Patent Publication Number: US-8977359-B2

Title: System for setting programmable parameters for an implantable hypertension treatment device

Description:
RELATED APPLICATION 
     This application is a continuation of U.S. application Ser. No. 11/254,042 filed Oct. 18, 2005, now issued as U.S. Pat. No. 8,712,522, the disclosure of which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates generally to electrical therapeutic systems for hypertension treatment. More particularly, the present invention relates to methods and apparatus for setting programmable parameters for an implantable hypertension treatment device. 
     Implantable devices for treating high blood pressure or hypertension by stimulating various nerves and tissue in the body are known and described, for example, in U.S. Pat. No. 3,650,277 (stimulation of carotid sinus nerve), U.S. Pat. No. 5,707,400 (stimulation of vagal nerve), and U.S. Pat. No. 6,522,926 (stimulation of baroreceptors). While many aspects of these implantable devices are similar to implantable devices used to treat cardiac arrhythmias, such as pacemakers and implantable defibrillators, there are significant differences in the application and operation of implantable hypertension devices due to the fact that the slower responding baroreflex system is being stimulated, instead of the rapid response of cardiac stimulation used for pacemakers. 
     Implantable electronic medical devices typically require post-implantation programming of certain parameter values in order to establish proper patient-specific performance. For example, implantable cardiac stimulation devices, such as pacemakers and implantable cardiac defibrillators (ICDs) utilize a threshold margin testing procedure in which the level of electrotherapy pulses is established for the specific patient. Each patient will have a unique tissue impedance and susceptibility to the electrotherapy signaling, and the configuration of electrodes can produce different results for the same stimulation pulse. As a result, it is necessary to program certain parameter values in the pacemaker or ICD to establish optimum therapy for that patient for a particular implantable device and electrode configuration. 
     In the case of a conventional pacemaker, the object of such parameter programming is to establish the voltage level of the pacing pulses such that the pulses are of a sufficiently high amplitude to achieve reliable capture of the patient&#39;s heart while being of a minimal amplitude to achieve the desired therapy to provide the longest possible battery life for the device. Similarly, in the case of implantable defibrillators, the defibrillation pulse amplitude is set to the minimal level to achieve reliable electrotherapy with minimal tissue damage and maximum battery life. In each case, the programmable parameters are typically set at some safety threshold margin above the measured pacing capture or defibrillation threshold values. 
     Automatic systems for testing and configuring the threshold parameters of implantable cardiac stimulation devices are described, for example, in U.S. Pat. Nos. 5,320,643, 5,487,752 and 6,311,089. Examples of implantable cardiac stimulation devices that automatically self-configure the operating parameters for the device using built-in measurement/circuitry and sensors and some type of configuration algorithm are described in U.S. Pat. Nos. 6,463,325 and 6,587,723. U.S. Pat. No. 6,371,922 describes optimizing cardiac stimulation pulses delivered by a pacemaker based on measuring Baroreflex sensitivity. 
     A common aspect to these conventional automatic device configuring systems for implantable cardiac stimulation devices is that the physiological response of the patient is generally readily observable a short time (on the order of seconds) following an administration of electrotherapy by the implantable device. Another common aspect is that the physiological response of cardiac stimulation is generally binary in nature. Stated another way, the desired physiological response is either present or absent. In the case of a pacemaker, the pacing pulse for the heart is either captured or not captured; in the case of a defibrillator, the cardiac rhythm is either restored, or not restored. Detecting the presence or absence of these fast and easily discernable physiological responses to the electrotherapy signals applied to the autonomic nervous system is therefore a relatively straight-forward endeavor. Furthermore adjustment of the electrotherapy signaling to optimize device performance in response to the physiological responses (or lack thereof) can be done incrementally in a relatively short period of time. 
     By contrast, implantable devices for treating hypertension by regulating blood pressure in a patient may induce a physiological effect in the sympathetic nervous system that is not binary in nature and that tends to be protracted or sustained. For example, baroreceptor stimulation effects an incremental, or gradual, change in blood pressure that is observable only after a relatively longer period of time (on the order of minutes). Therefore, conventional automatic device configuration systems and methods developed for implantable cardiac stimulation devices are not directly applicable for configuring hypertension treatment devices. 
