DE2314315A1 - ATRIAL AND VENTRICAL PACEMAKER WITH INDEPENDENT FREQUENCY AND DELAY CONTROL - Google Patents

Description

PATENT Attorney P _{-1 BERL} | _{N 33} March 14, 1973 MANFREDMIEHE FALKENRIED 4

Telephone: (0311) 76MSO <8 3119 50> Chemist Telegrams: PATOCHEM BERLIN

AO-2525 US / 02/2069

23H315

AMERICAN OPTICAL CORPORATION Southbridge, Mass. 01550, USA

Atrial and ventricular pacemaker with independent Frequency and AV delay control

It becomes an atrial and ventricular pacemaker with independent rate and AV delay controls suggested. An adjustable one is used to control the frequency of the ventricular pacing pulses Timer circuit provided. The occurrence of each ventricular beat triggers an atrial pulse generator circuit off and an atrial pacing pulse is generated following a variable time interval. The ventricular rate control circuit has a potentiometer and the atrial pulse generator circuit has two potentiometers which are connected in series, one of which is synchronized with the ventricular Frequency potentiometer is coupled. When the impedance of the ventricular rate potentiometer increases for the purpose of increasing the ventricular pause interval, as a result of the synchronization of the two Potentiometer increases the atrial pulse delay equally. Thus the AV delay remains constant, even if the pacemaker rate is changed. The second potentiometer in the atrial Pulse circuit is used to change the AV delay.

The invention relates to atrial and ventricular on-demand pacemakers and particularly those pacemakers where the rate and AV delay controls are independent are from each other.

With atrial and ventricular pacemakers according to the state of the art, separate pulse generator circuits are provided,

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to stimulate pulses at corresponding predetermined time intervals following the last ventricular beat to create. The ventricular pause interval (the length of time between successive ventricular beats) is longer than the atrial pause interval (the time between successive ventricular and atrial beats) so that an atrial pacing pulse prior to a ventricular pacing pulse is produced. Every detected spontaneous ventricular beat controls the resetting of both pulse generator circuits.

In some prior art pacemakers, each of the pulse generator circuits are free running; corresponding atrial and ventricular pacing pulses are issued at set intervals in the absence of a reset of the pulser circuit generated. The pacemaker clock is with the natural heartbeats by means of controlling the reset the two circuits are synchronized when each ventricular beat is detected. Although systems of this Art have proven satisfactory in implantable pacemakers, a problem arose when the same are used in conjunction with external pacemakers, i.e., external pacemakers of the patient with the exception of the electrical lines.

In atrial and ventricular demand pacemakers, each of the pulser circuits has a potentiometer that can be set to set the corresponding pause interval. Since the pulse generator circuits do not exist of a reset pulse, it is evident that in the presence of an atrial pause interval of less than 50% of the ventricular pause interval, two or more atrial pacing pulses between each Pair of ventricular stimulation pulses generated v / ground. Detecting a ventricular beat or generating it

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a ventricular stimulation pulse leads to a reset 'of both pulse generator circuits. If the ventricular pause interval is N milliseconds and the atrial pause interval is less than N / 2 milliseconds because both pulser circuits are free, it is obvious that if a spontaneous ventricular beat is not detected before the ventricular interval has expired, at least two atrial pacing pulses will be generated. This is because atrial stimulation pulses are generated continuously at fixed time intervals when a spontaneous ventricular beat is not detected or a ventricular stimulation pulse is generated. Several atrial stimulation pulses can of course only lead to harmful effects, since the atrium should not be stimulated too quickly in response to a ventricular beat.

In the case of implantable cardiac pacemakers, in which the potentiometer settings are made during production and not changed, this problem is not so severe because satisfactory manufacturing processes can be used to ensure that a plurality of pacing pulses are not generated. In the case of an outside pacemaker, however, medical or clinical personnel adjust the various control buttons to change the two pause intervals. Particularly in the case of poorly trained personnel, the atrial pause interval can be set to less than 50% of the ventricular pause interval, which enables multiple atrial stimulations.

