Could blood pressure be better controlled with new FDA-approved treatment? What to know.

When you think high blood pressure, you probably think heart, but maybe you also should think kidney.

A new FDA-approved treatment for high blood pressure targeting the nerves of the kidneys has been studied in Austin and is now being done at the Heart Hospital of Austin. On March 27, the hospital became the first in Central Texas to do a renal denervation outside of a study.

"The kidney is a major player in blood pressure," said Dr. Frank Zidar, an interventional cardiologist at the hospital who performed the procedure. The blood vessels in the kidneys control how much salt and water is in the body. When the body retains water and salt, the blood pressure rises. That is why, often, people will take two types of medications to control their blood pressure: an alpha blocker or beta blocker that regulates the blood vessels around the body, and a diuretic that helps the kidneys remove water.

What is a renal denervation?

During the renal denervation, Zidar places a specialized catheter into the groin to reach the nerves of the kidneys. He watches the kidney nerves in real time using an X-ray table. Then with radio frequency, Zidar ablates (or burns) renal nerves that are between 3 to 8 millimeters to make them no longer reactive, preventing them from telling the kidney to hold onto water and salt to make the blood pressure rise.

Because there are many tiny nerves to the kidney, Zidar won't hit all of them, but he will be able to hit the major nerve trunk and the larger branches.

This ablation is not unlike ablating a heart that has an area that is causing an abnormal rhythm, or an area of the brain that is causing seizures.

After 20 minutes, the procedure is done. Typically, people only experience some pain at the site where the catheter went in. Currently, that's in an artery in the groin, but as this procedure becomes more common, Zidar says, he will eventually go into the body through an artery in the wrist.

What are the results of a renal denervation?

Wanda Brown, 88, was the first patient to have a renal denervation at the Heart Hospital of Austin outside of a study. "It was a piece of cake," she said.

During the clinical study, renal denervation caused less fluctuation in the blood pressure, and the top number (systolic) dropped on average by seven, the bottom number (diastolic) by two. That would mean someone having a high blood pressure of 147/90, would see a drop to 140/88. Normal is near 120/80, and while the person's blood pressure still might not be normal, the procedure has reduced the blood pressure, putting less strain on the heart and other organs.

While that might seem like a small change, "the reduction is notable," Zidar said.

Why does a small lowering of blood pressure matter?

The danger of high blood pressure is that it sneaks up on you, Zidar said. You might not feel bad, but eventually it will wear you down. Think about lowering your blood pressure "like saving a dollar a day. You will reap the benefit," he said.

For Brown, she no longer has huge fluctuations in her blood pressure. She had high blood pressure for more than 30 years and used multiple medications, tried to stay active and eat well. "They would try things, and it would have no effect at all," she said. "That's just been difficult."

She discovered her heart is not the problem, Brown said. "In fact, for someone my age, it is in pretty good shape," she said.

After the denervation, her top numbers went from the 140s and 150s to upper 120s to 130s. "That's substantial," Brown said.

Now she and her doctors are working out whether she'll need less blood pressure medication because of her lowered numbers.

More studies will need to be done on whether doing the renal denervation could be cost effective because of more blood pressure control and fewer medications, Zidar said. Because it is FDA approved, insurance does cover the cost of the treatment. Costs will vary based on insurance. Medicare reimburses $5,432 for the procedure.

This article originally appeared on Austin American-Statesman: Austin hospital uses new FDA-approved procedure to help blood pressure