Written by Kim O’Brien Root
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Sentara will participate in worldwide clinical study examining the connection between the heart and brain
[dropcap]It’s a tiny device, about the size of a 9-volt battery, and sits under the skin just below Barbara Pope’s collarbone.[/dropcap]It’s been there since the end of November, delivering electrical signals to a nerve in the 47-year-old’s neck. If she pokes at it, she can feel it, but otherwise she can’t tell it’s there. Soon, however, she hopes its presence will bring back some of the energy she lost when diagnosed with congestive heart failure two years ago.
Doctors and researchers, too, are hoping the device will mitigate the effects of heart failure—not just for Pope, but for people worldwide who suffer from the debilitating condition.
The Newport News resident is one of about 650 people in the United States and Europe expected to take part in a clinical study called INOVATE-HF, which focuses on the connection between the heart and brain. The study is being done at the Sentara Cardiovascular Research Institute—one of about 80 medical institutions taking part and the only one in Virginia.
“This,” says Dr. John Herre, a cardiologist and the scientific director for the Sentara institute, “is a novel approach.”
The research institute, established in 2005 and based in Norfolk, is involved in about 70 ongoing studies each year and is considered one of the top cardiac research programs in the country.
Last fall, the institute began looking for people for the INOVATE-HF study, hoping to try out what’s being touted by the device’s developer—BioControl Medical—as a new approach to treating heart failure. A smaller pilot study conducted in Italy, Germany, the Netherlands and Serbia has already had promising results, which were published in April 2011 in the European Heart Journal.
More than six million adults in the U.S. suffer from congestive heart failure, a condition in which the heart can’t pump enough blood and oxygen to support other organs in the body. Those affected struggle with shortness of breath, trouble breathing and general fatigue.
Heart failure is the primary cause of more than 55,000 deaths each year, with about half of those diagnosed dying within five years of the diagnosis, according to the Centers for Disease Control.
While there is no cure for heart failure, it can be treated with medicine and lifestyle changes. Doctors typically start treatment with beta blockers, a class of drugs that prevents the stimulation of receptors in the body’s nervous system that are responsible for increased cardiac activity.
Doctors are largely successful in using the beta blockers to suppress the sympathetic nervous system—the branch that when activated, is like giving a person adrenaline, Herre said. Adrenaline isn’t good for the heart.
[quote]Heart failure is the primary cause of more than 55,000 deaths each year, with about half of those diagnosed dying within five years of the diagnosis, according to the Centers for Disease Control.[/quote]But there’s another branch of the nervous system—the parasympathetic, which has a calming effect on the heart through signals carried from the brain to the heart. In a healthy person, the two branches are in synch, the connection between the heart and brain in balance.
“If you believe in evolution, we evolved to survive having our arm ripped off by an animal,” Herre says. “That’s how we’re put together. Your sympathetic nervous system is active, the parasympathetic is suppressed. You secrete adrenaline, and the heart redirects blood where it needs to go.”
The body interprets heart failure the same way, he says—the sympathetic branch works harder, while the parasympathetic slows down. But that causes the two branches to become out of balance.
In the case of heart failure, it’s better to suppress the sympathetic and activate the parasympathetic, Herre says. Fortunately, medications are good at working on the sympathetic—blocking that release of adrenaline. But current medical therapy only addresses half the problem—there’s nothing available to stimulate the parasympathetic side.
That’s where the INOVATE-HF device comes in.
Leads connected to the device, which looks similar to a pacemaker, are threaded into the neck to the vagus nerve and to a lower chamber of the heart, in order to sense the heart’s activity. Electrical signals are sent through the lead to stimulate the nerve, and therefore the parasympathetic nervous system.
Researchers have known for a while that stimulating the vagus nerve could help, Herre says, but getting to this point took a better understanding of the mechanisms of heart failure as well as a better understanding of the technology needed. The technology behind the INOVATE-HF device, called the CardioFit system, is “pretty remarkable,” Herre says.
“This method to stimulate looks very promising,” says Herre, who has participated in more than 40 clinical trials, including a landmark study that helped bring an implantable defibrillator into wider use. “There are no big studies that show it works, but nothing shows it doesn’t work. We think it’s going to work. We think it’s going to work for a long time.”
Pope hopes so.
She was the first to join the Sentara study after traditional medications used to treat her congestive heart failure didn’t work. When she became ill in 2011, doctors initially thought she had pneumonia. She was tired, short of breath and couldn’t keep food in her stomach.
By the time Pope saw a cardiologist at Sentara, she couldn’t walk from her bedroom to the bathroom without getting winded. She had to sleep propped up with four pillows so she could breathe. She couldn’t play with her grandchildren because she was just too tired.
The diagnosis of heart failure stunned her. “I was in shock, because I had never been sick,” she says.
Medication has helped some—Pope says her shortness of breath isn’t quite as bad as it was. But doctors thought she’d be a good candidate for the study. Her heart failure is considered Class 3—patients in this class are usually comfortable at rest, but get short of breath with normal activity.
While in the study, a patient remains on their current heart medications that block the sympathetic nervous system. The INOVATE-HF is periodically adjusted to find the correct stimulation of the nerve.
Pope hasn’t noticed any difference just yet, but Herre says it can take months to see results. The study isn’t expected to be completed until 2015, but Herre says if it works very well, it could stop early. It’s considered a pivotal trial, the last study that will decide whether the device is approved.
Researchers hope the device accomplishes several things, including improving a patient’s quality of life by getting her to walk without getting out of breath. Shrinking the heart is another—with heart failure, the heart tries to compensate by getting bigger, which puts more stress on it and worsens it over time.
The European study showed that the hearts of the people who got the INOVATE-HF device did, in fact, get smaller, Herre said. There was also improvement in the patients’ injection fractions—a measurement that determines how well the heart pumps out blood.
“If we make the heart function better, we can make the heart shrink down,” Herre says. “That’s correlated with living longer and feeling better.”
A major goal of the study is also to keep people out of hospitals, Herre says. According to the CDC, heart failure costs the nation more than $34 billion each year, including the cost of health care, medication and lost work productivity.
Pope says she hopes her participation in the study will lead to not only improving her own health, but also others with heart failure. Her personal goals are simple: She wants to take a long walk. She wants to take her seven grandchildren to the park, to go outside and run behind them. She doesn’t want to have to explain any longer why she can’t.
“They ask me why I’m sick and why I go back and forth to the hospital,” Pope says. “I just tell them Grandma’s sick, but when she gets better she’ll do the same things she used to do with them.”