Abstract
In patients with end-stage renal disease (ESRD), the early diagnosis of acute myocardial infarction (AMI) is clinically challenging due to chronic baseline elevations of cardiac troponins. This prospective observational study compared the diagnostic accuracy of high-sensitivity cardiac troponin T (hs-cTnT) and high-sensitivity cardiac troponin I (hs-cTnI) in ESRD patients presenting to the emergency department with suspected AMI. We enrolled 342 hemodialysis patients presenting with acute chest pain or dyspnea. Blood samples were collected at presentation (0 hours) and 3 hours later. AMI was adjudicated by an independent clinical consensus committee using clinical, electrocardiographic, and angiographic data. Of the 342 patients, 50 (14.6%) were diagnosed with AMI. At presentation, baseline hs-cTnT exceeded the 99th percentile upper reference limit (URL) in 91.1% of patients without AMI, whereas hs-cTnI was elevated in 48.6%. The area under the receiver operating characteristic curve (AUC) for AMI diagnosis at presentation was significantly higher for hs-cTnI than for hs-cTnT (0.89 vs. 0.78, p < 0.01). Serial testing using a 3-hour absolute change (delta) significantly improved diagnostic specificity for both assays. However, the combination of baseline hs-cTnI with its 3-hour absolute delta yielded the highest diagnostic performance (AUC 0.94). In conclusion, hs-cTnI provides superior diagnostic specificity and overall accuracy compared to hs-cTnT for the early detection of AMI in ESRD patients, reducing false-positive elevations in this high-risk population.
