DE2112583C2 - Device for monitoring and controlling the human heart function - Google Patents

Description

3 4

Μ The invention relates to a device for the very quick termination of an occurring tachycardia

^ Monitoring and controlling the heart function of the person with a high degree of security, whereby the device

% see, with a Detek connected to electrodes, automatically to the prevailing conditions

H tor for spontaneous electrical heart signals, furthermore with a can adapt.

fl nem stimulation pulse generators connected to electrodes 5 embodiments of the invention are described in the following

H tor for supplying electrical stimulus pulses to the heart lowing explained in more detail with reference to the drawings

P and with a control device for the stimulation pulse In the drawing shows

jy nerator, which the repetition frequency of the spontaneous elec- F i g. 1 a schematic representation of an electrical

I i tric heart signals determined and the repetition rate cardiogram, which the effect of an execution

ΐ§ controls the stimulus impulses in such a way that the stimulus simulation of the device shows

'H' pulse generator Stimulation pulses with a predetermined value. 2 is a block diagram of an embodiment

gf sten repetition frequency emits when the control device, which is formed from three parts A, B, C,

fl direction determined repetition frequency of the spontaneous elec- F i g. 3 shows a modified embodiment of the part

% tric heart signals a predetermined first limit A,

M value falls below and that the stimulus pulse generator ts Fig. 4 a detailed circuit diagram of the execution

p stimulation impulses with a second repetition frequency yields the shape of part A according to FIG. 3,

fg deviates from the specified first repetition frequency F i g. 5 and 6 graphical representations of the effect

'if the sequence frequency determined by the control device of the device according to FIG. 3,

. ^; The frequency of the spontaneous electrical cardiac signals is high. 7 shows another embodiment of part A according to FIG

The higher, second predetermined limit value exceeds 20 Fig. 2,

; There are already devices in the manner of an on-demand F i g. 8 a circuit diagram of the time delay device

: Cardiac pacemaker known (US-PS 33 45 990), both according to FIG. 7,

In the absence of spontaneous systoles, periodic stimulus im- F i g. 9 is a functional diagram of FIG. 7,

! ν- pulse delivered with a predetermined repetition frequency Fi g. 10 a modified embodiment of the

• will. If spontaneous systole occurs, the direction shown in FIG. 7 for the determination of ventricular

! electrical stimulus to which this spontaneous systole leads to- systoles,

no longer occurs, but this electric- F i g. 11 is a functional diagram for FIG. 10,

The stimulus pulse becomes a different embodiment of part A until the end of a period with FIG

: of the same length delayed as that with the spontaneous according to F i g. 2,

Systole begins. Such a device does not show a circuit diagram of the embodiment

different stimulation pulse train frequencies, since Ie- F i g. 12,

it is only ascertained whether a spontaneous systole is on- Fig. 14 a functional diagram of the device

occurs in order to then receive the subsequent electrical stimulus as shown in Fig. 12,

to delay pulse. The time at which this spontaneous F i g. 15 shows another embodiment of part A of FIG

ne systole occurs is irrelevant. 35 device according to FIG. 2,

It is also a device of the initially shown. FIG. 16 is a schematic representation of another

called type known (DE-AS 12 82 802), in the one embodiment of part A of the device according to

directions are provided to determine whether the F i g. 2,

Repetition rate of a number of spontaneous electrical F i g. 17 an example of the function Y (K),

Cardiac signals is less than a lower limit value of FIG. 18 is a circuit diagram of part C of the device

corresponds to a threshold value for bradycardia, according to FIG. 2,

or exceeds an upper limit value which corresponds to a Fig. 19, 20, 21 views of an on the pressure im

Corresponds to the threshold value for a tachycardia. In the case of a myocardium appealing device,
bradycardia, the device delivers stimulus pulses F i g. 22 a block diagram of another Auriüh-

with a base frequency. In the event of tachycardia, the shape of part A of the device according to FIG. 2,
the heart is stimulated with electrical stimulation impulses, the syn- Fig. 23 is a functional diagram of the device

are chronically to spontaneous cardiac complexes, but one according to FIG. 22nd

Have frequency which is a part of the frequency of this die in FIG. 2 shown in general form spontaneous Corresponds to cardiac complexes, for example the management form of the device delivers electrical stimulus half or one third of the tachycardia frequency, 50 pulses with a given period to the heart continues. In other words, when there are no spontaneous systoles, muscle, and at half the frequency an electrical stimulus impulse becomes the Abg <-b ^ electrical stimulus impulses during eifür two of the thin remaining spontaneous waiting time interrupted when a spontaneous systo-complexes is delivered. Clinical trials each have at least one particular kind however, it has been shown that this type of stimulus occurs following a tachycardia 55 stimulus. This willingness to wait can have an adverse effect Device in rare cases we assume at least two different values, their is effective and the reduction in tachycardia is at least less than or at most equal to the smallest not possible with a sufficient success rate. specified period. Here the The object of the invention is to fix the preselection of one of these values by means of the time interval laid down according to the preamble of claim 1 60, the spontaneous systole of the immediately preceding to improve that it separates an occurring outgoing stimulus impulse, the given value Tachycardia ended faster. the waiting time is at least partially growing

This task is carried out by which is the characteristic function of the time interval.

Part of claim 1 specified features in F i g. 1 is shown an electrocardiogram showing the

solves. 65 Mode of operation of the embodiment of the device

Advantageous embodiments and further developments explained. First in this electrocardiogram are

of the invention emerge from the subclaims. three spontaneous systoles SS can be recognized. After the third

The device according to the invention enables a spontaneous systole no more spontaneous systole occurs

and there is a certain time / wait in a known manner. If no systole is shown during this time, the automatic device emits a stimulus pulse / which is immediately converted into an electrosystole ES in the electrocardiogram. If no spontaneous systole occurs, as with conventional pacemakers, three successive stimulus pulses / are generated which are separated by the time period X , which represents the predetermined stimulus period in the absence of extrasystoles or spontaneous systoles. After to the third pulse, a renewed spontaneous systole SS I appears, which is separated from the immediately preceding pulse / by a time interval K 1. From this point onwards, the embodiment of the device allows a waiting time represented by Y ₁ in the drawing to elapse (you can also see at / 'the point in time at which a stimulus pulse would have occurred if 5Si had not occurred). If, as shown in the drawing, no new spontaneous systole occurs during the period Y \ , the device sends out a stimulus pulse / ι at the end of this period. If no new spontaneous systole occurs after I \ , the device resumes stimulation with period X by emitting pulses / as shown in the drawing. If a new spontaneous systole occurs after one of these pulses, a new waiting time begins to run, and if no spontaneous systole occurs during this waiting period, a stimulus pulse is sent to the heart muscle at the end of the waiting period.

The waiting time Y, such as B. Y \, in the described embodiment of the device, can assume several different values, these values preferably being smaller, the smaller the time interval separating the spontaneous systole from the previous stimulus pulse, e.g. B. K- is. The example shown in the drawing shows more precisely that Y \ is smaller than the period X.

If a new spontaneous systole occurs before the end of this waiting time, generally designated Y , a new waiting time is set. In a first embodiment, this new waiting time, like the waiting time V, is selected this time as a function of the time interval that separates the new spontaneous systole from the previous spontaneous systole, namely SSi. In a second embodiment, in contrast, the new waiting time is fixed and preferably equal to the predetermined stimulus pulse period (X in the drawing). This means that if two spontaneous systoles occur in direct succession, the second systole is interpreted as a stimulus pulse and the normal stimulus pulse repetition rate is resumed with the predetermined period X.

In a special embodiment, the different values of the waiting time (vie ζ. Β. Vi) are discontinuous, with the highest values generally attained for the most delayed spontaneous systoles while the lowest values occur for the most premature spontaneous systoles.

If you z. B. Assuming a predetermined period X of 900 ms, the waiting time V is 600 ms. if the interval separating the spontaneous systole from the immediately preceding stimulus pulse with the duration K is less than or equal to 500 ms; Y = 800 ms. if K moves between 550 and 750 ms The different values of the waiting time are therefore 600 and 800 ms. In all of these cases, as mentioned above, the smallest value of at least the waiting time is smaller than the duration of the period X.

In a preferred embodiment, however, the different values of the waiting time are evenly graded, and the waiting time is therefore a continuous, generally increasing function of the time interval which separates the last pulse from the subsequent spontaneous systole, this function being able to have steps, in particular when when the interval approaches the value of the predetermined period X , or, on the contrary, when the interval K becomes very small.

Nevertheless, the continuous function V of K can assume a decreasing part for certain intervals of the change of K in certain applications.

So shows z. B. F i g. 17 is a graph of this function. The waiting time Y before stimulation is plotted on the ordinate, while the interval separating a spontaneous systole from a directly preceding stimulus pulse is plotted on the abscissa, reduced by 400 ms (for reasons of expediency, which will be explained later). The value K - 400 ms is plotted on the abscissa.

This curve can have horizontal steps, in particular for the largest values of Y. which, moreover, can be greater than the period X.

In the case in which the greatest values of the waiting time Y are greater than X, ie greater than the stimulus period in the absence of spontaneous systole, the limit value of the interval K. is below which Y is smaller than X and above which V is greater than X is, preferably in the second half of the period X. which follows the stimulus impulse which immediately precedes the spontaneous systole that triggers the waiting time. This limit value is represented by m in FIG. 1. Of course, Y is equal to X if Y is a continuous function of K , if K is equal to the Αυ5ΐ5Πιι separating / from M

In one embodiment of the device, the waiting time is always greater than the interval separating the spontaneous systole from the immediately preceding stimulus pulse or, in the case of a modification already described, from the immediately preceding spontaneous systole. That is, Y is greater than K. In contrast to this, in another embodiment Y is always smaller than K. In this particular embodiment it is obviously not possible to obtain three spontaneous systoles SS in the electrocardiogram which are separated from each other by the same time intervals as in the left part of FIG. 1 are separated. That an effective control of the heart muscle is ensured by the fact that it gives him the least possible time to form spontaneous systoles course at a third Ausfühningsform Y may be as K larger when K is large and to be smaller than K This variant has the advantage, if K is small You control the premature spontaneous systoles by lengthening the waiting time for the delayed spontaneous systoles and thus stimulate the heart muscle to beat with its own rhythm, but not with too high a frequency.

As shown above, the delivery of the stimulus pulses occurs when a spontaneous systole of at least occurs carried out in a certain way. Systoia is understood to mean any electrical heart signal with sufficient intensity to be received by at least one of the electrodes, whether or not results in a myocardial contraction or not. In a preferred embodiment, only those spontaneous systoles taken into account after the end

the duration of the retraction of the myocardium, while the systoles that occur during this period remain unconsidered. This retraction time is for a normal heart rhythm, for example On the order of 300 to 400 ms after a spontaneous systole or an electrosystole. In any case can be the vvabl the type of spontaneous systole that one taken into account in the same way both as a function of the shape of the systole on the electrocardiogram and can also be performed as a function of the origin of the spontaneous systole. So can the systoles of a certain Type z. B. be limited to ventricular extrasystoles, which are often the most dangerous.

