Abstract:
An active medical implantable device with at least two diagnostic and/or therapeutic functions is constructed from separate active implant modules ( 2  to  7 ) which are adapted to the respective desired functions and can be coupled to each other.

Description:
This application takes priority from German Patent Application DE 10 2006 018 851.9 filed 22 Apr. 2006, the specification of which is hereby incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to an active implantable medical device with at least two diagnostic and/or therapeutic functions. 
     2. Description of the Related Art 
     A multiplicity of different types of active implants such as heart pacemakers, defibrillators, insulin pumps, neurostimulators, body function recording devices (so-called “event recorders”), heart support systems, etc. The common characteristic of these implants is that they are designed for a certain application and have a functionality determined by the device manufacture. The latter is generally directed towards a certain disease of the implant carrier that is to be diagnosed and/or treated by the implant. 
     However, many patients have not only a certain disease but also a plurality of or systemic symptoms which require a diagnosis or therapy. Moreover, systemic monitoring may often be all that is required. This is generally difficult to achieve with a predetermined implant because the individual components required for this are systemically associated with other and are subject to mutual influence. 
     Because of the problem outlined there is therefore a requirement for an implant which can be individually matched to complex symptoms or diagnosis requirement of a patient and can be configured so that, if necessary, different types of information can be received at a plurality of points on the body, processed and a suitable therapy in turn derived and applied on the basis of this information. 
     SUMMARY OF THE INVENTION 
     The object of this invention is therefore to provide an active, medical implantable device which can be suitably configured by the doctor during the implantation procedure to meet the individual requirements of the patient. 
     This object is achieved according to claim  1  in that separate active implant modules, which can be coupled to each other, are provided with at least two diagnostic and/or therapeutic functions for these modules. 
     On the basis of this modular system the individual modules can each be designed for a particular application, e.g. for measuring physical or chemical parameters and, based on this, for calculating physiological parameters for diagnosis purposes. Again on this basis a particular therapy can be applied by the active implantable device. The following may be mentioned as examples of such physical and chemical parameters:
         body temperature   electrical values (voltage, current, impedance)   pressure   acceleration   optical values (colour, light permeability)   viscosity   pH value   time       

     Physical parameters that can be determined from the above then include, for example:
         cardiac frequency   respiratory frequency   nerve and brain activity   oxygen saturation   lactic acid concentration   cholesterol content   histamine content   movement (activity)       

     Therapies that can be derived from the above include, for example:
         electrical stimulation (low and high energy), e.g. heart pacemaker or defribrillator)   mechanical stimulation   administration of medicines (e.g. insulin pump)       