In the improved atrial and ventricular pacemaker according to the German patent specification (German patent application P 23 09 212.8), to which reference is made in this application, several atrial stimulations are excluded, even with very short atrial pause intervals. The heart chamber pulse generator is free running, as is the case with pacemakers according to the prior art. The Pro

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Hof imnulsgeberkreis is however ri ohr free running but rather has a monostable .dulrivibrator »Das Establishing a spontaneous cardiac shock or creating it a ventricle st imulierunr-'i. · 'ouises read an atrium clock circuit off. To ence des 7i. '± he set atrium oausenintervalis the 'Iurtrrrrrarcr is activated and it an atrial stimulation impulse -: r:, zaugt. Then return the multivibrator is back in its rest and as will no further atrial stimulate ::; ^: j3.irnpüiss generated, um induce a renewed triggering of the Mu] tlvirrr-.vurs, a new clock period must start r ^ .5 si ;, ^ t '- / earth ::, and this only takes place when the next cri ^ rcr'tare career. "- strike detected or the "äer ^ rr rrrrkarnverstrvulierungsimpuls is produced. Even if there:? , "crliofr ^ a asenintarvall set to less than 50% of the KerzkamirLe.rueiU'senintervalls the multivibrator is activated only once for each ventricular beat triggered. Thus rr -not possible: · that several Atrial stimulations between he ^ kirrre ^ erhlägr-r, occur.

. The ventricle pulse --7GiSt ^{^:} .r, ■■ c th; io: net.er to change the Herzkammerpausenint.errv-ΛΐΓ.ΐ λ: UUD pre yard pulse generator has a potentiometer :: - :::. __ "^ randirn of Vcrhofpausenintervalls on the lcrzter * v;.. -rv3.Il is the Take period between a ventricle so '· ... ow and the three subsequent ic'α VorhofstiFiulierungsinpu] ■> ind is considered in the following..? the VA interval denotes, va? interval between each atrial stimulation pulse and the subsequent ventricular stimulation pulse is known aJ.i- ^: ie AV stimulation. The term W interval, - as it is used here, also refers to as>;'. time interval between successive HerzkanmaerstiiT' / li-srung inpulsen in the pacemaker according to the above .- r.gogebener German patent application shows that ei-f vinreteilung of Herskammerimpulsgeber potentiometer niy?.... .:. t only controls the \ ⁿ 7 interval, but also the AV delay "If ? ,, B, das W-interval increases and the setting of the atrial inou is generator potentiometer is not changed - if the VA interval remains the same, the result is that the AV delay also increases. However, it is very often

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Require the W interval without changing the AV delay to change. In the case of the pacemaker according to the German patent application cited above, the doctor must After setting the pacemaker rate, it is necessary to also set the atrial pulse generator potentiometer, when he wishes to maintain the same AV delay.

It is an object of the invention to provide an atrial and ventricular pacemaker which has two independent controls for setting the pacemaker rate and the Av delay. With the pacemaker according to the invention, the doctor can adjust the pacemaker rate without the To influence the AV delay and / or he can adjust a setting for the purpose of changing the AV delay without influencing the pacemaker rate.

According to the invention, the ventricular pulse generator has a single Potentiometer on and the larger the impedance setting, the longer the W interval. The atrial pulse generator has two potentiometers connected in series and the greater the series impedance, the longer the VA interval. One of the atrial pulse generator potentiometers is synchronized with the ventricular pulse generator potentiometer. When the latter potentiometer is turned to increase its impedance, the one that is synchronized becomes Potentiometer in the atrial pulser rotated in the same way, increasing its impedance.

For example, suppose the doctor wants the W interval to be increased. By turning the shaft that couples the two potentiometers together in synchronism, the W-interval as a result of the increase in the impedance of the cardiac arrester potentiometer extended. At the same time, however, since the synchronously coupled atrial pulse generator potentiometer is rotated so that its impedance increases, the VA interval also increases. The two

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Synchronously coupled potentiometers have the same maximum impedances and act in such a way that the same impedance change for each potentiometer affects the VV interval or the VA interval to the same extent. Thus, if the W interval is increased by rotating the shaft? which couples both potentiometers in synchronism, the VA interval increases to the same extent. Since the AV delay is equal to the difference between the W-interval and the VA interval, the result is that the _f-V delay remains constant. To set the AV delay, it is only necessary to change the setting of the other (independent) potentiometer in the atrial pulse generator. This potentiometer only influences the VA interval and thus the AV delay can be set independently.

Another inventive feature is the provision of two potentiometers in the atrial pulse generator and of a potentiometer in deir Kerzkammeriinpiilsgeber, the insane Synchronization with one of the atrial pulse transmitter potentiometers is coupled.