In this case one can either use a detection electrode with a device for discrimination of the shape (which will be described below), or one can put a number of electrodes in or place on the heart muscle, the first excited electrode determining the origin of the spontaneous systole.

In one embodiment of the device, the stimulus pulse transmitted normally or after the waiting time described can either be at least doubled, or its intensity can be adjusted automatically, it being increased in the event of a spontaneous systole when the time interval K is reduced. In this manner, a more secure electrical control is achieved of the heart muscle, the electrical- ^"1 conductivity properties change as a function of the instantaneous frequency of the systole.

In another embodiment of the device, the basic frequency of the stimulation, ie the predetermined period X, is temporarily increased. You can also reduce Y at the same time to adapt to this new period X. These changes can be determined by various factors, as described below.

If it is found that too large a number of spontaneous systoles is generated in spite of a change in the waiting time V, these spontaneous systoles are automatically counted, and if too large a number of spontaneous systoles is counted for a given number of systoles, the basic period X becomes automatic decreased.

In another modified embodiment, this basic period is a function of the internal pressure of the myocardium changed, which is determined in a manner described below. It is alike possible the peculiarity of the blood bag with the help of suitable Detectives to determine the rhythm and form of the irritation and the waiting time to act.

General description of the device

The embodiment of the device comprises a time base device controlled devices for the delivery of electrical stimulation pulses with a predetermined period to the heart muscle with the help of at least one electrode, preferably one Heart electrode, time delay means for controlling these devices after a waiting time by placing them temporarily replace the time base device, the Time delay means can be kept in at least two different states for which said Waiting time each has a different value, at least one of these values being smaller or at most equal to the specified period is a means of determining the spontaneous cardiac systoles, which comprise at least one electrode, preferably a heart electrode, and which are determined current impulses corresponding to spontaneous systoles to the time delay means in order to reduce the waiting time to trigger which corresponds to the state in which the time delay means are at this point in time, and means for sequencing the time delay means as a function of the time elapsed since the last stimulus pulse from one state to the other.

The devices for delivering stimulus pulses can be formed by a stimulus pulse generator, the one stimulus pulse to at least one Hefert electrode, if it is either from the time base or from the Time delay means is controlled at the end of a waiting time.

The time base can likewise be of any type already known. It is Z. B. possible to use a capacitance as the time base which is charged periodically with the aid of a charging resistor and which actuates an element such as a programmable unijunction transistor (PUT) when the charging potential is sufficient. It is equally possible to use an astable multivibrator circuit which periodically triggers the excitation or the stimulus. As a modification of this, a pulse generator that operates at a given frequency and with any counters, e.g. B.

connected to flip-flop circuits or a stair integrator. This counter enables stimulation impulses to be sent out when the specified number of impulses has been counted.
The time delay devices respond to spontaneous systoles delivered by sensors and can at least assume different states in order to trigger the waiting time according to the state in which they are at the point in time at which they are actuated, and in order to actuate the stimulus pulse generator at the end of said waiting time.

It is possible to use two capacitors as time delay devices, one each Have charging resistor, and both with a trigger element, such as. B. a programmable Unijunction transistor are connected, one of the capacitors starting from a higher initial potential is charged than the other capacitor, but with a potential increase as a function of Time dir is smaller than the rise in potential of the other capacitor, such that the potential of the other Capacitor reaches the potential of the first capacitor over time and so the element such. B. the programmable unijunction transistor triggers the later the second capacitor with respect to the first is switched on, the longer the time that elapses until the potential of the first capacitor is reached is. In this embodiment, the state in which the time delay devices are, by that of the first capacitor at the moment in which a spontaneous systolic impulse is sent out which turns on the second capacitor determines the assumed potential It is understandable that instead of the charging of the capacitors, the discharging of the capacitors is also used could.

In another embodiment, the time delay devices from a single consortium

capacitor, which is connected to a discharge resistor, the capacitor via a charging resistor is charged, which may be the same as the discharge resistance, which, however is preferably another. When a spontaneous systolic impulse is sent out, the charge of the Capacitor interrupted, and the capacitor discharges through the discharge resistor until the Potential reaches a fixed value at which the stimulation is triggered by a suitable element. It is understandable that the greater the charge potential when this pulse is sent, the greater the discharge time until the fixed potential that forms the threshold for the emission of the stimulus is reached. In this The case becomes the state in which the time delay devices are by that of the capacitor when a spontaneous systole occurs, La-

ok

15th

In another embodiment, the time delay devices consist of several monostable ones Flip-flops that have different tilt periods in the unstable state, at least one of these tipping periods is less than the specified period. These different flip-flops are connected to an electronic switch arrangement, the spontaneous systole impulses successively as a function of time to the various monostable multivibrators. The state the time delay devices is thus determined by the position of the electronic switch.

In another embodiment the time delay means comprise a digital pulse counter; this pulse counter counts a certain number of pulses that come from a pulse generator, and when the counter has counted the last of these pulses. it causes the stimulation pulse generator to be triggered. The number of pulses counted by this counter is determined by, for example, a different number of pulses which were previously counted, the state of the time delay devices being determined by the previously counted number of impulses and thus through the state of the counter is set.

The means for successively transferring said time delay devices from one State in the other as a function of the time elapsed since the last stimulus pulse can be in the same Way to be construed in different ways. For example, you can have a potential source and comprise a charging resistor connected to a capacitance. The charging of this capacity starts like this Time of occurrence of an electrical stimulus pulse or, in a modified embodiment, according to a specified time after the occurrence of one such Impulse. That of this capacity at the time of the occurrence of an established spontaneous systole The potential reached determines the state in which the associated time delay devices, z. B. a discharge resistor connected to the capacitance are located. In the above case, in the time delay devices comprise two capacitors, there are means for overhead of the time delay devices from one state to the other of an energy source and a resistor for the slowest charging of the capacitor. In the case of the above, this is only one capacitor related embodiment the same.

In the above-mentioned embodiment, in which the time delay devices have several monostable, include successively excited flip-flops, the means exist for successive Transfer of the time delay devices from one state to the other from the electronic one Switch arrangement from an initial state corresponding to the occurrence of a stimulus pulse as a function of the time operating means.

The means for transferring the time delay devices from one state to the other can equally be digital means comprising a pulse generator and a counter e.g. B. after is reset to zero with each stimulus pulse. After the occurrence of such an electrical stimulus pulse the counter starts counting the pulses received from the pulse generator again. At the time of When a spontaneous systole occurs, the state of the time delay devices is indicated by the number of the counted pulses. When the time delay devices likewise comprise a counter, the latter counter counts a number of pulses, determined by the number of pulses previously counted by the first counter up to that moment is. The number of pulses counted by the latter counter can for example be equal to the number of the previous ones counted pulses, in which case the waiting time is equal to that of a spontaneous systole immediately preceding artificial electrosystole separating time interval or different from this can be.

In all of these embodiments it is advantageously possible to use electrical or electronic components jointly, for example, for the time base and / or the time delay devices and / or the Means for successively transferring the time delay devices from one state to the to use others.

The detectors for the spontaneous systoles comprise at least one sensor electrode, which can optionally be the same as the stimulus electrode, and which makes it possible to determine the electrical phenomena of the heart. Preferably, means are provided for temporary blocking in order to prevent the determination of the triggered cardiac systole which directly follows an artificial electrical stimulus ES Follow stimulus ES so that the phenomena that occur during the retraction period of the myocardium are not taken into account. Finally, the detectors can comprise various selection means which make it possible to only supply such pulses to the time delay devices either as a function of the time at which such a systole occurs or as a function of its origin (auricular or ventricular), and this either on the basis of the position of the electrode which first ascertains the electrical appearance of this systole, or with the aid of means responsive to a characteristic, for example the shape, duration, amplitude, adjustment swivel, vector, etc., of the electrical systole impulse.

The device described above can have various embodiments. It actually can happen that on an established spontaneous, the time delay means triggering systole before the end of the waiting period a second spontaneous systole follows In a first embodiment, means are provided for the various electronic components

of the device to its initial state in such a way that such a second systole of df device exactly as an artificial stimulus impulse is perceived.

In a further embodiment, means be provided in order to restart the time delay devices with a waiting time that corresponds to the state of the time delay devices at the time of the occurrence of the second systole. In this case, the time delay devices are preferably halved, as follows can be seen.

Detailed description of embodiments A) First embodiment:

A device is never the first embodiment two capacitors, the charging of which takes place at different speeds, the potential of the one capacitor should reach the potential of the other capacitor. This device is described below on the basis of FIG. 2,3,4,5 and 6 described:

In Fig. 2 the device comprises three parts A, B and C, only parts A and B of which are described here; Part C is described below because it is not absolutely necessary for parts A and B to function.

Part B comprises an intracardiac catheter 1 terminating in a plurality of electrodes 2, some of which are positive while the others are negative. These electrodes 2 serve both for scanning and for stimulating the heart muscle. The electrodes 2 are connected to an input amplifier 3 of any known type which is connected via a filter 5 to a trigger circuit 6 for shaping the pulses sensed by the electrodes 2. Uie trigger circuit 6 is connected to a monostable multivibrator circuit MS whose unstable period has a duration of z. B. has 5 ms. The output of the multivibrator circuit MS is connected to a detector line 8. Part B merely serves in a manner known per se as a converter for converting the electrical signals received from electrodes 2 into calibrated 5 ms signals or pulses on line 8.

Part B further comprises a power line 9 for supplying stimulus pulses originating from the device 10 forming a stimulus pulse generator to the electrodes, the device 10 being of a known type and being controlled by the stimulus line 11.

In Fig. 3 shows the device A in detail. In particular, the lines 8 and 11 are shown in this figure

The F i g. FIG. 4 shows a detailed circuit diagram of the circuit shown in FIG. 3 part shown.

When entering part A , line 8 is led to an AND gate ET2 , the mode of operation of which is described below. The time base is formed here by a pulse generator 12, which is described further below and which normally emits pulses ^ with a predetermined period, which is, for example, "900 ms, to an output line 13. This pulse generator includes in known way a: capacitance CC with a preferably adjustable charging resistance and e.g. 0.5 MOhm, this capacitance with a programmable unijunction transition

^; ; disturbance (PUT) D 13 T 2 It follows that in the absence of spontaneous sysiols or spontaneous electrical cardiac signals, the pulse generator or the time base 12 ensures the functioning of the heart muscle by activating the device 10 every 900 ms so that it generates a stimulus pulse / releases, which is immediately followed by a ^c lectro-cardiac systole ES , as can be seen in particular from FIG. 5, in which the first curve ECG represents the electrocardiogram as it occurs at the electrodes 2. More precisely, the signal sent periodically from the time base 12 is fed via the line 13 to a 2 ms monostable circuit MSS for pulse shaping, the output of which is connected to the line 11. Another output 14 of the monostable circuit MSS leads each to a 200 ms monostable circuit MS 1 and a 400 ms monostable circuit MS 3, one output MS 3 of which is connected to a 350 ms monostable circuit MS 4. The output of the monostable circuit MS 4 is fed to a 150 ms monostable circuit MS 5. The output of the monostable circuit MS1 is connected to the three AND gates ET 1, ET 2 and £ T3. An output of MS 3 is in turn connected equally to the gates ET \, ET2 and ET3 . An output from MS 4 is fed to gates ETi and £ T3, while its unstable output is connected to ET2 . Finally, an output of MS 5 is connected to gate £ T3, while its unstable output is connected to ETX .

