Accordion QRS dance

An 81-year-old woman was admitted to the emergency department for collapse. She has no known medical history. The clinical examination shows a heart rate oscillating between 160 and 180, a BP at 78/55 mm Hg, a GCS at 14 (E : 4, V : 4, M : 6), an oxygen saturation at 89%. She has cyanosis going from the feet to the knees. An ECG was done (see figure 1). Figure 1 ECG at the emergency department. What is your diagnosis ? 1. Ventricular tachycardia. 2. Ventricular fibrillation. 3. Wolff-Parkinson-White. …