     Presently, hypertension treatment devices are configured based on monitoring performed manually by clinical personnel. This process of dose-response testing for a hypertension treatment devices requires the clinical personnel to have an instrument for taking blood pressure measurement of the patient, such as an automated blood pressure measurement system like the Dynamap® blood pressure system. In addition, the patient&#39;s heart rate must be monitored to insure that the heart rate does not drop to a lower than desired value. Therefore, the patient is also connected to a real time, or continuous, heart rate monitor, such as a surface ECG or SP0 2  measurement device. Finally, the clinical personnel must manually operate the programmer for the implantable hypertension treatment device to repeatedly perform the testing routine that typically includes: (a) programming the implantable hypertension treatment device, (b) monitoring the heart rate while waiting a prescribed number of minutes to take initiate measurement of the hemodynamic parameters of the patient, (c) manually starting the measurement of the hemodynamic parameters of the patient, (d) manually recording the results of the hemodynamic parameters of the patient and correlating those results to the programmed settings, (e) determining if the recorded results indicate whether the dose-response has stabilized, and (f) if not, continue repeating the test process at the next higher dose response level. Presently, all of these instruments are separate from the programmer and require separate monitoring and operation from the programmer device. 
     When configuring an implanted hypertension treatment device by this kind of dose-response test process, the clinical personnel must keep track of issues such as the time until a physiological response to a change in electrotherapy administration, operation of the device programmer, operation of the blood pressure measuring apparatus, recording measurements, and correlating measurements with the most recent electrotherapy set point, all while continuously monitoring the safety of the patient during the procedure by keeping track of the patient&#39;s heart rate. Because such procedures are operator intensive, subject to measurement variability, and time-consuming, there are significant drawbacks to the current methods for configuring implanted blood pressure regulating devices. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is a system for automating the setting of programmable parameters for an implantable hypertension treatment device. One aspect of the present invention integrates a real time heart rate monitor and a hemodynamic monitoring system with the programmer system for an implantable hypertension treatment device. A series of tests are automatically performed to set programmable parameters for the implantable hypertension treatment device under program control that permits automatic operation without clinician intervention. In one embodiment, a predetermined level of a dose-response evaluation is initiated for each test in the series. Preferably, the programmer system monitors the heart rate to determine whether a hemodynamic measurement should be initiated at all for a given test, as well as whether the hemodynamic measurement should be initiated earlier or later than a predetermined settling period for assessing the sympathetic nervous response to the test dose. In one embodiment, this determination is based on heart rate stability/instability. Alternatively, other indicators of sympathetic/parasympathetic tone, such as heart rate variability, may be used to trigger/delay the timing of the hemodynamic measurement. 
     In one embodiment, the heart rate monitor and hemodynamic measurement system are separate devices in communication with the programmer system. In another embodiment, the heart rate monitor and hemodynamic measurement system are incorporated into the programmer system. In another embodiment, the hemodynamic measurement system and/or the heart rate monitor system may be integrated with the implantable hypertension treatment device that is in communication with the programmer. In a further embodiment, the hemodynamic measurement system and/or the heart rate monitor system may be implanted separately from the implantable hypertension device and could be in communication with the programmer, either directly or via the implantable hypertension device. 
     The present invention avoids errors that can be associated with the existing manual testing procedures for setting programmable parameters for implantable hypertension treatment devices. The present invention also permits the testing to be performed more rapidly and with minimal clinician intervention during the procedure. The integration of the programmer system in accordance with the present invention improves the overall safety of the test procedure as the system can more rapidly detect and respond to a low heart rate condition than manual monitoring and intervention. 
     Unlike the prior art testing techniques for setting programmable parameters for implantable cardiac stimulation devices, the dose-response characteristics associated with an implantable hypertension treatment device are much more linear in that the hemodynamic response of various programmed conditions needs to be measured in order to determine an algorithm or model of the response. The clinician may use the output of this model to guide the clinician in programming the parameters of the implantable hypertension treatment device so that the desired hemodynamic response is achieved. The dose response procedure of the present invention also takes significantly more time than, for example, the pacemaker threshold margin test, because the hemodynamic response to certain programmed conditions may initiate a response nearly immediately after programming, or it may take several minutes for the patient to achieve a stabilized response. 
     Preferably, the clinician monitors the test procedure from a remote viewing/monitoring location. In one embodiment, the programming system includes a remote control to facilitate the remote monitoring of the test procedure. Preferably, the remote control would be connected with the programming system by a wireless connection, such as RF, infrared or optical, although it will be recognized that the remote control could also be provided with a wired connection. The present invention recognizes that even modest amounts of interaction or talking with a clinician can cause a change in the blood pressure of the patient, thereby affecting the results of the test procedure. The automated nature and integration of the present invention permits the clinician to avoid interaction with the patient during the test procedure so as to minimize the chances of inadvertently affecting the results of the test procedure. 
