Good news for the millions suffering from treatment-resistant hypertension. Medtronic's ($MDT) Symplicity renal denervation system helped reduce blood pressure for up to three years in patients who completed a follow-up of a clinical trial, according to data presented at the 2012 American College of Cardiology meeting.
The Symplicity HTN-1 study included 153 patients in Australia, Europe and the U.S., and investigators saw positive results. At 6 months 71% of patients were classified as responders. That number increased to 100% among those who completed three-year follow-up.
But what is really intriguing, as Heartwire notes, is initial nonresponders demonstrated a reduction in blood pressure months after the intervention. "Nobody understands why, but it's definitely a huge novel finding in terms of better understanding what this whole thing is doing," program cochairman George Bakris told Heartwire. "We are learning as we go."
Results showed 58% of trial subjects responded three months after the procedure, 64% by one year, 82% by two years and 100% after three years, the news service reports.
In a separate study, 106 randomized patients were also evaluated. Results showed that 47 patients sustained their significant drop in blood pressure at a 12-month follow-up. Furthermore, they showed a significant difference from the previously reported 6-month follow-up.
The Symplicity system includes a flexible catheter and generator. A doctor inserts the catheter through the femoral artery in the upper thigh and threads it into the renal artery. Once the tip is in place, the generator then delivers a controlled, low-power radio-frequency energy routine to deactivate the surrounding renal nerves.
Doctors have used the Symplicity system to treat more than 4,000 patients since 2007. It is available in parts of Europe, Asia, Africa, Australia and the Americas. However, the FDA has not yet given its blessing to the system.
As the company notes in a release, treatment-resistant hypertension affects roughly 120 million people worldwide, putting them at risk for kidney disease, stroke, heart attack and heart failure.
- check out the Medtronic release
- read the Heartwire coverage (subscription required)