Midnight punctual tachycardia

Upon admission, we treated him consecutively with amiodarone, procainamide, propranolol, lidocaine, and eventually sedation and intubation [1].During the day, the patient remained free of arrhythmias.However, at night we observed repetitive nocturnal ventricular tachycardias beginning precisely at midnight and recurring at regular intervals of 30 min, for a total of six episodes, as illustrated in Fig. 1.The onset of this VT is shown in Fig. 2.What could be the aetiology of this recurring nocturnal arrhythmia? AnswerYou will find the answer elsewhere in this issue.Midnight punctual tachycardia