SYSTEM GUIDE TELIGEN™ 100 IMPLANTABLE CARDIOVERTER HIGH ENERGY DEFIBRILLATOR REF E102, E110 CAUTION: Federal law restricts this device to sale by or on the order of a physician trained or experienced in device implant and follow-up procedures.
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ABOUT THIS MANUAL Boston Scientific Corporation acquired Guidant Corporation in April 2006. During our transition period, you may see both the Boston Scientific and Guidant names on product and patient material. As we work through the transition, we will continue to offer doctors and their patients technologically advanced and high quality medical devices and therapies. The text conventions discussed below are used throughout this manual.
AFib: AFR: AGC: AIVR: AT: ATP: ATR: AV: BCL: BOL: CPR: ECG: DFT: EAS: EF: EGM: EMI: EP: FCC: HE: IBP: IC: ICD: LRL: MI: MPR: MRI: MSR: MTR: NSR: PAC: PAT: PES: PMT: PRM: PSA: PVARP: PVC: RADAR: RF: RV: RVRP: SCD: Atrial Fibrillation Atrial Flutter Response Automatic Gain Control Accelerated Idioventricular Rhythm Atrial Tachycardia Antitachycardia Pacing Atrial Tachy Response Atrioventricular Burst Cycle Length Beginning of Life Cardiopulmonary Resuscitation Electrocardiogram Defibrillation Threshold Elect
SRD: SVT: TARP: TENS: V: VFib: VF: VRP: VRR: VT: VTR: Sustained Rate Duration Supraventricular Tachycardia Total Atrial Refractory Period Transcutaneous Electrical Nerve Stimulation Ventricular Ventricular Fibrillation Ventricular Fibrillation Ventricular Refractory Period Ventricular Rate Regulation Ventricular Tachycardia Ventricular Tachycardia Response - DRAFT -
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CONTENTS INFORMATION FOR USE ................................................................................................. CHAPTER 1 1-1 New or Enhanced Features................................................................................................ 1-3 Device Description.............................................................................................................. 1-4 Related Information .......................................................................................
Patient Counseling Information ........................................................................................ Patient Handbook ...................................................................................................... 1-27 1-28 USING THE PROGRAMMER/RECORDER/MONITOR..................................................... CHAPTER 2 2-1 ZOOM LATITUDE Programming System ........................................................................... 2-2 Indications-Based Programming (IBP) ..
Backup Defibrillator.................................................................................................... Programming the Device Safety Tachy Mode............................................................ 2-19 2-20 TACHYARRHYTHMIA DETECTION.................................................................................. CHAPTER 3 3-1 Device Mode....................................................................................................................... Ventricular Tachy Mode.
Ventricular Shock Therapy and Parameters..................................................................... Ventricular Shock Vector............................................................................................ Ventricular Shock Energy........................................................................................... Charge Time .............................................................................................................. Waveform Polarity.............................
AV Delay........................................................................................................................... Paced AV Delay ......................................................................................................... Sensed AV Delay ....................................................................................................... AV Search+ ................................................................................................................
ELECTROPHYSIOLOGIC TESTING................................................................................. CHAPTER 8 8-1 EP Test Features ................................................................................................................ Temporary EP Mode .................................................................................................... Backup Ventricular Pacing During Atrial EP Testing .................................................... EP Test Screen ....................
Magnet Feature.......................................................................................................... 10-5 Explantation...................................................................................................................... 10-8 PROGRAMMABLE OPTIONS........................................................................................... APPENDIX A A-1 PACEMAKER INTERACTION ...........................................................................................
CLINICAL STUDY - VITALITY........................................................................................... APPENDIX E E-1 Clinical Study Populations .................................................................................................. E-1 Chronic Implant Study - VITALITY...................................................................................... E-1 Acute Study - VITALITY...................................................................................................
