Sequential appearance of ECG over time in V3 lead. A On admission to our center. Sinus tachycardia with T-wave inversion (TWI). B Admission + 6 hours. Sinus tachycardia with ST depression and prolonged QTc. C Admission + 9 hours. Junctional rhythm with ongoing ST depression/TWI. D Admission + 12 hours. Same as C. E Admission + 18 hours. Polymorphic wide complex tachycardia with QRS slurring. F Admission + 24 hours (ECMO starts minutes after this ECG). Monomorphic ventricular tachycardia with sinusoidal appearance. G Admission + 3 days, on ECMO. Nonspecific intraventricular conduction delay. H Admission + 8 days, after decannulation from ECMO circuit. Sinus tachycardia with now narrowed QRS complex and T-wave flattening. I Admission + 60 days. Sinus tachycardia.