Rheos Feasibility Trial

Inclusion Criteria: 1. Be at least 21 years of age. 2. Have been assessed to have bilateral carotid bifurcations located at or below C3-C4. 3. Have an office cuff systolic blood pressure greater than or equal to 160 mmHg and a 24-hour ambulatory systolic blood pressure greater than or equal to 150 mmHg despite at least one month of full therapy with at least three (3) anti-hypertensive medications, of which at least one (1) must be a diuretic. 4. Must be certified by the investigator hypertension specialist as compliant with taking full doses of medication. 5. Have signed a CVRx approved informed consent for participation in this study. Exclusion Criteria: 1. Have been diagnosed with: * Baroreflex failure * Cardiac bradyarrhythmias * Chronic atrial fibrillation 2. Had a heart transplant 3. Have carotid atherosclerosis producing a 50% or greater reduction in linear diameter as determined by ultrasound or angiographic evaluation as determined within six months of enrollment in the trial. 4. Have Grade C ulcerative plaques in the carotid artery as determined by ultrasound or angiographic evaluation. 5. Have prior surgery or radiation in either carotid sinus region. 6. Currently have implanted electrical medical devices such as cardiac pacing, defibrillation or neurologic stimulation systems. 7. Are pregnant or contemplating pregnancy during the 13-month follow-up period. 8. Currently undergoing dialysis. 9. Have hypertension secondary to a treatable cause. 10. Have clinically significant cardiac valvular disease. 11. Are unable or unwilling to fulfill the protocol medication compliance and follow-up requirements. 12. Are unlikely to survive the protocol follow-up period. 13. Are enrolled in another concurrent clinical trial. \-