The researchers, led by Dr. Robert Case of Manhattan’s St. Luke’s-Roosevelt Hospital, don’t purport to explain their finding. Human contact may subtly affect heart function, they suggest–or it may simply improve one’s chances of getting quick medical attention in an emergency. But whatever the mechanism, one needn’t be married to tap it. Patients who had lost their spouses were at no greater risk than anyone else, as long as they didn’t live alone. From the heart’s perspective, it seems, a friend is as good as a lover.