Management of Cardiac Risk during Methadone Treatment: Focus on the QT Interval

In recent years, methadone, along with various other drugs, has been implicated in the lengthening of the QT interval of the electrocardiogram (ECG) and in the onset of potentially fatal arrhythmias. The risk of prolonged QT in methadone-maintained subjects is estimated at between 2-4%, while the risks of torsades de pointes or sudden death are extremely low. Despite the diversities reported, the guidelines available to date indicate the need to implement preventive measures based on ECG screening. The impact of these recommendations is, however, limited by the lack of a comparative risk/benefit assessment of specific procedures.