When a patient presents at a hospital with shortness of breath, chest pain and/or extreme fatigue, they will most likely undergo a stress test. But researchers at Johns Hopkins University in Baltimore have discovered that a CT scan could be a better way of detecting any blockage in a person's arteries.

“My hope is that the field of cardiology will change its approach to patients with suspected coronary heart disease – patients with chest pain,” said Dr. Armin Zadeh, lead investigator for the research and associate professor of medicine at Johns Hopkins, told HCB News.

“I believe our traditional sequence of testing (stress testing first) should be reversed for most patients. Unless the probability of coronary heart disease is low, the patient should get a CT first because of some degree of blockages, and then undergo either stress testing or cardiac catheterization,” he added.

The study showed each patient undergoing three types of tests for clogged arteries which included non-invasive CT angiograms, traditional catheter-based coronary angiographies and then an exercise stress test two months later. The scans correctly discovered blockages in nine out of 10 patients, while stress tests only found six out of 10.

The report was published online in the journal Circulation: Cardiovascular Imaging.

CT angiogram has just recently become another non-invasive test for heart patients. A handful of studies, Zadeh said, have suggested that these could be superior to any other tests. But uncertainty remains because of the small number of people actually involved in the research.

The newer CT scans give out much lower doses of radiation than the scans used in nuclear stress tests, but it all varies from hospital to hospital, Zadeh’s report said.

“Since the costs are similar (for CT scans and stress tests), physicians will not be deterred by costs to order a CT. The key issue is reimbursement by insurance carriers,” he said. “If doctors have to ask for authorization prior to ordering it, they will be less inclined to order a CT study -- which is the actual deterrent.”

Patients may simply inquire about a CT as an alternative to stress testing. Unfortunately, insurance companies may decline payments for a CT depending on the patient’s coverage.

Currently guidelines from the American Heart Association and the American College of Cardiology call for a stress tests in all patients who show signs of heart disease. Only patients with bad or borderline stress test results undergo CT angiograms.

“It likely will take years before these changes will be implemented into guidelines,” Dr. Zadeh explained. “This is the nature of our system. In the meantime, each physician has to decide for herself/himself what’s best for the patient.”

Each test has its limitations, he said, which need to be weighed against its benefits. He does not endorse an indiscriminate prescribing pattern of cardiac CTs, he added.

“Our study used equipment that may not be available in the community, but only at larger referral centers. In low-risk patents, a simple exercise treadmill test without imaging is probably the best test after all because the probability of disease is so low,” he said. “Only patients of intermediate risk features are most likely to benefit from cardio CT scanning if they have symptoms suggestive of coronary artery disease.”

Johns Hopkins’ next studies are aiming at investigating the utility of CT to replace cardiac catheterization, “which would be a great achievement,” Zadeh said.