Is There An Explanation For Sudden Dizziness And Chest Pain?

Hello, Yesterday I had a stress/echo which I laid on my back and pedaled a bike while the team performed an echo cardiogram. The cardiologist told me my heart was contracting or squeezing while am exhorting myself. Recently I have had chest pain with dizziness along with pain in the left areI have had angio grams, pet scans, stress tests, etc. I was told the treatment is with beta blackers, but I was not told how serious this condition is. I will say the cardiologist recieved this information during my office visit and she seemed surprised. What are the concerns for this condition.