[CK] Tikosyn loading

Conversion of Atrial Fibrillation/Flutter to Normal Sinus Rhythm

QTc must be <440 msec (or <500 msec with ventricular conduction abnormalities) before initiating first dose; contraindicated if >440 msec (or >500 msec with ventricular conduction abnormalities)

Initial dose

·         CrCl >60 mL/min: 500 mcg PO q12hr

·         CrCl 40-60 mL/min: 250 mcg PO q12hr

·         CrCl 20-40 mL/min: 125 mcg PO q12hr

·         CrCl <20 mL/min: Contraindicated

Sinus Rhythm Maintenance After Conversion

·         Post initial dose adjustment based on QTc (2-3 hours after initial dose)

·         If QTc increases <15% of baseline, continue current dose

·         If QTc increases >15% or >500 msec (550 msec with ventricular conduction abnormalities) decrease dose as follows:

·         If initial dose 500 mcg q12hr, decrease to 250 mcg q12hr

·         If initial dose 250 mcg q12hr, decrease to 125 mcg q12hr

·         If initial dose 125 mcg q12hr, decrease to 125 mcg qDay

Monitoring

Must be hospitalized to initiate

Measure QTc 2-3 hours after first 5 doses during inpatient stay

Discontinue dofetilide if at any time after second dose, QTC >500 msec (550 msec with ventricular conduction abnormalities)