CT, which produces a detailed image of the heart that reveals cholesterol(胆固醇) buildups in the coronary arteries, is widely used in the hospital around the world.

    "Testing might lead to more harm than good," said McEvoy, a doctor at Seoul National University Bundang Hospital in S. Korea.

    His team led the study, in which 2,000 healthy adults were divided into two groups. One thousand adults had CT scans and another half had standard tests, including routine checks of their blood pressure and cholesterol levels.

    After 18 months, the 215 people who had worrisome CT scans were advised to have additional tests and medical treatment, and some even advised to have surgery. But less than 10 percent in the group of standard test were reported to need medications.

    Therefore, physicians cannot easily ignore the diagnoses made by the new imaging techniques, McEvoy said, "We are left with the dilemma of what to do with the results,"According to McEvoy, doctors should focus on patients' lifestyle and traditional risk factors such as smoking and obesity.(本文由在线英语听力室整理编辑)