High sensitivity troponin assays are useful for ruling out acute MI quickly, an expert says, with new research showing they have a very high negative predictive value.
Undetectable high-sensitivity troponin (hs-cTnT) at emergency presentation had a 100% negative predictive value (CI: 98.1% to 100%), a study found.
The US researchers evaluated 703 patients with chest pain, of whom 130 had AMI – none of whom initially had undetectable hs-cTnT on the Roche Diagnostics test.
Writing in the Journal of the American College of Cardiology, the authors said the test could be used to rule out AMI, identifying patients at low risk of adverse events.
“Pending further validation, this strategy may reduce the need for serial testing and empirical treatment, enabling earlier reassurance for patients and fewer unnecessary evaluations and hospital admissions,” they wrote.
Professor Joseph Hung, consultant cardiologist at Perth’s Sir Charles Gairdner hospital agreed the test could be useful for early AMI rule-out.
“While this represents and opportunity, the downside is that specificity is decreased, and this means clinicians must assess if there is a rise or fall in level – particularly in the context of the patient’s clinical presentation – before making a diagnosis of AMI,” he said.
He noted that up to 50% of the normal population would have detectable levels of troponin above the 99 percentile cut-off.
J Am Coll Cardiol 2011; 58:1332-39
http://www.sciencedirect.com/science/article/pii/S0735109711024247