Table 5.
Top Priority for QT Monitoring | Timeframe of Monitoring |
---|---|
1. Patients started on antiarrhythmic drug known to cause torsades de pointes (especially, disopyramide, dofetilide, ibutilide, procainamide, quinidine, sotalol) | 1. Until drug is discontinued or dosage stable and no prolonged QTc (>0.48 seconds, women; >0.47 seconds, men) and no QT-related arrhythmias (polymorphic ventricular ectopy, couplets, nonsustained VT, torsades de pointes) |
2. Patients who overdose from potentially proarrhythmic agent | 2. Until drug levels decreased and no QT-related arrhythmias |
3. Patients who have new-onset bradyarrhythmias (e.g., complete heart block, long sinus pauses) | 3. Until bradyarrhythmia resolved or definitive therapy (e.g., permanent pacemaker) |
4. Patients who have severe hypokalemia or hypomagnesemia | 4. Until electrolyte disorder corrected and no QT-related arrhythmias |
VT, ventricular tachycardia.
Adapted from Drew & Funk, 20067