Baroloop Multicenter Trial (Baroloop MCT)

Inclusion criteria

• Aged 18 years or older.
• 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.
• 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.
• 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.
• Willingness and ability to comply with follow-up requirements.
• Signed informed consent.

Exclusion criteria

• 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).
• Any patient with a history of injury to the vagus nerve or its branches (e.g., the recurrent laryngeal nerve).
• Secondary causes of hypertension.
• Calculated eGFR \< 30 mL/min/1.73m2.
• Type 1 diabetes mellitus or poorly controlled type 2 diabetes mellitus (HbA1c \> 10%).
• Requirement for chronic oxygen therapy or mechanical ventilation.
• Untreated (no CPAP therapy) sleep apnea (AHI \> 15)
• Morbid obesity, defined as Body Mass Index \>40 kg/m2 or arm circumference 46 cm.
• Pacemaker and/or implantable defibrillators.
• History of transient ischemic accident or cerebrovascular accident during six (6) months prior to screening.
• Symptomatic carotid artery disease or \> 70% occlusion of either carotid artery; any carotid malformation or lesion, a carotid bruit or other abnormal carotid sound.
• 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).
• Limited mobility of the neck secondary to vertebral disease or prior vertebral surgery, including patients who wear a cervical support.
• History of heart failure (NYHA class III-IV).
• Cardiac arrythmias (atrial fibrillation, atrial flutter, etc.) that require anticoagulation if the condition interferes with a consistent measurement of blood pressure.
• Unexplained syncope in the last 6 months.
• History of bleeding disorders, thrombocytopenia, hemophilia, or significant anemia (hemoglobin (Hgb) \< 10 g/dl).
• Current anticoagulation therapy (excluding antiplatelet therapy with aspirin as a sole therapy).
• History of unresolved drug or alcohol use.
• Active treatment of a psychiatric ailment.
• Life expectancy of less than 12 months due to other disease.
• Subject has a condition that, in the opinion of the investigator, precludes participation, including willingness to comply, with all follow-up procedures.
• Participation in another clinical study for which follow-up is currently on-going.
• Women who are pregnant
• Resting heart rateof \< 45 beats/min s, confirmed at both baseline visits.
• Baroreflex failure or autonomic neuropathy
• Symptomatic, uncontrolled bradyarrhythmias
• Atrioventricular block of any grade
• Presence of a vagus stimulator
• Patients who are likely to require magnetic resonance imaging (MRI) of the cervical area
• Occupational exposure to high levels of non-ionizing radiation that may interfere with therapy
• Patients with a limited ability to read, understand and execute adjustment procedures (for example, persons suffering from dementia).
• Likely exposure to diathermy.