1Universitäres Herz- und Gefäßzentrum Hamburg Klinik für Kardiologie Hamburg, Deutschland; 2Universitäres Herz- und Gefäßzentrum Hamburg Allgemeine und Interventionelle Kardiologie Hamburg, Deutschland
Objective: The differentiation of acute and chronic myocardial injury in patients presenting to the emergency department is challenging. If the combination of different high sensitivity cardiac troponin (hs-cTn) assays helps in distinguishing acute from chronic injury is unknown. In the current analysis we therefore tested the diagnostic performance of the ratio of three established hs-cTn assays.
Methods: In 1872 patients with suspected myocardial infarction cTn was serially measured at three timepoints (0h, 1h and 3h) using the Atellica IM hs-cTnI (Siemens Healthineers, Germany), the Architect hs-cTnI (Abbott Diagnostics, USA) and the Elecsys hs-cTnT (Roche Diagnostics, Switzerland) assays. Final diagnoses were independently adjudicated by two cardiologists according to the 4th universal definition of myocardial infarction. The ratios of Atellica hs-cTnI, Elecsys hs-cTnT, and Architect hs-cTnI were compared and the area under the Receiver Operating Characteristic curves (AUC) for each ratio were calculated.
Results: Acute injury was present in 410, chronic injury in 467 and no injury was found in 995 patients. As depicted in Table 1 patients with acute injury showed higher Atellica hs-cTnI to Elecsys hs-cTnT ratios than chronic injury patients. The difference was even more pronounced at 1h and 3h after presentation. The same distribution was found for the Architect hs-cTnI to Elecsys hs-cTnT ratios. The differences in Atellica hs-cTnI to Architect hs-cTnI ratios between acute and chronic injury were only modest. Patients without myocardial injury showed similar ratios to chronic injury patients. Consequently, the diagnostic performance to distinguish acute from chronic injury at presentation was higher using the hs-cTnT to hs-cTnI ratios: The Area under the ROC curve for the (AUC) Atellica hs-cTnI to Elecsys hs-TnT ratio was 0.82 (95% CI 0.79-0.84) and the AUC for the Architect hs-cTnI to Elecsys hs-cTnT ratio was 0.79 (95% CI 0.76-0.82). The Atellica hs-cTnI to Architect hs-cTnI ratio reached significantly lower AUC values (0.61 (95% CI 0.57-0.65), p<0.001) (Figure1).
Conclusion: The ratio of hs-cTnI to hs-cTnT is higher in acute than in chronic myocardial injury and hence, might be helpful to discriminate acute and chronic myocardial injury.
Table 1: Ratios of troponin results in patients with acute, chronic and without myocardial injury
|
|
Acute Injury N=410 |
Chronic Injury N=467 |
Non-Injury N=995 |
p-value | |
|
Atellica hs-cTnI/ Elecsys hs-ctnT |
0h |
2.6 (1.2, 7.0) |
0.7 (0.4, 1.1) |
0.7 (0.5, 0.9) |
<0.001 |
|
1h |
3.9 (1.6, 8.7) |
0.7 (0.4, 1.2) |
0.8 (0.5, 1.0) |
<0.001 | |
|
3h |
5.4 (2.0, 10.4) |
0.7 (0.4, 1.4) |
0.8 (0.6, 1.1) |
<0.001 | |
|
Architect hs-cTnI/ Elecsys hs-cTnT |
0h |
2.1 (1.0, 5.6) |
0.6 (0.4, 1.1) |
0.6 (0.4, 1.0) |
<0.001 |
|
1h |
2.7 (1.3, 6.1) |
0.7 (0.4, 1.2) |
0.6 (0.4, 1.0) |
<0.001 | |
|
3h |
4.2 (1.7, 8.7) |
0.7 (0.4, 1.2) |
0.7 (0.5, 1.1) |
<0.001 | |
|
Atellica hs-cTnI/ Architect hs-cTnI |
0h |
1.2 (0.9, 1.6) |
1.0 (0.8, 1.3) |
1.2 (0.9, 1.3) |
<0.001 |
|
1h |
1.3 (1.0, 1.7) |
1.0 (0.8, 1.3) |
1.2 (0.9, 1.4) |
<0.001 | |
|
3h |
1.2 (1.0, 1.5) |
1.1 (0.9, 1.3) |
1.2 (0.9, 1.4) |
<0.001 |
Median and interquartile ranges (25th, 75th percentile) are given. The p-value is calculated using a Chi-squared test for the difference of acute and chronic injury.
Figure 1: Receiver Operating Characteristic (ROC) curves for the differentiation of acute and chronic myocardial injury at 0h