Midterm complications of ROX arteriovenous coupler device, managed by targeted endovascular repair: a case report

Resistant and uncontrolled hypertension prominently amplifies the risk of end-stage renal disease and fatal cardiovascular events. Therapeutic inertia, despite maximum tolerated anti-hypertensive medications, puts patients at high risk, thus non-pharmacologic therapies have been proposed. The ROX arteriovenous coupler (ROX, Medical Inc., San Clemente, CA, USA), initially developed for treatment of chronic obstructive pulmonary disease, exploits the biomechanical effects of diverting arterial blood into a low-resistance, high-compliance venous segment, thereby decreasing arterial vascular resistance and blood pressure (BP).

A 76-year-old male, non-smoker and non-diabetic with resistant primary hypertension presented to our institution with disabling claudication, lower limb swelling and right hip pain. He had concomitant saccular abdominal aortic and right iliac aneurysms. He had previously undergone renal denervation on two separate occasions yet continued to require increasing anti-hypertensive medications. He subsequently had an insertion of an ROX coupler device between his right external iliac artery and vein after failure of insertion into his left iliac system. He developed right hip and buttock pain and consequently underwent a total hip replacement and subsequent revision, which did not alleviate his symptoms. Ankle-brachial indices were reduced to 0.70 on the right limb and normal on the left. Insertion of the ROX coupler device was reversed with concomitant endovascular aortic repair.

There is no clear consensus on reversal of the ROX coupler device. Endovascular aortic repair reversal of the ROX coupler device in this case was safe, effective, and improved symptoms including patient's BP control and limb symptoms.