This isn't a typical stroke symptom. Some unusual stroke symptoms affect the spinal cord instead of the brain, and that might cause this type of sensation. But more likely it's related to another medical issue. It could be as simple as an acid reflux problem, which might be relieved by propping him up on more pillows at night. But it could also be a type of angina, which requires evaluation. He really needs to consult his doctor to make sure it's not a symptom of something serious, like heart disease.