Polymorphous ventricular tachycardia in a child

Tracing
N° 6
Manufacturer Medtronic Device ILR Field Reveal DX / Reveal XT
Patient

A 14-year-old adolescent without personal or family medical history presented after 4 episodes of syncope. Except for early repolarization in the inferior ECG leads and ventricular extrasystoles originating from the left ventricular outflow tract, all investigations were negative. Following another syncopal episode, antiepileptic therapy was introduced because of electroencephalographic abnormalities and a Reveal DX was implanted because of early repolarization recently described as a putative predictor of sudden death.

Graph and trace

The device automatically recorded an event. The text described an episode detected in the FVT zone, which lasted 5 sec.

  1. normal sinus rhythm;
  2. prominent ventricular ectopy and bigeminy;
  3. polymorphous VT at a rate near 400 bpm;
  4. spontaneous termination with persistence of ventricular ectopy.
Comments

This young patient was treated with quinidine and received an ICD. This case illustrates several important points: 1) he was initially treated with an antiepileptic regimen for recurrent syncope, a common observation in cases of catecholamine-mediated VT or congenital long QT syndrome; 2) the ECG showed early repolarization, a common observation in the healthy population, seriously complicating the risk stratification of sudden cardiac death. The place of the ILR in this context is equally delicate. As in this case, it allows revisiting the diagnosis, eliminating a probably useless antiepileptic treatment, considering a cardiac cause and reorganizing the treatment. On the other hand, this episode was particularly concerning, as it evoked a clear risk of fatal outcome. The role of the ILR in the risk of sudden death stratification in patients presenting with Brugada syndrome or early repolarization remains controversial and in need of further investigation.