A single-chamber implantable cardioverter defibrillator (ICD) was implanted as secondary prevention in a 7-year-old patient with Brugada syndrome. Ten days after the implantation, the patient came to the emergency department with chest discomfort. The electrocardiogram shown in the Figure was recorded (from precordial leads).

Figure

(0.3MB).

What is the most likely diagnosis?

• 1.

  ICD lead dislodgement.

• 2.

  Inappropriate antitachycardia therapy.

• 3.

  Early depletion of ICD battery.

• 4.

  ICD lead fracture.

Suggest a solution to this ECG Contest at http://www.revespcardiol.org/es/electroreto/69/12. The answer will be published in the next issue (January 2017). #RetoECG.