Application of Optical Coherence Tomography Angiography Macular Analysis for Systemic Hypertension. A Systematic Review and Meta-analysis

Background Microvascular rarefaction due to hypertension has been linked to disease severity and end-organ complications. Optical coherence tomography angiography (OCTA) has been explored as a potential tool to evaluate the retinal microvascular network in hypertensive patients. Methods PubMed, Scopus, Web of Science, and Cochrane were systematically searched to 10th of September of 2021, along with a manual search. Studies that used OCTA as a primary diagnostic method to evaluate the macular microvasculature of hypertensive patients were included. Meta-analysis was performed using a random-effects model. Primary outcomes were macular vessel density (VD) and foveal avascular zone (FAZ) at the superficial and deep capillary plexus. Results Of 947 screened articles, 9 were found eligible for qualitative and quantitative analysis. VD in hypertensive patients was reduced when compared with controls in the fovea (0.93, 95% confidence interval [CI] 0.87-0.99, P = 0.023) and the parafovea (0.95, 95% CI 0.93-0.97, P < 0.001) of the superficial capillary plexus. FAZ was larger in the deep plexus of hypertensive patients (1.10, 95% CI 1.03-1.18, P = 0.003). VD reduction was found in patients with worsening blood pressure control in 3 studies and prolonged disease in 2 studies. Conclusions Microvascular rarefaction of the macula is found in hypertensive patients with a reduction of foveal and parafoveal VD and an increase of FAZ area. Disease duration and severity might be related to a microvascular rarefaction. OCTA could offer a novel tool for the assessment and follow-up of hypertensive patients.