[Validation of a high sensitive troponin 99th percentile obtained in a general hospital]
María Laura Martínez1, Brunella Bianca Bertazzo2, Juan Gonzalez Grima3
1Hospital Privado Universitario de Córdoba. lmartinezbruno@gmail.com.
Insights
The manufacturer's 99th percentile for high sensitivity cardiac Troponin T (hs-cTnT) showed better sensitivity for diagnosing coronary artery disease than a local hospital's percentile. hs-cTnT is crucial for myocardial infarction diagnosis.
Area of Science:
- Cardiology
- Clinical Chemistry
- Diagnostic Medicine
Background:
- High sensitivity cardiac Troponin T (hs-cTnT) is vital for diagnosing myocardial infarction.
- Manufacturer-derived 99th percentiles are standard for hs-cTnT interpretation.
- Local population validation of these cutoffs is essential for accurate diagnosis.
Purpose of the Study:
- To validate the manufacturer's 99th percentile (99F) for hs-cTnT against a local hospital's 99th percentile (99L).
- To compare diagnostic performance using coronary angiography as the gold standard.
- To assess the utility of hs-cTnT in acute coronary syndromes (ACS).
Main Methods:
- Retrospective analysis of hs-cTnT results from 415 patients with ACS undergoing coronary angiography (2015-2018).
- Comparison of diagnostic accuracy metrics (sensitivity, specificity, PPV, NPV) between 99F and 99L.
- Receiver Operating Characteristic (ROC) curve analysis.
Main Results:
- 99F demonstrated higher sensitivity (83.6%) versus 99L (69.7%) for significant coronary artery disease (stenosis >70%).
- Specificity was comparable (44.5% for 99F vs. 58.6% for 99L).
- ROC curve analysis yielded identical results for both cutoffs (0.641).
Conclusions:
- The manufacturer's 99th percentile (99F) is preferred for hs-cTnT interpretation in ACS due to superior sensitivity.
- While sensitivity is lower than previously reported, 99F remains a valuable diagnostic tool.
- Local validation is important, but manufacturer cutoffs offer better diagnostic performance in this cohort.
Introduction:
High sensitivity cardiac Troponin T (hs-cTnT) dosage is recommended for myocardial infarction diagnosis, by applying the 99th percentile obtained from a healthy population by the manufacturer. The objective is to validate the 99th percentile in a population from our hospital (99L), compared with the manufacturer´s 99th percentile (99F) by using coronary angiography as gold standard.
Materials And Methods:
Retrospective analysis of every hs-cTnT (Roche) obtained from patients admitted with acute coronary syndromes (ACS) who underwent coronary angiography between 2015 and 2018.
Results:
415 patients were included for analysis (118 females, 64.2 yo). 99F sensitivity (Sn) for significant coronary artery disease (stenosis >70%) was 83.6%, with a specificity (Sp) of 44.5%. Positive predictive value (PPV) and negative predictive value (NPV) were 77% and 55% respectively. 99L Sn was 69.7% and Sp 58.6%. PPV was 79% and NPV 46%. ROC curve was 0.641 for 99F and 0.641 for 99L.
Conclusion:
Given the importance of hs-cTnT in ACS diagnosis, the 99F should be the preferred upper reference limit since the sensitivity is better, although lower compared to prior studies.
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