Abstract:
A programmer for cardiac implantable medical devices, including an accelerated test mode of the operating parameters. The programmer includes a user interface ( 10 ) that is used to define the tests to be performed on the implant and display the results thereof. These tests includes: ventricular and atrial sensing sensitivity, ventricular and atrial lead impedance, and ventricular and atrial capture threshold. Each test step involves (i) a predetermined setting of the operating mode, pacing rate and atrio-ventricular delay of the implantable device, (ii) collection of the operating data of the implantable device according said predetermined settings, and (iii) processing and display of thus collected data. There further exists one test step of time compression along which at least some of the ventricular and atrial tests for a same parameter are executed simultaneously during a common step, preferably the tests of sensing sensitivity and lead impedance. The user interface allows for a preliminary selection of the tests to be performed, and the programmer is operated to execute these tests, linked in sequence, without any intervention by the user.

Description:
FIELD OF THE INVENTION 
     The present invention is related to external programmers intended to be used with “active implantable medical devices”, as such devices are defined by the Jun. 20, 1990 directive 90/385/CEE of the Council of the European Communities, and more particularly to those external programmers for use with implantable cardiac pacing, resynchronization, cardioversion and/or defibrillation devices. 
     BACKGROUND OF THE INVENTION 
     The programmer allows a practitioner to interrogate the implantable device and read the contents of its memories, and to program the implantable device so as to modify its settings or drive the execution of various algorithms, to provide software updates, to operate tests, etc. 
     Once the implantable device is positioned in a patient, and its leads connected, it is necessary to verify that a plurality of parameters are properly set at the moment of the implantation procedure, and thereafter on a regular basis or from time to time during follow-up visits. 
     The main parameters to be tested are: sensing sensitivity, lead impedance and capture threshold. These tests are typically performed for both the atrium and ventricle. In the case of a defibrillator, the test also covers the continuity of the shock coil or electrode, and the charging time for the shock capacitor to reach its nominal energy value. Finally, for multi-site devices, notably the implantable devices for cardiac resynchronization therapy (“CRT”), it is also necessary to test the parameters relating to the left ventricle (impedance of the coronary lead for left ventricular pacing, and capture threshold of left ventricular electrode). Performance of these tests is typically controlled by the practitioner, through the programmer. 
     U.S. Pat. Nos. 7,003,349, 6,618,622 and 5,833,623 describe some devices adapted to the execution of such tests. The practitioner can notably use and create “scripts” that define a sequence of operations through which the different requested tests are automatically linked to perform in sequence, one after the other. 
     When the practitioner schedules performance of one test, it results in putting the implanted device in a particular operating mode (DDI, DOO, etc.), with a particular pacing rate (the value being either chosen by the practitioner or set by the programmer to a default value) and a particular AV delay. The programmer then collects the operating data of the implanted device with such predetermined settings, and displays on a screen the result of the test thus performed. These tests can be practically launched by pressing a button available to the practitioner (e.g., an actual physical button, or a clickable zone on the screen), with each pressing of the button triggering the corresponding test. 
     The time required for executing the various tests is a major issue. In the first place, it is highly desirable to shorten the testing phase, for it constitutes a preliminary step to any interpretation or diagnosis, and therefore a dead time throughout the duration of the visit to the practitioner. Furthermore, from the patient&#39;s viewpoint, during the tests the implanted device is adjusted with test-specific predetermined settings, and its operation is not that for which it is normally parameterized. The implanted device is therefore not adapted to the patient&#39;s physiology throughout the duration required for these tests to be performed. It is therefore highly desirable, for a safety purpose, to abbreviate as much as possible this phase of tests. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     It is, therefore, an object of the present invention to reduce the duration required for executing the various tests of the implanted device operation. 
     Advantageously, one skilled in the art will observe that, in accordance with the present invention, the total duration of the implanted device tests can be reduced to less than one minute, whereas in the known practice, this duration is never shorter than 2 min 15 sec or 2 min 30 sec. This reduction in time is significant. 
     It is yet another object of the present invention to propose to the practitioner the execution of specific actions that are automatically linked to perform in sequence, one after the other, the execution of the test steps, without any need for the operator&#39;s intervention, including, but not limited to: memorization (saving to memory) of results, print-out of a report, activation of a diagnosis-aid module, etc. 
     Broadly, the present invention is directed to operating a temporal compression of the test sequence by automatic performance of the different tests, with overlap (simultaneous execution) of some of them. 