On the other hand, the detector line 8 is similarly connected to the gates ETX and £ T3.

The gate £ T2 is connected via a line 15 to an OR gate OUX , to which the output of MS 3 is also connected. This gate OU 1 has its output connected to a blocking device A 2 for the pulse generator 12, the blocking device in particular comprising the transistor Q 19. The output of the gate £ T2 is connected to a 600 ms monostable circuit MS 2, the output of which is also switched off to the gate OU X. The output of another 400 ms monostable circuit MS 7, which is controlled by the output of the gate £ T3, is also connected to this gate OUX. The output of MS 7 is on the other hand connected to an OR gate OU 2 , to which the output of MS 3 is also connected. The output of gate OU 2 is connected to a transistorized locking device AX which is connected to a device 16 for controlling the delay device 16. This comprises a capacitance CD of z. B. 1.6 microfarads, which have a variable resistance of z. B. 200 + 100 kilohms is charged, the potential of this capacitor via a conventional impedance matching circuit 17, the z. B. the transistor Q 17 is connected to the gate electrode of the transistor PUTaes pulse generator 12 The mode of operation of the device is as follows: As has been shown, the pulse generator ensures the stimulation of the heart with a period of 900 ms in the absence of spontaneous systoles. At the point in time at which the pulse generator 12 causes a signal to be sent to MS 6, this signal continues to be forwarded via line 11 to device 10 and likewise causes MS X to tilt for 200 ms and 65 MS 3 via line 14 for 400 ms. In this way the stable output of AiS 1 blocks, i. h-MS1, the gates ETX, ET2 and ET3 for the duration of 200 ms, as shown in FIG. can be recognized in this way none of the

Electrodes received signal are passed through the gate. At the end of the 200 ms duration, MS 1 stops blocking the three gates. In any case, AiS 3 blocks the three grids for another 200 ms, ie up to 400 ms after the / pulse. During the same period of time, the unstable output of MS 3 connected to the devices A 1 and A 2 , via the two gates OU 1 and OU 2, blocks the pulse generator 12 and the part 16 of the time delay means. It can be seen at the beginning of FIG. 5 that the potentials V and V of the capacitances 12 and 16 are held at their initial values for 400 ms. At the end of this 400 ms, MS 3 returns to its stable idle state, and this causes the blocking of the three gates ETi, ET2 and ET 3 to be terminated, while AfS 4 toggles for 350 ms at the same time, as can be seen from FIG. 5, at the same time enables AiS 3 the distribution of the charge on the one hand on 12 and on the other hand on 16, ceasing to act on devices A 1 and A 2 .

During the renewed 350 ms, the gate ET2 is no longer blocked by AiS 4, while in contrast to this, the gates ETi and £ T3 are blocked by the stable output of AfS 4. At the end of 350 ms, AiS 4 returns to its idle state and thus triggers AiS 5 for 150 ms. During the latter 150 ms ETi is switched through, while ET3 is blocked by AiS 5 In conclusion, the three gates £ 7 1, £ T2 and £ T3 work as follows:

During 400 ms the three gates are blocked, during 350 ms £ T2 is open, while the other two gates are blocked and during the last 150 ms ETi is open while the other two gates are blocked.

At the end of the 900 ms (ie after a charge of 500 ms, if no charge has taken place during the 400 ms at the beginning) the potential V 'of the capacitor CD of the device 16 has reached the potential V of the capacitor CC of the time base 12, which is a Part of the initial potential V ₀ is smaller than the initial potential V'o of the capacity CD of 16, but which increases faster than the potential of CD. At the point in time at which the two potentials V and V "become the same, ie 500 ms after the start of charging, the transistor PUT of the device 12 is again triggered by the equality of the potentials and sends a pulse to 13 that generates a stimulus / and the Commences a new cycle (in practice, the transistor PUT is activated when there is a slight potential difference between the potentials of the charges V and V of the capacitors of 12 and 16, regardless of the absolute value of the respective potentials of the capacitors).

It is now assumed that a pulse SS resulting from a spontaneous systole occurs during such a predetermined period. This pulse SS (Fig. 5) is suitably shaped by device B and appears on line 8. If it appears during the first 400 ms that follow, this pulse cannot pass through any of the gates ETX, ET2 and £ Go through T3 and the device will function as before. If, on the other hand, the pulse occurs between 400 and 750 ms, the gate £ T2 is open and the corresponding pulse running on the line 15 briefly blocks the pulse generator 12 via A 2, which in turn starts the generator starting from its initial potential V _0. It will be understood that the potential V "of the charge of the capacitance of 16 is the _{greater at the moment when the pulse generator 12 takes its charge from its output potential V 0} , and that the time which elapses until the potential V of When the spontaneous systole occurs just after the first 400 ms, the charging of 12 and 16 begins practically at the same time, and a stimulus pulse begins / is consequently emitted 500 ms after this impulse of spontaneous systole.If, on the contrary, this impulse of spontaneous systole occurs just before 750 ms, this is the time that elapses until the potential of the charge of 12 reaches that of the charge of 16, for example equal to 700 ms.

The waiting time Y is longer, the longer the interval separating the spontaneous systole from the last stimulus impulse, ie the time K, is Di. it is expected that spontaneous systole is no longer dangerous. It is understandable that this duration of 750 msec can be decreased or increased depending on the patient, this duration very well being equal to the predetermined period of 900 msec; in this case it is assumed that all spontaneous systoles occurring after 400 ms are undesirable, but that the more they are delayed, the less undesirable they are.

If now with the device mentioned above a spontaneous systole SS occurs not before but after 750 ms z. B. at 800 ms, the gate £ T2 is no longer permeable, but ETi is kept open for 150 ms with the help of ASS5 (Fig. 6). The corresponding pulse passing through the gate ETi now triggers the monostable circuit AiS 2 for 600 ms. During these 600 ms, AiS 2 is in the tilted state and keeps the pulse generator 12 out of operation via the gate OU 1 in such a way that the capacitor 12 is not charged. At the end of this 600 ms, AiS 22 returns to its stable state, and the pulse generator 12 begins to start up again in order to bring the potential V of its capacitance back to the potential of the charge V ' of 16, the latter charging potential V having sufficient time to to assume its maximum value V \ and to hold it during the 600 ms. Under these conditions, the time V equals 600 ms plus the time required for V to take on the value of V \ . This time is, for example, equal to 700 ms. The waiting time Y is thus 1300 ms, beginning with the occurrence of the spontaneous systole.
It is clear that the same is true for any pulse SS that occurs after 750 ms. It can be seen that in this embodiment for delayed spontaneous systoles> is greater than the predetermined period of 900 ms.

After a stimulus pulse / was delivered via line 11, it is assumed that a spontaneous Herzsy stole is detected after a time K which is between 400 and 750 ms, e.g. B. at 550 ms (Fig. 6), ie during the rend of time, tilted during the AiS4 and ET '.

is switched through. As can be seen from the preceding zi, this pulse brings the capacitance CC voi 12 back to the output potential Vo, 12 being triggered immediately and the variable waiting time Y follows. If a new spontaneous systole occurs before the end of this period, three cases may arise:

In the first case, AiS4 is still in the tilted state This case (not shown in the drawing) is very rare because it would mean that the two spontaneously nen systoles are separated by at least 350 ms. Ii

In this case, the pulse runs again in a simple manner over £ 72 and leads the capacitance CC of 12 back again to the output potential Vo , which is immediately charged again and causes a new waiting time Y , this time longer.

In the second case (not shown), MS 4 has returned to the idle state, but MS 5 has tilted. The result is then the same as in the case of a delayed systole (as shown above), & h, a new waiting time of 1300 ms is triggered In the third, in FIG. 6, MS 5 has already returned to the stable state, and none of the monostable circuits MS1, MS 3, MS 4 and MSS has flipped. Under these conditions, gate 73 is open and this impulse of the spontaneous systole SS causes flip-over MS 7 for 400 ms, which during this 400 ms via the blocking devices A 1 and A 2 keeps the devices 12 and 16 at their initial potential. After 400 ms, 12 and 16 are triggered at the same time, and 500 ms are required for the potential V has reached the potential, whereby a stimulus pulse is now delivered after a delay that is 900 ms after the occurrence of the second spontaneous systole.If a third spontaneous systole occurs before the end of this waiting time of 900 ms, it does not happen if it is at least 400 ms after the second spontaneous systole, ie as long as MS7 is tilted occurs, while if the third spontaneous systole occurs after 400 ms it triggers MS 7 via £ T3 for 400 ms and it we d caused a new waiting time with a duration corresponding to the specified period. Under these conditions, the device described does not intervene in the event of a tachycardia being activated.

It follows that the device according to FIG. 3 enables the time Y to be adjusted as a function of the time K when a spontaneous systole is determined and selected after an electrical stimulus pulse supplied by the device. In contrast, when there is a second spontaneous systole immediately following a first spontaneous systole, the device does not intervene to disturb the tachycadic rhythm.

Another embodiment of the device A will now be described with reference to FIG. 2 described:

In this embodiment, the detector line 8 is connected in the same way to three gates £ 701, £ 702 and £ 703 guided. These gates are opened in the following way:

After a stimulus pulse / or after a sampled systole SS , gate £ 702 is blocked for 400 ms, while the others are switched through during this time (with the exception of £ 701, which is blocked during the first 100 ms via MSOL after a stimulus / can). After 400 ms, MS 03 switches to the stable state, £ 702 is opened via MS 04, and £ 701 and £ 703 are blocked for 350 ms. After this 350 ms £ 702 is locked again and £ 701 and £ 703 are opened.

In this modified embodiment, MS 03 has an output which is connected to a flip-flop FFOl, which can be toggled via a line 11 (via POl) in order to block the capacitance of a device 016 corresponding to the device 16 explained above and to keep discharged. If MS 03 returns to its stable state after the first 400 ms and MS 04 flips in the process, it can be seen that M503 flips the flip-flop FFOl, which means that the capacitance of 016 can be charged. After a certain time, e.g. B. of 500 ms in the selected example, the potential of 012 has reached the potential of the capacitance of 016. It should be noted that in

In this case, 012 charges when a pulse / occurs. However, at the point in time when MS 03 returns to its stable state after 400 ms, it quickly and immediately discharges the capacitance of 012 via a line 01 and via the gate OUOi. After 400 ms, the charging of 012 and 016 starts at the same time, and equality of potentials is reached after 500 ms, and a stimulus pulse is emitted.

If a spontaneous systole SS occurs after 400 ms and before 750 ms has elapsed, it reaches the gate

is £ 702, the output of which is connected to the gate OU 01, as a result of which the capacity of 012 is quickly discharged again, which results in a delay in the capacity of 016 and thus creates the waiting time y.
If, on the other hand, the systole SS occurs after 750 ms, the gate £ 701 is switched through and the impuis is connected to a 500 ms monostable circuit MS 02 via the output of this gate (the duration of the tilting period of the monostable circuits is shown in FIG . 2 entered in the monostable circuits). After a waiting time of 500 ms, this monostable circuit discharges the capacitance of 012, the charge of which again approaches the value of 016 , and a waiting time Y that is greater than 1100 ms results
If the systole occurs during the first 400 ms, the gate £ 703 is open and the pulse simply resets the time base 012 to zero, ie it discharges the capacity of 012.

