1152
Of particular interest in this patient is the fluctuation of the QT interval at a stable dose of methadone, suggesting that a single normal electrocardiogram (ECG) does not guarantee that the patient is not at risk of ventricular arrhythmias.
 adverse event: at 
Please tell me event type and its trigger word from given type options. Output format is "type: trigger".  Option: adverse event, potential therapeutic event 
Text: {0} 
Answer:
 adverse event: at 