The Measurement of Cardiac Troponin T(cTnT) and Troponin I(cTnI) in Maintenance Dialysis Patients

Lee, Sang Ill; Kim, Hyang; Youn, Joong Won; Kim, Hyun Seung; Sung, Ki Chul; Lee, Kyu Beck; Park, Hyo Soon

Abstract

BACKGROUND: Despite of the high prevalence of cardiac disease, diagnosing and predicting myocardiac infarction in maintenance dialysis patients may be difficult. The availability of cardiac troponin T (cTnT) and cardiac troponin I(cTnI) offered promise for improving the accuracy of myocardial injuries in the ESRD patients. We hypothesized that cardiac troponin T and I might be useful markers of myocardial injury for patients with dialysis.
METHODS
We examined several clinical parameters to identify factors that determine cTnT and cTnI in dialysis patients. The study included 63 patients who had been on dialysis without evidence of myocardial damage for minimum 3 months. Patients were assessed using demographic, cardiac and atherogenic indices including CPK, CK-MB, CK index, LDH, homocysteine, total cholesterol, triglyceride and serum albumin level. All patients were undertaken EKG and echocardiography. Serum levels of cTnT and cTnI were measured by electrochemiluminescence immunoassay(ECL) and chemilumino immunoassay(CLIA) method. We estimated the correlation between cTnT and cTnI with several parameters by using Pearson correlation, linear correlation and Chi- square analysis.
RESULTS
The results are summarized as follows : The positivity of serum cTnT was higher in HD patients than CAPD(32% vs. 18%). But there was no significance statistically. Serum cTnI was elevated(>or=0.1 ng/mL) in only one HD patient. Serum cTnT inversely correlated with serum albumin levels (p < 0.05). The positivity of serum cTnT showed statistically significant correlation with underlying diabetic patients than non-diabetic patients(39% vs. 8%, p < 0.05). Serum cTnI was elevated(>or=0.1 ng/mL) in only one diabetic patient. We could not find the significant correlation between serum cTnT and cTnI with age, sex, dialysis mode, duration of dialysis, serum CPK, CK-MB, CK index, LDH, homocysteine, total cholesterol and triglyceride.
CONCLUSION
Because cTnT revealed significant correlation with serum albumin and underlying diabetes mellitus. So we speculated that cTnT possibly might be a helpful marker as a predictor of myocardial event and mortality in maintenance dialysis patients. But we can not exclude false positivity of cTnT. And we are currently working to define that cTnI might be more specific marker of myocardial damage than cTnT and the development of cardiac event in cTnT-positive patients.