An embodiment of the invention is shown in the drawings and is described in more detail below:

Fig. 1 is the same as FIG. 2 according to German patent application P 23 09 212.8 and represents an atrial and cardiac pacemaker in which the frequency and AV delay controls are not independent of one another.

Fig. 2 illustrates an exemplary embodiment of the subject matter of the invention with dsm independent frequency and AV delay settings can be made.

In the following, only the parts of the circuit according to FIG. 1 will be explained, which are future. Understanding. of the present invention are required. The pacemaker has a pair of electrodes E1 and E2, which the Herskammerstimulie-

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tion and the detection of a spontaneous heartbeat, uii · - a pair of electrodes E3 and E4, which stimulate the atrium serve on. A spontaneous ventricular beat leads to the appearance of a signal at the electrodes E1 and E2 and this signal is processed and results in a pulse that passes through the capacitor 53 to the base of the transistor T6 and is applied through the capacitor 54 to the base of the transistor Tin. (When switch S is closed the pacemaker works in a continuous manner and no pulses extend to the bases of the transistors T6 and TlO. In a similar way, the transistors T3 and T4 prevent the presence of a 60 Hz noise the application of pulses to the bases of the transistors T6 and TlO, so that the pacemaker in which can work continuously.)

Capacitor 57 normally charges from batteries 1-5 through potentiometers 35, 37 and resistors 61 and 6 3 on. When the voltage across the capacitor is sufficient to activate transistors T7 and T8, conduct these transistors and a strong current flows through them, increasing the potential in parallel the resistor 63. At this point, the transistor T9 is activated and the capacitor 6 5 discharges through the Transistor, the electrodes and the heart tissue while stimulating the heart chambers. After the transistor T9 is switched off the capacitor 65 charges up again in preparation for generating a further stimulation pulse. The setting of the potentiometer 35 determines the magnitude of the charging current for the capacitor 57. This, on the other hand, determines the ventricular pause interval. Whenever the voltage across capacitor 57 is high enough to activate transistors T7 and T8, the capacitor discharges through them so that another clock cycle can begin. The duration of the discharge is determined by adjusting the potentiometer 37. Since a strong current flows through the resistor 63 flows whenever the transistors T7 and T8 conduct is

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as obviously., ie '' -. .- ■: - i7 iie width de ν; Her? /:: ■ ~ "·. ~:. ·:. ■ ·

"ienn before the '.es Her · ./'".: -:.:> :. taner ventricle 3-part. Was it / -? gate? 6 and the Xcndes? · = ■ .-:: r. In such a Γ "ί_. - ,. ■.; ·. Pulse generated ,, the ar · ..; ---- ε- ■ -.-.> .: the voltage parallel ■ ν d -; - reaches level would have, Vr.:. ^ ';: .. stimulate a ventricle.: ■; -_:.: - r

if the Heart Kat ^ '^ ier ^au.f:':: -: = .: ;..

further spontaneous' · εΓ "- :::" "· .ΐτ

The circuit ^c - '; r -: = · -;' r --- ^ v in a similar manner a? -, r- ^ kc potentiometer 6 2., ~ Ϊ:: ;; r is applied, "as .. hard = - -11 · ges or 7eststeil- '- ::;:.! - ;; pulses causes -this:; ^3M.j: a ·.

saror 58 voilständi-j. :::::: .-. :; e-

c. the charge in parallel - '■. ':' ⁿ \ ~: \ activating the "rar--: - :. ·; :: ^; if an impulse occurs ~ aral-.e.: ■ ·. ': troden E" and E4 r ^; ; r -.-, r ^ «: -.: Potentiometers ^ 5 '-s ^c t · .ρ' -, τ. "ν ·: .-:

Tl2 turned una he '- "end · Fs is only the r * c ~ = t: TIO which the ^ ntla ^^ - ^first!".:; e 'switch the transistor. Γ .:; new VA clock interval

^only: änn ε-r. densator 53 himself ^ unHch = den and the '"T ans ι st

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a spontaneous ventricular beat is detected or an atrial pacing pulse is generated, it follows that only one atrial stimulation pulse following each ventricular beat can be generated.

By means of the cardiac pacemaker according to FIG. 1, it is possible to adjust the AV delay without changing the cardiac pacemaker rate to change. If the setting of the potentiometer increases, e.g. the VA interval increases (and the AV delay is thus reduced), but this has no effect on the ventricular pulse generator circuit and thus remains the pacemaker rate the same. However, it is not possible to change the pacemaker rate without changing the AV delay to change. If the setting of the potentiometer 35 is increased, and e.g. no adjustment to the If the potentiometer 62 is adjusted, the result is that the W interval increases, while the VA interval increases remains the same. This, on the other hand, leads to an increase in the AV delay along with a decrease in the Pacemaker rate.

