Leukotrienes E4 and B4 and vascular endothelium - New insight into the link between vascular inflammation and peripheral arterial.

Leukotrienes are proinflammatory mediators that participate in the process of atherogenesis and contribute to the development of symptomatic peripheral arterial disease. The aim was to evaluate the relationship between leukotriene E4 (LTE4) and B4 (LTB4) with parameters reflecting endothelial vascular function in patients with chronic lower limb ischemia. This prospective observational study enrolled 50 consecutive patients undergoing endovascular treatment due to chronic lower limb ischemia (Rutherford 3). All participants were followed-up for one year (after 1, 3, 6 and 12 months), with a sequential assessment of urinary LTE4 and LTB4, as well as measures of endothelial and vascular function: Flow-Mediated Dilatation (FMD), Intima-Media Thickness (IMT), corrected Augmentation Index (AI75), Shear Rate (SR), Ankle-Brachial Index (ABI), Toe-Brachial Index (TBI). There was a significant relationship between LTE4 and measures of vascular function: FMD (R2 = 0.69, P < 0.001), IMT (R2 = 0.12, P < 0.01), AI75 (R2 = 0.43, P < 0.001), SR (R2 = 0.48, P < 0.001). Similar findings were noted for LTB4: FMD (R2 = 0.47, p < 0.001), IMT (R2 = 0.23, P < 0.001), AI75 (R2 = 0.61, P < 0.001) and SR (R2 = 0.33, P < 0.001). Alterations in parameters were significantly related: ΔLTE4 vs ΔFMD(R2 = 0.63, P < 0.001), ΔSR (R2 = 0.42, P < 0.001) and ΔLTB4 vs AI75(R2 = 0.40, P < 0.001), SR(R2 = 0. 29, P < 0.001). We conclude, that increasing concentrations of LTE4 and LTB4 are associated with impairment of vascular and endothelial function, which may lead to worse endovascular treatment clinical outcomes.