1-1 INFORMATION FOR USE CHAPTER 1 This chapter contains the following topics: • "New or Enhanced Features" on page 1-3 • "Device Description" on page 1-4 • "Related Information" on page 1-6 • "Indications and Usage" on page 1-6 • "Contraindications" on page 1-6 • "Warnings" on page 1-7 • "Precautions" on page 1-8 • "Potential Adverse Events" on page 1-18 • "Mechanical Specifications" on page 1-19 • "Lead Connections" on page 1-20 • "Items Included in Package" on page 1-21 • "Symbols
1-2 INFORMATION FOR USE • "Patient Counseling Information" on page 1-27 - DRAFT -
1-3 NEW OR ENHANCED FEATURES These pulse generator systems include additional features as compared to previous products. Ease of Use • • ZOOMVIEW Programmer Software: the new user interface offers the following benefits: – Clinical focus—features such as patient diagnostic trends and indications-based programming emphasize the patient’s clinical condition over device status and parameters.
1-4 INFORMATION FOR USE DEVICE DESCRIPTION Brady Therapy • AV Search +: this feature is designed to reduce unnecessary RV pacing for patients with intact or intermittent AV conduction by allowing intrinsic AV conduction beyond the programmed AV delay during episodes of normal AV nodal function—an enhanced version of AV Search Hysteresis.
INFORMATION FOR USE DEVICE DESCRIPTION • 1-5 The choice of multiple shock vectors: – Distal shock electrode to proximal shock electrode and pulse generator case (TRIAD electrode system) – Distal shock electrode to proximal shock electrode (RV Coil to RA Coil) – Distal shock electrode to pulse generator case (RV Coil to Can) Leads The pulse generator has independently programmable outputs and accepts the following leads: • One IS-11 atrial lead • One DF-1/IS-12 cardioversion/defibrillation lead
1-6 INFORMATION FOR USE RELATED INFORMATION RELATED INFORMATION Refer to the lead’s instruction manual for implant information, general warnings and precautions, indications, contraindications, and technical specifications. Read this material carefully for implant procedure instructions specific to the chosen lead configurations. The Physician’s Technical Manual is packaged with the pulse generator. It provides the technical information needed at implant.
INFORMATION FOR USE WARNINGS 1-7 WARNINGS General • Labeling knowledge. Read this manual thoroughly before implanting the pulse generator to avoid damage to the system. Such damage can result in patient injury or death. • Avoid shock during handling. Program the pulse generator Tachy Mode(s) to Off during implant, explant, or postmortem procedures to avoid inadvertent high voltage shocks. • Backup defibrillation protection.
1-8 INFORMATION FOR USE PRECAUTIONS Implant Related • Do not kink leads. Kinking leads may cause additional stress on the leads, possibly resulting in lead fracture. • Separate pulse generator. Do not use this pulse generator with another pulse generator. This combination could cause pulse generator interaction, resulting in patient injury or a lack of therapy delivery. PRECAUTIONS Clinical Considerations • Pacemaker-mediated tachycardia (PMT).
INFORMATION FOR USE PRECAUTIONS 1-9 Implantation and Device Programming • Lead system. Do not use any lead with this device without first verifying connector compatibility. Using incompatible leads can damage the connector and/or result in potential adverse consequences, such as undersensing of cardiac activity or failure to deliver necessary therapy. • Telemetry wand. Make sure the telemetry wand is connected to the programmer and that it is available throughout the session.
1-10 INFORMATION FOR USE PRECAUTIONS • Defibrillation power surge. Defibrillation that causes a power surge exceeding 360 watt-seconds can damage the pulse generator system. • Programming for supraventricular tachyarrhythmias (SVTs). Determine if the device and programmable options are appropriate for patients with SVTs because SVTs can initiate unwanted device therapy. • Ventricular refractory periods (VRPs) in adaptive-rate pacing. Adaptive-rate pacing is not limited by refractory periods.
INFORMATION FOR USE PRECAUTIONS 1-11 • Atrial oversensing. For dual-chamber models, take care to ensure that artifacts from the ventricles are not present on the atrial channel, or atrial oversensing may result. If ventricular artifacts are present in the atrial channel, the atrial lead may need to be repositioned to minimize its interaction. • Defibrillation lead impedance. Never implant the device with a lead system that has less than 15 Ω total shock lead impedance. Device damage may result.
