Conduits are surgically implanted valves used to treat congenital heart defects of the pulmonary valve. Patients with congenital heart defects have narrowed, leaky, or missing pulmonary valves that impede the proper flow of blood from the heart’s right ventricle to the pulmonary artery, which then sends the blood on to the lungs for oxygenation. Conduits can have a limited lifespan and often require replacement. The Melody is intended to provide another option to conduit replacement.
“The FDA’s approval of Melody allows patients to undergo a much less invasive procedure to treat their heart condition,” said Jeffrey Shuren, J.D., M.D., director of the FDA’s Center for Devices and Radiological Health. “Congenital heart defects represent the number one birth defect worldwide and this approval represents a new, first-of-a-kind treatment option for some of those patients.”
Like other valves, the Melody does not cure the heart condition and over time, the Melody may wear and require replacement. However, it is implanted without open heart surgery, can prop open the poorly functioning conduit, and can keep blood flowing in the proper direction because of the tissue valve in the Melody. These characteristics will allow a patient’s conduit to function longer than usual, which can delay the need for more invasive open-heart surgery.
Approval of the Melody valve should be especially beneficial to pediatric patients with right-sided valvular heart disease who may face several surgeries over their lifetimes.
Clinical studies of 99 participants in the United States and 68 participants in Europe showed that the device improved function of the heart, and the majority of participants have noted improvements in their clinical symptoms. The device showed similar, limited durability compared with existing alternative treatments; 21 percent of U.S. participants experienced a stent fracture, a rate consistent with stent fractures reported for the bare metal stents presently used to treat congenital heart defects of the pulmonary valve.
As a condition of the FDA’s approval, the system’s manufacturer, Medtronic Inc. of Minneapolis, will conduct two post-approval studies to assess long-term risks and benefits as well as to evaluate the physician specialization needed to perform the implantation procedure, also called generalizability. One study will continue to follow 150 participants from the initial clinical trial for five years, and the second study will enroll more than 100 new participants to be evaluated over five years, in order to evaluate and assess the training program. Safety and benefit assessments will be part of both studies. The FDA also requires that Medtronic maintain a database of Melody recipients.
The FDA approved the Melody under the Humanitarian Device Exemption (HDE) program, which supports the development of medical devices intended to benefit patients in the treatment or diagnosis of diseases or conditions affecting fewer than 4,000 people in the United States per year. Under an HDE, the FDA can approve a device for limited use if there is a reasonable assurance that the device is safe and if the probable benefit to health outweighs the risk of injury or illness. Such products can only be used at medical institutions with an overseeing Institutional Review Board.
Manufacturers of most HDE devices are prohibited from selling their device for an amount that exceeds the costs of research and development, fabrication and distribution of the device. However, this prohibition does not apply to an agency-specified number of Melody devices sold each year and intended for the treatment or diagnosis of a disease or condition that occurs in pediatric patients, due to a provision in the Pediatric medical Device Safety and Improvement Act of 2007.