I had a successful cardioversion about 2 months ago and I'm waiting for an Ablation. Pulse is a little low at about 55 bpm but I have felt ok until today. Went out walking this a.m. and had to climb a moderately steep incline. At first this caused me to be a bit out of breath but was immediately followed by feeling nauseous. I felt faint and my vision became affected and blurred. I did not pass out but had to lie flat for a about an hour. I found that my Flutter had returned and pulse was 152 bpm. After the rest and feeling much better I returned home. This evening, whilst sitting reading, I had a sudden and quiet violent spasm. No pain anywhere, just a fright. I then found that normal sinus rhythm had returned. It seemed to be a natural defibulation. Has anyone else had this occurence?