1-12 INFORMATION FOR USE PRECAUTIONS Environmental and Medical Therapy Hazards • • Avoid electromagnetic interference (EMI). Advise patients to avoid sources of EMI because EMI may cause the pulse generator to deliver inappropriate therapy or inhibit appropriate therapy.
INFORMATION FOR USE PRECAUTIONS • 1-13 Transcutaneous electrical nerve stimulation (TENS). TENS may interfere with pulse generator function. If necessary, the following measures may reduce interference: 1. Place the TENS electrodes as close to each other as possible and as far from the pulse generator and lead system as possible. 2. Monitor cardiac activity during TENS use. For additional information, contact Technical Services at the number shown on the back cover of this manual. • Electrocautery.
1-14 INFORMATION FOR USE PRECAUTIONS • Ionizing radiation therapy. Ionizing radiation therapy may adversely affect device operation. During ionizing radiation therapy (e.g., radioactive cobalt, linear accelerators, and betatrons), the pulse generator must be shielded with a radiation-resistive material, regardless of the distance of the device to the radiation beam. Do not project the radiation port directly at the device.
INFORMATION FOR USE PRECAUTIONS • 1-15 Radio frequency ablation. Exercise caution when performing radio frequency ablation procedures in device patients. If the pulse generator Tachy Mode is programmed to Monitor + Therapy during the procedure, the device may inappropriately declare a tachycardia episode and deliver therapy. Pacing therapy may also be inhibited unless the device is programmed to Electrocautery mode.
1-16 INFORMATION FOR USE PRECAUTIONS • Radio frequency (RF) interference. RF signals from devices that operate at frequencies near that of the pulse generator may interrupt ZIP telemetry while interrogating or programming the pulse generator. This RF interference can be reduced by increasing the distance between the interfering device and the PRM and pulse generator.
INFORMATION FOR USE PRECAUTIONS • 1-17 Cellular phones. Advise patients to hold cellular phones to the ear opposite the side of the implanted device. Patients should not carry a cellular phone that is turned on in a breast pocket or on a belt within 15 cm (6 inches) of the implanted device since some cellular phones may cause the pulse generator to deliver inappropriate therapy or inhibit appropriate therapy. Follow-up Testing • Conversion testing.
1-18 INFORMATION FOR USE POTENTIAL ADVERSE EVENTS POTENTIAL ADVERSE EVENTS Based on the literature and on pulse generator implant experience, the following alphabetical list includes the possible adverse events associated with implantation of a pulse generator system: • Air embolism • Allergic reaction • Bleeding • Cardiac tamponade • Chronic nerve damage • Component failure • Conductor coil fracture • Death • Elevated thresholds • Erosion • Excessive fibrotic tissue growth • Extrac
INFORMATION FOR USE MECHANICAL SPECIFICATIONS • 1-19 Myocardial trauma (e.g., cardiac perforation, irritability, injury) • Myopotential sensing • Oversensing/undersensing • Pacemaker-mediated tachycardia (PMT) (Applies to dual-chamber devices only.
1-20 INFORMATION FOR USE LEAD CONNECTIONS Table 1-1. Mechanical Specifications Model Dimensions W x H x D (cm) Volume (cm3) Mass (g) Connector Type (RV) Case Electrode Surface Area (mm²) E102 (VR) 6.17 x 7.45 x 0.99 31.5 72.0 IS-1/DF-1 6670 E110 (DR) 6.17 x 7.45 x 0.99 31.5 72.0 IS-1/DF-1 6670 Models include ZIP telemetry with a nominal RF frequency of 916.5 MHz.
INFORMATION FOR USE ITEMS INCLUDED IN PACKAGE 1-21 NOTE: The pulse generator case is used as a defibrillating electrode unless the pulse generator has been programmed to the Distal Coil to Proximal Coil (or “Cold Can”) Shock Vector. ITEMS INCLUDED IN PACKAGE The following items are included with the pulse generator: • One torque wrench • Product literature • One patient data disk NOTE: Accessories (e.g., wrenches) are intended for one-time use only. They should not be resterilized or reused.
