In the prevailing more-is-better culture, patients often jump at or at least surrender to the latest and greatest medical test. New imaging technology is gaining crispness with each passing year, and advances in the past several years has enabled doctors to peer inside the body to detect tiny tumors or the beginning of a blocked artery—all without slicing the skin. As cancer scans gain closer scrutiny for their efficacy, a new study calls into question the benefits of a high-tech test for heart disease.

When compared to previous, exercise-based tests, this newer screening method turns out to be leading to many more surgeries—and subsequently higher medical costs—without the data to show that it's actually helping people live longer or stay healthier, according to an analysis published online Tuesday in JAMA, The Journal of the American Medical Association.

The new technology, called coronary computed tomography angiography, uses CT scans to visualize patients' coronary arteries and has become increasingly popular in the past five years. Previous methods for testing for heart disease involve an exercise-based stress test using ECG (electrocardiography), cardiac perfusion scans or other readings. The sensitivity of the newer approach, however, might also prove to be its weakness.

"If you pull a 75-year-old off the street and give him the test, it's unlikely that the coronary arteries will be completely normal," study co-author Mark Hlatky, a professor of medicine and health research and policy at Stanford University School of Medicine, said in a prepared statement. But whether a slightly abnormal reading indicates a level of sickness that should necessitate surgery, such as catheterization or revascularization, is one of the big questions at hand for this and many other diagnostic advances.

In a study of more than 282,800 Medicare beneficiaries who received non-invasive testing for heart disease between 2006 and 2008, only about 3 percent received the newer CT-based screening. Those who did receive this form of screening, however, were more than twice as likely to later receive coronary catheterization and two and a half times more likely to undergo cardiac revascularization when compared with those who were tested with profusion scans. These CT patients were similarly more likely to undergo these procedures as those who had gotten ECG-based tests.

"We don't know if those extra procedures will ultimately save lives or lead to better quality of life," Hlatky said. They certainly meant higher medical costs, racking up an average of almost $14,943 per patient in the 180 days following the CT test, which is considerably more than the $10,626 to $7,991 associated with the profusion and ECG tests.

The findings don't suggest scrapping the higher-tech test, but the take-away message is that this, and many other new tests should be evaluated to see if they are really improving life for patients in the long run.