The University of Minnesota this week is marking the 25th anniversary of its first human heart transplant. A number of people who have received new hearts at the hands of university surgeons will gather to mark the anniversary,including the university's longest-surviving heart transplant recipient. The first human heart transplant was done in South Africa in 1967. Since the U of M began doing the procedure 11 years after that, university surgeons have performed almost 500 heart transplants, including 28 so far this year. The recipients have ranged from 6 months to 70 years old. Dr. Leslie Miller is the director of the University's heart transplant program. He joins us now.