1-22 INFORMATION FOR USE CHARACTERISTICS AS SHIPPED Table 1-2. Symbols on packaging (continued) Description Symbol Lot number Date of manufacture Non-ionizing electromagnetic radiation Sterilized using ethylene oxide Do not reuse Dangerous voltage Consult instructions for use Temperature limitation Wand placement indicator for interrogation Opening instruction CHARACTERISTICS AS SHIPPED Refer to the table for pulse generator settings at shipment (Table 1-3 on page 1-22). Table 1-3.
INFORMATION FOR USE X-RAY IDENTIFIER Table 1-3. 1-23 Characteristics as shipped (continued) Parameter Setting Pacing Therapy available DDDR (DR models) VVIR (VR models) Sensor Accelerometer (MV for respiratory rate trend) Pace/Sense Configuration RA: BI/BI (DR models) Pace/Sense Configuration RV: BI/BI The pulse generator is shipped in a power-saving Storage mode to extend its shelf life.
1-24 INFORMATION FOR USE FEDERAL COMMUNICATIONS COMMISSION (FCC) The x-ray identifier is embedded in the header of the device at the approximate location (Figure 1-3 on page 1-24). Header X-Ray Identifier Pulse Generator Case Figure 1-3. X-ray identifier For information on identifying the device via the PRM, refer to the PRM operator’s manual. The pulse generator model number is stored in device memory and is shown on the PRM summary screen once the pulse generator is interrogated.
1-25 INFORMATION FOR USE PULSE GENERATOR LONGEVITY PULSE GENERATOR LONGEVITY Based on simulated studies, it is anticipated that these pulse generators have average longevity to explant as shown below. The longevity expectations, which account for the energy used during manufacture and storage, apply at the conditions shown in the table along with the following: • Assumes 60 ppm LRL, ventricular and atrial settings of 2.5 V pacing pulse amplitude and 0.4 ms pacing pulse width; RA Impedance 500 Ω.
1-26 INFORMATION FOR USE WARRANTY INFORMATION • Charging frequency Longevity is also reduced in the following circumstances: • With a decrease in pacing impedance • When Patient Triggered Monitor is programmed to On • For models with ZIP wandless telemetry, one hour of additional telemetry reduces longevity by approximately 7 days.
INFORMATION FOR USE PATIENT COUNSELING INFORMATION 1-27 Refer to Boston Scientific’s CRM Product Performance Report on www.bostonscientific.com for more information about device performance, including the types and rates of malfunctions that these devices have experienced historically. While historical data may not be predictive of future device performance, such data can provide important context for understanding the overall reliability of these types of products.
1-28 INFORMATION FOR USE PATIENT COUNSELING INFORMATION • It is Boston Scientific’s intent to provide implantable devices of high quality and reliability. However, these devices may exhibit malfunctions that may result in lost or compromised ability to deliver therapy.
2-1 USING THE PROGRAMMER/RECORDER/MONITOR CHAPTER 2 This chapter contains the following topics: • "ZOOM LATITUDE Programming System" on page 2-2 • "Indications-Based Programming (IBP)" on page 2-2 • "Manual Programming" on page 2-5 • "Software Terminology and Navigation" on page 2-6 • "Data Management" on page 2-11 • "Communicating with the Pulse Generator" on page 2-12 • "DIVERT THERAPY" on page 2-17 • "STAT SHOCK" on page 2-17 • "STAT PACE" on page 2-18 • "Safety Mode" on page 2-19 -
2-2 USING THE PROGRAMMER/RECORDER/MONITOR ZOOM LATITUDE PROGRAMMING SYSTEM ZOOM LATITUDE PROGRAMMING SYSTEM The ZOOM LATITUDE Programming System is the external portion of the pulse generator system and includes: • Model 3120 Programmer/Recorder/Monitor (PRM) • Model 2868 ZOOMVIEW Software Application • Model 6577 Accessory Telemetry Wand The ZOOMVIEW software provides advanced device programming and patient monitoring technology.