     In one embodiment, the hemodynamic measurement system may be a discontinuous or non-real time measurement system, such as an inflated/deflated cuff where measurements are taken periodically rather than continuously. Alternatively, a real-time waveform measurement system, such as a Finometer™ blood pressure instrument manufactured by Finapres® or continuous pressure monitor, may be utilized. In the embodiment in which a real-time waveform measurement system is used, the hemodynamic measurement system may be used in place of the heart rate monitor, or to augment the heart rate monitor, in terms of the assessment of whether a stable response has been achieved for a given dose-response test. 
     The present invention enables automated and faster integration of data from the test results, and in one embodiment graphic display of the test results, to assist the clinician in determining the desired parameters for the implantable hypertension treatment device. In this embodiment, the programmer system and/or the implantable hypertension treatment device include data storage for storing dose response characteristics, preferably including historical dose response characteristics for the given patient. These dose response characteristics may be displayed to the clinician for diagnostic purposes, as well as for setting the programmable parameters for the implantable hypertension treatment device. In another embodiment, the historical data may also be used to shorten up the test period for the series of dose-response tests. For example, if past data has reasonably determined the response threshold and response slope, a new threshold and slope may be determined with few test conditions by, for example, using the previous threshold and response slope to interpolate among fewer dose response test points. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an overview block diagram illustrating a programming system in accordance with one aspect of the present invention interfaced with a patient and with a hypertension treatment device implanted in the patient. 
         FIG. 2  is a schematic diagram illustrating an exemplary arrangement of programming system components and their interface with one another and with an hypertension treatment device implanted in a patient. 
         FIGS. 3A-3D  are block diagrams illustrating various examples of arrangements between a programming system, patient monitors, and an implanted hypertension treatment device within the spirit of the invention. 
         FIG. 4  is a schematic diagram illustrating parts of a programmer according to one embodiment of the invention. 
         FIGS. 5A-5B  are flow diagrams illustrating various methods of configuring an implanted device via dose-response testing. 
         FIGS. 6A and 6B  are graphs showing the relationship between systolic blood pressure and heart rate as a function of pulse amplitude for a series of dose-response tests. 
         FIG. 7  is a flow chart of one method of quickly predicting effectiveness for each of a plurality of dose-response tests prior to making blood pressure measurements for a given dose-response test. 
         FIG. 8  is a is a diagram illustrating one method of skipping/terminating levels in a series of dose-response tests based on predictive/interpolative analysis of previous dose-response test. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a schematic diagram illustrating a programmer system  100  for a hypertension treatment device  102  implanted in patient  104 . Programmer system  100  is generally adapted to automatically conduct dose-response testing in the patient using the treatment device  102 , and to optionally determine a suitable operating point or calibration curve for the treatment device  102  based on the dose-response testing and program the implanted treatment device  102  accordingly. 
     Programmer system  100  includes a CPU  106  that is configured with machine-readable instructions to execute its operating functions. CPU  106  is communicatively coupled with a patient monitoring sub-system  108 , a device configurator sub-system  110 , and operator interface sub-system  112 . The communicative coupling can include any suitable arrangement for the exchange of data, control, and other such communication between the aforementioned sub-systems of programmer system  100 , including a data bus, serial communications, analog signaling, wireless communications, and the like, and combinations thereof. 
     In one type of embodiment, the CPU  106 , patient monitoring sub-system  108 , device configurator sub-system  110 , and operator interface  112  are closely integrated into a single device or system. In other types of embodiments, one or more of these sub-systems is implemented as a separate device that is operatively interfaced into the overall system, but not necessarily fully controlled by CPU  106 . In one such embodiment, for example, one or more sub-systems have their own CPU (not shown) configured to control only the associated sub-system, and only an exchange of data takes place between loosely-integrated sub-systems (i.e., no control or configuration information is exchanged). Persons skilled in the art will recognize that, for one or more of these sub-systems, any degree of integration into the greater system is within the spirit of the invention. 
     Patient monitoring subsystem  108  reads one or more sensors configured to observe the physiological condition of patient  104 . Preferably, patient monitoring sub-system  108  reads at least the patient&#39;s hemodynamic condition. Examples of sensors suitable for taking these measurements include electrocardiogram (EKG) sensors  114 , pulse oximetry sensor  116 , cuff-type blood pressure sensor  118 , and implanted blood pressure sensor  120 . Additionally, hemodynamic monitoring can include cardiovascular resistance information and sympathetic/parasympathetic tome information (not shown). Sensors can be discontinuous, or non-real-time, such as a cuff-type blood pressure measuring device. Sensors can also be of the continuous type, such as a Finometer™ blood pressure instrument manufactured by Finapres®. As illustrated, the implanted blood pressure sensor  120  can be a part of implanted treatment device  102 . Similarly, the implanted treatment device can include other hemodynamic sensors, such as a heartbeat sensor (not shown) or blood oxygenation sensor (not shown). Patient monitoring subsystem  108  is interfaced with each of the respective sensors via suitable hardware. For example, in one embodiment, patient monitoring subsystem  108  is connected to the EKG sensors via an EKG system  122 . In one embodiment, patient monitoring subsystem  108  receives information based on a sensed condition by the implanted treatment device  102  via communication channel  124 . Communication channel  124  can be over any suitable communications media, including via conductive material, via electromagnetic radiation (heat, light, radio, etc.), via mechanical signaling such as ultrasonic transduction, and the like. In one embodiment, communication channel  124  is common with communication channel  126  between implanted device  102  and device configurator sub-system  110 . 
