This is a prospective, single centre clinical investigation looking at short (6 months) and long term (24 months) changes in cardiac function and renal function in patients with drug-resistant hypertension post renal sympathetic denervation.

Inclusion Criteria:

• Subject must be able and willing to comply with the required follow-up schedule
• Therapeutic Goods Association approved indications for EnligHTN™ Renal Denervation System
• Subject is ≥ 18 years of age at time of consent Subject has office SBP ≥ 160 mmHg (except for subjects with Diabetes Mellitus who must demonstrate an office SBP of ≥ 150 mm Hg) within 14 days of the procedure ◦Subject is taking ≥ 3 antihypertensive medications concurrently at maximum tolerated dose (this must include one diuretic) or subject has a documented intolerance to at least 2 out of the 4 major classes of anti-hypertensives (ACE/ARB, CCB, Diuretics, Beta Blockers and is unable to take 3 antihypertensive drugs.

Exclusion Criteria:

• Standard CMR exclusions;

  • implanted cardiac device
  • intracranial metallic implants
  • claustrophobia -Gadolinium-specific: estimated GFR <60 mls/min (usual clinical cut-off is <30 mls/min).

• Adenosine-specific:

  • asthma / reactive airways disease
  • >first degree atrioventricular block
  • concomitant use of dipyridamole or theophylline consumption of caffeine within 48 hours of proposed investigation
  • EnligHTN™ Renal Denervation System exclusion criteria:

Subject has an identified cause of secondary hypertension

• Subject has an estimated GFR <45 mL/min per 1.73 m2 using the MDRD formula
• Subject has undergone prior renal angioplasty, indwelling renal stents, and/or aortic stent grafts
• Subject has haemodynamically significant valvular heart disease
• Subject has a life expectancy less than 12 months, as determined by the PI
• Subject is participating in another clinical study Subject is pregnant, nursing, or of childbearing potential and is not using adequate contraceptive methods
• Subject has renal arteries with diameter(s) < 4 mm in diameter