A case report from 2010 describing a 29-year-old man whose atrial fibrillation converted to a normal rhythm during a digital rectal exam is circulating again after the physician who published it retold the story on Instagram. It is a good story. It is also fifteen years old; it involves exactly one patient, and at least one cardiologist has publicly questioned the part of the account that makes it memorable.
That combination is worth unpacking, because the case is real, the mechanism is plausible, and the conclusion most readers will draw from a viral clip is wrong.
