Uncontrolled high blood pressure can cause heart muscle 'thickening', and this increases the likelihood of complications and death. The high blood pressure explains some but not all of this increase in heart size. This study will investigate the other causes, and will measure the heart muscle 'thickness' very accurately using the latest and most accurate technique called cardiac magnetic resonance imaging (MRI). The best way to treat this heart thickening remains to be determined. We hope to be able to show that by specifically targeting the cause of heart muscle thickening we can reduce its occurrence more effectively than by other standard means of blood pressure treatment

• Hypertension
• Left Ventricular Hypertrophy

• Drug: Bendroflumethiazide 2.5mg OD; Amlodipine 10mg OD
• Drug: Valsartan 160mg OD; Moxonidine 400mcg OD

• Experimental: Neurohormonal stimulatory arm
• Experimental: Neurohormonal inhibitory arm

Inclusion Criteria:

• Recently diagnosed essential hypertension (within 6 months).
• Age 25 to 80 years; Weight < 100kg.
• Sinus rhythm without significant ventricular or atrial ectopy.

Exclusion Criteria:

• Current angiotensin II receptor antagonist or ACE Inhibitor treatment.
• Contra-indication to any of the protocol anti-hypertensive agents.
• Angina requiring treatment with a Beta blocker or calcium antagonist
• Any disease affecting the autonomic nervous system e.g. congestive cardiac failure, diabetes, neurological disease, malignancy, pregnancy.
• Contraindication to MRI (pacemaker, intra-orbital debris, intra-auricular implants, intra-cranial clips, history of claustrophobia, inability to lie supine for 15 minutes etc).