High-sensitivity cardiac troponin predicts major cardiovascular events in diabetic patients with critical limb ischemia and foot lesions

Abstract

Background: Diabetic patients with critical limb ischemia (CLI) and foot lesions show a poor prognosis. Optimal risk stratification to guide tailored intervention is still uncertain. The aim of the present study was to assess the prognostic role of high-sensitivity cardiac troponin T (hs-TnT) in such a high-risk population. Methods and Results: Clinical, laboratory, and interventional data, as well as the SPINACH score, were collected. Hs-TnT was measured at hospital admission. All patients were followed up for at least 1 year. The primary endpoint was the cumulative occurrence of major cardiovascular events (MACEs, all-cause death, myocardial infarction, or stroke). The secondary endpoint was all-cause mortality. Overall, 618 patients were included and followed for a median of 981 (557–1,325) days. Diagnosis of coronary artery disease (CAD) was established in 270 (43.7%) patients. Median hs-TnT at admission was 31 (20–59) ng/L, with 525 (85%) patients over the upper reference limit. Hs-TnT values were significantly higher in patients with established CAD (39 vs. 29 ng/L, p < 0.01). Hs-TnT was an independent predictor of MACE (HR 2.440, 95% CI 1.706–3.489, p < 0.001). The best cut-offs were 40 ng/L (AUC 0.711) for patients with established CAD and 25 ng/L (AUC 0.725) for those without. Hs-TnT emerged also as an independent predictor of all-cause mortality. The addition of hs-TnT improved prognostic value of the SPINACH score. Conclusions: Hs-TnT is a powerful biomarker for prognostic stratification of diabetic CLI patients with foot lesions. This is confirmed independently to CAD diagnosis and permits the identification of higher risk patients requiring tailored intervention.