B) Second embodiment

In the second embodiment, the time delay means comprise a capacitance with a discharge resistor, and when the discharge potential reaches a given small value, control them Facilities the delivery of stimulus pulses.

Three different variants of this second embodiment are described below.

The first variant is shown in FIGS. 7,8,9 shown.

In this first variant, a new type of device replaces the device A described above. In this new device according to FIG. 7, a detector line 8 is provided, a branch of which crosses the device and is connected to the input of C at 8 '. The stimulus output 11 coming from the output 211 ' & ·, ·> pulse generator 220 is connected to a 2 msomr.stable circuit MS 206 for pulse shaping and has a branch which is connected to another monostable circuit MS 201 of 200 ms, for example, where this monostable circuit MS 201 the blocking of a gate £ 7201 after the occurrence of an artificial stimulus at 11 for a time of z. B. allows 200 ms. The second input of the gate £ 7201 is connected to the detector line 8 for the systoles. The output 240 of the gate £ 7201 is connected on the one hand to a gate £ 7202 and on the other hand to a flip-flop FF200 and finally to an input 241 of a monostable circuit HVa which is normally blocked by a transistor A 202 which is connected to the output of the gate £ 7202 is arranged. The structure of HVa is detailed in FIG. 8 shown. This monostable circuit is particularly characterized in that it has a charging resistor ^ 'in relation to those

The output 242 of this monostable circuit has a branch which is connected to the second input of the gate ET202 . This output is on the other hand connected to a monostable pulse-shaping circuit MS 206.

On the other hand, an output of flip-hop 200 is led to a blocking transistor A 203, which can block a pulse generator 243, which can simultaneously send pulses to MS 206 and thus stimulate or stimulate the heart muscle. A branch 244 goes from the line 211 and is connected to the other input of the flip-flop.

The mode of action is as follows:

In the absence of a spontaneous systole, the stimulus pulse generator, which can be a pulse generator of any type, for example an integrator, which periodically emits stimulus pulses to MS 206 and then to line 211, emits an artificial stimulus pulse / with a predetermined stimulus period. This pulse is fed to electrodes 2 on the one hand and to MS 201 on the other hand, which blocks gate £ T201 for 200 ms in order to prevent the systole caused by this stimulation from being determined. Finally, this pulse appears via 244 at the flip-flop FFTOO, which, however, was already in the tilted state which enabled the operation of the pulse generator, so that it does not change its state ET202, in such a way that they act on the blocking transistor A 202 in such a way that HVa is suddenly discharged, with WVa already having started its charging via the circuit R'C without the HVa abruptly during the operation of the pulse generator 243 would load. At the output 242 of HVa there is a pulse which is fed to the excitation or stimulation 211, but which, since it immediately follows a pulse from the pulse generator 243, coincides with the QRS wave of the systole caused by the pulse from the pulse generator, such that it has no effect on the heart muscle. In this way, in the absence of spontaneous systoles, the pulse generator 243 determines the heart rhythm.

If a spontaneous systole occurs more than 200 ms after the last artificial electrical stimulation pulse /, the gate £ T201 is open, so that the pulse passes through this gate and FF200 toggles, which in turn blocks A 203 and thus the pulse generator 243. At the same time, this pulse runs via 241, whereby HVa is toggled into its unstable state and causes the discharge of the capacitance C , which this time discharges through the resistor R due to the arrangement of the flip-flop transistor; the output 242 now has a positive potential again. When the flip-flop has discharged, it returns to its stable state and transmits a pulse

242, which is transmitted via MS206 and causes the heart to be irritated. The conductor 244 in turn flips the flip-flop FF200 into its pulse generator

243 and, if no other spontaneous systole occurs, the pulse generator calls with its own rhythms the irritation of the heart emerges.

From the in F i g. 9, artificial electrosystoles ES generated by the pulse generator 243 can initially be seen. Between two successive electrosystoles ES, the charge of the capacitance C via the resistor R ' and the sudden discharge that occurs at the time of the occurrence of the subsequent electrosystole can be seen.If a spontaneous systole SS occurs, the flip-flop FF200 is tilted and stops the pulse generator 243. At the same time the capacitance discharges through the resistor R, and this discharge time is longer the longer the charging time lasted, the duration of the following artificial stimulation after a variable one

The waiting time takes place which depends on the time separating the spontaneous systole from the immediately preceding electrosystole. In general, the time constants are chosen in such a way that the time separating a spontaneous systole from the normally following electrosystole is longer than the time K, which is separates the spontaneous systole from the immediately preceding electrosystole, thereby possibly allowing the heart muscle to beat with a spontaneous rhythm. In any case, it is possible to select this time so shorter that the stimulus device strives in an advantageous manner to bring the heart muscle under control when a spontaneous systole occurs.

It is also on the right half of FIG. 9 it can be seen that if a second spontaneous systole SS occurs after a first spontaneous systole before the end of the discharge of the capacity C , £ T202 is open at this point in time and the systole is led to A 202 in order to discharge the capacity suddenly, which begins to recharge immediately afterwards. The device is therefore always ready for operation, even if the spontaneous systole occurs after an artificial systole, both when the spontaneous systole occurs after an artificial systole, and when it occurs after a spontaneous systole occurs. In the event of tachycardia, the device no longer emits stimulus pulses.

Due to the design of the charging curves and the discharging curves, it is possible in a first variant to use such a discharge resistance R that regardless of the time at which a spontaneous systole occurs after an immediately preceding electrosystole (and of course before the hypothetical electrosystole that of this preceding electrosystole would have followed if no spontaneous systole had occurred) the time Y separating the spontaneous systole from the following electrosystole, i.e. the discharge time of C (unless a subsequent spontaneous systole suddenly interrupts the discharge) is less than the specified period X of the pulse generator 243, the lesser time, however, increasing with the time separating the spontaneous systole from the immediately preceding systole. In another variant it is possible to set R so that the normal discharge time of the capacitance C is less than the period of the base -Y of the pulse generator 243 when a spontaneous systole occurs in a relatively short time after the immediately preceding systole, during the time The rhythm of the base can become larger if the spontaneous systole occurs with a greater delay. In other words, the capacitance C discharges with a time that is smaller than the predetermined period when it has had little time for charging, while it discharges with a time that is greater than X when it has a longer time for the Charge was available.

Reference is made to FIGS. 10 and 11 below.

In this second variant, includes the one shown

Apparatus in the same way has a detector line 8 which, as in the case of FIG. 7, is connected to a pulse generator 243 which emits a basic rhythm, the generator being started or stopped in the same way. In the example according to FIG. 10 the output of the gate ET201 is neither connected to a monostable circuit such as HVa nor to a gate such as £ T202.

Before the device according to FIG. 10, it will be recalled that spontaneous cardiac systoles can have sinus systoles which are generally not dangerous and ventricular systoles which can be dangerous even if delayed. From Fig. A very schematic electrocardiogram can be seen in FIG. 11, which shows on the one hand sinus systoles 55 / and on the other hand ventricular systoles SS V, the second of these two spontaneous ventricular systoles having a positive and a negative peak

From Fig. 10 it can be seen that the detector line 8 has a branch which is connected to a trigger circuit 246 known per se, di ',. if the potential at 8 exceeds a predetermined value L) , a square-wave signal 247 with a predetermined potential is emitted during the entire time during which the potential at 8 is greater than or equal to U. The output 248 of the trigger circuit is connected on the one hand to a monostable circuit MS 207, the unstable state of which can be regulated between 60 and 150 ms, for example, with the aid of a conventional potentiometer. On the other hand, the line 248 branches into a line 249 to a first differentiator with a capacitance C201, a reverse-biased diode D 201 and a resistor R 201, which connects the common connection point of the capacitance with the diode to the output of MS 207 Branch 250 is connected to a second differentiator, which consists of a resistor R 202, a reverse-biased diode D 202 and a capacitor C 202 connected between the output of M5207 and the common connection point of D 202 and R 202. The diode D 201 is led to a monostable circuit M5208, the output 251 of which is connected on the one hand to a monostable circuit HVi of a type similar to WVa and on the other hand to a gate ET222 , via which it is possible to use a blocking transistor A 222 to increase the capacitance suddenly discharged from HVX. A line 245 is connected on the one hand to the output of ET222 and on the other hand to the stimulus line 11. The second input of the gate ET222 is connected to a branch of the output line 242 'of HV 1 connected to M5206. In the same way, the output of Λί5209 is connected to HV2 via ETUI, whereby the structure is exactly the same as that for HV \ and HV2 is connected to Λί5 246 via line 242 ".

The mode of operation of the pulse generator 243 corresponds to the case of FIG. 7, and if a systole determined with the aid of FIG. 8 occurs, a corresponding pulse is converted via the trigger circuit 246 into a square-wave signal, the duration of which corresponds to the size of the systole. At the beginning of the signal sent by the trigger circuit 246, the monostable circuit MS 207 toggles for a predetermined duration, for example for 90 ms, whereby the output connected to R20i and C202, which normally has the potential zero, is made positive. Two cases can arise, depending on whether MS 207 returns to the stable state before the signal of the trigger circuit 246 falls or whether MS 207 reaches its stable state after the end of the square-wave signal from the trigger circuit. In the first case, it is assumed that there is an additional ventricular systole. In this case, the negative slope of the trigger signal (i.e. the end of the square-wave signal) appears at C 202 at the point in time when MS 207 returned to its initial state and the potential at R 201 is zero. The negative flank can pass through the diode D 201 and toggle the monostable shaping circuit Af5208, the unstable state of which can last for example 2-5 ms and which then supplies a signal to 251 which, as in Case of fig. 7, brings HV 1 into its unstable state and discharges the capacity of HVi. At the end of this discharge, the duration of which is longer, the later the additional systole occurs, ie the more time the capacity is available for charging, HVi sends a stimulus via MS 246 and line 11. Gate ET222 was switched on while HVi was in the unstable state, and if a second additional ventricular systole had passed through MS 208, HVi would have been suddenly reset to zero, as in the case of FIG. 10 goachah. Line 245, if any stimulus occurs at 211, allows the capacitance of HVi to drop to prevent it from charging all at once.

In contrast, if the end of the trigger signal occurred before MS 207 had returned to its stable state, the potential at R20i is positive and greater than the negative going edge of the trigger signal, and this cannot pass through diode D 201. In contrast to this, the negative running edge of the end of the signal from MS 207 is fed to capacitance C202, and this negative signal can now pass through diode D 202 because the potential of the common terminal of R 202, C202 and D 202 at the end of the signal of the trigger circuit? 46 has returned to zero. In this case, MS 209 toggles and actuates HV2 in the same way as before, which at the end of a certain time sends out a stimulus via MS 246. It is understandable that the time constants of HVi and HV2 are different and that the irritation e.g. B. occurs earlier for HVi and later for HV2 It is also understandable that, as with HVa, the resistors R and R 'can be adjusted via potentiometers in such a way that adjustable response times are obtained, for example as a function of the patient.

