Have just been to the stroke clinic, and the doctor said my blood pressure was low and he said I have to stop taking the 7.5 bisoprolol and I have to just take 5mg. I have these afib episodes every 8 days and they last for 2 days, this week they lasted 3 days. Now my heart rate will be faster over 100 and I am worried about my heart beating fast every week for 2 days or more will this make my heart worse? I have my first appointment for cardiology on Nov 7th. My doctor had put me on the 7.5mg from 5mg to slow my heart rate.