Mitral valve regurgitation is one of the most common heart valve disorders and mitral valve repair is the favored therapy. For preoperative planning of the procedure, heart surgeons mentally interpret ultrasound images of the mitral valve. To improve preoperative understanding of the mitral valve and preoperative planning of the repair, we and other groups research patient-specific mitral valve replicas. The mitral valve is segmented from 3D ultrasound image data of the heart and a corresponding casting mold is designed and 3D printed. With it, the mitral valve replica is cast out of silicone. So far, segmentation and casting mold design are done manually. This makes the manufacturing of the mitral valve replicas laborious and complicates clinical application. We present patient-specific mitral valve replicas where the segmentation is semi-automatic and the casting mold design is completely automatic. We use an existing software that semi-automatically segments mitral valves from 3D ultrasound image data and developed an automatic casting mold design that automatically creates casting molds based on the segmented mitral valves. With this, patient-specific mitral valve replicas can be manufactured that may help heart surgeons to get a more precise understanding of the mitral valve preoperatively and to plan the most effective surgical repair technique. The automation should facilitate independent and mass clinical application. We equipped a heart clinic with our system and manufactured patient-specific mitral valve replicas for several patients. A heart surgeon planned mitral valve repair with them. We present one of the cases.