Inclusion Criteria:
1. Aged 18 years or older.
2. Persistent office systolic blood pressure (SBP) ≥ 140 mm Hg and diastolic blood pressure (DBP) \> 90 mm Hg on antihypertensive medicines on two visits separated by a minimum of four weeks.
3. Mean 24-hour systolic ABPM ≥ 130 mm Hg and mean 24 hour diastolic ABPM ≥ 80 mm Hg conducted after direct observed therapy to confirm that antihypertensive medicines were taken as prescribed during the ABPM measurement.
4. Stable drug regimen of 3 antihypertensive medicines consisting of a reninangiotensin blocker (ACE) or Angiotensin II Receptor Blocker (ARBs), a calcium channel blocker (CCB), and a diuretic for 4 weeks at treatment.
5. Willingness and ability to comply with follow-up requirements.
6. Signed informed consent.
Exclusion Criteria:
1. Any patient in whom access to the vagal nerve is limited by the size of the vagus (a size not compatible with the baroloop cuff).
2. Any patient with a history of injury to the vagus nerve or its branches (e.g., the recurrent laryngeal nerve).
3. Secondary causes of hypertension.
4. Calculated eGFR \< 30 mL/min/1.73m2.
5. Type 1 diabetes mellitus or poorly controlled type 2 diabetes mellitus (HbA1c \> 10%).
6. Requirement for chronic oxygen therapy or mechanical ventilation.
7. Untreated (no CPAP therapy) sleep apnea (AHI \> 15)
8. Morbid obesity, defined as Body Mass Index \>40 kg/m2 or arm circumference 46 cm.
9. Pacemaker and/or implantable defibrillators.
10. History of transient ischemic accident or cerebrovascular accident during six (6) months prior to screening.
11. Symptomatic carotid artery disease or \> 70% occlusion of either carotid artery; any carotid malformation or lesion, a carotid bruit or other abnormal carotid sound.
12. Prior surgery, radiation therapy or scarring in the neck in the region of the carotid artery (e.g., patients with a tracheostomy, extensive thymectomy or thyroid surgery).
13. Limited mobility of the neck secondary to vertebral disease or prior vertebral surgery, including patients who wear a cervical support.
14. History of heart failure (NYHA class III-IV).
15. Cardiac arrythmias (atrial fibrillation, atrial flutter, etc.) that require anticoagulation if the condition interferes with a consistent measurement of blood pressure.
16. Unexplained syncope in the last 6 months.
17. History of bleeding disorders, thrombocytopenia, hemophilia, or significant anemia (hemoglobin (Hgb) \< 10 g/dl).
18. Current anticoagulation therapy (excluding antiplatelet therapy with aspirin as a sole therapy).
19. History of unresolved drug or alcohol use.
20. Active treatment of a psychiatric ailment.
21. Life expectancy of less than 12 months due to other disease.
22. Subject has a condition that, in the opinion of the investigator, precludes participation, including willingness to comply, with all follow-up procedures.
23. Participation in another clinical study for which follow-up is currently on-going.
24. Women who are pregnant
25. Resting heart rateof \< 45 beats/min s, confirmed at both baseline visits.
26. Baroreflex failure or autonomic neuropathy
27. Symptomatic, uncontrolled bradyarrhythmias
28. Atrioventricular block of any grade
29. Presence of a vagus stimulator
30. Patients who are likely to require magnetic resonance imaging (MRI) of the cervical area
31. Occupational exposure to high levels of non-ionizing radiation that may interfere with therapy
32. Patients with a limited ability to read, understand and execute adjustment procedures (for example, persons suffering from dementia).
33. Likely exposure to diathermy.
