Forceps! Scalpel! Robot!

We're going to take real good care of you, you know that?" says Dr. Robert Michler, as he fixes his dark blue eyes on the 79-year-old patient to whom he's about to give a heart bypass. "I know that," answers Paul Oaks with a placid smile, as he lies on a gurney in a thin gown and floppy hospital cap.

Oaks has good reason to trust his surgeon. With more than 3,000 open-heart operations and some 400 transplants under his belt, Michler, chief of cardiothoracic surgery at Ohio State University Medical Center in Columbus, is no novice. Then again, today's procedure...