Healthy New Albany Magazine
By Stephan Reed
A New Albany doctor is at the forefront of a new technique to help those who suffer from high blood pressure.
Dr. Mitchell Silver, interventional cardiologist at OhioHealth Riverside Methodist Hospital, is using renal denervation therapy to improve resistant hypertension.
“There is a technology available for these people that addresses the problem and decreases their blood pressure if medication isn’t working,” says Silver, who also leads the hospital’s hypertension clinic.
The clinical trial, called Symplicity, calls for surgeons to implant a medical device that disrupts hyperactive nerves with a brief radio frequency.
Access to the renal artery is fairly simple, which may be how the procedure received its name, Silver says.
“Using conventional catheters, we are able to access the renal artery through the groin,” he says. “This is where sympathetic nerves cluster, which directs sympathetic activity and essentially drives blood pressure. The device is removed after the treatment.”
The treatments operate on the theory that the kidneys communicate with the brain to regulate blood pressure. People with hypertension have hyperactive renal nerves that raise blood pressure. The trial has been conducted as a part of clinical research and has not been approved by the Food and Drug Administration, but it has proven effective for Jill Smith, who went through with the procedure in 2012.
“I was taking so many different pills and diuretics; anything that may work,” she says. “One day, my doctor saw this study come across his desk and said immediately that it was for me.”
To qualify for renal denervation therapy, a patient must suffer from resistant hypertension.
“They must be on three blood pressure medications,” Silver says. “One medication has to be a diuretic and, despite that, their systolic blood pressure number (must have been) still above 160.”
The systolic number represents the amount of pressure the blood exerts on arteries each time the heart beats. As the top, or systolic, number rises, more damage is done to the vessels and arteries.
The OhioHealth trial Symplicity 3, which targeted people with very high blood pressure, is closed, but a new trial opens shortly under the name Symplicity 4.
“This time, we will target patients with a systolic blood pressure reading of 140 and above,” Silver says. “The trial will be a bit more liberal with who is involved.”
A systolic number of 160 or above represents Stage 2 Hypertension and should be treated immediately. A healthy person has a systolic number of 120 or below.
After being diagnosed with resistant hypertension, the patient had to undergo a four-week process of screenings and blood pressure diaries, along with a normal medication cycle, to qualify. If the condition continues after this process, the patient is subject to a renal catheter and an injection of dye in preparation.
About 10 percent of people with high blood pressure have resistant hypertension – and with it, an increased chance of heart disease, Silver says.
“We know from history that this group of people has a threefold increased risk of heart attack and stroke,” he says. “They are at a very high risk and should know their target blood pressure level.”
Some patients who suffer from resistant hypertension also experience limited mobility and activity.
“I couldn’t exercise before because my blood pressure would get too high,” Smith says. “I knew something had to be done.”
European countries and Australia have already approved the therapy and have found it beneficial, Silver says.
“These other countries have performed three clinical studies and the average patient saw a 30-point drop in blood pressure,” he says. “About 600 patients have gone through it in total.”
The procedure is irreversible and has a low risk of problems after surgery.
“There is, of course, a little bleeding because of the nature of the surgery,” Silver says. “There is also a theoretical risk of damaging the renal artery. That has been looked at, and after six months, there has been no damage done whatsoever.”
Renal denervation therapy is responsible for helping patients such as Smith get healthy once again.
“It doesn’t completely cure the problem, but it lowered my blood pressure to the point where I could take back control,” Smith says. “I can exercise now. I can do it on my own.”
Smith’s participation in the trial is only one patient’s experience, but she commends the therapy for what it has done for her.
“The doctors at OhioHealth were so comforting and helpful throughout the whole trial,” she says. “I highly recommend this for anyone going through what I went through. You will not regret it.”