When my dad was in his 80's, he had episodes similar to the one you just described, only scarier. My mom started to sit on the sofa and he said "Don't sit there! You'll sit on that little girl!" Mom called me terrified that it might be Alzheimers. As it turns out, his medication was causing him to behave in that manner. He didn't have high BP or diabetes but he did have heart problems towards the end, although he never did have a heart attack. Perhaps your dr. could check his meds and see if that could be the culprit. Once they adjusted my dad's meds, he never had another episode like that.