When Damar Hamlin collapsed on a football field from a frightening but fascinating medical event called “commotio cordis” (disrupted heart), the name alone sent me off to read about it in Wikipedia.
I was fascinated to learn that the “window of vulnerability” is tiny, occurring during only 1–3% of the total heartbeat cycle, when the left ventricle is “repolarizing,” getting ready to go from systole to diastole, at…
