The Effect of Renal Denervation on Renal Flow in Humans

Inclusion Criteria: * Individual is scheduled to undergo renal denervation as standard patient care for resistant hypertension. * Individual is diagnosed with resistant hypertension. Secondary causes and a white coat hypertension are actively excluded. * Individual is ≥18 years of age. * Individual agrees to have all study procedures performed, and is competent and willing to provide written informed consent to participate in this clinical study. Exclusion Criteria: * Individual is excluded from treatment with pRDN . * Individual has an estimated glomerular filtration rate (eGFR) of \<30mL/min/1.73m2, using the MDRD calculation. * Individual has experienced a myocardial infarction, unstable angina pectoris, or a cerebrovascular accident within 6 months of the screening visit, or has widespread atherosclerosis, with documented intravascular thrombosis or unstable plaques. * Individual has any serious medical condition, which in the opinion of the investigator, may adversely affect the safety and/or effectiveness of the participant or the study (i.e., patients with clinically significant peripheral vascular disease, abdominal aortic aneurysm, bleeding disorders such as thrombocytopenia, haemophilia or significant anaemia). * Individual is pregnant, nursing or planning to be pregnant. * Individual has a known, unresolved history of drug use or alcohol dependency, lacks the ability to comprehend or follow instructions, or would be unlikely or unable to comply with study follow-up requirements.