Are Doctors Recommending Too Many Tests?

March 11, 2010— -- Many who opt for angiograms, tests designed to detect the presence of heart disease, may be receiving the test unnecessarily, according to researchers.

Nearly two-thirds of patients without confirmed heart disease who received angiograms turned out to not have heart disease, Dr. Manesh Patel of Duke University and his colleagues reported online in the New England Journal of Medicine. Specifically, only about 38 percent of these patients who underwent the elective screening procedure had potentially dangerous blockages in their coronary arteries.

Patel said the recent findings relating to angiograms should cause doctors to "carefully re-evaluate our process for determining" which patients with no history of prior heart disease should be screened using the test.

"It is still a very important place for patients with acute [heart attack], unstable symptoms, and certainly for patients for whom we're concerned about artery blockages," Patel said. But he also said that doctors must rely on other less invasive, less expensive tests as well to determine whether they need this screening.

Such an approach is supported by current guidelines. However, the methods for determining how invasive tests are ordered "are far from perfect," said Dr. Cam Patterson of the University of North Carolina at Chapel Hill, who was not involved in the study.

Researchers looked at 398,978 patients seen at 663 hospitals between January 2004 and April 2008 and found that patients without diagnosed heart disease account for roughly 20 percent of the patients who get angiograms. The vast majority are seen for other conditions that included heart attack and heart failure.

But Patel said that even within the group with no heart disease diagnosis, the fact that only 38 percent had a blockage "was surprising to us."

Angiograms are not the only tests that may be overused. Magnetic Resonance Imaging, or MRIs, CT scans, colonoscopies, and even PSA tests used to detect prostate cancer are all effective tools for the right patients. But according to many experts at times, all of these tests are overused.