USING THE PROGRAMMER/RECORDER/MONITOR INDICATIONS-BASED PROGRAMMING (IBP) Figure 2-1. 2-3 Indications-based Programming screen Indications are clustered in general categories as illustrated above. The intent for each category of indications is described below: • • Sinus Node: – If Normal is selected, the intent is to provide RV pacing when necessary. – If Chronotropically Incompetent is selected, the intent is to provide rate-adaptive pacing.
2-4 USING THE PROGRAMMER/RECORDER/MONITOR INDICATIONS-BASED PROGRAMMING (IBP) • • Atrial Arrhythmias – If Paroxysmal/Persistent is selected, the intent is to avoid tracking atrial arrhythmias by using dual-chamber pacing mode with ATR Mode Switch. – If Permanent/Chronic AF is selected, the intent is to provide rate adaptive RV pacing.
USING THE PROGRAMMER/RECORDER/MONITOR MANUAL PROGRAMMING 2-5 NOTE: You must view the settings before you can program them. Selecting the View Recommended Settings button allows you to view the settings that are recommended based on the indications that you selected. Viewing the recommended settings does not overwrite any pending (i.e., not yet programmed) parameter changes. You must choose to program or reject the recommended settings after viewing them.
2-6 USING THE PROGRAMMER/RECORDER/MONITOR SOFTWARE TERMINOLOGY AND NAVIGATION for specific manual programming information and instructions. Refer to "Programmable Options" on page A-1 for detailed listings of available settings. SOFTWARE TERMINOLOGY AND NAVIGATION This section provides an overview of the PRM system. Main Screen The main PRM screen is shown below, followed by a description of the components (Figure 2-3 on page 2-6).
USING THE PROGRAMMER/RECORDER/MONITOR SOFTWARE TERMINOLOGY AND NAVIGATION 2-7 Patient Data Disk—indicates that the PRM is displaying stored data from a patient data disk. Demo Mode—indicates that the PRM is displaying sample data and operating in demonstration mode. ECG/EGM Display The ECG area of the screen shows real-time status information about the patient and the pulse generator.
2-8 USING THE PROGRAMMER/RECORDER/MONITOR SOFTWARE TERMINOLOGY AND NAVIGATION Toolbar The toolbar allows you to perform the following tasks: • Select system utilities • Generate reports • Interrogate and program the pulse generator • View pending or programmed changes • View attentions and warnings • End your PRM session Tabs Tabs allow you to select PRM tasks, such as viewing summary data or programming device settings. Selecting a tab displays the associated screen.
USING THE PROGRAMMER/RECORDER/MONITOR SOFTWARE TERMINOLOGY AND NAVIGATION 2-9 Patient—opens a window with patient information details. Leads—opens a window with details on leads. Battery—opens a window with details on the pulse generator battery. Run—causes the programmer to perform an action. Check—indicates that an option is selected. Event—indicates that an event has occurred. When you view the Trends timeline on the Events tab, event icons display wherever events have occurred.
2-10 USING THE PROGRAMMER/RECORDER/MONITOR SOFTWARE TERMINOLOGY AND NAVIGATION Increment and Decrement Icons Increment—indicates that an associated value can be incremented. Decrement—indicates that an associated value can be decremented. Scroll Icons Scroll Left—indicates that an associated item can be scrolled left. Scroll Right—indicates that an associated item can be scrolled right. Scroll Up—indicates that an associated item can be scrolled up.
USING THE PROGRAMMER/RECORDER/MONITOR DATA MANAGEMENT • 2-11 Yellow—indicates Attention conditions such as the following: – The selected device parameter value is not recommended, but is allowed – Device and patient diagnostic information that should be addressed When a red Warning or yellow Attention button displays in the toolbar, click the button. The Parameter Interactions screen will display, with information about corrective action.
2-12 USING THE PROGRAMMER/RECORDER/MONITOR COMMUNICATING WITH THE PULSE GENERATOR • Save All to Disk—allows you to save information to a disk, including the following: – Therapy history – Programmed parameter values – Trending values – Histogram paced/sensed counters Print You can print PRM reports by using the internal printer, or by connecting to an external printer. To print a report, select the Reports button.
