The present invention relates to a medical apparatus for the therapeutic treatment of an insufficient cardiac valve (3a, 3b). The aim of the present invention is to specify a medical apparatus which enables the therapeutic treatment of an insufficient cardiac valve, such as, for example, the mitral valve (3a) or the tricuspid valve (3b), which is arranged between a ventricle (1a, 1b) and an atrium (2a, 2b) of the heart, in a manner as simple as possible and as gentle as possible for the patient in a minimally invasive intervention. For this purpose, the medical apparatus according to the present invention comprises at least one valve means (10) which is designed to prevent in the implanted condition of the medical apparatus a systolic venous reflex return of blood from the atrium (2a, 2b) of the heart into at least one vein (4a, 4a′, 4b, 4b′, 4c, 4c′) which belongs to a venous system (4) which leads into the atrium (2a, 2b) of the heart.