Surgical Technique Might Cure High Blood Pressure

A revolutionary new surgical system and procedure could reduce the risk of a major heart attack or stroke in those patients with persistent high blood pressure on whom medication has no effect.

The Symplicity Catheter System uses controlled, low-power radiofrequency (RF) energy to deactivate the renal nerves, thereby selectively reducing both the pathologic central sympathetic drive to the kidney, and the renal contribution to central sympathetic hyperactivity. The system has two main components, designed to work together as an integrated system to ensure consistent performance. The first is the Symplicity catheter, a low profile energy delivery catheter that delivers RF energy through the arterial wall to the renal nerves, which has an atraumatic, radiopaque, tip that minimizes risk of arterial injury and is easily visualized under fluoroscopy. The second component is the Symplicity generator, a fully automated, compact, RF generator with hands-free pedal activation and built-in control mechanisms and temperature and impedance monitoring functions to protect against excess energy delivery.

The surgical procedure, called renal sympathetic-nerve ablation, is a minimally invasive procedure that takes about 40 minutes, and patients recover quickly and can soon return to their daily lives. The Symplicity Catheter System is under development by Ardian (Palo Alto, CA, USA), and is undergoing clinical studies in patients with resistant hypertension and chronic kidney disease in centers across the United States, Europe, and Australia.

"This is the most exciting development in hypertension since the advent of antihypertensive medication 50 years ago. It is hard to forecast the limitations and it could eventually be compared to medication,” said Mel Lobo, M.D., a specialist in clinical hypertension with the United Kingdom National Health Service (NHS, London, United Kingdom).

The renal sympathetic nerves have been identified as a major contributor to the complex pathophysiology of hypertension, in both experimental models and in humans. Patients with essential hypertension generally have increased efferent sympathetic drive to the kidneys, as evidenced by elevated rates of renal norepinephrine spillover into the circulation. Hypertension is also characterized by an increased rate of sympathetic-nerve firing, possibly modulated by afferent signaling from renal sensory nerves.

Related Links:
Ardian
United Kingdom National Health Service