USING THE PROGRAMMER/RECORDER/MONITOR COMMUNICATING WITH THE PULSE GENERATOR • • 2-13 Conduct diagnostic tests including the following: – Pacing impedance tests – Pacing threshold tests – Intrinsic amplitude tests Perform manual capacitor re-form ZIP Telemetry ZIP telemetry is a wandless, two-way RF communication option that allows the PRM system to communicate with some pulse generator models.
2-14 USING THE PROGRAMMER/RECORDER/MONITOR COMMUNICATING WITH THE PULSE GENERATOR 3. Use the PRM to Interrogate the pulse generator. 4. Retain the wand position whenever communication is required. Starting a ZIP Telemetry Session Follow this procedure to begin a ZIP telemetry communication session: 1. Start a wanded telemetry session. Verify that the wand cord is within reach of the pulse generator to enable the use of wanded telemetry should it become necessary. 2.
USING THE PROGRAMMER/RECORDER/MONITOR COMMUNICATING WITH THE PULSE GENERATOR 2-15 In order to meet local communications rules and regulations, ZIP telemetry should not be used when the pulse generator is outside its normal operating temperature of 20°C–43°C (68°F–109°F). The PRM supports communication between two PRMs and two pulse generators at a time, as two independent sessions.
2-16 USING THE PROGRAMMER/RECORDER/MONITOR COMMUNICATING WITH THE PULSE GENERATOR • If event markers and/or EGMs are activated, transmission of the event markers and/or EGMs is interrupted • If a command or other action has been requested, the PRM displays a notification indicating the wand should be placed in range of the pulse generator ZIP telemetry operates consistently with wanded telemetry—no programming step can be completed unless the entire programming command has been received and confirmed
USING THE PROGRAMMER/RECORDER/MONITOR DIVERT THERAPY 2-17 DIVERT THERAPY When the pulse generator is charging to deliver a shock, the shock delivery may be diverted from the patient. If diverted, the shock does not count as one of the total number of shocks that may be delivered during an episode. If redetection occurs and more shock therapy is required, and if more shocks are available in the therapy prescription, the pulse generator will charge again to deliver subsequent shocks.
2-18 USING THE PROGRAMMER/RECORDER/MONITOR STAT PACE 2. Press the STAT SHOCK key. A message window appears with information about the shock and instructions to initiate the shock. 3. To initiate the shock, press the STAT SHOCK key again. A different message window appears indicating that STAT SHOCK is in process. When the shock has been delivered, the message window disappears. 4. Subsequent high-energy STAT SHOCKS may be delivered by repeating the previous steps.
USING THE PROGRAMMER/RECORDER/MONITOR SAFETY MODE 2-19 SAFETY MODE The pulse generator hardware includes a safety core feature. The safety core is intended to provide life-sustaining therapy in the event of specific failures within the pulse generator. If the pulse generator is interrogated while safety core is active, the PRM will indicate that the pulse generator is in Safety Mode. Limited inductive telemetry and some device programming are available during Safety Mode.
2-20 USING THE PROGRAMMER/RECORDER/MONITOR SAFETY MODE the therapy is diverted and detection is inhibited. The magnet must then be removed for 2 seconds in order to allow detection to continue. Programming the Device Safety Tachy Mode In Safety Mode, you can perform the following steps to program the Safety Tachy Mode: 1. Select the Tachy Mode button. The Change Device Mode dialog displays. 2. Click to select the required Safety Tachy Mode setting, either Off or Monitor + Therapy.
3-1 TACHYARRHYTHMIA DETECTION CHAPTER 3 This chapter contains the following topics: • "Device Mode" on page 3-2 • "Rate Sensing" on page 3-3 • "Ventricular Detection" on page 3-6 - DRAFT -
3-2 TACHYARRHYTHMIA DETECTION DEVICE MODE DEVICE MODE The Device Mode allows you to program the device to provide the type of therapy and detection desired. Ventricular Tachy Mode The Ventricular Tachy Mode controls the availability of the detection and therapy functions in the ventricle (Table 3-1 on page 3-2). You can program the Ventricular Tachy Mode to the following modes: Table 3-1. • Off––disables ventricular tachyarrhythmia detection and automatic ventricular therapy delivery.
