Outcomes in patients admitted for chest pain with renal failure and troponin I elevations

Background The significance of troponin I (TnI) elevations in patients with renal failure (RF) admitted for possible myocardial ischemia is unclear. We therefore compared outcomes in patients with and without TnI elevations based on renal function. Methods Consecutive patients without ST elevation admitted for exclusion of ischemia underwent serial assessment of cardiac markers including TnI. Coronary angiography, significant disease, and revascularization were determined, and 1-year cardiac mortality and all-cause mortality were assessed. Mortality was assessed based on TnI elevations in patients with no (creatinine clearance [CrCl] ≥60 mL/min), moderate (CrCl 30-59 mL/min), and severe (CrCl <30 mL/min) RF. Results Troponin I elevations were present in 17% of the 3774 consecutive patients and were significantly more frequent in patients with RF (CrCl <30 mL/min: 26%; CrCl 30-59 mL/min: 19%; CrCl >60 mL/min: 13%, all P ≤ .01). Coronary angiography was performed significantly less frequently in patients with RF, whether TnI elevations were present. One-year all-cause mortality increased with both RF and TnI positivity (TnI [+] vs TnI [−], CrCl <30 mL/min: 52% vs 26%; CrCl 30-59 mL/min: 21% vs 14%; CrCl >60 mL/min: 8.9% vs 4.9%, all P < .001) . Troponin I was the most important independent predictor of mortality in the 3 RF groups (odds ratio 3.3 for CrCl <30 mL/min, 2.2 for CrCl 30-59 mL/min, and 3.3 for CrCl >60 mL/min). Conclusions Troponin I elevations identified a high-risk cohort, and its prognostic value was not diminished in patients with RF.