Repairing the mitral valve: with surgery or with a catheter? (PRIMARY study)

Mitral valve insufficiency is the second most common acquired heart valve disease. Around one million people in Germany are affected. Blood passes through the mitral valve from the left atrium into the left ventricle and is pumped from there into the body. If the valve is leaky, blood flows back into the atrium and accumulates in the lungs. A typical symptom of mitral valve insufficiency is therefore shortness of breath. 

For many years, the standard procedure has been to repair the mitral valve using keyhole surgery. In this procedure, endoscopically, the diseased chordae tendineae are replaced and the valve ring is stabilized with an implant. This method is often used for mitral valve prolapse. This occurs when the “suspension” of the valve, i.e. a chordae tendineae, is torn or worn out. The upper part of the valve then flaps into the atrium with every heartbeat.

In addition, a catheter-based procedure has also become established in the last ten years. In this procedure, one or more clips are pushed through the groin to the left heart, with which the opposite parts of the two mitral valve leaflets are gathered together so that the valve closes again. The procedure is often used when the valve is still healthy but no longer closes properly because the heart chamber has expanded due to heart failure.

Both procedures possible – but limited data available

Patients with very high surgical risk are also treated with the clip procedure for mitral valve prolapse. The procedure is therefore also suitable for some forms of this type of valve damage. “In people with mitral valve prolapse and a lower surgical risk, we can use both methods under certain conditions. However, the data on which procedure patients benefit most from in the long term is very limited,” says Prof. Volkmar Falk from the German Heart Center at the Charité. He is leading the German arm of the US-American PRIMARY study. 

The study includes patients aged 60 and older with severe mitral regurgitation due to mitral valve prolapse. Patients are randomly assigned to two groups. Half receive surgical repair, usually endoscopic, while the other half are treated with a catheter-based procedure.

Long-term data is collected

Three years after treatment, the study team checks whether the patients are alive and well or need to be readmitted to hospital due to their mitral valve or heart failure. Of course, the outcome of the repair is also checked. “We also have the unique opportunity here to track which method is better in the long term. That's why we continue to monitor the patients for up to 10 years after treatment,” says Falk. 
 

In addition to the DHZC, 16 other German centers will participate in the study.

Study title: Percutaneous or Surgical Repair In Mitral Prolapse And Regurgitation for >60 Year-olds PRIMARY, clinicaltrials.gov

Principal Investigator: Prof. Dr. med. Volkmar Falk, Medical Director of the German Heart Institute Berlin, Director of the Clinic for Cardiovascular and Thoracic Surgery, volkmar.falk@dhzc-charite.de

Press contact: Christine Vollgraf, Press and Public Relations, German Center for Cardiovascular Research (DZHK), Tel.: 030 3465 529 02, presse(at)dzhk.de.

The press release was updated on January 31, 2024.