     Patient monitoring subsystem  108  monitors one or more of these sensors, or other suitable sensors (and supplies electrical power, air pressure, or other appropriate enablement needed to facilitate operation of the sensors), converts each sensor&#39;s reading into a form suitable for reading by the CPU, and communicates the sensor information to the CPU according to the established communications protocol. 
     Device configurator sub-system  110  includes hardware and/or software for communicating with implanted treatment device  102  over communication channel  126 . Communications over channel  126  include device configurator sub-system  110  reading status, data, and other relevant information originating in the treatment device  102 , and transmitting configuration information, calibration, or instructions to the treatment device  102 . Communication channel  126  can be over any suitable communications media, including via conductive material, via electromagnetic radiation (heat, light, radio, etc.), via mechanical signaling such as ultrasonic transduction, and the like. 
     Operator interface  112  permits a human user of system  100 , such as a clinician, to observe the operation of system  100 , including monitoring the patient&#39;s sensed condition, the activity of implanted treatment device  102 , and the progress of programming the treatment device  102 . In one embodiment, information is displayed to the clinician in a graphical format, such as time-based rolling plots of selected patient conditions, together with the progress of the dose-response testing. Such a display, which includes providing stored historic dose-response data of the patient, can enable the clinician to readily identify any particular trends in the dose-response test results. 
     In a preferred type of embodiment, operator interface  112  also enables the clinician to manually control the dose-response testing, determination of operating point for implanted device  102 , and/or the programming of the implanted device  102  to a selectable extent. In one example embodiment of this type, an operator has the option of running the system  100  in a fully automatic mode, or exercising some level of control over patient monitoring, dose-response testing, analysis of the dose-response testing results, or configuring of the implanted device  102 . In one embodiment, operator interface  112  is configured to accept manually inputted data representing a condition of the patient for incorporation into the analysis of the dose-response testing. 
     Operator interface  112  can be integrated closely with one or more sub-systems of system  100  such that CPU  106  controls operator interface  112 . Alternatively, operator interface  112  can itself be a separate device that merely exchanges data with CPU  106 . In this latter embodiment, operator interface  112  can be implemented in a personal computer (PC) running an application program that enables the PC to interface with CPU  106  and facilitate the user display and inputs. In one embodiment, operator interface  112  can be interfaced with CPU  106  over a computer network. Preferably, operator interface  112  is situated remotely from the patient to minimize the undesirable effect on the accuracy of measurement of the patient&#39;s condition resulting from interaction between the clinician and patient. 
       FIG. 2  illustrates an exemplary arrangement of components of a programming system  200  and their interface with one another and with a hypertension treatment device  202  implanted in a patient  204 . Programming system  200  includes a programmer  206 , which has processor  208  interfaced with communications circuit  210  via interface  209  between processor  208  and communications circuit  210  can be a PCI bus, I2C bus, or any other suitable interface known in the art. Processor  208  includes at least a CPU core and memory MEM. Communications circuit  210  includes transceiver circuitry coupled with an antenna  212  for communicating with communications circuit  214  of implanted hypertension treatment device  202 . 
     Programming system  202  further includes heart rate monitor  216  and hemodynamic monitor  218 . As illustrated in  FIG. 2 , these components are interfaced with processor  208  via bus  222 , which can be the same interface as interface  209 , or another suitable interface known in the art. Heart rate monitor  216  and hemodynamic monitor  218  are each operatively interfaced with the patient  204  to measure the patient&#39;s physiological conditions, as represented by the double-dashed lines and indicated at  204 ′. 
     Operator interface  220  is operatively coupled with processor  208  via interface bus  224 . Interface bus  224  can be the same interface as interface  222 , or can be another suitable interface. 
     Implanted hypertension treatment device  202  includes CPU  226  that is configured to control the operation of the device. CPU  226  can detect the need for applying electrotherapy via patient monitoring circuitry that includes blood pressure measuring circuit  228  interfaced with implanted blood pressure sensor  230 , and via pulse measuring circuit  232  interfaced with implanted pulse sensor  234 . CPU  226  is further configured to administer the electrotherapy via electrotherapy circuit  236  and electrodes  238 . 
