Direct Comparison of Cardiac Troponin T and I Using a Uniform and a Sex-Specific Approach in the Detection of Functionally Relevant Coronary Artery Disease.

BACKGROUND

We aimed to directly compare high-sensitivity cardiac troponin I (hs-cTnI) and high-sensitivity cardiac troponin T (hs-cTnT) in the detection of functionally relevant coronary artery disease (fCAD).

METHODS

Consecutive patients referred with clinical suspicion of fCAD and no structural heart disease other than coronary artery disease were included. The presence of fCAD was based on rest/stress myocardial perfusion single-photon emission computed tomography/computed tomography and coronary angiography. hs-cTnI and hs-cTnT concentrations were measured in a blinded fashion. Diagnostic accuracy was quantified using the area under the ROC curve (AUC) and evaluated both for uniform use in all patients and for sex-specific use in women and men separately. The prognostic end point was major adverse cardiac events (MACEs; cardiovascular death or myocardial infarction) within 2 years. For the prognostic performance, we used a multivariable model comparison with the Akaike information criterion (AIC).

RESULTS

fCAD was detected in 613 of 2062 patients (29.7%) overall, 112 of 664 of women (16.9%), and 501 of 1398 of men (35.8%). hs-cTnI and hs-cTnT had comparable diagnostic accuracy when assessed for uniform use in all patients (AUC, 0.68 vs 0.66; = 0.107) and separately in women (AUC, 0.68 vs 0.63; = 0.068) and men (AUC, 0.65 vs 0.64; = 0.475). However, women required lower rule-out cutoffs to achieve high sensitivity, and men needed higher rule-in cutoffs to achieve high specificity. hs-cTnI and hs-cTnT were strongly and independently associated with MACE within 2 years ( < 0.001), with comparable prognostic accuracies by the AIC.

CONCLUSIONS

hs-cTnI and hs-cTnT provide moderate and comparable diagnostic accuracy. Sex-specific cutoffs may be preferred. The prognostic utility of both troponins is comparable.