NEW DELHI — Taken out of context, it looks like Naresh Trehan is playing a video game. He stares intently into a console at a three-dimensional image, his feet pressing on pedals, his hands maneuvering levers.

But in this case, context is everything. On a television screen several feet from Dr. Trehan, a heart, embedded in gelatinous tissue and blood, throbs insistently. Several feet farther still, lies the body that is home to the heart, on which Dr. Trehan is, at this moment, operating.

He moves a lever, and on the screen, a robot's claw lifts the internal mammary artery, soon to be joined with the coronary artery in a single bypass. Dr. Trehan is providing the brainpower by remote control. Two robotic arms with tiny hands, inserted through two small incisions in the torso, and a tiny camera inserted through a third, are doing the work.

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