The effect of renal denervation on peripheral and cerebral vasoreactivity in patients with resistant hypertension and type 2 diabetes mellitus

Vasoreactivity is fundamental mechanisms of the control of tissue perfusion, that distributes supply of blood flow according to metabolic needs and protecting the organs from changes in systemic blood pressure (BP). The presence of vascular risk factors such as hypertension (HTN) and diabetes mellitus (DM) impairs vasoreactivity, leading to an increased risk of stroke and myocardial infarction. The aim of this study was to evaluate the effect of renal denervation (RDN) on peripheral and cerebral vasoreactivity in patients with resistant HTN (RHTN) and type 2 DM at 6 month after procedure.The assessment of the effect of RDN on peripheral vasoreactivity was performed in 31 patients with RHTN and type 2 DM, participants in single-arm prospective interventional studies (protocol numbers NCT02667912 and NCT01499810 at ClinicalTrials.gov) (mean age 59.1 ± 8.6 years, mean office (systolic/diastolic) BP (SBP/DBP) 167.7 ± 18.5/86.7 ± 16.6 mmHg, HbA1c 7.8 ± 1.8%, 22 (68%) men), of which cerebral vasoreactivity was evaluated in 21 patients with good visualization. All patients underwent ambulatory 24-hour BP. Flow-mediated dilation (FMD) of brachial artery and vasoreactivity of middle cerebral artery (MCA) during both breath-holding and hyperventilation testes were measured by high-resolution ultrasound at baseline and 6 month follow-up.RDN led to a decrease in mean 24-hour BP (SBP/DBP) (from 157.5 ± 18.2/76.5 ± 9.7 to 147.8 ± 15.6/71 ± 12.8mmHg, p = 0.049/0.096) without significant changes in number of antihypertensive drugs (from 4.7 ± 0.9 to 4.5 ± 1.2, p = 0.52). There were increase in FMD (from 3.4 ± 5.5 to 7.7 ± 4.2%, p = 0.004), but vasoreactivity of MCA to hyperventilation and breath-holding test was not changed. The degree of improvement of FMD not correlated with the baseline BP and its change after RDN.According to our results, RDN in diabetic patients with RHTN improved peripheral vasoreactivity regardless of the degree of BP reduction, but did not significantly change cerebral vasoreactivity at 6 month follow up.