A modular prosthetic valve device for implantation into a patient’s body is proposed. The valve device is designed in the form of two or more modules designed to be delivered unassembled and assembled into the valve device assembled inside the body, for example, inside the body at or near the implantation site. Two or more modules may be a support structure and a valve assembly. The valve assembly may be composed of two or more valve sections. Since the valve device according to the invention is suitable for delivery in the form of modules, it can have a smaller diameter upon delivery compared with pre-assembled valves introduced through the skin and allows the use of a smaller diameter delivery device. The delivery of the valve device in the form of modules increases the flexibility of the valve device during delivery compared to the skin-introduced valve devices known in the art. In addition, the present invention provides a system and method for delivering such a modular valve device and assembling it in vivo. Modules of the valve device can be connected with the help of exhaust wires for the purpose of their sequential delivery to the place of implantation in the lumen in the body or near it, and then assembled by remote manipulation using the exhaust wires. The proposed system may further include a temporary valve that can be installed to maintain valve function during assembly of the device modules. The temporary valve can be attached to the delivery device and installed before the deployment of the supporting structure or after it, or the temporary valve can be attached to the supporting structure and installed during the deployment of the supporting structure. To fasten together the device modules, various mounting mechanisms are proposed.Предложено модульное протезное клапанное устройство для имплантации в тело пациента. Клапанное устройство сконструировано в виде двух или более модулей, предназначенных для доставки в несобранном виде и объединения в клапан