Abstract 17343: Median Levels and 99th Percentiles of High-Sensitive Troponin T in Different Groups of Chest Pain Patients in the Emergency Department
Background: The 99th percentile of troponin in healthy individuals has been defined as decision limit for the diagnosis of acute myocardial infarction (AMI) in current guidelines. The median levels and 99th percentiles of troponin in different groups of patients presenting with chest pain in the real world however are unknown. The introduction of sensitive troponin assays allows the accurate determination of median levels and 99th percentiles of troponin in these patient groups.
Methods: In a prospective, international multicenter study, high-sensitive cardiac troponin T (hs-cTnT) was measured at admission in 1181 patients presenting to the emergency department with chest pain. The final diagnosis was adjudicated by two independent cardiologists using all available medical records pertaining to the patient. The 99th percentile of the hs-cTnT assay in healthy individuals is 14 ng/l.
Results: The adjudicated final diagnosis was AMI in 187 patients (16%), unstable angina in 164 patients (14%), cardiac symptoms of origin other than coronary artery disease in 155 patients (13%), non-cardiac symptoms in 572 patients (48%), and symptoms of unknown origin in 103 patients (9%). Median levels of hs-cTnT at admission in these diagnostic groups were 115 ng/l, 11 ng/l, 13 ng/l, 6 ng/l and 9 ng/l, while the 99th percentile of hs-cTnT observed in these groups were 5195 ng/l, 157 ng/l, 310 ng/l, 50 ng/l and 248 ng/l (p<0.001 for comparison).
Conclusions: Real world chest pain patients, regardless of the underlying cardiac or non-cardiac disease, have markedly higher levels of hs-cTnT compared to the reference values measured in healthy individuals. In especial, the 99th percentile of hs-cTnT in non-cardiac chest pain patients is more than 3 times higher than the 99th percentile in healthy individuals, which is currently recommended as decision limit in the diagnosis of AMI. These observations are important when assessing chest pain patients in daily practice.
- © 2010 by American Heart Association, Inc.