 Congenital or acquired QT-prolongation  Cardiomyopathy, in particular when heart failure is present  Sinus bradycardia  Existing symptomatic arrhythmias  Concomitant medication that is known to prolong QT interval Electrolyte disturbances such as hypokalaemia, hypomagnesaemia and hypocalcaemia should be monitored and corrected, if necessary, prior to initiation and during voriconazole therapy (see section 4.2).