Had an AVR in January 2014. This year!! cancer is back. On the other side. Underwent mastectomy in October. First mastectomy was in 2001. On chemo FEC-D. Had first chemo a week ago. Arrhythmia seems to be worse now. I was taking 12.5 mg of atenolol nightly. Feel I need more these days. Saw the cardiologist a few days ago. He said heart was good. Take more atenolol if needed. I don't like that pill - it lowers my blood pressure and makes me tired. And the chemo does a good enough job of that on it's own. Are there any other people out there who have gone through chemo after an AVR? Can you tell me how the chemo affected you? With big thanks.