What do we do?

My name is Walter van der Merwe and I am a specialist physician. I have worked for 30 years in the public hospital system in New Zealand, but from 23 July 2014 I have been  in full-time private practice..

I have a strong interest in and extensive experience with management of hypertension1-14  (high blood pressure) and am (I think) the only medical specialist in New Zealand offering a specific hypertension service in private. Over the past 9 years I have treated (or directly supervised the management of) over 2000 patients with difficult or resistant hypertension.

Why did I start these clinics?

High blood pressure is the most common modifiable risk factor for cardiovascular disease and death. About 26% of the adult population of New Zealand is hypertensive. Many of these individuals are not even on treatment, but even among those who are, a significant minority do not achieve their target blood pressure levels, and among those there are a group with very difficult blood pressure that does not seem to respond even to multiple drug therapy. These individuals (with blood pressure not at target) are at high risk of heart attack, stroke, heart failure, and kidney disease, and can expect on average to lose 5-6 years of their life expectancy.

GP's see and treat most of the hypertension in New Zealand, but when they are struggling to manage their most difficult cases, they really haven't had anyone to ask or anywhere to send them. There used to be Hypertension Clinics in some of the larger centres in New Zealand, but these no longer exist (the Auckland Hospital hypertension clinic closed in 1992 for example). Cardiology and general medical clinics aren't really set up to deal with difficult or resistant hypertension, and in my observation do it quite poorly and don't provide much assistance to the GP. Endocrinologists can help with the minority of cases who have underlying endocrine causes of hypertension, but aren't that good at managing difficult essential hypertension (the majority of cases). Having said that, I am currently diagnosing more cases of endocrine hypertension (principally primary aldosteronism - Conn's syndrome) than anypne else in New Zealand.

I believe passionately that there is a need for a specialist service catering to the needs of the patients with difficult or resistant hypertension (and their GP's), and that is the service that I wish to provide. I offer to:-




Walter van der Merwe


Other interests

Renal Medicine (Nephrology)

I am a very experienced nephrologist and am happy to see patients in my clinic with any form of renal disease.

Metabolic Workup and Medical Management of Kidney Stones

I have a particular interest in area which is not generally done all that well by the urologists and would welcome referral of your patients with recurrent kidney stones.                                                                                          

1. Establishment of a difficult hypertension clinic in Whangarei, New Zealand: the first eighteen months. van der Merwe W. NZ Med J.2008;121:63-72

2. Nurse titration clinics to achieve rapid control of blood pressure.Taylor D, van der Merwe V, van der Merwe W. NZ Med J.2012:125:31-40

3.Malignant Hypertension: A preventable emergency. van der Merwe W, van der Merwe V. NZ Med J.2013;126:1380.

4. Should all hypertensive patients be screened for primary aldosteronism? Chan PL, van der Merwe V, van der Merwe W. J.Hypertens. (open-access) 2014;3:1.

5. Thiazide Intolerance - a New Zealand perspective. van der Merwe W, Cicovic S, van der Merwe V. J.Hypertens. (open access) 2014;3:1.

6. Ambulatory vs office blood pressure monitoring in renal transplant recipients. Ahmed J, Ozorio V, Farrant M, van der Merwe W. J Clin Hypertens 2015;17:46-50

7. Hypertension in young adults (letter). NZ Med J 2015;128:75-77

8. Difficult hypertension specialist utilising a nurse specialist: a cost-efficient model for the modern era? vander Merwe W, van der Merwe V. J.Clin.Hypertens 2015;17:732-736

9. May we at least have a civilised discussion about primary aldosteronism in New Zealand? (letter). van der Merwe W, van der Merwe V. NZ Med J 2015;128:1419

10. Van der Merwe WM. Diastolic pressure above optimal is the most important predictor of subsequent hypertension in normotensive patients younger than 50 years (commentary). J.Clin.Hyertens.2017:00;1-2

 11. Van der Merwe WM. Long-term efficacy and tolerability of azilsartan medoxomil/chlorthalidone vs olmesartan medoxomil/hydrochlorothiazide in chronic kidmey disease (commentary). J Clin Hypertens 2018;20 (4):703 -4

12. Van der Merwe WM. Utility of fixed-dose single tablet drug combinations in Cameroonians with type 2 diabetes and newly diagnosed hypertension (commentary). J Clin Hypertens. 2019:21:1009-1010

13.Van der Merwe WM. Ambulatory blood pressure monitoring and management of hypertension at a cardiac clinic in Kumasi Metropolis, Ghana (commentary). J.Clin.Hypertens.2020;22:614-615

14. Talreja H, Dawes M, Supershad S, Rabindranath K, Fisher J, Vallapil S, van der Merwe V, Wong L, van der Merwe W, Paton J. A consensus statement on the use of angiotensin receptor blockers and angiotensin converting enzyme inhibitors in relation to Covid-19 (coronavirus disease 2019). NZMJ 2020 (in publication)