Of course, it is possible to set the trigger circuit 24fi by some other arrangement for detection to replace the length of the sampled QRS wave, which emits a rectangular pulse which, as you can see: I am who Length of the QRS wave. To determine the additional systoles with a positive and a negative Point along its entire length it is z. B. possible, parallel to the trigger circuit 246 a second trigger circuit to place that responds to a negative potential and a signal with the same polarity below the Condition provides that a device is connected to the output of each of the two trigger circuits which makes it possible to extend the signal of each of the two Triggered circuits so something that in both Cases a continuous square wave signal is delivered, although the wave originating from the heart passes through through an intermediate point with zero potential-

goes

Of course, it is possible in the device according to FIG. 10 to omit the device HV2 and associated elements, if necessary, if it is assumed that in the case of sinusoidal systole it is unnecessary to have a variable waiting time Vzu.

In the third variant now described (FIGS. 12, 13 and 14), the capacity of the time delay devices is used simultaneously for the time base, and the charging resistor R 11 of this capacity is common to the time base and the means for changing the state of the time delay devices when the potential occurs .

It can be seen that the device has a heart detector electrode 101, the line of which is led to the input of an AND gate ET100, the second input of which is connected to a monostable circuit MS 101 (which are regulated between 300 and 400 ms, the gate £ T100 For example, it is blocked for 300 ms. During this period, no signal received at 101 can reach the device.
After this time, the return of MS101 to the stable state via line 103 again opens gate 7100 and tilts MS 102 back into the unstable state, whereby gate 7102 is opened during the time specified by MS102. If at this point a

If the extra systole SS detected via 101 occurs, the corresponding pulse passes through ET 101 and ET 102, which is now open, and arrives at FF101, which is tilted, as can be seen from FIG. 14. This tilting is detected by the line 111, which by actuating the transistors Q3 and Q4 causes the capacitance C3 to be discharged not suddenly this time, but instead slowly via the potentiometer P20. The capacitor thus discharges

; ncs! abi slowly how to get out of the falling phase of

len circuit with lead 102 to an electrode Irritation of the heart is associated. The one-shot circuit MS101 is equally wired

103 is connected to a monostable circuit MS 102, which can be regulated between 300 and 600 ms, for example, with AfS 1Ö2 being excited for the time corresponding to the return of MS 101 to its stable state. One of the outputs from MS 102 is on a line

104 connected to gate £ T102. The output 106 of the gate £ T102 enables the Kipper, a flip-flop circuit FF100, the output 107 of which is connected via a signal shaping circuit 108 (which in particular contains the transistor Q 16) to send a signal to the rhythm generator 110, which is described in more detail below is described.

Coming from the circuit 108 via the line 109 pulses provide the abrupt discharge of the capacitance d ^ s Rh ^v th nus ^|! € ⁷ neretors 110. On the other hand, the output 107 of the flip-flop circuit via a branch 111 at the same time with a barrier transistor device connected to the transistor Q 3 and with an opening device to the transistor Q 4. The rhythm generator 110 is connected, on the one hand, via an output 112 to a signal-shaping device 113, which transmits stimulus pulses emanating from the rhythm generator UO to the stimulus electrode. On the other hand, an output conductor 114 of the rhythm generator 110, which is connected to the potential of the capacitor of the rhythm generator, is connected via an impedance matching circuit 115 with the transistors Q 5, Q 6 to a Schmitt trigger circuit 116, which is connected to an input 118 of the Rip-flop circuit FF101 is connected. A diode 119 inserted into the line 118 enables the flip-flop FF 100 to respond (to toggle) only to the falling edge of the trigger signal.

As can be seen in particular from Fi g. 13 detects the capacitor C3 of the rhythm generator charges when no pulse appears on the line 101, and this capacitor takes after a certain time, the z. B. in the present example is set to 800 ms a potential that controls the programmable unijunction transistor PUT of the generator in order to trigger the sudden discharge of the capacitance and the transmission of a stimulus pulse to the line 102 at the same time. The transmission of this stimulus pulse causes the preliminary tilting of MS 101 into the unstable state via line 102, in such a way that matic curve can be seen which represents the course of the potential of the time base.

On the other hand, any increase in the potential of the capacitance CZ causes the Schmitt trigger circuit 116 to flip when the capacitance reaches a sufficient potential, which e.g. B. corresponds to a charge of 250 ms, as can be seen from FIG. This trigger circuit switches back to the initial state when the sudden discharge of the capacitance Ci occurs at the end of the predetermined period of 800 ms, if no spontaneous systole was detected. On the other hand, the Schmitt trigger circuit reaches the starting position in the same way when discharging via the potentiometer .P 20 when the potential of the capacitance C3 has dropped to a predetermined value. The falling edge of the Schmitt trigger circuit 116 occurring via 117 thus toggles the flip-flop FF100, and the corresponding signal at the output 107 is transmitted via 108 to the time base 110 at this point, the capacity of which is suddenly discharged from the residual potential. If this capacitance is slowly discharged, the trigger circuit controls the sudden discharge of the residual potential contained in the capacitance and the delivery of a corresponding stimulus pulse via 113 and 102.

At this point in time, the stimulus pulse received at 102 again causes the gate £ 7100 to be blocked via MS 101, and a new waiting cycle begins. It is easy to understand that the charging potential of the capacitance C3 is the smaller, and that the breakdown potential of the Schmitt trigger circuit during discharge is reached all the faster, the earlier the spontaneous systole occurs. The response of the device described takes place therefore faster so the earlier the spontaneous systole occurs It is clear that, by suitably changing the charging resistor Λ 11 and of the discharging resistor P 20 at the same time the stimulation period in the shared state, that is independent of the influence of the Systoien and the rate of discharge through the potentiometer P 20 can change.

According to another feature, the device can be designed to delay the waiting time, on the other hand, if the spontaneous sysiols do not occur prematurely, but appear somewhat before the normal occurrence of a renewed stimulus (if a spontaneous systole is not detected). It should be noted that this effect can be achieved for a first time by simply changing the charging resistance All and the discharging resistance P 20 of the capacitance C 3

can be achieved in such a way that when a pulse is a dangerous systole occurs right at the end of the dangerous period (just before closing £ 7102), the discharge the knockout potential of the trigger circuit reached after a duration equal to the normal period of 800 ms in the enabled state.

According to this other M (.r. <Times preferably a gate £ 7103, which is connected on the one hand to the output 105 of £ 7100 and on the other hand to an output of MS 102, which blocks this gate during the opening time of £ 7102. If this gate £ 7102 is blocked once, ie after the return of MS 102 to the stable state, the gate £ 7103 opens, and if a spontaneous delayed systole SS occurs, it runs through the gate £ 7103, the output of which is 120 with a Switch K 100. In the one position shown in Fig. 12, a corresponding pulse runs to a gate OU 100 and goes to a transistor Q2 to reset the time constant to zero (reference number 121 in Fig. 12).

As can be seen from FIG. 14, actuation of 121 causes the rhythm generator to be reset to zero, but this time without the simultaneous transmission of a stimulus impulse to line 102. From this it follows that after the occurrence of such a spontaneous, not premature systole, the capacity is renewed loads and the waiting time begins for 800 ms, unless a new spontaneous systole occurs.

By switching K 100 to the second position, instead of being sent directly to gate OU 100, the li.ipuls is sent via a line 122 to an adjustable monostable circuit MS 103 that can be varied between 50 and 150 ms, for example Holds the potential of the capacitance of 110 at NuH for the corresponding duration between 50 and 150 ms, specifically with the aid of the line 123 via the gate OU 100. In the latter case, the waiting time after a spontaneous delayed pulse is greater than the predetermined period of 800 ms and is z. B. equal to 950 ms when MS 103 is set to 150 ms.

According to another feature of the invention, the line 105 again has a branch which is connected to a gate £ 7104, the second input of which is connected via the line 124 to the flip-flop FF100, the output 125 of this gate also being connected to OU 100 is. This gate £ "7104 is only switched through via 124 if the flip-flop circuit FF100 has previously been toggled into its abnormal state, i.e. if a pulse of a spontaneous dangerous systole had already passed gate £ 7102 beforehand Gate £ 7104 remains open until the trigger circuit 116 has flipped FFlOO back into the initial state, as shown above. If during this time a new spontaneous systole immediately following a predetermined spontaneous systole appears at £ 7100 and through £ 7100 runs through it, a corresponding pulse goes through the gate £ 7104 and arrives at 121 via OU 100, which makes the potential of the capacitance C3 to zero without again emitting an artificial stimulus that the spontaneous systoles follow one another with a faster rhythm than the response of the device to the discharge via P 20.

However, it is also possible to additionally provide a setting of the potentiometer P 20 by hand, which makes it possible to change the discharge rate and thus the waiting time after a dangerous systole, wherein an automatic device for example, is applied to P 20 to the speed of the discharge in s increase in the event that the sequence of several dangerous systoles continues. It is thus possible, for example, to use an additional capacity which enables the time to be measured via the charging potential that separates two consecutive spontaneous systo-IPs, the charging potential achieved in this capacity being transferred to an electronic device for changing P accordingly 20 acts. In this case, P 20 is preferably replaced by several different resistors connected in parallel, the activation of which is controlled by electronic blocking devices, for example with transistors. In the same way, means can be provided for adjusting the value of P 20 to its initial value at the end of a certain time, when the sequence of dangerous systoles has ceased.

In one variant, it is equally possible to use instead of sending a single stimulus pulse to send out two successive stimulus impulses after the discharge of C3, in an automatic manner with the aid of a pulse generator controlled in a suitable manner by the device 110.

Finally, it is equally possible to adjust the intensity of the stimulus impulses as a function of the speed of response to change the stimulus device according to the invention. So the intensity of the stimulation remains or irritation constant during normal and regular operation without the occurrence of spontaneous systoles. On the other hand, in the case of the occurrence of extra systoles, this intensity increases in accordance with the increase in the Speed of response of the device, d. H. in relation to the premature nature of the extra systoles.

This relationship can be obtained in practice by placing between the stimulus source and the device 110 an electronic device is switched on, which increases the intensity of the stimulus pulses when the charging potential reached when a systole occurs decreases, d. H. when the systole SS is premature

In addition, the various devices can be combined with a blood pressure detector device which, when the blood pressure builds up more slowly, increases the stimulus intensity in the same way enables.

The device described may further comprise various elements or suitable derivatives, such as e.g. B. a connection 120a at the output 120 for counting the delayed extra systoles SS or the output 108 of £ 7102 can have a connection 106 for counting the dangerous extra systoles. These different outputs can be used in particular in connection with a device for changing the frequency of the rhythm generator, as was described in particular in the case of the first exemplary embodiments.

It can be seen that the device described can be implanted in an advantageous manner because it comprises a very small number of electronic units and has only a low energy consumption. Finally, the monostable circuits MS101, MS102 and / or MS 103 can be replaced by other devices , which allow the temporary blocking of the gates, these devices even being controlled directly via programmable transistors from the potential of the capacitance C3 of the device 110.

can be made.

