My father is 85 years old and has severe arthristis in his shoulders. He has had a lot of pain for years and it has gotten worse where he went back to the doctor, and they changed his pain RX. But a couple of times it has gotten severe and we cannot tell if it is his shoulder pain or heart, because he has also had previous heart problems. We went in August to the ER because the pain was so bad plus he broke out in a sweat which concerns us. He stayed overnight then sent him home, things checked out OK. Same thing happened Sunday, but he is now still in the hospital trying to decide if it his shoulders or maybe his heart. He says the pain feels like the shoulders but is intense and a nitro usually helps. Can nitro pills take pain away in his shoulders if it is not heart realted?