I am 75. I take 75 mg of atenolol and 40 mg of benazepril hcl every day. I had an echo stress test (speed increases every two minutes) and at 6 minutes my blood pressure starting falling so the test was stopped and the doctor said sometimes with blood pressure medicine that happens. He said my heart was fine. I had a by-pass 12 years ago. So do I have to worry?