Research published this week in Radiology suggests troponin-positive patients presenting with acute chest pain could benefit from a protocol that combines triple-rule-out and late contrast-enhanced CT scans.
Elevated troponin levels signal myocardial injury but specifying the root cause of such damage is challenging. And while coronary CT angiography in conjunction with a triple-rule-out (TRO) protocol is a valuable tool for triaging patients with acute chest pain it’s unable to identify nonvascular causes of acute injury.
Experts reasoned that these patients could benefit from a more comprehensive protocol that includes an angiographic CT as well as a late contrast-enhanced (LCE) scan for a more thorough cardiac assessment.
For the observational study, the researchers analyzed 84 troponin-positive patients who presented to emergency departments between June 2018 and September 2020.
Patients with inconclusive diagnoses after clinical evaluation underwent TRO-CT. If that scan was negative for CAD, acute aortic syndrome and pulmonary embolism, patients would then undergo an LCT-CT scan after a 10-minute delay to gauge myocardial extracellular volume fraction and assess for scarring.
Alone, TRO-CT identified obstructive CAD in 35 patients, acute aortic syndrome in one and pulmonary embolism in six.
LCE-CT scans were obtained for the remaining 42 participants. Those scans revealed additional diagnoses of myocarditis (22/42), takotsubo cardiomyopathy (4/42), amyloidosis (3/42), myocardial infarction (3/42), dilated cardiomyopathy (2/42) and inconclusive findings (8/42).
The diagnostic rate increased from 50% with TRO-CT alone to 90% when combined with the LCE-CT.
The authors maintain that this protocol is especially beneficial in emergency settings when obtaining cardiac MRI can be time consuming and cumbersome.
“The one-stop shop examination proposed in this study yields a significant improvement in CT capability to provide a definite diagnosis in the acute chest pain setting,” corresponding author, Antonio Esposito, MD, with the Clinical and Experimental Radiology Unit at San Raffaele Scientific Institute, and co-authors explained. “This protocol can speed up the final diagnosis because it allows radiologists to obtain, from a single CT study, several pieces of information commonly derived from combined CT and MRI examinations.”
You can view the detailed study in Radiology.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She joined Innovate Healthcare in 2021 and has since put her unique expertise to use in her editorial role with Health Imaging.