Dear Doctors: I'm a 97-year-old woman. Sometimes my blood pressure drops, and I faint. It lasts just a few seconds, because as soon as I'm prone, I wake up. I don't have any cardiac issues, and there's no pain. It's just a sudden funny feeling, then I'm out. What might be causing this?
Dear Reader: Each time the heart beats, it sends a surge of freshly oxygenated blood into the closed loop of the c…