Microcirculatory abnormalities of the conjunctiva and retina in patients with arterial hypertension

Background. Arterial hypertension is associated with systemic microcirculatory dysfunction, which represents one of the early pathogenetic mechanisms of target organ damage, even in patients who have achieved target blood pressure levels. Ocular microcirculation, which is highly sensitive to systemic hemodynamic and metabolic changes, is regarded as an accessible model for noninvasive assessment of the microvascular bed. Purpose: To assess abnormalities of conjunctival and retinal microcirculation in patients with arterial hypertension. Materials and methods. This single-center observational study, conducted from November 2023 to October 2025, included 22 patients with stage I–III arterial hypertension and 30 healthy volunteers. All participants underwent conjunctival laser Doppler flowmetry (LDF) and optical coherence tomography angiography (OCTA) of the macular region, including analysis of vessel density, perfusion parameters, and the area of the foveal avascular zone (FAZ). Results. Compared with controls (n = 30), patients with arterial hypertension (n = 22) showed reduced conjunctival perfusion (M) (19.88 ± 2.94 vs 21.80 ± 1.17 perfusion units, p = 0.001), reduced blood flow variability (σ) (2.04 ± 0.78 vs 4.91 ± 0.20 perfusion units, p < 0.001), and a lower endothelial component of regulation (5.6 ± 0.56 % vs 9.67 ± 3.34 %, p = 0.001). OCTA revealed a decrease in the superficial retinal capillary plexus vessel density (48.19 ± 1.59 % vs 49.06 ± 0.85 %, p = 0.01) and an increase in interocular asymmetry of this parameter (4.00 ± 4.42 % vs 2.06 ± 1.62 %, p = 0.016) in patients with arterial hypertension. Correlations were found between M and retinal microcirculatory parameters (r ranging from −0.348 to 0.367; p < 0.05). Conclusion. CTA and LDF provide complementary information on structural and functional microcirculatory changes. Their combined use may help detect early vascular remodeling in patients with arterial hypertension and support monitoring of target organ damage.

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