With the pacemaker according to FIG. 2, it is possible to change the pacemaker rate without affecting the AV delay. The potentiometer 35 according to FIG. 1 is replaced by a stationary resistor 35b and a potentiometer 35a. The potentiometer 62 according to FIG. 1 is replaced by two potentiometers 62a and 62b connected in series. The dashed line 35a-62a represents a single shaft which couples the potentiometers 35a and 62a to one another in synchronism. The settings of these two potentiometers are changed in the same way when the pacemaker rate adjusting shaft is rotated. In further respects the pacemaker of FIG. 2 operates in the same way as that of FIG. 1.

It can be seen that changing the setting of potentiometer 62b changes the VA interval (and hence the AV delay) without affecting the pacing rate is influenced in some way. This is because the potentiometer 62b only charges the capacitor

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58 in the auricular impulse <roi? '· - ^? - ir. -f ix. b ' ~. ίΓ-ies hits. also for " the pacemaker rorrir Fi α. I / u, in which a change in the * Finst-r-lb.:n~ ? .ec Focft ^v : cioneters 62 changes the AV delay , ~ h] v- -: ^T i ~ Hers ε "r-rltt ~ .3cher- frequency to influence. how further cber. In contrast to the steps α:, | -; ': r according to FIG. 1, however, the pacemaker gene-.G Fi:. 2 a change in the pacemaker frequency, - without 'λ :; any * .- :, 'he change in AV delay causes --- iri, "-'enn the ^r ve" le 35a - 62a is rotated, so as to cause an increase in the impedance of the potentiometer 35a (and thus also the setting of the potentiometer 62ai, d ^{^;} TIG ö <r ?. condenser 5 "long to get to the Aktivierungsoegel eggs transistors T7 and T8 charge.

This leads to an increase ir ce ~ ^{T: r} v 'interval, De, however, the impedance of the potentiometer.' · C2a is also reduced , the condensate needs 58 longer to reach the activation level of the transistrcer. T II and T 1? i ~ Following its initial ^c > · t Ιάΐΐϊηα by ^ r. Charge transistor TlO. If both RC-Laä ^ J-.reiee linear and: the potentiometers 35a and 62a are identical, b: their every increase or decrease in de; T ^ "'- Inr.c.rvall to an identical increase or decrease ir. de.T. 7? -, - interval, Since the AV delay is equal to the difference between these two intervals , the result is, - 3aC the AV delay is not influenced by the change in the step frequency .

The resistor 35b in the Her ^ Kammerifnoulsgebtr is provided to ensure a minimum V \ * - interval and this regardless of how low 'the setting of the potentiometer 35a is. A similar stationary resistor can be seen in series with the potentiometers 6 2a and 62b if this is appropriate. Similarly T- ⁷ else it is possible another potentiometer Ir series with the potentiometer 35a vorzuseher, obvohl a 'noassung on

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di “Setting this potentiometer would necessarily ^{affect the 7} W delay along with the pacing rate. Fs is the synchronization of at least one potentiometer in the ventricular pulse generator circuit with at least one potentiometer in the atrial pulse generator circuit, which allows the pacemaker rate to be changed without influencing the AV delay.

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Claims (1)

