The aim of this study was to compare EF and cerebrovascular reactivity (CVR) in patients with LS and patients with atherothrombotic stroke (AS).

Methods: The study population consisted of 10 patients with LS (21 days after stroke onset). For these subjects, EF and CVR were compared against an age and gender-matched group consisting of 10 patients with AS. The stroke subtype was classified according to TOAST criteria. EF was assessed using the brachial flow-mediated vasodilatation (FMD). Peak shear stress was used for FMD normalization. Breath-holding test (CVR_BHT=test/baseline mean velocity), hyperventilation (CVR_HV=baseline/test mean velocity) and test with nitroglycerine (CVR_NG= baseline/test mean velocity) were used for CVR evaluation in middle cerebral and basilar artery (using transcranial Doppler).

Results: We observed a significant difference in FMD between LS and AS patients (6.65±0.8% and 10,03±1.1% respectively, p=0.03). The difference in FMD remained after normalization (0.011±0.005s⁻¹ and 0.018±0.007 s⁻¹ respectively, p=0.02). However, no difference in CVR was detected between IS and AS groups (CVR_BHT=1,25±0,17 and 1,24±0,1, CVR_HV=1,34±0,24 and 1,16±0,1, CVR_NG=1,08±0,05 and 1,09±0,1 for LS and AS patients respectively).

Conclusion: Patients with LS demonstrated impaired EF in comparison with patients with AS, however, no difference between these groups was observed in CVR. The impairment of EF in LS patients may reflect a role of endothelial dysfunction in the pathogenesis of LS.