The key to interrupting heart attacks, experts say, is to get patients to a hospital and open their arteries as fast as possible.

Hospitals call it "door to balloon" time, for the tiny balloon catheters that are used to open blocked arteries.

Minnesota hospitals have some of the fastest times in the nation.

Abbott Northwestern Hospital started its "Level One" program in 2003 to try to speed up the process. Essentially, one call from a paramedic puts the entire hospital on alert, so everyone is ready and waiting when the heart-attack patient arrives -- from the security guard to the ER team to the cardiologist who inserts the catheter.

Since it started, Abbott has cut its average door-to-balloon time from 90 minutes to 44 minutes, one of the fastest turnarounds in the country, according to Barb Unger, director of cardiovascular emergencies. It also cut the death rate in half, to 5.7 percent.

Last year, Abbott and the Mayo Clinic were held up as national models in the New England Journal of Medicine for their heart-attack programs.

There's a saying among heart-attack experts: time is muscle. The faster they can restore blood flow to the heart, the less the heart will be damaged, and the better the chances of survival.

"We're doing very well at shortening the time to therapy," said Dr. Raymond Gibbons, a Mayo cardiologist and past president of the American Heart Association. But "it requires major system change to make it go as fast as possible." So far, he said, most of the country still lags behind.

But the biggest delay, says Unger, isn't in the hospital. It's patients who won't call 911.

"Over half of the heart attacks show up in ERs by car," she said. "That has got to stop."

Maura Lerner • 612-673-7384