New Melody Transcatheter Pulmonary valve helps congenital heart defect patients avoid multiple surgeries

May 13 2010

Congenital heart defects are the most common type of major birth defect in the U.S., affecting about 25,000 babies each year. Now, a new valve being used at the University of Michigan's C.S. Mott Children's Hospital Congenital Heart Center can help patients delay or avoid multiple surgeries.

A small number of these infants are born with defects of their pulmonary valve, which is responsible for regulating the flow of blood into the lungs.

These patients may require surgery to have a conduit or tube replace the pulmonary valve, and multiple open-heart surgeries are needed to replace it over time, as the body outgrows it.

The new Melody Transcatheter Pulmonary valve is introduced into the heart through a catheter inserted into a vein in the patient's leg during a heart catheterization. This procedure could revolutionize care for these patients -- saving them from multiple open-heart surgeries and helping them lead a better quality of life.

The valve has been used in Europe since 2000 and was approved by the FDA for use in the United States in January, 2010. Mott Children's Hospital's Congenital Heart Center is the first hospital in the state, and one of the first in the country, to receive approval by Medtronic to use the valve in patients.

"There can be very severe problems with the pulmonary valve - it may be essentially non-existent when a child is born," says Aimee Armstrong, M.D., Assistant Professor in the Department of Pediatrics & Communicable Diseases at the University of Michigan. "These children need to have a conduit or tube placed from the right ventricle to the pulmonary arteries to allow blood flow into the lungs."

"These conduits do not grow with the patients. Some conduits only last a year or two and others can last more than a decade," she adds. "Patients with conduits need to have multiple open-heart surgeries to get new conduits when they become narrowed or leaky."

Avoiding open-heart surgery is key to improving the quality of life of any patient with a congenital heart defect, she adds.

"Every time you do an open-heart surgery, more and more scar tissue develops. So the next time the surgeon has to go in to do the surgery, it's riskier because there's so much scar tissue and it makes the surgery longer and more difficult."

The Melody valve is a breakthrough innovation that allows interventional cardiologists to implant a heart valve through a small catheter that's entered through the vein in the leg, advanced up into the heart and deployed.

"Patients do not need stitches," Armstrong says. "The incision is very small. They go home the next day and can go back to work or school in a few days."

The Melody valve is a tissue valve that's sewn inside of a wire stent and crimped onto an angioplasty balloon on the end of a catheter. The balloon is inflated and that deploys the valve.

The valve's purpose is to delay the time until patients need surgery and hopefully that will decrease the number of open-heart surgeries they need over a lifetime.

"This is a huge breakthrough," says Armstrong. "There's a lot of pain, morbidity, and time off of work and school that is involved with open-heart surgery, and patients want to do everything they possibly can to avoid that."

Melody implants have been very successful in Europe, where most of the procedures have occurred until now. The procedural success is over 95 percent and the vast majority of patients have minimal leakage and very minimal narrowing after the valve is placed, Armstrong added.

The FDA has required a post-approval study, and 10 centers in the United States have been chosen to participate in that study, including the University of Michigan.

"The Michigan Congenital Heart Center was chosen because of our large surgical volume," Armstrong says. "We have the second largest pediatric cardiac surgical volume in the country, and we're consistently ranked in the top 4 among pediatric cardiac programs in the U.S."

Lisa Snider, a 27-year-old congenital heart patient from Grand Rapids, was one of the first patients to have a transcatheter valve replacement at Mott.

"I was born with tetralogy of fallot and that is a condition where you're born
with a hole in your heart and the pulmonary valve is faulty; it did not work pumping the blood," Snider says.

Snider has had 2 cardiac surgeries, one at 6 days of age and the other at 4 years.

Last year, doctors advised that she have a Melody implantation, particularly if she and her husband were planning to have children.

"Yesterday at 6 p.m., they began the valve replacement. It was a 4 or 5 hour procedure and I was to stay in ICU for 24 hours," Snider says. "But it's like 12 hours later or 18 and I'm up and getting ready to go."

"I feel great," she says. "Just a little hungry."

SOURCE University of Michigan