<prompt> 3-4 months baby with heart rate 250min, QRS complex less than 0.07 sec and no P wave, Diagnosis will be :SVTSinus tachycardiaPSVT with blockVT  <response>: SVTs are the most common symptomatic arrhythmias in all children including neonates.SVTs usually haveRate 200 beatsminuteNormal or narrow 0.07 sec, A wide QRS 0.07 sec favors diagnosis of ventricular tachycardia.Ventricular complexes on the surface ECG. 