Background: Cardiac troponins are important markers for diagnosis of acute myocardial infarction (AMI) in general population; however, chronically-elevated troponins levels are often seen in patients with renal insufficiency, which reduce their diagnostic accuracy. The aim of our study was to access the diagnostic values of initial high-sensitive cardiac troponin T (hs-cTnT) and relative change of hs-cTnT for AMI in patients with and without renal insufficiency.
Methods: Cardiac care unit patients with elevated hs-cTnT levels in 2017-2018 were enrolled. Receiver operating characteristic (ROC) curves were used to evaluate initial hs-cTnT levels and relative changes after 3 h of enrollment for diagnosis of AMI in patients with estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 (low), and eGFR ≥ 60 mL/min/1.73 m2 (normal).
Results: Of 359 patients, 240 patients had low eGFR, and 119 patients had normal eGFR. The area under the ROC curve (AUC) for the initial hs-cTnT levels was 0.58 (95% CI, 0.5-0.65, p = 0.053) among patients with low eGFR and 0.54 (95% CI, 0.4-0.67, p = 0.612) among patients with normal eGFR. AUCs for relative changes of hs-cTnT were 0.82 (95% CI, 0.76-0.88, p < 0.001) in patients with low eGFR and 0.82 (95% CI, 0.71-0.91, p < 0.001) in patients with normal eGFR. Optimal cutoff values for the relative changes in hs-cTnT were 16% and 12% in patients with low eGFR and normal eGFR, respectively.
Conclusions: Relative changes in hs-cTnT levels had better diagnostic accuracy than initial hs-cTnT levels.
Keywords: Acute myocardial infarction (AMI); chronic kidney disease (CKD); renal failure; troponin T.