Central arteriovenous anastomosis to treat resistant hypertension

Novel, interventional treatments have emerged in the last decade for the treatment of resistant hypertension. This review focuses on a unique device that creates a fixed calibre, central iliac arteriovenous anastomosis that is significantly different in haemodynamic and safety profile from traditional haemodialysis fistulae. The background, physiology, and clinical data to date will be presented.

The single, randomized, controlled clinical trial using the ROX coupler in patients with resistant hypertension demonstrated substantial reductions in both office and ambulatory blood pressure to 12-month postimplantation. There was a common, but manageable, adverse effect of upstream iliac venous stenosis causing ipsilateral lower limb oedema. There were no renal safety concerns. The mechanism of action is proposed to be mechanical by provision of a low-pressure parallel circuit attached to the high-pressure arterial system though detailed physiological evaluation is currently lacking.

Preliminary data using the ROX coupler to form a central arteriovenous anastomosis are very encouraging. Concerns regarding the lack of sham control are to some extent mitigated by immediate on table blood pressure reduction with opening of the coupler and will be further addressed in the ongoing pivotal, sham-controlled ROX CONTROL Hypertension2 study which should provide further robust information regarding efficacy and safety.