My Mother in law has been on Digoxin for about three years for A fib. At her last Cardiologost appt. they told her to stop Digoxin and start Atenolol . She stopped the Digoxin but did not start the Antenenol right away. Her breathing was difficult almost right away and so she was told to restart the Digoxin. She then added the Anteneol (sp) Now she has decided to stop both as her breathing is very difficult in the mornings upon rising. I think she should go back to the Digoxin ASAP but not sure about the Antenenol as she was having small black out spells which she described as falling asleep and falling from her chair. This happened though before the Antenenol. What do you think