     Heart rate monitor  216  and hemodynamic monitor  218  are interfaced with the exterior of the patient. In another type of embodiment, heart rate monitor  216  and hemodynamic monitor  218  are implanted in the patient and include data gathering and communication electronics for acquiring the patient&#39;s physiological conditions and transmitting data representing the same to CPU  208  via communications circuit  210 . In this type of embodiment, heart rate monitor  216  and hemodynamic monitor  218  can either operate independently of implanted hypertension treatment device  202 , or can communicate information to the treatment device  202 . 
     In operation, programming system  200 , according to one embodiment, can verify that heart rate monitor  216  and hemodynamic monitor  218  provide substantially similar indicia of the patient&#39;s physiological state as provided via blood pressure measuring circuit  228  and pulse measuring circuit  232 . If these indicia are dissimilar to an unacceptable degree, programming system  200  can calibrate the measuring circuits  228  and  232  of implanted device  202 , or the implanted device&#39;s interpretation of the measurement data generated by the measuring circuits  228  and  232 . Programming system  200  is further configured to conduct a set of dose-response tests by commanding implanted device  202  to systematically vary the therapy dosage over time, while monitoring the effect of the therapy on the patient&#39;s physiology via at least one of heart rate monitor  216 , hemodynamic monitor  218 , blood pressure measuring circuit  228 , and/or pulse measuring circuit  232 . As will be discussed in detail below, one aspect of the invention is directed to the use of pulse, or heart rate measurement in lieu of hemodynamic or blood pressure measurement to reduce the time needed to conduct each dose-response test. 
       FIGS. 3A-3D  illustrate various examples of measurement arrangements for monitoring the patient&#39;s physiology during the dose-response testing. In  FIG. 3A , implanted hypertension treatment device (IHTD)  300  is situated on the internal side of patient boundary  302 . Programmer  304  is communicatively coupled with IHTD  300 . Heart rate monitor (HRM)  306  and hemodynamic monitoring system (HMS)  308  are operably coupled to programmer  304  and, during system operation, are physically engaged with the patient&#39;s exterior. In one embodiment, one or both of HRM  306  and HMS  308  are integrated with the programmer  304 . In another embodiment, at least one of HRM  306  and HMS  308  are separate devices electrically interconnected with programmer  304 . 
     In  FIG. 3B , heart rate monitor HRM  310  and hemodynamic monitoring system  312  are implanted in the patient as part of IHTD  300 . Programmer  304  receives patient physiology information from one or both of HRM  310  and/or HMS  312 , which information is collected and analyzed during the dose-response testing. In this embodiment, additional external heart rate monitoring or hemodynamic monitoring is avoided. 
     By contrast, the example arrangement of  FIG. 3C  has external heart rate monitoring and hemodynamic monitoring facilitated respectively by HRM  306  and HMS  308 . This arrangement is similar to the arrangement described above with reference to  FIG. 2 . One advantage of having available externally-measured physiology information in addition to 30 internally-measured physiology information by the IHTD is the externally-measured condition of the patient can be used by the programmer  304  verify accuracy of the internally-measured condition. In one embodiment, programmer  304  calibrates the measurements of internal HRM  310  and HMS  312 . 
     In another embodiment, programmer  304  configures IHTD  300  to supply therapy dosage based on the internally-measured physiology data by HRM  310  and HMS  312  irrespective of whether these measurements are accurate relative to the externally-measured physiologic condition of the patient by external HRM  306  and HMS  308 . The calibration of IHTD  300  achieved through the dose response testing carried out by programmer  304  correlates the physiology information obtained from internal measurements with those obtained from the external measurements. Assuming, for example, that the external measurements obtained by HRM  306  and HMS  308  are an accurate representation of the patient&#39;s actual condition, programmer  304  will establish the appropriate therapy dosage based on the externally-obtained physiology information. After calibration, the IHTD  300  will administer the established therapy dosage according to physiologic measurements made by internal monitors HRM  310  and HMS  312 , which represent the patient&#39;s actual condition  15  to IHTD  300 . 
     The example arrangement illustrated in  FIG. 3D  is similar to the arrangement of  FIG. 3C  in that programmer  304  gathers patient physiology data from HRM  306  and HMS  308  that are separate from HRM  310  and HMS  312  integral to IHTD  300 . However, in the arrangement of  FIG. 3D , HRM  306  and HMS  308  are implanted in the patient and communicatively coupled to programmer  304  through patient boundary  302 . 
