TIME IS MUSCLE: Acting quickly after heart attack symptoms start can be a heart saver. “The longer the time between when heart attack symptoms start and a patient has an artery-clearing percutaneous coronary intervention (PCI), the more damage to the heart muscle.”

Hospitals have worked to cut “door to balloon time” — the lag between when you show up and when they’ve got you under a cath — but they can’t do anything about how fast you get to the door. If in doubt, go: If you’re wrong you’ve wasted a few hours. If it’s a heart attack, delaying can kill you, or leave you a heart cripple unnecessarily.