DE2326864A1 - HIGH FREQUENCY CONTROLLED PACEMAKER - Google Patents

Description

The invention relates to radio-controlled means for exerting stimuli on the heart '(pacemaker) _{9 s} may be connected to an implanted heart pacemaker having built-in battery to the desired type of power supply automatically or manually to control _s particular with the aim dangerous _& © _s situations ausζusehalten that can arise with battery depletion "

Grant implantable battery-operated pacemakers give the patient maximum freedom of movement and

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convenience compared to radio-controlled devices in which an external _{transmitter 9} to be attached to the patient's body must be used. On the other hand, the radio-controlled devices have the advantage of a practically constant degree of efficiency with a constant height of the external transmitter without the implanted stimulus transmitter being adversely affected.

In addition, the radio-controlled pacemakers offer the Advantage, the amplitude, the frequency and / or the duration to be able to regulate the cardiac stimulation impulses and similar parameters.

At least as well as utilize a certain extent the advantages of both the battery-powered pacemaker that of the radio-controlled pacemaker to köraien _s Is it already proposed ₉ a stimulator to build _s contains a battery-powered and radio-controlled pacemaker in a single housing and provided with a device -IsIr ₉ If the appropriate _s depending on the circumstances the transition from one mode to the other make. For the longest time is sine Such an arrangement operable "with the battery, wherein resorting to the radio control only towards the end of battery life until an opportunity _s erglbt by ¹ to replace the pacemaker surgical intervention, or using the radio control occasionally during the period of use the battery "to extend its service life",

Using such Doppe Is Follow-Up Schrlttmacher "must located on the wide range of the market, pure battery-powered stimulus donors refrain _s

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which often have properties that are are worth striving for.

In addition, it is not possible to use a double drive in ignition devices with metal housings, for example made of titanium, which are used more and more in battery-operated pacemakers, since Such housings provide the battery with better protection than the plastic housings previously used.

The invention is thus based on the object of providing a radio to develop controlled cardiac pacemaker with a battery-operated pacemaker of any well-known Construction can be connected without having to make any change to the latter.

The invention works particularly well in conjunction with use battery-operated pacemakers with titanium housings.

According to the invention is one operated with high frequency energy Pacemaker marked by a matched Recipient / rectifier at an exit connection emits excitation pulses in accordance with the transmitted, pulse-modulated "high-frequency energy, through a Input connector connected to the output of a separate Pacemaker is connected, and by a remote-controlled switch, which can optionally be closed or opening a connection * between the input and the output connection of the device can be switched.

Two preferred embodiments of the invention will now be described with reference to drawings which follow demonstrate: '

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Fig. 1 is a circuit diagram of a first embodiment. one radio-controlled pacemaker according to the invention, connected to a battery pacemaker usual design, with a device to choose .the two types of drive by hand;

FIG. 2 shows a schematic representation of a changeover switch for installation in the circuit according to FIG. 1;

Fig. 3 is a circuit diagram of a second embodiment of the pacemaker according to the invention, with automatic switching between battery and radio control.

According to Fig. 1, a device for exercising stimuli on the heart (pacemaker) with radio control according to a first embodiment of the invention a straight-ahead receiver posture on, which consists of an inductance 10, a capacitance 12, a diode rectifier 14 and a resistor 16 consists. The output line 18 of the receiver is connected to a first contact 2-0 of a fe derbe la constant η switch 22 connected, which at rest assumes the position shown in FIG. 1, with an output line 24, which sends a stimulus signal to the patient's heart muscle, is connected to a further fixed contact 2 6 of the switch 22, which in turn via a line 28 with a, battery-operated Cardiac pacemaker 30 of conventional design is connected. ■

The entire device, the receiver / rectifier 10-16 and the changeover switch 22 with the associated connections includes, is in a plastic housing, which is indicated schematically by the line 31, in which with pacemaker

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ma, included in the usual way ». A ground line 32 is, as usual, connected to a metal plate located outside the housing 31.

Of course, the circuit described above could also be applied to a bipolar or biphasic pacemaker instead of the drawn single-pole or single-phase pacemaker to be connected; in this case the connector 32 would be with the corresponding connector of the pacemaker 30 to associate.

A magnetically operated reed relay can be known as the switch 22 Design serve ^ whose magnetic polarization is chosen so that it is between two successive actuations maintains the position previously assumed. Switching the switch can be made by approximating an appropriate one Poles of a movable magnet are brought about, which is attached to the outside of the patient's body. Fig. 2 shows a possible version of such a switch in a schematic representation. The switch contains a tongue 22 with contacts 22a, 22b, the tongue 22 being made of ferromagnetic Material exists and is mechanically forcibly held in the position shown.

A small holding magnet 34 located in the airtight housing of the switch is not strong enough, to bring the tongue 22 into its second position. But if a matching pole of a more powerful magnet is approached from the outside of the pacemaker, the tongue 22 is attracted to the second position in which it is then held in place by the small holding magnet 34, even if the outer switching magnet (not shown) then it is removed «then becomes an external magnet

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with the pole whose polarity is opposite to the polarity that was used for "the first switching operation, When the pacemaker is approached, the effect of the Halxemagnet is increased 34 reduced so far that the tongue 22 can return to its initial position.

