From Press Reports
The NMMC Heart Institute leads the state and nation again with new firsts:
Nation’s 1st bioresorbable heart device
Phyllis Camp of Saltillo has a new claim to fame-she has the nation’s first bioresorable heart device.
On Dec. 28, interventional cardiologist Barry Bertolet, M.D., and his team implanted the nation’s first bioresorbable vascular scaffold as part of a research study at North Mississippi Medical Center. Absorb, the world’s first drug-eluting BVS, works by restoring blood flow to the heart similar to a metal stent, but then dissolves into the body. The result is a treated vessel that may resume more natural function and movement because it is free of a permanent metal stent.
Camp, 61, of Saltillo suffered her first heart attack two years ago. “I have a strong family history of heart problems. My father had his first disabling heart attack at age 58, and I had mine at 59, she says. “I got two metal stents, and I recovered well and returned to work.”
But last year Camp began experiencing similar symptoms and failed an exercise stress test. She underwent a cardiac catheterization, which revealed a new blockage in an artery to her heart. That’s when Dr. Bertolet told her about the new dissolvable device.
Dr. Bertolet explained that the device is referred to as a scaffold because it is a temporary structure, unlike a stent, which is a permanent implant. The scaffold supports the vessel until the artery can stay open on its own, and then dissolves naturally.
“When the procedure was finished, Dr. Bertolet told me, ‘you’ve made history,’” Camp says. “I am awed and thankful to be involved in such an amazing groundbreaking event.” Shortly thereafter, her symptoms resolved and she returned to work as a dialysis social worker for Fresenius Medical Care.
“This technology represents a true shift in the way that doctors will treat patients with severe obstructive coronary artery disease,” Dr. Bertolet says. “We are excited about Absorb because it may allow blood vessels to return to a more natural state and expand long-term diagnostic and treatment options for cardiac patients.”
State’s 1st transapical tavr
On Nov. 27, NMMC became the first hospital in Mississippi to perform a transapical transcatheter aortic valve replacement (TA-TAVR). In this procedure, the valve is inserted through an incision between the patient’s ribs and through the bottom end of the heart called the apex.
Open heart surgery is usually done to repair or replace severely damaged heart valves, but unfortunately, not everyone is a surgical candidate. In February, NMMC became the first hospital in Mississippi to offer transfemoral TAVR, a promising new alternative for high-risk patients for whom heart surgery was not an option.
TAVR has been touted as a huge breakthrough for high-risk patients who suffer from aortic stenosis, meaning that their aortic valve-the door between the left ventricle and the heart’s main artery-is too narrow to open all the way. Left untreated, a person’s heart could get larger until it has trouble pumping. Fluid could build up in the lungs, and the heart could begin to fail. The heartbeat could become erratic, and the person could suffer a heart attack and die.
In the original transfemoral method, the valve was delivered through an incision in the leg. The new transapical method was approved by the U.S. Food and Drug Administration in late October for high-risk patients who don’t have suitable access through their leg artery. In these situations, the valve is delivered through an incision in the chest.
TAVR allows a team of doctors to replace a diseased valve without open heart surgery and without stopping the heart. TAVR is done by a cardiologist and cardiothoracic surgeon together in NMMC’s hybrid operating room, which is a cross between a cardiac catheterization laboratory and a surgery suite.
“Open surgery is still the treatment of choice for valve replacement,” says cardiothoracic surgeon David Talton, M.D, “but for high-risk patients-those who are older or have other serious health issues-TAVR is an excellent option to extend life.”
State’s 1st vagal nerve stimulator for heart failure
Doctors at NMMC have implanted the state’s first vagal nerve stimulator as part of a clinical research study to treat heart failure through nerve stimulation in the neck.
According to cardiac electrophysiologist Karl Crossen, M.D., and neurosurgeon Louis Rosa, M.D, research demonstrates a connection between the heart and brain that could benefit heart failure patients. Drs. Crossen and Rosa are leading NMMC’s participation in the INOVATE-HF clinical trial to determine if the CardioFit implantable electrical stimulation device improves heart function in congestive heart failure patients.
Since 1997, vagal nerve stimulation therapy has been used to control seizures in epilepsy patients; it has recently been approved for treating drug-resistant cases of clinical depression. This clinical trial is the first time it is being used to treat heart failure.
“In heart failure as the pump function weakens, the body attempts to adapt by using the adrenaline-or sympathetic-nervous system in the same way that when someone exercises the body uses adrenaline to increase heart rate and cardiac contraction,” Dr. Crossen explains.
“We now know that these adaptations over long periods of time are detrimental and that medications such as beta blockers, which block the adrenaline system, are associated with improved outcomes in heart failure. At the same time that the adrenaline system is ramping up to respond to worsening heart failure, the other counteracting system in our body, the ‘anti-adrenaline system,’ which is called the parasympathetic system, is suppressed in heart failure patients.
“There is no medication that predictably raises the ‘anti-adrenaline system’ back toward normal in a way that will offset this maladaptive effect. Stimulating the vagal nerve in the right side of the neck can directly raise the parasympathetic effect on the heart and is the basis for this treatment.”
Like a traditional pacemaker, the CardioFit device is implanted under the skin of the chest and attached to the heart-but it is also connected to a nerve in the neck. The device sends electrical pulses to the nerve, which sends signals to the heart.
Most patients are treated with prescription drugs that manage some symptoms, but these medications can’t stop deterioration caused by heart failure. The clinical trial will assess whether combining treatment with CardioFit and drug therapy is more effective than prescription drug therapy alone.
NMMC is one of only 22 sites in the United States and 36 sites worldwide participating in the INOVATE clinical trial. “Heart failure has a high mortality rate and significantly limits a patient’s ability to live a normal life,” Dr. Rosa says. “Our goal is to help the patient by providing increased heart function and improving quality of life.”
“We are very encouraged by the preliminary results,” Dr. Crossen adds.
State’s 1st triple-chamber pacemaker
In November, NMMC became one of the first eight hospitals nationwide chosen to implant the new Evia HF-T triple-chamber cardiac resynchronization therapy pacemaker.
The device puts out pulses to keep the heart beating regularly and on time, improving the health of patients with bradycardia and heart failure. Cardiac electrophysiologist Jim Stone, M.D., says the device’s most impressive feature is its wireless home monitoring technology that uses a cellular network at no cost to the patient. “The home monitoring system is completely automated and picks up information from the patient’s implanted device and transmits it to us daily,” he says.
Another benefit is the device’s TI feature, which measures thoracic impedance or lung fluid levels. Patients with heart failure are frequently hospitalized for fluid overload. “Usually the lungs are dry and full of air,” Dr. Stone says. “But when the lungs fill up with fluid, the electrical signal changes and the device alerts the physician. We can call the patient and check him and then adjust his medication. Being proactive can keep him from going into full-fledged heart failure.”
The new Evia HF-T pacemaker makes frequent automatic adjustments to optimize its own function. “This allows it to mimic normal rates and cardiac activation and improve heart failure,” Dr. Crossen explains. “It’s like having your car in the shop every day for a ‘tune-up,’ only it’s entirely automated and occurs without the patient even being aware.”
In addition to Drs. Stone and Crossen, cardiac electrophysiologist Keith Kyker, M.D., also implants the new pacemaker at NMMC.