Cardiac events don’t usually work like that. You could, for example, get permanent damage if your heart attack isn’t treated within 30 minutes (as a guideline, the circumstances vary heavily). Even an aneurism doesn’t often act quicker than 20 minutes. But ya, sub 10 minute response times only happen in a hospital, sub 1 minute response times in intensive care, etc…

Still, you feel like you are having a heart attack, call 911 (in the US) right away. The main time killer is probably just you recognizing that you need help (vs the time it takes to get help once called).

The average response time is considerably shorter than 10 minutes in many metro areas. In Los Angeles the average is 6 minutes and 14 seconds, with 98.8% of responses in under 15 minutes.