     One aspect of the invention is directed to a programmer that, in a manner that is already known per se in the prior art (see, for example, U.S. Pat. No. 7,003,349), comprises a telemetry system for a bidirectional coupling with the implant, and a user interface, for defining the tests to be performed on the implant and displaying the results of these tests. These tests comprise at least part of the tests selected from among the following group: ventricular sensing sensitivity, atrial sensing sensitivity, ventricular lead impedance, atrial lead impedance, ventricular capture threshold, atrial capture threshold. The programmer also comprises command means for executing a plurality of test steps, each step comprising (i) a predetermined setting of the operation mode, pacing rate and atrio-ventricular delay of the implanted device, (ii) collecting the implanted device operating data as a function of said predetermined settings, and (iii) processing and display of the data thus collected. 
     In a manner characteristic of the present invention, the plurality of test steps comprises at least one step of time compression, along which at least some of the ventricular and atrial tests of a same parameter are executed simultaneously during a common step. The term “simultaneously” as used herein means that the concerned tests are concomitant, and they are: executed in parallel over a same time interval, in contrast to an execution that would be performed “successively” or “alternately” or “sequentially”. 
     According to another characteristic of this invention, the user interface comprises means for preliminary selection by the user of the tests to be performed, and the command means is able to link in a sequence, without any intervention by the user, the execution of the corresponding selected test steps. 
     According to various particular embodiments of this invention, the command means is preferably able to execute at least one step of adjustment, interpositioned between two test steps implying a change of the pacing mode and/or rate of the implanted device, and/or a step of adjustment of the pacing mode and/or rate and/or atrioventricular delay of the implanted device, after execution of the last test step. 
     The command means is preferably able to command the execution of at least the following: one simultaneous test of atrial and ventricular sensing sensitivity, over N 1  cycles, preferably N 1 =5 cycles; one simultaneous atrial and ventricular lead impedance test, over N 2  cycles, preferably N 2 =1 cycle; one step of ventricular capture threshold, over N 3  cycles, preferably N 3 ≦18 cycles; one step of atrial capture threshold, over N 4  cycles. Further, in a preferred embodiment, the step of the ventricular capture threshold test is executed over N 3 =N 3 ′+N 3 ″ cycles, N 3 ′ being a fixed number of calibration cycles, and N 3 ″ a variable number of cycles of capture test with successive decreasing pulse amplitudes, the command means being able to terminate the ventricular capture threshold test as soon as a loss of capture is detected. 
     In yet another embodiment, the command means is also able to command the execution of at least the following: one step of continuity of the shock coil or shock electrode; a step of test of the charging time of the shock capacitor; and distinct steps of left and right ventricular capture threshold tests; 
     The user interface preferably comprises means for preliminary selection by the user of at least one specific action to be linked to perform in sequence, without any intervention by the user, after execution of the test steps. Notably, the actions are taken from among the group comprising: memorization of the test results in the implanted device memory, memorization of the test results in the programmer, print-out of the test results and activation of a diagnosis-aid module following the tests. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features, advantages and characteristics of the present invention will become apparent to a person of ordinary skill in the art in view of the following detailed description of preferred embodiments of the invention, made with reference to the drawings annexed in which like reference characters refer to like elements, and in which: 
         FIG. 1  illustrates a first example of a display screen constituting the user interface of the programmer of this invention, for executing the tests of operation of a cardiac pacemaker; 
         FIG. 2  is a flowchart showing the linking of the different test steps likely to be scheduled by the practitioner by means of the user interface of  FIG. 1 ; 
         FIG. 3  illustrates a second example of a display screen constituting the user interface of the programmer of this invention, for executing the tests of operation of a multisite device including features of resynchronization and/or defibrillation; and 
         FIG. 4  is a flowchart showing the linking of the different test steps likely to be scheduled by the practitioner by means of the user interface of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     One will now describe exemplary embodiments of a device according to the present invention. 
     Regarding the software aspects thereof, this invention can be implemented through an appropriate programming of the operating software of a known programmer. This invention can notably be applied to retrofit the REPLY and PARADYM brand programmers commercialized by ELA Medical, Montrouge, France, intended to program implantable devices such as SYNERGY and SYNDELI brand devices also commercialized by ELA Medical. These programmers are microcomputers specifically configured so as to implement the programming features, in conjunction with a telemetry head connected to the computer and coupled to the implantable device through inductive or radiofrequency (RF) communications protocols in a known manner. 
