The Classic Fontan has been abandoned these days due to occurrence of rapid and incessant complications. Presence of complications like, morbid obesity, obstructive apnoea, chronic atrial flutter, elevated Fontan pressures as seen in our patient, increases the risk of Anaesthesia manifold times. We report a case of 32 year old male patient with failing modified Fontan and aforementioned complications, posted for radiofrequency ablation under general Anaesthesia.