Mild troponin I elevation does not predict ischemia on myocardial perfusion imaging

Introduction: Data are limited on the degree of mild troponin I elevation and clinical risk factors in predicting myocardial ischemia. Methods: Hospitalized adult patients who underwent myocardial perfusion imaging (MPI) from 2015 to 2016 at Rochester General Hospital and had mild troponin I elevation (>0.1 and <1.5 ng/mL) were included. Predictors of outcomes were determined using logistic regression model. Results: One hundred and sixty-six patients with mild troponin I elevation who underwent MPI were followed. Mean age was 69.6 ± 12.5 years and 53.0% of the patients were female. Fourteen patients (8.4%) presented with typical chest pain (CP), 60 patients (36.1%) had atypical CP and 92 patients (55.4%) had no CP on presentation. MPI was positive for ischemia in 45 patients (27.1%). There was no difference in peak troponin I level with ischemia versus no ischemia on MPI (0.34 ng/dL [0.13-0.69] vs. 0.23 ng/dL [0.14-0.50], p value 0.254). Atypical CP did not predict the presence of ischemia on MPI (odds ratio [OR] 1.97, 95% confidence interval [CI] 0.91-4.26). Coronary artery disease (CAD) history (age and sex adjusted p value 0.013), diabetes (adjusted p value 0.036), creatinine ≥2 mg/dL (adjusted p value 0.019) and dialysis (adjusted p value 0.006) were statistically significant predictors of ischemia on MPI. Conclusions: In patients presenting with mild troponin I elevation, peak troponin I level did not predict ischemia on MPI. The presence of CAD history, diabetes, elevated creatinine and dialysis were predictors of ischemia on MPI.