When Michael Rousseau takes over as CEO of St. Jude Medical in January, the hope is he’ll provide a smooth transition from longtime CEO Daniel Starks. That seems likely given that Rousseau has played a key role in the medical device maker’s remarkable C-suite stability, in an industry known for leadership turmoil. Rousseau comes from the COO’s office, where he’s been working on integrating the operations of St. Jude’s four global product divisions.