This study compares two ways to fix a heart valve problem called "degenerative mitral valve disease." The mitral valve is part of the heart that helps blood flow the right way. Some people in the study will get a new device called the Neochord DS1000 System to fix their valve, while others will have traditional open-heart surgery. Open-heart surgery uses a heart-lung machine, called cardiopulmonary bypass, to keep blood pumping while the heart is fixed. The study wants to see if the new device is safe and works well.

• Study length is not specified, but participants will need regular follow-ups.
• Participants must have a specific heart valve issue and cannot have had certain other heart surgeries.
• Participants should consider if they are comfortable with either a new device or traditional surgery.

To join, you must need this type of heart repair and have certain heart conditions. You cannot join if you've had this surgery before or have had other heart surgeries recently. This study is important to find easier ways to fix heart valves.