Renal denervation reduces retinal arterial remodeling in patients with treatment resistant hypertension and type 2 diabetes mellitus

Objective: Renal denervation has been shown to be a safe and effective method to lower blood pressure (BP) in patients with uncontrolled treatment resistant hypertension (TRH). Patients with TRH and T2DM typically show hypertrophic arteriolar remodeling, which is associated with the development of early target end-organ damage. By using the retinal vasculature as a mirror of vascular remodeling in the systemic circulation, arteriolar remodeling can be non-invasively assessed with Scanning Laser Doppler Flowmetry (SLDF). In this analysis we assessed the impact of RDN on retinal arteriolar remodeling in patients with TRH and T2DM. Design and method: Retinal arteriolar remodeling was assessed using SLDF together with office and 24-hour ambulatory BP before and 6 as well as 12 months after renal denervation in 22 patients with TRH and T2DM. All patients participated in the investigator initiated study program “Renal Denervation in Treatment Resistant Hypertension” (NCT01687725). SLDF allows confocal measurement of the retinal arteriolar parameters, such as outer (OD) and inner (ID) diameter. Based on ID and OD the following parameters of arteriolar remodeling are derived: retinal arteriolar wall thickness (WT), wall-to-lumen ratio (WLR), and retinal arteriolar crosssectional area (CA). Results: Retinal arteriolar parameters were analysed in 18 male and 4 female patients with 6.5 antihypertensive medications on average. There was a significant reduction of systolic and diastolic 24-hour ambulatory as well office BP 6 as well as 12 months after RDN (table 1). In 77.3% of the patients number of antihypertensive medications was reduced. We found a reduction of hypertrophic retinal arteriolar remodeling and also a reduction of WLR 12 months after RDN (table 1). Of note, no significant changes of retinal arteriolar remodeling were found 6 months after RDN. Conclusions: In very high-risk patients with TRH and T2DM endovascular RDN reduced retinal arteriolar remodeling and retinal wall-to-lumen ratio, a prognostic marker of further end-organ damage. Whereas BP-changes already occurred 6 months after RDN, changes in retinal arteriolar remodelling were observed 12 months after RDN. We conclude that after RDN reversal of arteriolar remodeling happens slowly and requires long-term effective BP control.