Fig. 2 shows the circuit diagram of part of a pacemaker with automatic switching. With this device, a second receiver is used as soon as an external transmitter is used is set in action and a receiver is able to send the heart muscle a stimulus of such a large amplitude that a real muscle stimulus occurs, the absorbed radio frequency energy, the connection between a battery pacemaker and a stimulation electrode (not shown), which are in connection with the patient's heart muscle.

The dashed line 40 in Fig. 3 indicates a high frequency pacemaker device according to the invention; this device is also made of a suitable plastic locked in. An input terminal 42 is to be connected to the output of a (not shown) battery operated Cardiac pacemaker in one of those shown in FIG Connection 28 can be connected in an analogous manner. An output terminal 44 supplies the stimulus signal to an output line, which is led from there to a stimulus electrode (not shown). Eventually becomes a connection on earth, i.e. placed on a metal plate connected to the patient's cell tissue.

The radio frequency pacemaker device 40 includes a tuned receiver made up of an inductor 48 and a capacity 50 exists. Via a diode rectifier

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ter 5 2, the receiver is connected to a filter composed of a capacitor 54 and a resistor 56. The exit The size of the filter 54, 56 is applied to a resistor 5 8 via an isolating diode. The stimulus tension on the Resistor 58 is connected to output terminals 44, 4-6 via a direct current coupling capacitor 62 out, with a Zener diode 64 placed in parallel with the terminals 44, 46 is to protect the circuit in the event that the patient is subjected to electrical defibrillation must become.

The pacemaker 40 also contains a transistor switch 66, the emitter-collector circuit of which lies between the terminal 42 and the non-grounded terminal of the resistor 58. The base of transistor 6 6 is connected to the collector of a second transistor whose emitter is 68 _s via a polarization resistor 70 to the ground terminal 4. 6

The base of the transistor 68 is connected to a receiver and rectifier circuit which, analogously to the receiver / rectifier circuit described in connection with FIG. 1, has an inductor 7 2, which with the inductor 48, a diode rectifier 76 and one of resistors 78, 80, 82 and capacitors 74, existing smoothing filter is connected.

The circuit of Fig. 3 operates as follows:

When the input terminal 42 from the battery pacemaker (not shown) receives a negative polarity pulse is supplied, the resistor 70 ensures the flow of a basic current of such great strength into the transistor 66 that the transistor remains conductive and thereby

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the transmission of the pulse from the terminal 4 2 on the connection point between the resistor 58 and the capacitance 6 2 and from there to the output terminal 44 is guaranteed.

When the two matched receiving circuits 48, 50 and 72, 74 pick up a pulse-modulated high-frequency energy of the appropriate frequency, the receiver delivers 48, 50 with the associated rectifier and filter circuits on the capacitance 62 stimulus pulses that are at the output terminal 44 appear. At the same time, the receiver / rectifier circuit 72, 76, 74 picks up the radio frequency signal up and right it; this signal reaches the base of transistor 68 via filter 78, 84. The transistor 68 is thereby brought into the saturation state. As a result, the base-emitter voltage becomes of transistor 66 is eliminated, and the transistor is blocked, whereby the transition of the stimulus signal from the Terminal 4 2 connected to the battery pacemaker to the output terminal 44 is blocked. Under these Under certain circumstances, the battery pacemaker works with the transistor switch 6 6 open without any noticeable load and therefore only consumes a very small amount of current, which increases the service life of the battery.

The two described embodiments of the inventive Pacemaker's sqllen only represent possible examples of execution. Within the scope of the invention numerous modifications and variations are possible. For example, in a version with manual switching the switch 2 2 can be replaced by another type of switch with remote control, while the version with automatic changeover has a number of switching

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variations in performance would be possible in order to provide services, that would be equivalent to the services described.

Patent claims :

0S349 / 0S81

Claims (1)

M 9554 Patent claims: ζ 1.) High-frequency controlled cardiac pacemaker, with a matched receiver / rectifier, which emits excitation pulses at an output connection in accordance with the transmitted, pulse-modulated high-frequency energy, characterized in that an input terminal (26; 42) is provided, which is connected to the output of a separate cardiac pacemaker, for example to a Battery stimulator (30) is connected, as well as a remote-controlled switch (22; 66), which is optionally on closing and opening a connection between the input and the output connection of the device is switchable. 2. Cardiac pacemaker according to claim 1, characterized in that that the changeover switch (22) can assume a first position in which it connects the input connection (26) with said output connection (2H), and a second position in which it connects the receiver / Rectifier output connects to said output terminal. 3, pacemaker, according to claim 2, characterized in that that the switch (22) as a proximity switch - 10 - 309849/0581 ter is formed, the most distant by a device is visible, which is brought outside of the patient's body in the vicinity of the switch. Cardiac pacemaker according to Claim 3, characterized in that the changeover switch is magnetically switchable Reed switch designed with a holding magnet (34) is that polarizes the switch (22) in one of its two positions. 5. pacemaker according to claim 1 or 2, characterized in that that the switch is a solid-state device (66, 6 8), which by Radio frequency energy is remotely controllable. 6. pacemaker according to claim S _9, characterized in that the solid-state switch can be operated with the same high frequency to which the receiver / rectifier responds. For: SORIN SOCIETA ¹ RICHERCHE IMPIANTI _V NUCLEARI SpA - 11 - 309849/0 5 81 ft Le e rs e i-t-e