Rheos® Pivotal Trial

Inclusion Criteria: * Be at least 21 years of age and no more than 80 years of age. * Have been assessed with bilateral carotid bifurcations that are easily interrogated by carotid duplex ultrasound and are below the level of the mandible. * Office cuff systolic blood pressure greater than or equal to 160 mmHg and have a diastolic blood pressure greater than or equal to 80 mmHg as well as a 24-hour ambulatory systolic blood pressure greater than or equal to 135 mmHg despite at lest one month of maximally tolerated therapy with at least three anti-hypertensive medications, of which at least one must be a diuretic. * Must have completed the drug compliance questionnaire and have been judged to be compliant with medications. * For subjects that have had prior bariatric surgery, they must be at least 1 year post-surgery and at a stable weight. * If female, the subject must be surgically sterile, or using a medically accepted method of birth control and agree to continue use of this method for the duration of the trial. Women of childbearing potential must have a negative serum pregnancy test in the pre-implant blood evaluation. * Must be an appropriate or reasonable surgical candidate. * Have signed a CVRx approved informed consent form for participation in this study Exclusion Criteria: * Have known or suspected baroreflex failure or autonomic neuropathy. * Have an arm circumference greater than 46 cm and/or body mass index of greater than 45. * Have significant cardiac bradyarrhythmias. * Have chronic atrial fibrillation. * Have significant orthostatic hypotension * Had a solid organ or hematologic transplant. * Had a myocardial infarction, unstable angina, syncope, or cerebral vascular accident within the past 3 months. * Have carotid atherosclerosis producing a 50% or greater reduction in linear diameter as determined by ultrasound or angiographic evaluation as determined within 6 months of enrollment in the trial. * Have ulcerative plaques in the carotid artery as determined by ultrasound or angiographic evaluation. * Have prior surgery, radiation, or endovascular stent placement in either carotid sinus region. * Have severe chronic kidney disease as defined by: * Currently undergoing dialysis or dialysis is planned within 3 months of the implant date * eGFR of ≤30 ml/min/1.73m² * Have hypertension secondary to an identifiable and treatable cause other than sleep apnea. * Have clinically significant cardiac structural valvular disease. * Have clinically significant reactive airway disease, chronic obstructive pulmonary disease, and/or primary pulmonary hypertension. * Have an uncontrolled comorbid medical condition that would adversely affect participation in the trial. * Have a clinically significant psychological illness that would prohibit the subject's ability to meet the protocol requirements * Are currently taking an imidazolone receptor agonist * Are unable or unwilling to fulfill the protocol medication compliance and follow-up requirements. * Have an active infection within the last month. * Have a co-morbid condition that reduces life expectancy to less than one year. * Are enrolled in another concurrent clinical trial, without prior approval of CVRx.