     Persons skilled in the relevant arts will appreciate that variations and combinations of the example embodiments of  FIGS. 3A-3D  are all within the spirit of the invention. Thus, referring to  FIGS. 3C and 3D  for example, HRM  306  can be implanted in the patient as depicted in  FIG. 3D , while HMS  308  can be external to the patient, as depicted in  FIG. 3C . 25 Persons skilled in the art will also appreciate that the requisite physiologic information for assessing the patient&#39;s actual condition can be obtained with only a hemodynamic monitoring system such as HMS  308 , i.e., without heart rate monitoring. Thus, the arrangements in  FIGS. 3A-3D  and their variants and combinations having only HMS  308 , HMS  312 , or both, (without HRM  306  and/or HRM  310 ) are all within the spirit of the invention. Alternatively, as described below, certain embodiments of the invention can benefit from heart rate monitoring in addition to, and sometimes in lieu of, hemodynamic monitoring alone. 
       FIG. 4  is a schematic diagram illustrating one embodiment of a programmer  400  for configuring an implanted hypertension treatment device. Programmer  400  can be used with patient monitoring devices or hardware to establish a programming system such as system  100  ( FIG. 1 ) or system  200  ( FIG. 2 ). Programmer  400  can also be used as an embodiment of programmer  304  ( FIGS. 3A-3D ). Components of programmer  400  include a CPU  402 , which includes a processor core such as digital signal processor (DSP)  408 , instruction memory space  404 , and data storage space  406 . In operation, programmer  400  is interfaced with patient monitoring and other equipment via interface multiplexer (MUX)  410 . MUX  410  selectively supplies patient monitoring signaling to analog-to-digital converter (AID)  412 , which feeds CPU-readable data to CPU  402 . MUX  410  can be digitally controlled directly from CPU  402 . 
     Programmer  400  also includes a wireless communications transceiver  414  for facilitating communications with the implanted device. An internal communications bus  418  facilitates data exchange between CPU  402  and the other components of programmer  400 . Communications bus  418  can have any suitable bus architecture, as known by persons skilled in the art, including, but not limited to, PCI, SCSI, CAN, I 2 C, USB, and the like. 
     As depicted in  FIG. 4 , programmer  400  is interfaced with a user interface  416 . Preferably, user interface  416  is remote from programmer  400 . Positioning a clinician operating programmer  400  remotely from the patient during the dose-response testing can realize an advantage by eliminating inadvertent conversations between the clinician and the patient, which are known to adversely impact the accuracy of hemodynamic measurements. To this end, in a preferred embodiment, user interface  416  is communicatively coupled with CPU  402  via interface  420  that is suitable for communications over a relatively larger distance than interface  418 . In one such embodiment, interface  420  is an Ethernet or a wireless IEEE 802.11G Wi-Fi-type interface that facilitates operator control of programmer  400  from a remote location, such as a different room. In one embodiment, interface  420  is operatively coupled with bus  418  via network interface controller (NIC)  422 . 
     One aspect of the invention is directed to a method of automatically configuring, or programming, an implanted hypertension treatment device. In one embodiment, the method can be performed without clinician intervention. Optionally, a clinician can monitor the progress of the device configuring process, and intervene if appropriate. One motivation for conducting such programming or configuring is to discover the optimal settings for the implanted hypertension treatment device. In an embodiment in which the implanted device utilizes electrotherapy to regulate blood pressure in the patient, for example, it is desirable for the device to consume a minimal amount of electrical energy to preserve battery life, while ensuring an effective and reliable degree of therapeutic effectiveness, or performance, with a safety margin. According to one type of configuration algorithm, the dose-response testing is conducted such that the therapy dosage administered by the implanted device is incrementally varied according to a predefined sequence, while the effect of the therapy is monitored. The programming system analyzes the results of the tests, and determines the proper settings for various adjustable parameters of the implanted device. 
       FIG. 5A  illustrates a routine  500  according to one embodiment of the invention for conducting dose-response testing to establish desired settings or configuration of an implanted hypertension treatment device. A programming system, such as system  100  ( FIG. 1 ) or system  200  ( FIG. 2 ) is configured to begin the routine according to a default set of routine parameters, such as initial dosage level, step changes in dosage level, settling time, hemodynamic measurement duration, and hypertension treatment effectiveness assessment criteria. At  501 , the programming system measures the patient&#39;s baseline hemodynamic condition (i.e., without the administration of therapy by the implanted device). At  502 , the system issues a command to the implanted device that instructs the device to administer the first level of therapy. Because the physiologic response of the patient to hypertension therapy may not be immediate, at  504 , the system waits for a settling period until the beginning of the measurement window. During this settling period, the hemodynamic measurement in the patient should approach a steady state. Depending on the patient, administered therapy dosage level, type of therapy, type of physiologic monitoring, and other such factors, the settling period can range from several seconds to 5 minutes or more before a reliable measurement can be made for assessing the effectiveness of the administered dosage. 
