Hi, I am a 53 year old African American woman, 5 4 185lbs, run 2-4 times a week, strength train 1-2 times a week, take 1/2 10mg Lysinopril each day for blood pressure that has been slightly elevated for 4 years. Eat right, most of the time and lately I have had very rapid heart beat. For no apparent reason....... Just recently lost 10 pounds using Dr. Ian Smith Super Shred book. I had this happen last year, EKG, stress test came back normal......should I be concerned?