     Adapting these devices for implementing the features of this invention by software programs of the functions described herein is believed to be easily within the abilities of a person of ordinary skill in the art, and will therefore not be described in detail in this document. On  FIG. 1 , reference  10  illustrates the graphic user interface to be displayed to the practitioner on a programmer display screen. In a manner already known per se, this interface comprises an “interrogate” button  12  for commanding the interrogation of the memories and registries of the implanted device, and a program (“prog.”) button  14  for programming the operating parameters thereof. The screen  10  further comprises a certain number of buttons  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28  allowing to select respective functions including: viewing the implanted device status (“overview”  16 ), triggering of tests (“Smartcheck”  18 ), activation of a diagnosis-aid module (“Diag.”  20 ), parameterization (“Param.”  22 ), verification (“Tests”  24 ), report (“Report”  26 ), patient identification (Patient  28 ). 
     The button  18  for triggering the tests is associated with a “start” or “play” button  30 , intended to execute, following the manner that is specific to this invention, the different tests of operation of the implanted device. An “end” button  32  allows to terminate the follow-up session. 
     The display screen comprises a certain number of checkboxes  34 , allowing the practitioner to select the tests he/she wishes, or not, to execute: ventricular sensing sensitivity (V sensing), atrial sensing sensitivity (A Sensing), ventricular lead impedance (Impedance V), atrial lead impedance (Impedance A), ventricular capture threshold (V Autothreshold), which can be automatically determined by the implanted device, atrial capture threshold (A threshold), which is usually determined manually or “by hand”, for it requires an interpretation of the data by the practitioner. 
     Regarding the sensing sensitivity tests and capture threshold tests, a field  36  shows the rate to which the pulse generator will be adjusted, the default value being possibly modifiable by the practitioner. The “current” fields  38  allow to display the respective test results after execution of these tests, and fields  40  show the results of the test previously performed by the implant, e.g., at the start of the session, for this same parameter, with the corresponding date. Indeed, the values of certain parameters, notably the impedance and the capture threshold, are automatically measured by the implant in an autonomous manner, and at regular intervals (for example, every 5 hours). These are the values that are displayed in the fields  40 . 
     A button  42  allows to review a posteriori the electrocardiogram (ECG) and electrogram (EGM) associated to the execution of these tests, and a “Save Config.” button  44  allows to store in a memory of the programmer, the results of these tests (the memorization of test results in the implant being subjected to another command). 
     The interface  10  also comprises a certain number of checkboxes  46  allowing the practitioner to command the execution of specific actions by the programmer, immediately after the achievement of the test sequence: activation of a diagnosis-aid module, saving the test results in the implant memory, reset of this memory, print-out of a report. 
     The sequence of the different tests is represented in the flow-chart of  FIG. 2 . The illustrated sequence corresponds to the execution of the totality of the tests that are possibly selectable through checkboxes  34 , but should some of these boxes be not checked, the corresponding steps would of course be omitted or skipped during the running of the whole sequence. 
     The first step S 1  consists of evaluating the atrial and ventricular sensing sensitivities. These two measurements are performed simultaneously along this single step S 1 . Typically, the settings of the implanted device are: DDI mode, AV delay of 250 ms, default pacing rate of 30 bpm (or any other value programmed by the practitioner). This step can be performed in only 5 cycles, corresponding to a duration of 10 seconds at a pacing rate of 30 bpm. 
     The following step S 2  is a step of adjustment allowing to compensate the modifications of the operating mode, AV delay and pacing rate between the step S 1  and following step S 3 . In this step of adjustment S 2 , the settings of the implant become: DOO mode, programmed AV delay, pacing rate of 100 bpm. The typical duration is 2 cycles. 
     The following step S 3  is a step of measurement of the ventricular and atrial lead impedances. With the settings of the previous step S 2  (DOO mode, programmed AV delay, 100-bpm pacing rate), this test can be performed in only one cycle, simultaneously for ventricular and atrial electrodes. It is notably possible to implement a technique for lead impedance measurement that is described in U.S. Pat. No. 6,907,290 (commonly assigned herewith to ELA Medical). 
     The following step S 4  is a step of determination of the ventricular capture threshold. The settings of the implanted device are: DOO mode, AV delay of 94 ms, default pacing rate of 100 bpm (or any other value programmed by the practitioner). This step S 4  is composed of a first phase of calibration, typically over 7 cycles, followed by a step of capture threshold test with decreasing pulse amplitudes. In a preferred embodiment, the test is considered completed when a loss of capture is detected, that allows to shorten the duration of this step. The maximum duration of this step S 4  is preferably 18 cycles (with the least favorable assumption when the loss of capture is not detected, or only detected in the last cycle). It is notably possible to implement a technique of adjustment of the pacing pulse amplitude that is described in U.S. Pat. No. 6,487,451 (commonly assigned herewith to ELA Medical), with a phase of calibration followed by a phase of search for a loss of capture. 
