Prognostic value of cardiac troponin T and I elevations in renal disease patients without acute coronary syndromes: a 9-month outcome analysis

Background. Moderate elevations of cardiac troponin (Tn) T, up to levels pr esumably diagnostic for minor myocardial damage, are suspected to be false positive in nearly 0.3 of end-stage renal disease (ESRD) patients undergoin g haemodialysis (HD). It is not clear whether cardiac TnI is superior to Tn T in those patients, if differences between ESRD and pre-ESRD occur, and wh at the prognostic meaning of these troponin elevations might be. Subjects and methods. We examined 40 chronic renal-disease patients [56.4 S D 13.9 years; 22 male, 18 female) without evidence of an acute coronary syn drome (ACS) for at least 28 days prior to the investigation. Cardiac status was determined by history, physical examination, ECG and echocardiography. Patients were divided into subgroups with HD (n=20) and without HD (n = 20 ). Patients without HD had a mean creatinine clearance (CC) of 13.45 ml/min . Tn were measured by immunoassay techniques. TnT was compared to two diffe rent TnI tests (TnID, TnIB), CK/CKMB activity and myoglobin (MYO) concentra tions. In all patients, a 9-month follow-up for acute myocardial infarction , re-hospitalization, and death was completed. Results. None of the troponins significantly predicted patient outcome. Tn did not correlate with CC (r<0.6). Applying the lowest reported threshold v alues for all tests in the HD group, 0.3 patients were positive for TnT, 0. 55 patients were positive for TnID, and 0.15 for TnIB. In the group without I-ID, 0.2 patients were positive for TnT and TnID and 0.15 for TnIB. Conclusions. Moderate elevations of cardiac troponins are common in clinica lly stable patients with renal disease and are neither diagnostic for an ac ute coronary syndrome nor predictive of outcome. It is concluded that incre ased troponins in asymptomatic renal patients are of questionable value for risk stratification, most probably due to unspecific elevations.