TACHYARRHYTHMIA DETECTION RATE SENSING Table 3-1. 3-3 Device feature availability in the Ventricular Tachy Mode settings (continued) Ventricular Tachy Mode Device features Off Monitor Only Monitor + Therapy Xd Xd Ventricular EP test Automatic ventricular tachyarrhythmia therapy X a. In order to enable ventricular sensing when the Ventricular Tachy Mode is programmed to Off, you must program the Brady Mode to a mode with ventricular sensing. b.
3-4 TACHYARRHYTHMIA DETECTION RATE SENSING Calculating Rates and Refractory Periods The pulse generator evaluates rate on an interval-by-interval basis. Following a sensed depolarization, a cycle length is measured and compared to the programmed detection parameters. The pulse generator uses refractory periods following paced and sensed intrinsic events; intrinsic events that fall within these periods are ignored for detection purposes.
TACHYARRHYTHMIA DETECTION RATE SENSING Table 3-2. 3-5 Nominal values for Ventricular Rate Threshold configurations (continued) Ventricular Zone Configuration VT-1 Zone VT Zone VF Zone 2 Zones – – 160 bpm 200 bpm 3 Zones 140 bpm 160 bpm 200 bpm Figure 3-1.
3-6 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION • AFib Rate Threshold––program to Off (for Onset/Stability detection enhancement suite) • Atrial Tachyarrhythmia Discrimination––program to Off (for Rhythm ID detection enhancement suite) • Brady Mode––program to Off, VVI, or VVI(R) • Atrial Rate EGM––do not select the atrial trace NOTE: An atrial EP test should not be performed if the atrial lead is programmed to Off.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-7 Ventricular Detection Enhancement Suites One of the following ventricular detection enhancement suites may be programmed to provide specificity beyond Rate and Duration (Table 3-3 on page 3-7): • Rhythm ID • Onset/Stability Detection enhancement suites are not available in the VF zone. Table 3-3.
3-8 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION During Rhythm ID analysis, the pulse generator first determines if the ventricular rate is greater than the atrial rate. If so, therapy will be initiated.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-9 2. The device enables a controlled pacing rate decrease to the programmed Rhythm ID Fallback LRL. During this fallback period, the following occurs: • The device temporarily switches the pacing mode to DDI, VDI, VVI, AAI, or Off (according to the programmed brady mode) and extends the AV delay up to 400 ms. • Rate Smoothing, ATR, hysteresis, and dynamic programming (excluding Dynamic VRP) are suspended. 3.
3-10 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION NOTE: A manual Rhythm ID reference template update should not be commanded immediately after shock therapy. It may take several minutes for irregularities in EGM morphology caused by the shock to subside. Onset/Stability The Onset/Stability detection enhancement suite analyzes the cardiac cycle intervals to determine if a patient’s rhythm should be treated (VT) or if therapy should be inhibited (SVT).
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-11 Ventricular Redetection Ventricular Redetection occurs following any: • Ventricular therapy delivery • Diverted therapy due to reconfirmation analysis (diverted-reconfirm) • Manually diverted therapy • Therapy not available at Detection Met Redetection uses the same ventricular detection window process and programmed tachycardia rate thresholds as initial detection to identify a tachyarrhythmia.
3-12 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION • Post-shock Stability • Post-shock SRD • Post-shock Rhythm ID (uses AFib Rate Threshold, Stability, V Rate > A Rate, and SRD) With the exception of Rhythm ID, all post-shock detection enhancements perform the same as the corresponding Initial Detection enhancements (with Rhythm ID, Vector Timing and Correlation is not available post-shock).
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-13 Ventricular Detection Windows Appropriate therapy delivery is dependent upon accurately classifying a patient’s rhythm. To ensure that appropriate therapy is delivered, the pulse generator employs detection windows to differentiate tachycardias. Each ventricular zone has a detection window that consists of the 10 most recent RV R–R intervals measured by the pulse generator.
