This is what saves 600,000 people every year during a heart attack. Your heart is running out of time. Every second an artery stays blocked, heart muscle dies — and open-heart surgery isn’t fast enough. That’s why doctors use a coronary stent. A catheter snakes through your wrist or groin to the exact site of the blockage. A balloon inflates, and a tiny metal mesh tube — smaller than your fingertip — locks the artery open permanently. Circulation restored. Heart muscle saved. Patient walking out