A young athlete needs heart surgery. The surgeon discovers something conspicuous in another organ – and thus averts something bad. Recorded by Nicole Simon

When I operate, it’s usually as if I have blinders on. Then I’m maximally focused and don’t think about anything other than the next step. I am a heart surgeon. Like a pilot, I go through my checklists so that every move works. A while ago, however, I broke my routine – and in doing so, possibly saved a young man.