1 year and 37% pharmacological cardioversion). This should be considered in dosing algorithm for inpatient dofetilide initiation.