It is news likely to bring an ironic smile to the lips of many a scorned spouse - adultery is bad for the heart.
Studies show men who cheat on their wives risk not only their marriage but also their cardiac health. Liaisons away from home and with younger women are particularly dangerous.
The warnings come from Italian researchers who reviewed previous studies on the causes of infidelity and its effects. These showed "sudden coital death" was much more common when a man was meeting his mistress than when he was with his wife.
The researchers can't be sure why, but put forward a variety of reasons, including a guilty conscience. The review's authors, from the University of Florence, began by scouring medical literature for research papers including the words "unfaithfulness", "extramarital affairs", "infidelity" and "men".
This provided information about the type of man who is unfaithful and the potential consequences.