     At  506 , the system measures the patient&#39;s hemodynamic condition over a monitoring time duration. The monitoring time duration can also range from several seconds to 5 minutes or more. In one configuration, the total time between administration of therapy is as little as 15 seconds. In another configuration, the total time is at least a minute. Persons skilled in the art will appreciate that this time can be suitably configured as required to obtain accurate and reliable measurements of the patient&#39;s status. Whichever settings are configured for the settling time or measurement period, the automated system is able to consistently and accurately follow the timing protocol for each dose-response test, thereby achieving an improved repeatability over manually-performed measurements. Measurement of the hemodynamic condition includes, but is not limited to, measurement of the patient&#39;s pulse rate, systolic pressure, diastolic pressure, mean arterial pressure, pulse pressure, blood oxygenation, electrocardiogram information, cardiovascular resistance, sympathetic/parasympathetic tone, and the like. 
     At  508 , the programming system analyzes the effectiveness of the therapy based on the pre- and post-therapy hemodynamic condition measurements made. The analysis can be further based on a comparison between actual results and expected results. In one embodiment, the programming system will notify the clinician whenever a greater-than-anticipated difference between the actual and expected results is detected. At  510 , the system determines whether to continue the dose-response testing. If testing is to continue, the system computes or selects the next therapy dosage for the implanted device to apply, and the process is repeated beginning at  502 . Otherwise, if the testing is complete, the system finalizes the programming of the implanted device, and exits from the routine. 
     The programming routine illustrated by the flow diagram of  FIG. 5B  is a variation of method  500  in which the settling time delay and/or the measuring window can be automatically and dynamically adjusted. After instructing the implanted device to administer a selected therapy dose at  522 , the programming system begins the monitoring the patient&#39;s hemodynamic condition relatively soon (e.g. within several seconds), as indicated at  524 . During the monitoring, at  526 , the programming system begins building a database of patient condition measurements over time, with dosage and timestamp information included in the records. 
     Based on the information gathered and analyzed, the system can also dynamically adjust the default measuring duration and settling time while executing a programming routine, as indicated at  528 . For example, in a programming system that utilizes both real time (i.e., continuous) and non-real time (i.e., discontinuous) hemodynamic measurements according to one embodiment, the real time measuring begins at  524  immediately after therapy administered. Analyzed real time hemodynamic data as a function of time can indicate an appropriate moment for making a non-real time measurement. Thus, the physiologic settling time delay for the non-real time measurement can be automatically varied for each dose-response test to coincide with the actual time when the patient&#39;s condition has stabilized. Persons skilled in the art will recognize that the default measuring duration can be dynamically adjusted in systems where only real time measurement is employed. 
     As part of the measurement data analysis at  528 , the programming system evaluates the shape of the time-based curve generated. This type of analysis permits estimation and/or extrapolation of data, and in one embodiment, is used by the system to shorten the measurement window. For example, if the time rate of change of the patient&#39;s monitored blood pressure is not as steep as required for an effective therapy dosage, the system can conclude that a greater dose is needed, and bypass the remaining measurement window, thereby expediting the overall routine. The data collection can also include measurements made over multiple dose-response tests. Thus, data curves can be generated and evaluated to analyze the patient&#39;s physiological responsiveness as a function of therapy dosage. 
     At  530 , the system obtains any additional hemodynamic measurements needed to compute the assessment of the effectiveness of the administered therapy. Based on the assessment, at  532 , the system determines whether or not to continue the dose-response testing, and which settings to apply to the implanted device in the next loop if testing is to continue. 
       FIGS. 6A and 6B  are graphs illustrating an exemplary dose-response in a patient. The curve in  FIG. 6A  represents measurements of the patient&#39;s stabilized systolic blood pressure, while the curve in  FIG. 6B  represents the measured heart rate of the patient. Both curves are functions of the dosage applied by an electrotherapy device. The graphs of  FIGS. 6A and 6B  suggests a significant correlation between the heart rate and blood pressure. Based on this physiologic phenomenon, the heart rate measurement, obtainable over a relatively shorter measurement window than the blood pressure measurement, can be used to approximate or predict the patient&#39;s blood pressure. 
     Taking advantage of the correlation between the heart rate and blood pressure, a method  700  of configuring an implanted device according to one embodiment is illustrated in  FIG. 7 . At  702 , the programming system initiates the dose-response testing and configuring loop by initiating hypertension therapy administration by the implanted device. At  704 , soon after the therapy has been administered, the system continuously monitors the patient&#39;s heart rate. In one embodiment, the system is configured to automatically test whether the heart rate is within a safe range. If it is outside the safe range, the clinician is notified and the dose-response testing is suspended or terminated either automatically or by the clinician. Related embodiments include measuring or determining one or more other factors representing heartbeat information including, but not limited to, heart rate stability or instability, sympathetic or parasympathetic tone, heart rate variability, and the like. 
