Optimal Cutoff Values and Utility of High-Sensitivity Troponin T and NT-proBNP for the Risk Stratification of Patients with Acute Pulmonary Embolism.

BACKGROUND

Guidelines recommend using high-sensitivity troponin T (hsTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) to risk stratify hemodynamically stable patients with acute pulmonary embolism (PE). However, there are no evidence-based cutoff values defined for this clinical application.

METHODS

We performed a single-center, retrospective cohort study of patients with imaging-confirmed PE and hsTnT and/or NT-proBNP (ElecsysTM, Roche) measured 12 h before or 24 h after PE Response Team (PERT) activation. We excluded hypotensive patients. Our primary outcome was a composite of adverse outcomes or critical interventions within 7 days. We calculated the area under the receiver operating curve (AUC, ROC) for hsTnT and NT-proBNP and determined the optimal cutoffs using the distance from (0,1). We performed a subgroup analysis on patients with PE and right ventricular dysfunction on imaging.

RESULTS

Two hundred thirty-four patients were included in the hsTnT analysis, and 727 in the NT-proBNP analysis. Mean age was 62 years (SD = 17) and 47% were female. The AUC for hsTnT was 0.64 (95% CI, 0.56-0.71) with an optimal cutoff of 46 ng/L, corresponding to a sensitivity of 59% (95% CI, 49-69) and a specificity of 61% (95% CI, 53-69). The AUC for NT-proBNP was 0.56 (95% CI, 0.51-0.61) with an optimal cutoff of 1092 pg/mL, corresponding to a sensitivity of 53% (95% CI, 45-61) and a specificity of 59% (95% CI, 55-63).

CONCLUSION

We identified an optimal cutoff of 46 ng/L for hsTnT and 1092 pg/mL for NT-proBNP, though the AUC for both markers suggests low to moderate performance for the risk stratification of initially hemodynamically stable PERT patients. Use of these biomarkers to risk stratify PE may require reconsideration.