     In principle it is possible, on the basis of this concept, to implement one or a plurality of the functionalities listed above in one module, and to provide modules with special tasks, for example the supply of current to the other modules and their intercommunication. In this connection it may be advantageous to provide a base device component whereby the implant modules can be coupled, thus enabling the entire system to be implemented in a compact, “elegant” fashion. 
     The base device component preferably receives multi-functional basic elements for the implantable devices, for example a central control unit, a communication unit and/or a power supply unit for the implant modules. 
     According to an advantageous embodiment a bus system is provided for coupling the modules and, in particular, their control and/or communication, which bus system is constructed, for example, of a plurality of electrical conductors or is designed on the basis of light conductor technology. 
     In this case the bus system may be designed so that the implant modules can, for the purpose of their coupling, be connected in terms of signal transmission and mechanically to the bus system, and preferably installed along it. Modules are therefore “docked” onto the bus system, for which purpose provision is made for the bus system to be guided through the individual modules and the implant modules installed along it, preferably by means of plug-in couplings. 
     However, the modules can also be coupled by means of a wireless bus system, which is particularly advantageous when the individual implant modules are not intended to form a compact, mechanical unit after coupling, but are to be installed distributed in the body. Such a wireless communication can be achieved, for example, with a radio technology such as “Blue Tooth”, an inductive coupling or a galvanic coupling via a conductive body fluid. 
     According to a further preferred embodiment an implant module can be fitted with replaceable sub-modules. The latter preferably deviate from the actual functionality of the implant module so that the latter can be variably expanded in terms of its scope of functions. This addition, or even refitting, may also be carried out at later date after the initial installation of the implantable device, without having to replace the complete implant. 
     Summarising, the implantable device according to the invention allows very flexible adaptation to diagnostic and therapeutic requirements which, even after the initial installation of the implant, can still be achieved at limited expense and without having to replace the entire implant. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features, advantages and details of the invention are evident from the following description of an exemplary embodiment with reference to the attached drawings, in which 
         FIG. 1  shows a diagrammatic representation of an active medical implantable device in a modular design, 
         FIG. 2  shows a perspective representation of such an implantable device with different implant modules, and 
         FIG. 3  shows a sectional perspective representation of an implant module. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The basic concept of medical implantable device  1  can be explained with reference to  FIG. 1 . This has different modules, namely a central control module  2 , a power supply module  3  and a communication module  4 , which is constructed, for example, on the basis of a transponder and via which implantable device  1  is able to communicate with an external base device. Furthermore, implantable device  1  has two diagnostic measuring modules  5 ,  6  for measuring temperature and pressure, and a therapeutic module  7  for electrical stimulation. A temperature sensor  8  is integrated in measuring module  5 , which serves to measure temperature. When the implantable device is installed in a patient body, this sensor records the body temperature. 
     Measuring module  6  serves to determine pressure P in a body part and for this purpose has a measuring cable  9  running from measuring module  6 , at the free end of which cable is fitted a pressure sensor  10 . 
     Therapeutic module  7  has a connected catheter  11  at the free end of which lie stimulation electrodes  12 . The patient body may therefore be electrically stimulated, i.e. a heart pacemaker function may be provided, for example. 
     Modules  2  to  7  are commonly connected together by a bus system  13 , which is coupled via interfaces  14  to each module  3  to  7  for the purpose of signal transmission and power supply. 
     An implementation of the module system represented diagrammatically in  FIG. 1  can be explained with reference to  FIG. 2 . Thus a basic device component  15  represents the “backbone” of medical implantable device  1 . A central control unit SE, a communication unit KE, and a power supply unit EE are permanently installed in this basic device component  15  as multi-function basic elements. In the exemplary embodiment shown diagnostic and therapeutic modules are now provided for coupling to basic device component  15 . For this purpose basic device component  15  has, on the long narrow side of its housing  16 , a coupling bar  17 , which is formed by a corresponding housing groove into which can be inserted mechanically the different modules shown, namely measuring modules  18 ,  19 ,  20 ,  21 , for example, with their respective module heads  22  to  25 . Module heads  22  to  24  are shown in  FIG. 2  in a position in which they have not yet been slid through as far as coupling bar  17  (on the left in  FIG. 2 ). Measuring module  21  and therapy module  26  are shown in the condition where they are not yet docked. 
     All measuring modules  18  to  21  have measuring cables  27  to  29  running from module heads  22  to  25 , on the free ends of which cables measuring sensors  30  to  32 , e.g. for pressure, pH value or the like, are in turn arranged. In measuring module  18  temperature sensor  33  is inserted directly into module head  22 . 
     Therapy module  26  has on its module head  34  a catheter  35  which supports stimulation electrodes  36 ,  37  at it free end. Furthermore, a measuring sensor  38 , e.g. for pressure or temperature, is provided on catheter  35 . 
     To complete the implantable device shown in  FIG. 2  a sealing cap  39  is also provided, which is placed on the last module head  34  and serves to seal the bus system  13  guided through module heads  22  to  25 ,  34 . Bus system  13  is constructed so that it extends via basic device component  15  and modules  18  to  21 ,  26  through suitable plug-in connections  40  between module heads  22  to  25 ,  34  to basic device component  15 . 
       FIG. 3  shows in sections catheter  35  in the region of the distal end. It can be seen from this that measuring sensor  38  may itself be designed in turn as a replaceable sub-module  41 . As already mentioned, this supports a measuring sensor, e.g. for pressure or temperature. The functionality of sub-module  41  is therefore of a diagnostic nature, whilst stimulation electrodes  36 ,  37  on therapy module  26  produce a therapeutic effect. 
     Sub-module  41  may be inserted in a corresponding recess  42  in catheter  35 . Here the coupling to the control module (not shown here) is made by a plug-in connection  43  to bus system  13 . 
     It should be added that modules  18  to  21 ,  26 ,  41  are able to communicate uni-, bi- or multi-directionally with each other and with the central control module via bus system  13 . For control, a master-and-slave control system, with reference to the hierarchical arrangement of modules  18  to  21 ,  26 , can be implemented.