The US Food and Drug Administration (FDA) has granted approval to the world’s first non-surgical pulmonary valve to treat severe pulmonary valve regurgitation, a condition often resulting from congenital heart disease. The device, developed by world-leading medical technology company Medtronic, is indicated for both pediatric and adult patients who have severe pulmonary valve regurgitation. The condition causes blood to leak backward into the right lower chamber of the heart.
The pulmonary valve is called the Harmony Transcatheter Pulmonary Valve (TPV) System and is designed to improve blood flow to the lungs in patients with severe pulmonary valve regurgitation without requiring open-heart surgery.
Currently, the standard treatment for severe pulmonary valve regurgitation is open-heart surgery to remove the diseased valve and replace it with a new one. The new Harmony pulmonary valve is designed so that it can be implanted non-invasively and non-surgically through a catheter inserted in a vein in the groin or neck.
Medtronic’s pulmonary valve can be used to treat patients with a native or surgically-repaired right ventricular outflow tract (RVOT), which is the part of the heart that carries blood out of the right ventricle to the lungs. The Harmony pulmonary heart valve may delay the time before a patient needs additional open-heart surgery, and may also reduce the total number of surgeries a patient may need over their lifetime.
Many patients with severe pulmonary valve regurgitation may receive a tube implant early in life to correct disruptions in the outflow tract; however, over time, they can outgrow the conduit or it may no longer be functional.
“The Harmony TPV provides a new treatment option for adult and pediatric patients with certain types of congenital heart disease. It offers a less-invasive treatment alternative to open-heart surgery to patients with a leaky native or surgically-repaired RVOT and may help patients improve their quality of life and return to their normal activities more quickly, thus fulfilling an unmet clinical need of many patients with congenital heart disease,” said Bram Zuckerman, MD, director of the Office of Cardiovascular Devices in the FDA’s Center for Devices and Radiological Health in a press announcement from the agency.
The Harmony pulmonary valve is implanted using a thin catheter with a collapsed Harmony valve on the end. The catheter carrying the valve is inserted through a vein in the groin or in the neck into the right side of the heart and into the RVOT where it is placed into position. The valve is then released from the catheter and expands on its own, anchoring to the RVOT. Once the new valve is in place, it opens and closes like a door to force the blood to flow in the correct direction.
Congenital heart defects (CHDs) affect approximately 40,000 babies each year and are the most common type of birth defect. In the US, it is estimated that over two million infants, children, adolescents and adults are living with CHDs. The conditions present at birth and can affect the structure and function of the heart.
Patients with CHDs often require heart procedures early in life to help improve blood flow to the lungs. In some cases, the procedures may leave patients without a working pulmonary valve, which could lead to pulmonary regurgitation. Severe pulmonary valve regurgitation may be corrected by implanting a right ventricle-pulmonary artery conduit or an artificial valve through open-heart surgery.
FDA Assessment of the Harmony Pulmonary Valve
The safety and efficacy of the Harmony pulmonary valve were assessed by the FDA through a prospective, non-randomized, multi-center clinical study. In the study, the device was implanted in a total of 70 patients with severe pulmonary valve regurgitation. All of the patients were scheduled for follow-up examinations at the start of the study, at implant procedure, discharge, and post-implant at one month, six months and annually for five years after the procedure. As part of the post-approval study, the follow-up has now been extended to ten years.
The primary safety endpoint in the study was no procedure- or device-related death within 30 days following the implant. One hundred percent of the patients achieved this endpoint. The primary effectiveness endpoint was percentage of patients with no additional surgical or interventional procedures related to the device and acceptable heart blood flow function at six months. Of the patients with severe pulmonary valve regurgitation who received the Harmony pulmonary valve, 89.2 percent achieved the primary effectiveness endpoint, not requiring further any interventions at the six-month mark.
Adverse events observed during the clinical study included irregular or abnormal heart rhythms, leakage around the valve, minor bleeding, narrowing of the pulmonary valve, and movement of the implant.
The Harmony transcatheter pulmonary valve was granted Breakthrough Device Designation for the treatment of pediatric and adult patients with severe pulmonary valve regurgitation. The program allows for the expedited development and review of devices that may offer more effective treatment or diagnosis of life-threatening or irreversibly debilitating diseases or conditions.
It was approved under the Premarket Approval (PMA) pathway, which is the most stringent type of device marketing application required by the FDA. It is based on the FDA’s determination that the PMA application contains sufficient valid scientific evidence to provide reasonable assurance that the device is safe and effective for its intended use(s).
The Harmony pulmonary valve builds on Medtronic’s previous Melody transcatheter implant, which completely replaces the pulmonary valve in patients with severe pulmonary valve regurgitation. The Melody valve is designed to be a longer-lasting valve to help delay additional surgeries. The device received an FDA humanitarian device exemption in 2015, and last year, Medtronic presented long-term data showing that it sustained function and stability, with 97 percent of patients showing mild, trace or no regurgitation after ten years, and 61 percent of patients not requiring additional procedures including catheter-based reintervention.
It will be important to see how Medtronic’s new Harmony pulmonary valve performs long-term. Nevertheless, a non-surgical option for severe pulmonary valve regurgitation is a welcome first in the congenital heart disease space.