Oldbikah,
I take 25 mg Atenolol. I just had problems last week, after stepping down from 50mg. I got chest pains going up a grassy hill and had to get off and walk. My heart rate sped up to over 160.

I talked to my dr and he's not concerned, but since then I've felt "heaviness" in my chest, but on either side. And I had a very low hr for me for the last couple of day in the 60's. Why do you take it? The beta blockers are helping to "protect" your heart. Are you taking anything else it might be reacting with? Are you taking it at the same time every day? Depending on dosage, maybe it should be split during the day to keep the levels consistant (something dr. don't seem to tell people). And when you decrease doses, it needs to be stepped down not stopped. If you want to email me at all send me a message.