Prognostic value of biomarkers of ischaemia in patients with peripheral arterial disease following endovascular revascularisation.

Background: Our aim was to evaluate the prognostic value of detectable high-sensitivity cardiac troponin I (hs-cTnI) and ischaemia-modified albumin (IMA) in predicting all-cause death or non-fatal ischaemic events in patients with PAD after endovascular revascularisation of the lower limbs. Patients and methods: Patients who underwent successful endovascular revascularisation for chronic limb-threatening ischaemia (CLTI) or disabling intermittent claudication (IC) were prospectively included. Pre-procedural levels of hs-cTnI and IMA were measured, and patients were followed for one year for the occurrence of the composite outcome of all-cause death, non-fatal myocardial infarction, new-onset angina, non-fatal ischaemic stroke, transient ischaemic attack, or progression of PAD. Outcomes were evaluated using survival analyses. Results: A total of 487 patients concluded the study, of whom 175 (35.9%) experienced the composite outcome. When considering only the clinical presentation of PAD and biomarker values, in patients with CLTI, hs-cTnI above the limit of detection (LoD) conferred an increased risk of the composite outcome compared to hs-cTnI below the LoD (p=0.004), while for IMA we found no significant difference. Outcomes of patients with CLTI and hs-cTnI or IMA below the LoD did not differ from those of patients with IC (p=0.07 and p=0.462, respectively). When adjusting for clinical characteristics and common cardiovascular risk factors in multivariate Cox survival analysis, neither biomarker improved prognostic performance, however IMA emerged as an independent predictor of the composite outcome in patients with CLTI. Conclusions: In patients with PAD who underwent successful endovascular procedure, neither IMA nor hs-cTnI improved risk stratification beyond clinical determinants. However, detection of IMA was an independent predictor of major cardiovascular events or death in patients with CLTI.