Ray Grefe woke up on June 17, 2005, the day before Father’s Day and six days before his 55th birthday, with a sharp pain in his shoulder blades. It was 4 in the morning. His wife, Carol Lei, was asleep.

So he took a double dose of painkillers — aspirin plus Tylenol — and went back to bed. When he woke up again at 7:30 and told Ms. Lei that he was still in pain, she suggested that he skip the family outing to the zoo that morning and go to the nearby St. Mary’s Hospital to have his shoulder checked out. They figured he’d pulled a muscle the previous day, probably while rolling around with his 4- and 5-year-old daughters or hitting golf balls at a driving range.

The family was in the car, just a few blocks from their San Francisco house, when the pain suddenly shot into Mr. Grefe’s arm and he began sweating. In as relaxed a voice as he could muster, hoping not to alarm his daughters, Mr. Grefe said to his wife, “I’m having a heart attack.”

St. Mary’s, their usual hospital, wasn’t the closest one to their home, so Ms. Lei instead drove to the University of California, San Francisco, Medical Center, just minutes away. Time would turn out to be crucial: the primary artery feeding Mr. Grefe’s heart was entirely blocked.

The hospital where he ended up, known as U.C.S.F., is one of the top medical institutions in the world. Three of its researchers have won the Nobel Prize in the last two decades. It’s the sort of place that should be able to handle heart attacks.

For years, the doctors who worked there thought they were doing exactly that. They hadn’t actually looked at the data, but they assumed they were doing a good job of moving patients quickly into a catheterization lab and opening up their arteries to get blood flowing again. The attitude, recalled Dr. Robert M. Wachter, chief of the medical service, was: “We’re U.C.S.F.; we’re smart; we do fine.”

But in 2002, when they realized that hospital regulators would soon be releasing the data to the public, they started paying attention to it. Shockingly, heart attack patients spent almost three hours on average at U.C.S.F. before their arteries were unblocked. Some had their electrocardiogram languish on a clipboard in the emergency room while doctors dealt with other patients. Others got a diagnosis quickly but had to wait until a cardiologist and the medical technicians arrived at the hospital.

To be fair, U.C.S.F. was faster than most hospitals, but its delays were still almost certainly killing some people and leaving others disabled. Patients have the best chance of recovery if their arteries are opened within two hours, research has shown. At one meeting to discuss the hospital’s performance, Brigid Ide, a nurse and U.C.S.F. executive, said to her colleagues, “This is O.K., but if this were your father, is this the time you would want?”

Prodded by the threat of public embarrassment, doctors and nurses got to work. Dr. Thomas A. Ports, a top cardiologist, began carrying two pagers, one for general matters and another that would go off only when someone had come to the hospital with a heart attack. The emergency room made a new rule that a staff member had to get a doctor’s signature on an electrocardiogram as soon as it came out. A bright red toolbox, labeled as the heart attack box, now sits on a shelf in the E.R., filled with basics like aspirin and nitroglycerine.

By 2003, the hospital had cut its response time to about 90 minutes, which was where it was when Mr. Grefe arrived in June 2005. He was whisked from the E.R. to the operating table. There, doctors opened the artery that had been completely blocked.

The kind of heart attack he had is known as the “widow maker,” yet on Thursday of the following week, five days later, he was making phone calls for his job as an account executive at Navteq, the company that sells map data on Mapquest, Google and other Web sites. “Obviously, I was extremely lucky,” he told me last week. “The experience certainly could have been a lot worse. Let’s put it that way.”

In the current, long-overdue debate about health care, the focus is almost entirely on health insurance. And there is no question that the country would be better off if everyone were covered. But the gaps in insurance aren’t the only problem with the medical system. They are not even the biggest problem.

Just think about what was happening at U.C.S.F. Most of the heart attack patients there had health insurance, but they were still getting substandard care. The same is true today about diabetes and hypertension. Only about a third of people with those conditions receive the care that’s needed to manage their case.

The most encouraging thing about the U.C.S.F. story is that it points out a way to improve health care that avoids many of the thorniest political debates: regulators should force hospitals to report more information. In 2005-6, about 67 percent of patients across the country had their arteries unblocked within two hours, up from 62 percent a couple of years earlier, according to Medicare, which posts the numbers on the Web.

Releasing data does not solve every problem, of course. Since its initial burst of progress, U.C.S.F. hasn’t gotten any faster at opening arteries; in 2005-6, 77 percent of heart attack patients there received treatment in less than two hours. With many other kinds of care, it’s difficult to come up with the right performance measures and to make adjustments for the mix of incoming patients.

But it’s not as difficult as doctors and hospital administrators sometimes suggest. (Not all of them are keen on accountability.) In fact, since the early 1990s, New York State has released death rates for heart surgery — and those rates have fallen far faster than the national average during that time. Pennsylvania now requires its hospitals to disclose how many of their patients acquire hospital infections.

There is far, far more that could be reported: survival rates for cancer, strokes, cystic fibrosis and a host of other conditions; measures of neonatal intensive care; complication rates from Caesareans. “You can find out a lot more about buying a washing machine than buying health care,” said Senator Ron Wyden, an Oregon Democrat who is pushing health care reform.

The funny thing is that while patients remain largely ignorant of the information that is already available, it has still inspired hospitals to make big changes. But maybe that shouldn’t be too surprising. Doctors and nurses, like most everyone else, apparently care what their peers think of them. As Dr. Wachter says, “I think people underestimate the role of pride.”