     In another related embodiment, the system processes the heart rate curve as a function of time to predict the time needed for settling of the hemodynamic condition to be measured discontinuously in non-real time. Similarly, one embodiment analyzes the heart rate curve to establish the measuring window for other hemodynamic measurements to follow. 
     At  706 , the programming system processes at least a portion of the collected heart rate information to determine if the administered dosage caused a significant effect on the heart rate. The heart rate analysis can be performed relatively quickly (i.e. on the order of several seconds). If the effect is marginal, the system concludes that the dosage is either too small to have any effect on the patient, or that the most recently administered dosage is not significantly different from the preceding dosage, and returns to  702  to repeat the loop with a different dosage designed to elicit the targeted effect on the patient. In this manner, the system avoids spending time on further hemodynamic monitoring (which could take more than one minute to complete) and analysis of a patient condition that is unlikely to be desirable. If, on the other hand, the effect on the heart rate is measured to be significant, the system will commit to further hemodynamic condition measurement, analysis, and device configuring as indicated at steps  708 ,  710 , and  712 . 
       FIG. 8  is a diagram illustrating a method of configuring an implanted electrotherapy-type hypertension treatment device that takes advantage of the correlation between heart rate information and blood pressure, and utilizes interpolative and predictive analysis techniques. In  FIG. 8 , the vertical axis generally represents the patient&#39;s physiologic conditions including heart rate HR and systolic blood pressure BP. The horizontal axis represents the electrotherapy dosage. The Target Range is the desired operating point of the implanted device (i.e. the dosage at which the patient&#39;s blood pressure is controlled to be within a desirable range). In one embodiment, the programming system first conducts a series of relatively short-duration dose-response tests, measuring only the patient&#39;s heart rate. Reference numerals A-I indicate the result set of the heart rate dose-response measurements at corresponding dosages. 
     The programming system analyzes data set A-I to assess the general shape of the curve produced as a function of dosage level. Based on certain features of the curve, the programming system determines at which dosage levels to conduct a series of complete hemodynamic measurements. For example, in one embodiment, as illustrated, the first hemodynamic measurement α is conducted at the dosage corresponding to heart rate measurement A. This initial measurement establishes a baseline, relative to which subsequent hemodynamic measurements are planned. The second hemodynamic measurement β is conducted at the dosage corresponding to heart rate measurement F. Heart rate measurement F has been selected according to this exemplary method because it lies at a corner point where the curve slope is approximately −0.5. However, any other suitable criteria for selecting preliminary and subsequent dosage levels is within the spirit of the invention. Because hemodynamic measurement β falls significantly outside and above the Target Range, the programming system selects the dosage corresponding to heart rate measurement H as the third hemodynamic measurement point, producing hemodynamic measurement γ. Measurement γ is only marginally within the Target Range, so the programming system next conducts a hemodynamic measurement at the next lowest dosage corresponding to heart rate measurement G, resulting in hemodynamic measurement δ, which is marginally outside of the Target Range. 
     Next, the system proceeds to interpolate between the last two hemodynamic measurements δ and γ, favoring a dosage closer to the dosage corresponding to hemodynamic measurement γ because it is closer to the center of the Target Range. The result of the interpolation is hemodynamic measurement ε, which is substantially near the center of the Target Range. The dosage level corresponding to hemodynamic measurement ε is the level for which the system will configure the implanted electrotherapy device. This example method of arriving at the final dosage required only five hemodynamic measurements, compared with eight or nine measurements that would have been made if the programming routine had utilized a simpler incremental approach. 
     For a more detailed description of one embodiment of a user interface adaptable for use with the present invention, reference is made to “User Interface for Programming/Monitoring Non-Cardiac Tissue Stimulator Devices,” Ser. No. 60/584,743, filed Jun. 30, 2004, the disclosure of which is hereby incorporated by reference. For a background reference of implantable devices for treating high blood pressure or hypertension by stimulating various nerves and tissue in the body, reference is made to U.S. Pat. No. 3,650,277 (stimulation of carotid sinus nerve), U.S. Pat. No. 5,707,400 (stimulation of vagal nerve), and U.S. Pat. No. 6,522,926 (stimulation of baroreceptors), the disclosure of each of which is hereby incorporated by reference. 
     Various modifications to the method may be apparent to one of skill in the art upon reading this disclosure. The above is not contemplated to limit the scope of the present invention, which is limited only by the claims below.