The coronary CT angiography, a noninvasive diagnostic test for coronary artery disease, recently emerged as an alternative to the stress test – and Stanford’s Mark Hlatky, MD, recently told me he considers it a “potential game-changer with respect to how we evaluate patients with suspected heart disease.” Little has been known about the health-care use and spending among patients who undergo the test, though, and Hlatky and two colleagues recently conducted an observational study of Medicare beneficiaries to learn more.
The researchers studied 282,830 patients and examined outcomes in the six months after these patients were tested for heart disease. As I detail in a release:
After running their analysis, they found that those patients who received coronary CT angiography were about twice as likely to have a subsequent invasive cardiac procedure as patients who underwent a stress test. They also found that patients who received the CT angiography were nearly twice as likely to have a subsequent cardiac catheterization as patients who had the myocardial perfusion scintigraphy [a noninvasive imaging test], and roughly 2.5 times as likely to undergo coronary revascularization.
…The high-tech, sensitive nature of the test means that problems were being detected that led to further testing and more-invasive treatments, such as coronary revascularization.
Hlatky and his colleagues, whose work appears in the Journal of the American Medical Association, also found that heart-related health-care spending was nearly 40 percent higher among patients who received coronary CT angiography compared with myocardial perfusion scintigraphy, and nearly twice as high compared with patients who underwent stress echocardiography or exercise ECG. The next important step, Hlatky said, is to look at clinical outcome and determine whether the testing was “worth it:”
We don’t know if those extra procedures will ultimately save lives and lead to better quality of life. Our study suggests that we need more definitive clinical trials to show whether patients are better off as a result of having CT angiography instead of a stress test.
Hlatky noted that the National Institutes of Health recently launched a randomized multicenter trial to test how the choice of initial diagnostic test (coronary CT angiography or stress testing) affects patient outcomes. Stanford is one of the trial sites.
Image is a coronary CT angiogram reformatted into a 3D display