Finally, the devices described can have a second capacitance analogous to CZ , but this is connected to a suitable device at the output of the ET 102 gate so that charging via a charging resistor only begins when a dangerous systole pulse passes through the ETX02 gate. If after this systole a new systole immediately following appears at £ T102, this capacity is discharged via a discharge resistor in order to trigger an irritation after the potential has dropped to a specified low value. If a second systole does not occur, the capacity discharges suddenly without causing irritation.

C) Other embodiments

As an example, the following other Ausführun ^cf sniö ^{t T!} Ichkc! Tcn described. A? first*? The embodiment enables a discontinuous change in the waiting time Y, which can assume two values, one being equal to the value of the stimulus period X and the other being smaller than X , this smaller value of Y being set for the most approximate systole. This embodiment is shown in FIG

This figure shows a device which has a detector line 8 connected to a first AND gate £ T301, a branch 321 from line 8 being connected to a second AND gate £ T302 and the output of £ T301 and the of FT302 is connected to an OR gate OU 300, which is connected to a pulse generator A 300 forming the time base, which normally generates the interval by a given period, e.g. B. 900 ms provides separate stimulus pulses. This is achieved with the help of a line 326, which controls a connected to the stimulus line 11 power stage P300 750 ms after each stimulus on the line 11 blocks During this 75C ais, MS 320 opens the gate £ T302 via a line 312, which is blocked via MS 301 when it returns to its stable state after 750 ms. A second branch 313 goes from 11 which leads to a monostable circuit MS 302 , which blocks £ T302 during the first 400 ms following a stimulation over 11 during the first stimulation pulse / after the transmission of a stimulus / the gate £ 7301 is blocked for 750 ms, and the gate £ T302 is blocked for 400 ms, opened during the following 350 ms and blocked again during the last 150 ms of the specified period of 900 ms. The output of £ T302 is different ts is connected to a time delay circuit P 300, which, when a signal passes through ET302 , sends a pulse or a signal to control P 300 at its correct output 315. A branch 316 from line 315 leads to gate OU 300 a line 325 can be provided, which leads from the line 8 to the control line 310 of MS 320, and a second line 327 can be provided for the same purpose at MS 302.

The mode of operation is as follows: If after a stimulus / systole SS occurs during the first 400 ms, the device shows no reaction. If SS occurs between 400 and 750 ms, the gate £ T302 is open, and the signal resets the time base A 300 to NuIi via OU 300, which is preferably a time base that is formed from a capacitor that charges Mch and that changes after a of a certain potential value suddenly discharges and S 300 controls the entire 900 ms. Such a time base corresponds to that already described above.

At the same time, the electrical signal originating from £ T302 reaches P 300, which after a delay time of z. B. 600 ms sends a signal to 315 and

ίο causes a stimulus / on the U line. At the same time, the time base A 300 is reset to zero via 316.

If a new spontaneous systole occurs before P 300 was able to pan control, ie before the end of the delay time of 600 ms, this second spontaneous systole goes through the gate J5T3O2, which is always open, and sets A 300 back to zero by it triggers P 300 again for the waiting time of 600 ms.

Device P300 can be a 600 ms monostable circuit. Thus, the device P 300 can not be effective if a second spontaneous systole before 600 ms occurs, after it has been actuated by a first spontaneous systole, B, a suitable device, such. B. have a flip-flop circuit which makes it possible to block the monostable circuit for 600 ms via a blocking transistor. This flip-flop can be brought to a first state by the first spontaneous systole, which enables the operation of the monostable 600 ms circuit of 5300, but which is switched when a second spontaneous systole occurs via the gate £ T302 to lock 5300. The stimulation flips the flip-flop back into its non-blocking state. Of course, instead of a single monostable circuit of 600 ms, the device J33OO can have, for example, a number of monostable circuits, a number of gates, such as £ T302, being provided which are successively but each opened individually, for example with the aid of the monostable circuits, such as MS 301, MS 302, which are triggered by the stimulus pulse. If a spontaneous systole occurs, it is passed in this way through the switch arrangement to the monostable delay circuit which corresponds to the AND gate, which is open at that moment Examples can be developed.

so in fig. 16 shows an embodiment using digital means

This device basically has a pulse source, a counter and a storage means which, depending on the number of pulses counted during the time K, controls the waiting time Y before the stimulation

As can be seen from FIG. 16, the detector line 8 is connected to a flip-flop FF 400, which is flipped by this line and which can be tilted back again via a stimulus line 411, the stimulus line 411 controlling a power stage P 400 for the pulses the stimulus line 11 emits The device comprises an up / down counter C 400, which can be alternately brought into the counting wire countdown state via the lines 401 and 402 according to the position of the flip-flop FF 400. The flip-flop forms the storage means for the number of pulses counted, as can be seen below. The apparatus includes a time base 414 which is contained in the

Practice is a pulse generator that supplies pulses with a fixed frequency to the up / down counter C 400. Such pulse generators are good belt ..,. Int. During the predetermined fixed period X of 1000 ms, for example, 414 sends out one hundred pulses, that is, one pulse every 10 ms. In this embodiment, the pulse generator 414 is never stopped. The mode of action is thus as follows:

A stimulus / is delivered to 11. The counter

pulse generator 414, the state of the delay means being the number of pulses counted.

Description of the device C

The device A of the pacemaker type, which allows the change of the waiting time Y according to the needs and needs of the heart muscle et-

- - c-o possible, can advantageously with a device

C400 is in the counting position. It counts all it io device C are connected, which allows a change of the Frevon 414 supplied pulses and is after a hundred quenz if necessary.

counted pulses are reset to zero, as in this case a periodic counting of a counter

Up-down counting is common, and sends out a number of impulses determined with the aid of the electrodes 2, which cause the stimulation via 411, and th cardiac systoles, for example out of 12 cardiac systoles, the same cycle starts again. If now a 15 (whereby this is all systoles, regardless of whether of spontaneous spontaneous systole occurs via the line 8, before one type or one hundred impulses caused by the stimulation are counted, this systole is FF 400), and as well as during the Counting of this pre-set state which, via 402, brings the counter C400 to the specified number of systoles to count a pre-set countdown state. From this moment on, benen pulls. Significantly smaller or at most equal to the number of spontaneous systocules assumed to be dangerous up to the point at which FF 400 tipped over, counted the number of further impulses that were supplied to him over 414 times, for example from premature extra systoles. If, for example, this spontaneous systole occurs at this predetermined number of dangerous systoles at 600 ms, the counter has 60 pulses, for example, is set to four. If one of these counts and now counts all new impulses until it is counted at zero term, the frequency of the series arrives. At this point in time, C400 controls P 400. the heart rate is temporarily increased, ie X sends out a stimulus pulse. It is understandable that in is being reduced in size.

"This device C can either be used alone or in

Connection to the device A can be used. The connection with A is preferred because in this case the device C does not have to have any detector means and no means enabling the selection of the spontaneous systoles to be counted as dangerous, the latter systoles of the device C directly via the selection gate, such as ET2, ET02

Examples have been described and, for example, 35 of the devices A already described are supplied by monostatic circuits or also by counters. On the other hand, if the device C may comprise independently opened gates. gig works, it increases the heart rate

In a further variant of the device, if it is possible for a predetermined number of times, it is possible to use a waiting time Y that differs from the systole, for example twelve or four dangerous systole interval K , from which it counted. If, on the other hand, she was together with a Vorfen. In this variant, if a second pulse direction A is operated, the dangerous synerators 412 of a known type are provided. These impulses for the most part due to the variable pulse generator 412 can deliver pulses to C400, if the waiting time Y is eliminated, and only if, for example, one hundred pulses in 1000 ms, but device A does not suppress these pulses 45 occurrence of dangerous extra systoles is sufficient, such as a generator 414, but on the contrary, and if the device C is temporarily increasing the rate for this, is effective from uniformly decreasing intervals, for example during a period of being separated. For example, 412 delivers four pulses during the 10-20 seconds, the frequency is now from a free first 100 ms of its operation, during a frequency of 60 pulses per minute on the frequency of the following 100 ms five, etc. The mode of action is 50 of 90 Increased pulse beats per minute It is understandable that the counter C400 counts the number given to it by 414, that this frequency increase is given as an example and that it is equally possible to provide a device C in which the temporary increase in frequency takes place in several stages , whereby

At the same time, FF400 prevents the frequency from being set up for a certain period of time Established lines that pulses from 414 to C400 are increased to 60-80 beats per minute and when

this is insufficient to 80-100, etc.

In the special embodiment described below, the waiting time Y is no longer registered, it needs to be changed for counting starting from 60, if C stimulates with its increased frequency 412 a longer time When all pulses have been counted, the stimulation emanating from C is suppressed the journey

In this case the waiting time Y is exactly equal to the interval A , ie 100 ms in the given example. C 400 tilts at the same time as the control of P 400 FF 400 so that it is reset to the counting state itself.

Of course, the device can have various sampling and selection means for the systoles, which occur at 8, whereby these remedies can be identical or similar to those already used in the earlier

led impulses and is, as described above, under the influence of spontaneous systole, which is the tilting of FF400 causes the countdown to be returned

gen, and starts the pulse generator 412, and the counter again counts the impulses that are fed to it. If z. B. C 400 60 pulses from 414

the stimulation occurs and the flip-flop is flipped back again, ie 414 sends out new impulses to C 400.

In this variant, the time delay means consist of the counter C400 and the pulse generator 412, and the flip-flop and the means for changing the State consist of the counter C400 and the im-

tion that starts from A.

The detector line 8 enters the systole after it has been fed to the device A to the device C, which allows the temporary change in the frequency of stimulation of the heart in the case of occurrence of spontaneous dangerous extra systoles In the device C, the line 8 is a Integration

circuit 512 led by one under the name Step integrator known type is this integrator supplies a discontinuously increasing potential in steps, with each pulse coming from the line 8 the potential of the integrator increases by one level. After the twelfth stage, i.e. H. after the twelfth systole the potential of the integrator is automatically reset to the initial value, and at the same time the Integrator emits a zero reset pulse via line 513, the course of which is described below. This integrator 512 forms the counter for the systoles, which are either spontaneous or excited systoles can.

Another line 514 originating from device A arrives at device C. Via this line 514 only impulses are carried which correspond to premature, spontaneous cardiac systoles which are to be regarded as dangerous. The device A selects only impulses from dangerous premature spontaneous systoles via the line 514 with the help of an opening of one of the gates such as £ T2 or £ T02 (which are opened, for example, for 400-750 ms after a slekirosystoie ES). The line 514 is led to an AND gate £ T4, the second input 515 of which is connected to an output of a flip-flop FF 4, the line 515 normally switching the gate ETA through when the flip-flop FFA is in the appropriate state . The gate ETA is connected to a counter 516 which is shown in FIG. 2 is shown within dashed lines, the counter 516, which counts the dangerous premature spontaneous systoles, for example two flip-flop circuits FF2 and FFZ and a decoder DD , the mode of operation of which is explained below. The decoder has four outputs, which are connected to a switch K 10 with several positions, whereby the switch can be operated manually or automatically or also via any remote control method when the device is implanted in the patient's organism The switch K 10 is connected via a line 517 to one of the inputs of the flip-flop FFA . The output 515 of the flip-flop FFA is likewise connected to two blocking transistors A 10 and A 20. The blocking transistor A 20 prevents the operation of a time base, for example an integrator 15, when the flip-flop FFA is in its normal state, the integrator integrating a potential in the enabled state for a period of 15 seconds, whereupon its potential is raised the initial state drops back and it emits a pulse via an output line 519

In the normal state of the flip-flop circuit FFA, the blocking transistor A 10 prevents the operation of an integrator 520 which, as a pulse generator, supplies pulses with a predetermined frequency to the line 511, these stimulus pulses controlling the power stage 10 for each pulse received over 11 delivers a stimulus to the heart electrode. As can be seen from the drawing, the pulse generator 520 is preferably controllable, the output frequency between z. B. 90 and 150 pulses per minute is adjustable. It is equally possible to use a non-adjustable generator that only supplies a single frequency. In any case, the smallest rate provided by integrator 520 may be greater than the pacing rate of pacemaker A or of all of the other cardiac pacing device connected to device C.

