Chest pains

I have had polycythemia since 1985 and take 6 hydrea, 1 gleevax and 6 agraline a day to control the counts. I have been getting chest pains now for a few months that mimic a heart attack that last anywhere from just a few seconds to up to f15 mins. I have had a stress test done and it is normal. Does anyone else get chest pains or does anyone know what can cause them. Lil