CT Images Reveal Serious Problems Outside The Heart
Trained eyes needed to spot small cancers, blood clots and aneurysms early
Nearly half of all patients who get their hearts scanned with a high-speed CT scanner may get a shocking surprise: a diagnosis of a serious problem that has nothing to do with their heart.
New research from the University of Michigan shows that 43 of 98 patients who had a CT heart scan to look for clogged arteries were also found to have significant or potentially significant signs of problems with their lungs, blood vessels or organs.
These discoveries ranged from possible lung cancer in 16 patients to potentially dangerous blood clots and aneurysms in 10 patients. The results are being presented here today at the American Roentgen Ray Society's annual meeting by cardiac imaging specialists from the U-M Cardiovascular Center.
The researchers say their data show just how important it is for trained radiologists to view heart CT scans, as is done at the U-M Health System, rather than having the scans read by heart specialists alone. They note that there has been explosive growth in the number of patients having CT scans to diagnose or monitor heart disease in recent years.
"Many of these patients are having their scans at cardiology centers that may or may not employ a physician who specializes in radiology and has been trained to spot problems of any kind on medical images," says lead author Smita Patel, M.B.B.S., an assistant professor of radiology at the U-M Medical School and member of the U-M thoracic (chest) radiology team. "Our research suggests that may leave potentially serious problems undiagnosed. The trained eyes of radiologists are needed."
The rapid rise in CT heart scans, known as CT coronary angiography or CTCA, has given more patients and their doctors a detailed view of the coronary arteries that feed the heart muscle without an invasive procedure.
"The new cardiac CT that we can perform today can assess the arteries supplying the heart for blockages without requiring the patient to undergo catheterization, which involves a tube inserted through the groin into the heart to assess these arteries," says Patel. "When the arteries are normal, the patient often does not need to undergo further cardiac testing."
But the scans also reveal the finest details of structures near the heart including the lungs, aorta, liver, pancreas and the structures and spaces that surround them. And that level of detail is only increasing as CT scanners become more powerful.
Patel and her colleagues looked at images taken with U-M's 16-slice multidetector CT scanners. But in the last year, U-M and other major centers have acquired even more powerful 64-slice CT scanners that can image the entire chest in just a few seconds, allowing even the fast-moving heart muscle and arteries to be seen clearly.
The simultaneous rapid increases in the precision and utilization of CTCA, says Patel's co-author Ella Kazerooni, M.D., makes it important to study the rate at which non-heart problems are found.