A 79-year-old man with a dual-chamber defibrillator for the last 6 years presents to the emergency room with a 3-hour history of palpitations. He is hemodynamically stable (blood pressure, 130/70mmHg) and has not received any shocks from the device. An electrocardiogram is recorded (Figure).

Figure

(0.78MB).

What is the diagnosis with this trace?

• 1.

  Polymorphic ventricular tachycardia

• 2.

  Atrial fibrillation with aberrant conduction

• 3.

  Monomorphic ventricular tachycardia and atrial fibrillation

• 4.

  Pre-excited atrial fibrillation (left lateral accessory pathway)

Suggest a solution to this ECG Contest http://www.revespcardiol.org/en/electroreto/70/3. The answer will be published in the next issue (April 2017). #RetoECG.