COVID-19: ACC Advises Cautions on Use of Troponin, Natriuretic Peptide Tests

Two widely assayed cardiac biomarkers are often elevated in patients with coronavirus infection (COVID-19), for reasons that are still poorly understood, but tests for them shouldn’t be ordered except for standard clinical reasons.

That means assays for troponins and natriuretic peptides should be obtained only for such patients who have clinical signs of acute myocardial Infection (MI) or heart failure, respectively.

Those are top-line messages from a short view posted by the American College of Cardiology (ACC) aimed in part at discouraging unnecessary application of widely-used heart-disease biomarker assays in the unfamiliar times of a global public health emergency.

“The ramifications of downstream testing from random measurement of cardiac biomarkers cannot be discounted. Consults, echocardiograms, CT, or invasive angiograms and other further investigation of abnormal cardiac biomarkers run the risk of exposing healthcare providers and other patients.

“For all those reasons, clinicians should strongly consider reserving measurement of troponin and natriuretic peptide testing for circumstances in which they would add meaningfully to the clinical picture, and where they would significantly alter the management of patients with the virus.”

The assays include those for cardiac troponin (cTn) and either  brain natriuretic peptide (BNP) or N-terminal proBNP (NT-proBNP). Elevations in cTn by high-sensitivity assay (hs-cTn) are even more likely in patients with COVID-19, the article cautions.

The number of “confirmed and presumptive positive” US cases of COVID-19 has reached 10,442 in all 50 states, Washington DC, Puerto Rico, Guam, and US Virgin Islands, the US Centers for Disease Control and Prevention (CDC)reported today.

The World Health Organization (WHO) reported a total of 191,127 cases globally as of March 18, but the picture changes rapidly. Other sources report more than 240,000 cases around the world as of today.

Given the novelty of coronavirus as a public health threat, there are as yet few publications on the cardiovascular implications of COVID-19. However, elevations in the biomarkers are common in acute respiratory distress syndrome (ARDS) in general, and are “associated with an unfavorable course,” the article notes.

“While neither alone is specific for acute MI or heart failure,” Januzzi said, “both biomarkers are prognostic, supporting the contention they are a measure of disease severity, regardless of their lack of a link to MI or heart failure.”

In patients with COVID-19, therefore, “clinicians are advised to only measure troponin or natriuretic peptides if the diagnosis of acute MI or heart failure are being considered on clinical grounds,” the article states.

Moreover, “an abnormal troponin or natriuretic peptide result should not be considered evidence for an acute MI or heart failure without corroborating evidence.”

Januzzi observed that “the ACC is taking a very proactive stance toward education for clinicians during the COVID-19 epidemic.”

For example, the society has helped conduct “daily webinars with colleagues in China to provide best practices for care for our patients as the epidemic is waning in their region, and just as we are starting to see an exponential increase of COVID-19 diagnoses in our hospitals,” he said. “Learning from our Chinese colleagues will be crucial to support our front-line clinicians here in the United States.”