COAPT Clinical Trial for Mitral Valve Regurgitation

New "Clip" Options for Patients with Mitral Valve Regurgitation

Until recently, high-risk heart patients with a severe form of leaky mitral valve disorder called mitral regurgitation (MR) had few treatment choices. Now, as part of the continuing evolution of cardiac disease treatments, the University of Maryland Comprehensive Heart and Vascular Center offers these patients a minimally invasive, catheter-based procedure that uses a clip to repair the leakage.

The Heart and Vascular Center's clip procedure is aimed at two types of MR patients. One group, with degenerative MR — too sick to undergo conventional heart surgery because of severe mitral valve structural defects — can undergo a procedure to receive a clip that has been approved by the United States Food and Drug Administration. The second group of patients may be eligible to participate in a clinical trial, called COAPT, evaluating the clip in patients with functional MR. These are patients whose valve structure is normal, but whose MR is related to an enlarged heart and heart failure.

The team prefers to take a minimally invasive approach to valve repair for all high risk patients because patients typically recover more quickly than open surgery and have fewer complications. The implantation of this clip goes a step further since it is considered a non-surgical intervention.

Early Results

The team has treated patients with MitraClip® TMVr since 2014, following FDA approval for primary, degenerative mitral regurgitation and through the COAPT trial for secondary, functional mitral regurgitation.

Recent results in this COAPT trial may redefine the care of advanced heart failure patients. The study revealed a significant and dramatic reduction in hospitalization and mortality for heart failure patients on optimal medical therapy and at least moderate to severe secondary, functional mitral regurgitation who received transcatheter mitral valve repair (TMVr) using MitraClip®. Hospitalizations for heart failure decreased from 67.9 percent to 35.8 percent per year, and 24-month mortality rates were reduced by 50 percent – 46.1 percent in the control group compared to 29.1 percent in the MitraClip group (Stone G.W., et al. NEJM. 2018 Sep). Importantly, the MitraClip® procedure was very safe in this high risk population, with a 96.6 percent freedom from device related complications at twelve months.

As FDA approval for secondary, functional mitral regurgitation is pending, we remain the only hospital in the State of Maryland able to treat these patients through the ongoing COAPT Continue Access Study. This trial runs until 2024.

How the Clip Works

The clip is delivered to the mitral valve by a catheter, passed through a vein in the groin, which travels up into the heart. The device, a clip with two arms, is positioned between the mitral valve's two leaflets. The arms are closed to pull the leaflets together and permanently lock them in place. This procedure is performed by a multidisciplinary team of physicians and nurses that includes a cardiac surgeon, interventional cardiologist and specialists in echocardiography and cardiac anesthesiology. Heart failure specialists evaluate and manage the care of the patients prior to and following the procedure.

In MR, the leaflets of the valve do not close properly, allowing blood to backflow, or regurgitate, from the left ventricle back to the left atrium. Since some of the blood leaks backward, the heart has to pump more blood with each beat to push the same amount of blood forward. Symptoms may include shortness of breath, fluid retention, fatigue and lightheadedness. Untreated MR can lead to heart failure and irregular heartbeat, worsening the heart's ability to pump blood to meet the body's needs.

What to Expect at the First Appointment

When patients come to the doctor's office, they are seen by a multidisciplinary team of specialists, including:

• Interventional cardiologist
• Cardiac surgeon
• Cardiologist specializing in heart failure

This first appointment can take anywhere from four to eight hours to ensure all appropriate testing is completed. Patients should bring reading materials and a caregiver, if possible, to help take notes and ask questions as an extra listener.

After the patient is seen by the specialists and gets the opportunity to ask any questions about treatment options, the clinical team discusses the best care plan for each patient based on their specific health needs and medical background.

COAPT Trial

Patients enrolled in the COAPT trial are those who have advanced heart failure and have been deemed "inoperable" by the cardiac surgeon, meaning traditional mitral valve surgery is not an option.

Patients in the COAPT trial will be randomized to two groups. The device group will be treated with the clip and the current standard of care. The control group will continue to receive the standard of care, which may include medications, implantation of a pacemaker to help the heart beat normally and treatments for coronary artery disease. Study participants will be followed for five years to see if admissions to the hospital for heart failure are reduced with the clip therapy, as has been seen in treated patients with degenerative MR.

Patient Eligibility for COAPT

The COAPT study is limited to a very specific group of patients, says co-principal investigator Mark R. Vesely, MD, assistant professor of medicine at the University of Maryland School of Medicine and interventional cardiologist at the University of Maryland Comprehensive Heart and Vascular Center. "This approach is for patients with moderate-to-severe or severe functional mitral regurgitation," says Dr. Vesely. "Further, it is aimed at patients who may not survive standard mitral valve surgery either because they are too frail or have other risk factors. Beyond medications and devices such as pacemakers, this group of patients has had few options to pursue."

Click here to view eligibility criteria on clinicaltrials.gov.

After the Clip Procedure

Patients who receive a clip for mitral valve regurgitation have an average hospital stay of two to three days after surgery.

One week after being discharged from the hospital, patients will receive a phone call from the clinical team to discuss their recovery and address any questions the patient or caregiver may have.

Follow-up appointments are required at three months after the operation, six months and one year. A standard echocardiogram is typically performed at every visit to view the function of the heart.

About Mitral Valve Regurgitation

Mitral valve regurgitation is the most common type of heart valve disorder, with the risk for the disorder increasing with age. One U.S. study found mitral valve disease in over nine percent of people in their 70s. MR may occur suddenly, when a heart attack damages muscles around the mitral valve, or the cords that attach the muscle to the valve break. An infection that destroys part of the valve can also bring on regurgitation. Often, there are no symptoms. When symptoms occur, they may develop gradually.

For more information about treatments for mitral valve regurgitation, contact Amy Krebs at akrebs@medicine.umaryland.edu or call 410-32-VALVE (410-328-2538).