The operation of the device C is as follows:
The integrator 512 is in the initial state, its potential increases by one step with each pulse coming from the line 8 and caused by a systole, which can be either a spontaneous systole SS or an artificial systole ES , and which is determined with the aid of the electrode 2 . At the end of the twelfth counted systole, the integrator 512 resets itself to its starting position and sends a pulse via a ίο line 513, which runs via a gate Oi / 20 and a pulse shaping circuit and resets the counter 516 for the premature spontaneous systoles to zero if a dangerous premature spontaneous systole occurs, it is normally counted in the integrator 512, but at the same time a pulse is passed on the line 514 to the gate ETA and this pulse is counted in the counter 516 for the premature spontaneous systoles. In this case, Assuming that the frequency of the artificial cardiac stimulation should only be increased if at least four premature spontaneous systoias occur during a cycle of twelve systoles, the switch K 10 is set to position 4 and the counter 516 only then sends a pulse to 517 if it was able to count four pulses from 514 on line 513 before resetting to zero. Thus, 512 counts all cardiac systoles, while 516 only counts the dangerous spontaneous systoles, for example those which have passed the gate ET2 when the device A of FIG. 3 corresponds
Of course, the counter 516 for counting the premature spontaneous systoles can also have a different number of outputs instead of the four outputs. In Fig. 2, the changeover switch K 10 is in a position in which it is connected to output 1, which means that a pulse is transmitted to FFA via 517 when a pulse reaches device 516 via gate ETA. The mode of operation in this position, in which the counter counts only a single pulse, generally does not correspond to the normal mode of operation of the device, because in this case the device C temporarily increases the stimulation rate if a single spontaneous premature systole occurs.

When the counter 516 for the premature spontaneous systoles has counted the intended number of spontaneous premature systoles before it was reset to zero by the fall of the integrator 512, a pulse is supplied to the output 517 of the counter 516 in order to the flip-flop FFA Tilt. By leaving its normal state, the flip-flop makes the transistors A 10 and A 20 conductive via its output 515 in such a way that the time base 518 and the pulse generator 52C are put into operation, the generator 520, as mentioned above, transmitting the desired Heart stimulation pulses to the heart electrodes 2 controls. During this time, the second output 521 of the flip-flop FFA acts on a blocking transistor A 30 of the integrator 512, which is reset to its initial potential and is held in this state as long as FFA remains in the toggled state. After 15 seconds, the potential of the integrator 518 drops, and the integrator sends a pulse over the line 519, this pulse: via the gate OU 20 on the one hand to the counter 516, which is thereby reset to zero, and on the other hand: with the help of a Line 522 is fed to the second input of the flip-flop FFA , which is thereby tilted and returns to its normal state, whereby the integrator 518 and the pulse generator 520 are stopped and the cardiac stimulation via this Zcitbasi:

is canceled and at the same time the integrator 512 is released, so that the device B again returns to the waiting state for the detection and counting of impulses inhibiting dangerous premature spontaneous systoles, as was the case above.

In particular, it can be seen from FIG. 18 that the counter 516 for the premature spontaneous systoles also includes the gate ETA and the two flip- flops FF2 and FFZ, which are each connected to four AND gates ET5, ET6, ET7 and ET8 , the four outputs of which are correspondingly connected to the four contacts of the switch KlO. This type of decoder is already well known and it should therefore not be necessary to describe in detail how it works.

As shown in FIG. 3 to detect the operation of this meter is as follows: The flip-flop FFI is tilted by the falling edge of the next from the gate ETA electrical systole, when the counter was 516 previously geschähet on NUII and the first pulse on ETA is running, this pulse passed to the gate ET5 , which it can pass through because the other two inputs of this gate £ T5 are switched through to the corresponding outputs of FF2 and FF3 , both of which have a positive potential. The three other gates of the counter 516 are opposed locked on this because at least one of its inputs is not switched Therefore the pulse passes through the gate ETS and arrives to the terminal no. 1 of the switch K 10. When the switch is connected to this terminal, If, on the other hand, the changeover switch is connected to terminal no. 4 of K 10, no pulse passes through line 517, and the only change in the device would be to flip the FFZ. If a second dangerous systole now occurs, the falling edge flips FFI and brings it back to the initial state. During this process, the negative tendril flips FF3, which is set so that it responds to the negative edge of FF2. At this point in time the gate £ T6 is switched through. As soon as the pulse has passed through the gate £ T6, this gate is blocked by toggling FF3 , and now the gate £ T7 is switched through for the passage of a third premature spontaneous systole that occurs. If a fourth premature systole occurs before the entire arrangement 516 is reset to zero by the integrator 512, this latter is passed via ETS because this was switched through at the end of the previous pulse by tilting FF2 , where K 10 is in position 4, and a pulse is sent to FFA if the four pulses have been selected by then.

It will be understood that the counter 516 for the premature spontaneous systoles can also be constructed in a different manner and that it is not necessary to be able to change the predetermined number of the premature spontaneous systoles to be counted in order to act on FFA . This number can be determined in advance, particularly in the case in which the device for stimulating the heart is implanted.

On the other hand, it is possible to provide a switch-off push button K 3 in device B , which can connect a line 528 to ground which - when connected to ground - brings the flip-flops FF2, FF3 and FFA to their initial state. It is thus possible to reset the pulse generator 520 to zero if it was previously in operation without waiting for the integrator 518 to drop. The actuation of the push button K 3 consequently restores the entire arrangement B to its initial state.
In contrast to this, a second push-button switch K 2 enables the input of the flip-flop FFA to be acted on in the same way as if it were activated by one of. the pulse coming on line 517 would be actuated. This push-button switch K 2 makes it possible to start the pulse generator 520 without this

ίο Wait for dangerous premature spontaneous systole to occur. In the case of a planted device, the contact K 2 can be closed, for example, by a remote control.
Finally, a double contact KA can make it possible either to open the blocking circuit of transistor A 10 and to connect line 528 to ground or, on the contrary, to leave the blocking circuit closed and to disconnect line 528 from ground. In the first case, the contact KA enables continuous operation of the pulse generator 520, which can essentially consist of a programmable unijunction transistor PUT , the remaining part of the device B being kept in the quiescent state by connecting the line 528 to ground. The device such as C can also be used to make the time delay means effective only if a given number, e.g. two, of dangerous systoles SS are detected during the predetermined number of 512 counted systoles (e.g. 12 systoles). In this case, FFA is not connected to the time base 520, but rather to an element which brings about the predefined waiting time X if no two dangerous systoles 55 have been counted in 516. In this case, the first dangerous systole SS is followed by a waiting time which is equal to X , the second dangerous systole 55 being followed by a waiting time V.

Reference is made to FIGS. 19, 20 and 21 below.
In one embodiment, various parameters of the response of the device A or B Vorrichung can be controlled by a device which is responsive to the pressure intramyocardischen Thus, the intensity of the stimulus pulses / or the period X, or the ratio Y / K automatically according to the

Change in intramyocardial pressure.

The change in intramyocardial pressure is not understood as the sudden change in cardiac systoles, breathing or other organic movements

caused changes, but in contrast to this the change in the mean base pressure, for example, during the resting period of the heart muscle is measured. This change, if it takes place at all, is very slow and can in certain cases Cases can only be detected over the course of several hours.

This arrangement for determining the intramyocardial pressure is characterized in that it includes a micro-pressure detector, a liquid at least partially surrounding this micro-detector, such as. 3. Polyvinyl pyrolidone, a soft envelope containing the liquid and one or more lines, preferably electrical lines, which connect the micro-detector to the device A , comprises.

The micro-detector can be of a type already known, which is described in more detail below as an example will.

The casing can either be made of a fine-machined

gen fabric made of very thin and soft threads, for example made of glass, metal or plastic material fabric, or of a thin, either porous or impermeable membrane, for example made of an elastomer or plastic material. By doing In the case in which the covering consists of a fabric or a non-dense membrane, one need not be Moisturizing liquid that does not tend to get into the envelope or into the surrounding organic material to diffuse.

The device according to the invention enables the determination or measurement of the intramyocardial pressure and is preferably arranged at a junction 601 of an intraventricular catheter 602. This intraventricular catheter 602 carries two electrodes 603 and 604, which normally enable the cardiac stimulation. The junction 601 can in the same way have an electrode 605 which interacts with the electrode 602 and which can be put into operation if it is determined that the electrode 603 is no longer effective because the stimuli are no longer followed by systole. The junction 601 penetrates the intraventricular septum 606 and comes out in the left ventricle 607 , for example. A blood pressure detector 608 can be attached to the end of the junction 601, for example. The catheter forming the junction 601 comprises, according to the invention, a detector 609 for the intramyocardial pressure, which consists of a micro-pressure detector 6JO, which is for example of the type sold by Societe Statham and is arranged inside rather liquid 611. A line 612 enables the The information from the desector 61 is supplied (/ along the catheter to the at least partially (not shown) implanted device. The liquid 611 is located in an extremely soft envelope 613.

It is also possible to prevent the build-up of a fibrous layer (couche de fibröse) around the envelope 613 by surrounding it with a layer of venous or connective tissue originating from the person who is being equipped with the device according to the invention. It is equally possible to create the sheath 613 by occluding a small piece of vein at both ends.

The pressure detector 609 can be put in place in the intraventricularen septum characterized by, for example, employs a catheter having an outer tube 614, the end 613, the tip 608 moves forward, when the peak was 608 once brought into the correct position, For example, inside the left ventricle 607, the outer tube 614 need only be retracted, with the inner junction 601 remaining in place. When it is desired to pull out later, the branch 601, so it is possible, where appropriate, reinforcing members 616, for example from metal thread to provide on the cladding 613 so as to become in the retraction of the branch 601 tensile forces arising without the risk of tearing the envelope 613 transfer. It is of course possible to arrange the casing 613 in a different manner with respect to the junction 601 without departing from the scope of the invention. Likewise, the intramyocardial pressure detection may be performed elsewhere than in the intraventricular septum, although the latter arrangement is preferred because the septum can be easily punctured without causing any damage to the heart muscle

In the following, with reference to FIGS. 22 and 23 describe an improvement of the device A in the form of the second preferred embodiment device, which, however, applies in the same way to the various other embodiments of the device according to the invention, as shown in particular by FIGS. 3.15 or 17 can be used.

