#4835 KIDNEY FUNCTION-SPECIFIC CUT-OFF VALUES OF HIGH-SENSITIVITY CARDIAC TROPONIN T FOR THE DIAGNOSIS OF ACUTE MYOCARDIAL INFARCTION

Abstract

Abstract Background and Aims Acute myocardial infarction (AMI) is the leading cause of death worldwide. Patients with kidney dysfunction have high prevalence of AMI, thus early detection of AMI is necessary. However, in patients with decreased estimated glomerular filtration rate (eGFR), using the traditional cut-off value (14 ng/L) of high-sensitivity cardiac troponin T (hs-cTnT) resulted in lower specificity for diagnosing AMI. Our study aims to determine and validate kidney function-specific cut-off values of hs-cTnT for diagnosing AMI in patients with different degrees of kidney dysfunction. Method This large, multicenter, observational cohort study included 21,912 hospitalized patients who had undergone coronary angiography in 6 clinical centers from 2013 to 2021. The study outcome was the diagnosis of AMI. In the derivation cohort, kidney function-specific cut-off values of hs-cTnT for diagnosing AMI were determined to improve the specificity without the cost of sensitivity, as compared to that using 14 ng/L as the cut-off value in the normal kidney function group. The efficacy of the novel cut-off values was validated in an independent validation cohort enrolled from another clinical center. Results In the derivation cohort (n = 12,900), 3,247 patients (25.2%) had an eGFR <60 mL/min/1.73m2. Even in the absence of AMI, 1485 (50.2%) participants with eGFR <60 mL/min/1.73m2 had a hs-cTnT concentration ≥14 ng/L. Using 14 ng/L as the threshold of hs-cTnT for diagnosing AMI led to a significantly reduced specificity (9.1–52.7% vs. 75.0%) and positive predictive value (15.5–21.1% vs. 28.7%) in patients with kidney dysfunction, as compared with patients with normal kidney function. The kidney function-specific cut-off values (eGFR ≥60 ml/min/1.73m2: 14 ng/L, 60>eGFR≥30 mL/min/1.73m2: 18 ng/L, and eGFR <30 ml/min/1.73m2: 48 ng/L) were determined and remarkably improved the diagnostic accuracy for AMI in participants with different levels of kidney dysfunction (specificity: reach to 52.8–63.0%; positive predictive value: 18.7–33.6%), without compromising sensitivity (96.6–97.9%). The kidney function-specific cut-off values increased the diagnosis accuracy of hs-cTnT for diagnosing AMI in every eGFR subgroup in the independent validation cohort (n = 8,012). Conclusion The kidney function-specific cut-off values of hs-cTnT significantly improved the diagnostic accuracy of AMI in patients with kidney dysfunction, and might be generally useful in clinical practice.