The ANDORRA study is a, multicenter, prospective, open, randomized, controlled blinded endpoint trial (PROBE) comparing two treatment strategies (renal artery stenting + standardized and optimized medical treatment [SOMT] versus SOMT alone) of 12 months duration in patients with confirmed resistant hypertension (RH) and angiographically proven grade III unilateral or bilateral atherosclerotic renal artery stenosis (ARAS) ≥ 60%.

All eligible patients diagnosed with RH on office BP measurements and unilateral or bilateral ARAS ≥60% on a non-invasive test (CT-angiogram or MR-angiogram) will receive a standardized optimized triple antihypertensive treatment for 4 weeks. After 4 weeks, patients with confirmed RH by ABPM (daytime ABPM ≥ 135 or 85 mmHg) and no clinically significant increase in plasma creatinine from baseline (< 30%) will undergo a renal angiogram to confirm the degree of ARAS ≥60% in diameter.

Immediately after the renal angiography, all patients will undergo flow fractional reserve (FFR) measurements. Once FFR measurements have been done and all criteria are met, patients will be randomized in the angiography room to either renal artery stenting + SOMT (stenting group) versus SOMT (control group) whatever the results of the FFR in a 1:1 ratio. Both groups will continue the SOMT during follow-up.

The SOMT will be prescribed from the inclusion visit until the 6 month-visit after randomization. After randomization, the antihypertensive treatment will be adapted according to the results of home BP (HBP) at monthly visits starting 2 months after randomization. After the 6-month visit, the antihypertensive treatment adaptation will be left at the discretion of the physician in charge of the patient.

Inclusion Criteria:

• Age: 40 to 80 Years
• Men or women
• Supine office BP ≥ 140 and/or 90 mmHg at screening despite a stable medication regimen including full tolerated doses of 3 or more anti-hypertensive treatments of different classes, including a diuretic.
• Unilateral or bilateral ARAS of a main renal artery ≥60% diagnosed by renal CT- angiogram (or MR-angiogram if there is a contraindication to perform CT) performed in the year before
• One or two functional kidney(s) ≥ 70 mm in pole-to-pole length
• eGFR ≥ 20 ml/min/1.73 m² (MDRD formula)
• Signed informed consent
• Social insurance coverage

Inclusion criteria for the renal angiogram procedure:

- RH confirmed by daytime ABPM ≥ 135 or 85 mmHg after 1 month treatment with SOMT at Visit V1.

Inclusion criteria for the randomization:

• Unilateral or bilateral ARAS of a main renal artery ≥ 60% confirmed on renal angiogram by Quantitative Vascular Analysis (QVA)
• Increase in plasma creatinine < 30% after 4-week SOMT

Exclusion Criteria:

• Fibromuscular dysplasia of renal artery or other non-atherosclerotic renal artery stenosis
• Other secondary form of hypertension excluded on the basis of a clinical, hormonological and/or imaging work-up
• Restenosis after a previous renal angioplasty or stenting
• Only a stenosis of an accessory renal artery supplying <1/2 of the ipsilateral renal parenchyma
• Additional indication of ARAS stenting (Malignant hypertension, ≥ 30% increase in plasma creatinine after renin angiotensin system (RAS) blocker or after RAS blocker and diuretic administration, flash pulmonary edema)
• Kidney pole-to-pole length < 70 mm
• Vascular disease precluding access for stenting
• Abrupt vessel closure or dissection after diagnostic angiography
• Contraindication to renal artery stenting according the notice for use of the stents
• eGFR < 20 ml/min/1.73 m² (MDRD)
• History of transient ischemic accident (TIA) or cerebrovascular accident (CVA) during the 3 months prior to visit 1
• History of acute heart failure or heart failure (NYHA class III-IV) within the 3 months prior to visit 1
• History of myocardial infarction, unstable angina, coronary bypass or percutaneous coronary angioplasty during the 3 months prior to visit 1
• Abdominal aortic aneurysm with indication for surgery or EVAR (Endovascular Aneurysm Repair)
• Known history of cholesterol embolism
• Brachial circumference of ≥ 42 cm
• Severe contrast media allergy, not amenable to pre-treatment
• Allergy to aspirin or clopidogrel
• Atrial fibrillation
• Comorbid condition causing life expectancy ≤ 3 years
• Unlikely to co-operate in the study and/or poor compliance anticipated by the investigator
• Participant not affiliated to the French social security
• Pregnancy or breastfeeding
• Guardianship for incapacity