Troponin I testing in dialysis patients presenting to the emergency room: Does troponin I predict the 30-day outcome?

Background: Troponins are often measured in acutely ill chronic dialysis patients admitted to the emergency room, irrespective of their clinical presentation. The significance of an elevated troponin level in this setting is unclear. Methods: We identified all chronic dialysis patients presenting over 1 year to a tertiary care hospital emergency room who also had at least one cardiac troponin (cTnl) level determination. We evaluated presenting complaints, risk factors for cardiac disease, cTnl levels, and major cardiac events (MCE; occurrence of cardiovascular death, myocardial infarction, de novo heart failure, or coronary revascularization) within 30 days by chart review in 149 patients (79 on hemodialysis, 70 on peritoneal dialysis). Results: Chest pain was documented in only 29% of the patients. Twenty-two patients (15%) experienced an MCE. The incidence of an MCE was the same in patients with and without chest pain. A cTnl level 1 > 0.1 ng/l was a significant predictor of an MCE (odds ratio 15.2, 95% confidence interval CI 5.26, 43.6). The likelihood ratios for MCEs were 0.32 (CI 0.16, 0.63) for a cTnl level < 0.1 ng/l, 0.72 (CI 0.09, 5.5) for cTnl concentrations 0.1-0.3 ng/l, 7.8 (CI 4.2, 15) for a cTnl level > 0.3, and 11.7 (CI 4.4, 31) for a cTnl concentration > 2.0 ng/l. Conclusion: In acutely ill chronic dialysis patients presenting to a hospital emergency room, an elevated cTnl level indicates an increased 30-day cardiac risk, regardless of their clinical presentation. Copyright (c) 2006 S. Karger AG, Basel.