Could be many things. High BP doesn't mean it's a heart problem. It could simply be a trapped nerve in the shoulder/neck or arm, you'll be surprised how much like Cardiac pain they can feel. My family has heart problems and I (at the moment) have high BP and high cholesterol
i began to get arm/chest pain
only to discover it was a combination of stress (loss of my Mum to Heart) and a trapped nerve in my back. High BP needs to be treated so if they aren't taking meds they should be. Heart pain is usually accompanied with tightness of the chest, shortness of breath
, back pain
, arm pain shooting into the jaw, vomiting
etc. Always best to get it checked though to be safe.