ίο The device described below enables it occurs when a first spontaneous systole occurs, which is immediately followed by a second spontaneous systole If this second spontaneous systole occurs, a new waiting period should run, this time accordingly de; n method according to the invention is variable and is no longer specified as was the case with the devices described above.

This improvement is basically achieved by halving the time delay means in such a way that one of these time delay means allows a waiting time to elapse which, according to the method according to the invention, is variable when a first spontaneous systole occurs while the second time delay means change their state as a function of time to provide a new Wärtereit in the case of occurrence of a second spontaneous and directly following systole, which in turn is also correspondingly variable to the process according to the invention in the described apparatus, the latency or waiting durations Y are preferably smaller than the time intervals K, from which they are generated, in such a way that the devices can intervene very effectively with tendencies of the heart to adopt a tachycardiac rhythm.

In the description of the device that now follows, a variable waiting time is introduced for all spontaneous and directly successive systoles, although it is understandable that with the simpler devices it is only possible to run r ^: j> e variable additional waiting time after the second spontaneous systole let, with an optionally following third spontaneous systole the arrangement on a fixed waiting time, the z. B. is equal to X , brings back, as was the case with the devices already described above.

The in the F i g. 22 described device comprises in particular a gate connected to the detector line 8 £ T700, which can be blocked for a short period of time via a monostable circuit MS 701, which is activated via the stimulus line 11 in the event of the occurrence of stimulus pulses / to prevent that the systole caused by this stimulus can get into the device. A second monostable circuit MS 702 is provided to the gate for a period which z. B. is equal to 300 ms after the detection of a spontaneous or non-spontaneous systole. The output 701 of this gate is connected on the one hand to a device D 701 and on the other hand to a device D 702, these two devices representing the switch means and can be implemented, for example, in the form of a divider circuit that divides by two, as is well known in electronic technology is. If a spontaneous systole SS occurs, it runs via the gate £ T700, blocks this for a duration that is greater than the partial period specified by AfS 702 and then appears at D 701 and D 702. D 701 has two outputs 702 and 702

35 36

703, while D 702 has two outputs 704 and 705 a new spontaneous systole SS, like beschrieaufweist above, if a of 701 incoming pulse acts ben over, it means discharges the capacity of HV via D is guided to the line 702, 701, this is via its discharge resistor and causes the charge from D 702 to be conducted to line 705. It is connected to HV via D 702. A second spontaneous systole SS now appears

704 if he was on the other hand via 0701 to 70 $ 5 before the end of the waiting period from HV. This second was headed. The spontaneous-by-two Teilerschaltun- systole now runs one hand via 703 and gene D 701 and D 702 are also at the same time the other hand via 704. (not shown) When passing through about 703 beüber branches it acts from the Leitun- the discharge of HV 'on Entladewidergen 721 and 722 in the srtiert, if on one of these two stood by HV, whereby a new waiting time to run a stimulus pulse occurs / so the divider starts at the same time the pulse acts on the

ρ circuit D 701 when it receives a first pulse on 702 line 713 briefly on / 700 and discharges very much

'has automatically adjusted so that it quickly increases the capacity of HV, which immediately resumes with the

delivers the following impulse to 703 If, however, a stimulus charge begins The impulse that runs otherwise to 704,

impulse / an 721 appears before a second spontaneous one has no effect because FF701 is already in the non-

Systole, which should be directed to 703, appears is 15 locking state was tilted by HV. If no-

D 701 is reset to its initial state and the third spontaneous systole occurs causes the end of the

The following spontaneous systole runs over 702. Discharge of HV ' an irritation /, as from FIG. 23 to

The lines 702 and 703 are each marked with two priorities. At the same time, D 701 and D 702 are connected to directions HV, HV , which are mutually and reset to a state by setting the path in, for example, with the detailed in FIG. 8 open the direction to 703 and 704 because their state th device HVa are identical. If a pulse has changed to when the second systole SS occurs. 702 appears it causes the discharge of HY via So HV now continues the stimulation with the given discharge resistance, and at the end of this Eotla period it is assumed that after one of these changes, HV delivers a stimulus pulse via 721 to the conductive stimulation ( Right part of FIG. 23) a new voltage stage P 700, which amplifies this impulse and occurs at 25 tane system SS. At this point in time it runs the stimulus line 11 passes on as already described via 703, and HV discharges through his Was unloading. The same applies to HV when there is an impulse. A new spontaneous systole SS appears before a spontaneous systole above 703. By the way, at the end of this discharge, and the corresponding ini can the devices // V and // V via blocking pulse now runs via 702, and HV, the previously charged sistoren / 700 and / '700 are blocked, & h, the Po- 30 is now discharging through its discharge resistance, the potential of the capacitance is kept at zero, whereby the during HV suddenly changes over the branching transistors for a short time under the influence of the blocking transistors. Impulse discharges which appears via 712 at the blocking circuit gen 713 and 712 from lines 703 and 702 or / '700 // V begins to charge again immediately, for a longer time via the flip-flop FF701 A third spontaneous systole appears before the end the or FF 702 are actuated, which in the blocking state 35 discharge of HV, and HV discharges are now suddenly switched via stimulus impulses, which in the first case would be via the impulse running through 713 nd the pulse HV running via line 722 via 724 and, in the second case, from 703 via its discharge resistor line 721 via 723. stood until irritation / discharged

These flip-flops FF701 and FF702 can be It is thus understandable that the tachycar

Lines 704 respectively 705 in the non-blocking services can be effectively combated by Y so

stood to be tilted back. The mode of action is set in such a way that it is constantly smaller than K of

with the following: to which it was caused.

Assuming that - as shown in FIG. On the other hand, it can be seen that the device

ncr. is - FF 702 HV blocks "" HV will not be realized by any other way according to Fig. 22

FF 701 blocked If no spontaneous systole occurs 45 can.

HV excites with the given period X, and there are

two successive stimulation impulses / in the left one 15 sheets of drawings

Half of Fig. 23 to recognize. Now occurs a spontaneous one

Systole SS up. It appears on D 701 and becomes on 702

so that the capacity of HV via the discharge 50
resistance is discharged. The waiting time starts at
At the same time, D 701 703 switches on and blocks 702 for
any subsequent spontaneous systole. If at the same time a pulse over 702

was led, D 702 leads the 55 coming from 701
The pulse to 705, FF702 is flipped again and the blocking of HV is ended. The capacity of HV begins
to load yourself. If there is no second spontaneous systole on
End of discharge occurs irritates HV by causing a

Stimulation impulse emits, This stimulation impulse /, which is sent to 721
seems before it goes over 11, flips over 723 FF702
in the blocking state for HV. At the same time occurs
via a junction (not shown) from 721 der
Pulse / D 701 and D 702 delivered via HV into the

Aniangsstatus returned in such a way that the turnout 65
reopened in the direction of 702 and 705
are. HV continues to stimulate with period X,
like this from F i e. 23 can be seen. It then appears

Claims (18)

Patent claims: 1. Device for monitoring and controlling the human heart function, with one of electrodes connected detector for spontaneous electrical heart signals, furthermore with an electrode connected stimulation pulse generator for supplying electrical stimulation pulses to the heart and with a control device for the stimulus pulse generator, which the repetition frequency of the spontaneous electrical Heart signals are determined and the repetition rate of the stimulus pulses controls in such a way that the stimulus pulse generator Emits stimulus pulses with a predetermined first repetition rate when the Control device determined repetition rate of the spontaneous electrical cardiac signals a predetermined falls below the first limit value, and that the stimulus pulse generator stimulus pulses with a second Subsequent frequency yeasts by the predetermined first Repetition frequency deviates when the repetition frequency determined by the control device is spontaneous electrical cardiac signals exceed a higher second predetermined limit value, characterized in that during the delivery of stimulus pulses with the second repetition frequency the stimulation pulse repetition frequency of the repetition frequency then occurring spontaneous electrical Heart signals is independent and that the second repetition rate imni.T higher than the first repetition rate is 2. Apparatus according to claim 1, characterized in that the stimulus pulse generator inhibits QRS is. 3. Apparatus according to claim 1 or 2, characterized in that the second repetition frequency is higher as that repetition rate of the spontaneous electrical heart signals through which the delivery of the stimulus impulses was triggered with the second repetition rate is 4. Device according to one of claims 1 to 3, characterized in that the control device the repetition rate of the spontaneous electrical cardiac signals determined from at least one cardiac cycle in which at least the systole at the end of the cycle is spontaneous 5. Device according to one of the preceding claims, characterized in that the stimulus pulse generator Emits single pulses with the second repetition frequency. 6. Device according to one of claims 1 to 4, characterized in that the stimulus pulse generator a pulse train repeated at the second repetition frequency 7. Device according to one of the preceding claims, characterized in that the second Repetition frequency of the stimulus pulse or stimulus pulses is variable and with the frequency of the spontaneous electrical heart signals increases. 8. Apparatus according to claim 7, characterized in that the second repetition frequency is continuous is changeable. 9. Apparatus according to claim 1, characterized in that the second limit value, which is exceeded causes the delivery of stimulus pulses with the second repetition rate, between the single and double the value of the first repetition frequency. 10. Device according to one of the preceding claims, characterized in that the device Means (512, 516) for counting the spontaneous electrical cardiac signals and for triggering exhibits irritation when the count exceeds the second limit 11. The device according to claim 10, characterized in that the counting devices (512, 516) control the stimulation when they have a predetermined number of these spontaneous ones in direct succession counted electrical heart signals. 12. The apparatus of claim 10 or 11, characterized in that the control device the £ wide repetition rate gradually increased when it returns to the preset rate after stimulation The number of these spontaneous electrical heart signals counts 13. Device according to one of the preceding claims, characterized in that the control device Means for dividing the time elapsed after the occurrence of an electrical cardiac signal expires in at least two consecutive windows, each two different Values of the stimulation pulse rate are assigned, of which the higher is the second stimulation pulse rate Posed 14. Device according to one of claims 1 to 13, characterized in that the control device Has devices that respond continuously to the time elapsed between an electrical Heart signal and the subsequent heart signal, and the stimulation with a repetition rate control, which is continuously variable as a function of this time. 15. Device according to one of the preceding Claims, characterized in that the control device has circuits with one or more Capacitors includes. / Lie in. 'Depending on their charge or discharge, the repetition rate of the spontaneous electrical cardiac signal and the repetition rate determine the stimulus or stimulus impulses. 16. Device according to one of claims 1 to 15, characterized in that the control device has digital devices (C 400) for determining the repetition rate of the spontaneous electrical heart signals and the repetition rate of the stimulus pulse or stimulus pulses. 17. Device according to one of the preceding claims, characterized in that for loading : tuning of the exceeding of the second limit value by the repetition frequency of the spontaneous electrical Heart signals a circuit with AND gates is provided, which is connected to the detector is, the AND gates are operated in sequence. 18. Device according to one of the preceding claims, characterized in that devices for the identification and differentiation of cardiac signals of ventricular and auricular origin and devices (HVi, HV2) for determining the second repetition rate depending on the origin of the cardiac signals are provided, which the delivery of the Induce stimulation impulses.