Claims (ij / atrial and ventricular pacemaker characterized by a ventricular pulse generator circuit for generating a ventricular stimulation pulse for transmission to a patient's heart following the Sequence of a ventricular pause cycle interval, first potentiometer for changing this cardiac pause cycle interval, Arrangements for detecting a spontaneous heart beat of the heart of a patient, or the generation of a ventricular stimulation imtmlses for the purpose of synchronizing the Cardiac chamber imnuIsor with the heartbeat of a patient, Timer arrangements responsive to the operation of the detection arrangements for measuring an atrial pause clock interval, second potentiometer for setting the width of the atrial pause clock interval, arrangements based on the Address the expiration of the atrial pause clock interval to generate an atrial stimulation pulse that is sent to the heart of the Patient is dispensed and instructions to control the automatic adjustment of the second potentiometer when the first potentiometer is adjusted. 2. Atrial and ventricular pacemaker according to claim 1, characterized in that the Control assemblies include a shaft that is synchronously coupled to the first and second potentiometers. 3. Atrial and ventricular pacemaker according to claim 2, characterized in that the Ventricular noise cycle interval has a linear function represents the setting of the first potentiometer and the width of the atrial pause clock interval is a linear function represents the setting of the second potentiometer, and the control arrangement acts in such a way that a constant Difference between the ventricular pause clock interval and the atrial pause clock interval is maintained. - 13 - 309843/0405 23H315 4. Atrial and ventricular pacemaker according to claim 3, characterized in that a third potentiometer for setting the width of the atrial pause clock interval are provided regardless of the width of the cardiac cannon pause cycle interval. 5. Atrial and ventricular pacemaker according to Ansoruch 1, characterized in that the ventricular pause clock interval is a linear puncture of the Adjusting the first potentiometer and the width of the atrial pause clock interval is a linear function represents the setting of the second potentiometer, and the control arrangement acts in such a way that a constant Difference between the ventricular pause cycle interval and the atrial pause cycle intervalI is maintained. 6. Atrial and ventricular pacemaker according to claim 5, characterized in that third Potentiometer for setting the width of the pre-hopping cycle interval regardless of the width of the ventricular pause cycle interval are provided. 7. Atrial and ventricular pacemaker according to Ansoruch 1, characterized in that a third potentiometer for setting the width of the atrial pause clock interval are provided regardless of the width of the ventricular pause clock interval. B. Atrial and ventricular pacemaker, characterized in that ventricular pulse generator for Generating ventricular stimulation pulses for transmission to the patient's heart, first potentiometer for Changing the frequency with which the ventricular stimulation pulses are generated, arrangements for synchronizing the Ventricular pulse generator with the heartbeat effect of a patient's heart, timer arrangements for synchronous operation with the patient's heartbeat to measure an atrial pulse interval, second potentiometer for setting - 14 - 309843/0405 23U315 the width of the atrial pulse interval, arrangements, which respond to the expiration of the atrial pause clock interval for generating an atrial stimulation pulse and Arrangements for controlling the automatic adjustment of the second potentiometer when the first potentiometer is adjusted are provided. 9. Atrial and ventricular pacemaker according to claim B, characterized in that the Frequency at which the ventricular pacing pulses are generated, a linear function of the timing of the first Potentiometer and the width of the atrial pause clock interval is a linear function of the setting of the represents a second potentiometer and a control arrangement, the time interval between the generation of an atrial stimulation pulse and generating the next ventricular pacing pulse regardless of the setting of the first arrangements keeps constant. 10. Atrial and ventricular pacemaker according to claim 9, characterized in that third Potentiometer for changing the width of the atrial pause clock interval provided independently of the control arrangement are. 11. Atrial and ventricular pacemaker according to claim 8, characterized in that third Potentiometer for changing the width of the atrial pulse interval are provided regardless of the control arrangement. 12. Atrial and ventricular pacemaker, characterized in that the ventricular pulse generator for Generating ventricular stimulation pulses for transmission to a patient's heart, first potentiometer for changing the frequency with which the ventricular stimulation pulses are generated, arrangements for synchronizing the ventricular pulse generator with the heartbeat of the pa- - 15 - 309843/0405 23U315 tients, timer arrangements for synchronous operation with ' the heartbeat of a patient for measuring an atrial pause clock interval, second potentiometer for setting the width of the atrial pause clock interval, arrangements that relate to the expiration of the atrial pause clock interval for generating an atrial pacing pulse for transmission to a patient's heart, responsive and control arrangements the automatic setting of the width of the atrial pause clock interval when the first potentiometer is set and the rate at which the ventricular pacing pulses are changed are generated. 13. Atrial and ventricular pacemaker according to claim 12, characterized in that the The frequency at which the ventricular pacing pulses are generated, a linear function of the setting of the represents the first potentiometer and the width of the atrial pause clock interval represents a linear function of the adjustment of the second potentiometer, as well as the control arrangement the time interval between the generation of one atrial pacing pulse and the generation of the next Cardiac stimulation pulse regardless of the setting the first potentiometer keeps constant. 14. Atrial and ventricular pacemaker according to claim 13, characterized in that third Potentiometer for changing the width of the atrial pause clock interval provided independently of the control arrangement are. 15. Atrial and ventricular pacemaker according to Ansnruch 12, characterized in that third Potentiometer for changing the width of the atrial pause clock interval provided independently of the control arrangement are. 309843/0405