A test used to diagnose the rare condition of aortic dissection may tell radiologists something else important about the patients who undergo that scan.
Visual coronary artery calcium (CAC) scores from CT aortographs (CTAo) and what they can tell doctors about a patient's long-term risk was the subject of a Wednesday presentation by Duan Chen, MD, MS, and Alison Schonberger, MD, both with the Department of Radiology at the Albert Einstein College of Medicine at Montefiore Medical Center in New York.
"We see a lot of patients in the emergency department with severe chest pain and a CT aortograph is one of the tests we do to rule out a very serious diagnosis of an aortic dissection, but only about 2% of those tested are actually experiencing that condition, so we wanted to see what else we could learn from this data that may help our patients," Dr. Chen said. "We were really surprised with the findings."
Researchers studied data on a cohort of patients who received emergency CTAo from 2007 to 2012, examining events including death, aortic dissection, myocardial infarction (MI), cerebrovascular accident and pulmonary embolism. Visual CAC scores were computed from the patient's original images utilizing a validated 12-point scale.
Of the 1,662 patients in the study who had a CTAo, 36% had at least one subsequent documented clinical event, with the most common events being death and myocardial infarction.
"We found an unexpected higher rate of death and non-fatal events," Dr. Schonberger said. "Although these chest CTs were originally performed to rule out an aortic dissection, more people had an MI, stroke, or died, than were diagnosed with an aortic dissection."
The study also included a survival analysis that looked at the association between CAC scores and mortality among these patients and found a strong correlation. In that analysis, the researchers found eight-year mortality for patients with high calcium was much higher (57%), than for those patients without coronary calcium (13%).
Even patients with a CAC score considered low on the scale was twice as likely (25%) to die than a patient with no coronary calcium.
Opportunity for Radiologists to Impact Clinical Care
Drs. Chen and Schonberger are continuing to study the data which controls for age and gender, but does not consider co-morbity factors like smoking or a history of diabetes, and hope other institutions will conduct similar studies.
"We think this is a missed opportunity for radiologists to impact clinical management in acute chest pain patients," Dr. Schonberger said.
Right now, radiologists do not always assign a CAC score on these types of scans, but after conducting this analysis, the doctors said this addition could help communicate necessary next steps for certain patients.
"Patients with negative CT scans for aortic dissection are often discharged without plans for coronary risk assessment," Dr. Schonberger said. "But as we saw, many of these patients are at high risk for having an event and even dying. We believe there is potential for radiologists to aid in clinical management of these patients by reporting coronary calcium scores."