Two instance I can recall: at the Jersey City assembly hall, an elderery brother succumbed to a heart attact while the Circuit Overseer was on the platform. It happened at the rear of the round floor, or back of what was the ochestra section, of the building. The commotion caused the CO to angrily order an edit to the noise, and continued on his merry way with his useless lecture.
Another: On a PBS program a documentary which highlighted the work of paramedics, several of the first responders related an incident at a Kingdom Hall where they were called to rescue another victim of a heart attack. They said that as they were administering first aid, several JWs sought to push literature on them; it caused them to remark on the JWs strange set of priorities.