     The following step S 5  is a step of measurement of atrial capture threshold. Though there are existing techniques for automatic measurement of this threshold, such as that described in US published patent application US 2007/0,156,188 (commonly assigned herewith to ELA Medical), it may be preferable, for safety reasons, to rely upon an actual interpretation performed manually by the practitioner. 
     To that end, the pulse generator is driven over 10 cycles with the following settings: DAO mode, AV delay of 250 ms, default 100-bpm pacing rate (or any other value programmed by the practitioner). At the end of these tests, the practitioner indicates (step S 6 ) the value of the atrial capture threshold based upon his/her interpretation of the cardiac signals that have been displayed on an intermediate screen. 
     When these different tests have been completed, the sequence ends with two cycles of adjustment, as shown in step S 7 , so as to put the pulse generator back in its original configuration, as it was prior to the tests. 
     One will observe that the steps of adjustment S 2  and S 7  are required so as to allow an automatic linking of all the successive steps, which differs from prior known configurations in which the tests were commanded one after the other by the practitioner, for example, through successive clicks on a button. Such tests were executed individually, interpreted visually, and the settings determined for each of the tests, every time, without any consideration for the settings of the previous test. On the contrary, in accordance with the present invention, the settings for a given test are dependent upon those used for the previous test, and for this reason, for example, in order to link the tests S 1  of sensing sensitivity and S 3  of impedance, it is necessary to have an intermediate step of compensation S 2  in order to realize the change of operating mode (from DDI to DOO in this example) and pacing rate (from 30 bpm to 100 bpm in this example) in a totally automatic manner. 
     With the numbers of cycles and pacing rates described above, one can reach an overall duration of approximately 45 seconds at the most for steps S 1 -S 5  and S 7  (the duration of the ventricular capture threshold test can usually be reduced, as explained above). If it is assumed that the average duration for step S 6  of interpretation of the atrial capture threshold test and selection of the threshold value by the practitioner is about 10 seconds, one gets an overall duration for steps S 1 -S 7 , of 55 seconds at the most—to be compared to usual durations of 2 min 15 sec to 2 min 30 sec with a manual test sequence. 
       FIG. 3  illustrates the interface that is displayed to the practitioner for the test of a multisite device including features of resynchronization and/or defibrillation/cardioversion, in accordance with an alternate embodiment of the present inventions. 
     This interface similarly comprises the checkboxes  34 ′ present in the interface of  FIG. 1 , as well as additional parameters to be tested, notably including (as a function of the type of implanted device): left ventricular lead impedance (“LV impedence”), continuity of shock coil (so-called “supraventricular” electrode and/or distal ventricular electrode) (“SV continuity”), charging time of the shock capacitor to its nominal energy (“charging time  34 J”), left ventricular capture threshold (“LV threshold”), eventually right ventricular capture threshold in manual mode (“RV threshold”) (to test manually, by comparing them, the capture thresholds for the two ventricular cavities), and test of optimization of a resynchronization therapy (“CRT optimization”). 
     The remaining information presented on the screen are the same as those referred to in  FIG. 1 . 
       FIG. 4  is a flowchart that illustrates the linking of the different selected test steps. In additional to the steps S 1  to S 7  as described above with respect to  FIG. 2  (step S 6  is not shown in  FIG. 4 ), the sequence comprises the following additional steps:
         step S 11  for the test of continuity of the defibrillation coil(s),   step S 12  for the charging time test,   step S 13  for adjustment (two cycles) to restore the pulse generator to its programmed values for operating mode, AV delay, pacing rate and amplitude,   step S 14  for left ventricular capture threshold (LV threshold), with following parameters: DAO mode, AV delay of 94 ms, default 100-bpm pacing rate (or any other value programmed by the practitioner). The total duration of this step S 14  is of 10 cycles.       

     Here again, the automatic linking of the different steps, and the temporal overlap of the atrial and ventricular tests, allow a significant gain in reducing the test duration in accordance with the present invention as compared to the usual sequence of the known prior art. 
     One skilled in the art will appreciate that the present invention can be practiced by other than the described embodiments and particular values referenced for the various operating and programmable parameters, which are presented for purposes of illustration and not of limitation.