If a $100 scan of your heart and the arteries around it could show hidden heart disease, or at least the early warning for future heart disease, would you want to have it done? Even if you feel fine?

About 28,000 people in Minnesota have embraced the opportunity since 1999, when Abbott Northwestern Hospital in Minneapolis became the first in the Twin Cities to offer CT scans that spot calcium in coronary arteries.

As health providers shift to more preventive measures to control costs, hospitals such as Abbott Northwestern are focusing more of their patient marketing on their ability to use technology to see inside the body in greater detail than ever.

But the push for more scans has only heightened the debate over whether they are necessary for many of the people who get them.

At Abbott's Minneapolis Heart Institute, officials are quick to point to the early warning benefits for people considered at low to intermediate risk of heart disease, highlighting their service, called HeartScan, which measures calcium deposits in arteries around the heart. Calcium in the coronary arteries is one of the best indicators of potential heart trouble, said Dr. Thomas Knickelbine, director of preventive cardiology at Abbott Northwestern.

"We can show them this and say: 'Did I get your attention now?'" Knickelbine said of the scans, prompting people to take action to improve their health.

Still, the practice of selling scans to patients who could otherwise be healthy sparks plenty of criticism from some within the medical community. To them, it's another way for hospitals to drive up health care costs -- and boost profits -- with unneeded tests and unwarranted fears.

Gary Schwitzer, publisher of the blog Healthnewsreview.org, said the hospitals are appealing to "the worried well," as they push their scanning services.

"How do they promote this? 'You are 35 years old and you're physically inactive,' or 'You are 35 years old and have just been diagnosed with mild hypertension,'" Schwitzer said. "This gets you to come in the door and, ka-ching, you're a new health care patient."

'An inside view'

When HeartScan debuted 13 years ago, it cost nearly $500 per scan -- an amount not often covered by insurance. At the time, officials say, there was no shortage of people stepping forward, responding to advertising and getting the scans.

Now, with the cost of a scan lowered to $100 and with some insurance companies willing to pay, the number of patients can vary from several in a day to just one, said Pam Kinsley, a specialized imaging technologist who conducts the scans at Abbott Northwestern. Most of them are doctor referrals. But some just come.

"It's really advertising-driven," she said.

And that is what concerns critics.

Dr. Lisa Schwartz, a professor of community and family medicine at the Geisel School of Medicine at Dartmouth College, agrees that calcium is a "marker" for heart disease and is a risk factor. But CT scans for calcium also expose patients to radiation while the benefits of the test are uncertain, she said.

"Does knowing about [calcium] and treating you more aggressively because of it make a difference? There have been no randomized trials to show that is true," Schwartz said.

Dr. Harlan Krumholz, a professor of cardiology and investigative medicine at Yale University, said doctors are still learning how to best to use the array of imaging studies at their disposal. The question is whether the information influences what they recommend to their patients and whether they can lower their patients' risks.

The American Heart Association does not recommend "routine use of heart scans" on people who don't have any signs of heart disease. "Heart scans may not be useful for you if, based on your family history and risk factors, you fall into either a low- or high-risk category for having a heart attack."

Low-risk -- defined as a less than 10 percent risk of heart attack in the next decade -- includes people younger than 55 who have normal cholesterol and blood pressure levels and who don't smoke. High risk is defined as a 20 percent or greater chance of a heart attack in the next 10 years.

Many don't know

The truth is, Knickelbine said, people who are not considered high risk have heart attacks. And many people have no clue about their risk factors. Some haven't had their blood pressure checked for a while. For others, it's been years since they've gotten a blood test for cholesterol. Some are more sedentary than they care to admit.

"People really don't check this," he said.

For them, a scan can be a valuable wake-up call -- and a way to open the door to understanding and improving their heart health, Knickelbine said. Before getting the scan, their blood pressure and weight are checked. They are asked about exercise. If something shows on the scan, they often return for cholesterol screening or other tests.

"At this clinic, what we do isn't about scanning," Knickelbine said. "It's only a tool for all of what we do."

Studies show that a greater concentration of coronary calcium is a "strong" predictor of heart disease and helps predict trouble beyond standard risk factors.

The scan itself takes little time; the patient is only on the table of the scanner for about 40 seconds. Knickelbine said the radiation emitted by the newer CT scanner equals about what people would be exposed to in everyday life over a couple of months. Calcium appears as a spot of white on the scan image.

If the scan shows no calcium, Knickelbine said he often makes no other recommendations.

But what doctor and patient learn from a positive scan for calcium can lead to important lifestyle changes, a better diet and improved health, Knickelbine said.

Sometimes, it takes that little spot of white to convince people to act, he noted. "Whatever it takes to get people to start taking the initiative."

James Walsh • 612-673-7428