3-14 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION in a higher window would also be classified as fast in any lower windows (Figure 3-4 on page 3-14). VF Zone Rate = 200 min-1 (bpm) = 300 ms 8 of 10 intervals are fast, VF window is satisfied. VT Zone Rate = 150 min-1 (bpm) = 400 ms S = Slow F = Fast 7 of 10 intervals are fast, VF window not satisfied. 6 of 10 intervals are fast, VF window not satisfied.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION • If at any point during Duration a zone’s detection window detects fewer than 6 of 10 fast intervals, that zone’s Duration is reset to 0 (Figure 3-7 on page 3-16). Duration will start again only if the detection window becomes resatisfied. VT detection window remains satisfied during VT Duration. Right Ventricle VT detected 3-15 VT Duration 1-30 s VT window satisfied. VT Duration starts.
3-16 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION VT detection window is no longer satisfied; fewer than 6 of 10 intervals are classified as fast. Right ventricle VT detected VT Duration 1-30 seconds VT window satisfied. VT Duration starts. Need 8 of 10 intervals classified as fast to restart VT Duration. VT Duration resets to zero. VT Duration will start again when the window becomes resatisfied. Duration resets when during the Duration period the window is no longer satisfied. Figure 3-7.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION • 3-17 If the higher zone’s detection window does not remain satisfied, then the Duration timers for the lower ventricular zones are no longer ignored. Programmed therapy for lower ventricular zones will be initiated when a lower ventricular zone’s duration is met and no higher ventricular zone’s window is satisfied (Figure 3-8 on page 3-17, Figure 3-9 on page 3-17). VF window satisfied. VF Duration starts. VF window remains satisfied.
3-18 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Redetection Duration is programmable in the lower ventricular zones of a multi-zone configuration. It is nonprogrammable in the VF Zone. Post-shock Duration can be programmed in the same manner; the values programmed in the lower ventricular rate zones must be greater than or equal to the values programmed in the higher zones.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-19 Ventricular Episodes If three consecutive fast ventricular beats are detected, then the pulse generator performs the following: • Increments the episode number • Allocates memory for history data and electrogram storage • Starts monitoring for a detection window to be satisfied When any zone’s detection window becomes satisfied, the start of a ventricular episode is declared and duration timers begin in those zones where detection windows are sati
3-20 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Table 3-6.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Detection window is no longer satisfied; fewer than 6 of 10 intervals are classified as fast. 3-21 Detection window does not become satisfied. Detection window satisfied. 10 s Start Duration. Start episode. Figure 3-14. expired Duration did not expire. Duration resets to zero. Start End-of-Episode timer. End-of-Episode times out. Episode is over.
3-22 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Right Ventricle Ventricular rate remains fast. Shock Detection window does not become satisfied. Detection window satisfied. Shock 30 s Charging Start End-ofEpisode timer. Start Post-shock Detection met. Duration Start Charging. End-of-Episode timer resets to zero. Restart End-of-Episode timer. End-of-Episode times out. Episode is over. This example illustrates a Treated Episode when Ventricular mode is Monitor + Therapy.
3-23 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION If either Rhythm ID or Onset/Stability is selected, enhancement parameters are used in addition to ventricular rate and duration for therapy decisions (Table 3-7 on page 3-23) as follows: Table 3-7. • Vector Timing and Correlation inhibits therapy when the conduction vector (EGM morphology and timing) during tachyarrhythmia matches a reference conduction vector of the patient’s normal sinus rhythm.
3-24 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Table 3-7. Enhancement parameters available with detection enhancements (continued) Rhythm ID Enhancement Parameter Onset/Stability Initial Post-Shock Initial Post-Shock Onset – – – – X – – SRDg X X X X a. This enhancement is not individually programmable. b. When Rhythm ID is selected, this enhancement is automatically enabled when Atrial Tachyarrhythmia Discrimination is programmed to On.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Table 3-8.
3-26 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Table 3-9.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-27 generator calculates a Feature Correlation Coefficient and makes the following therapy decisions based on the calculation: • If at least 3 out of 10 beats are correlated, the rhythm is classified as SVT • If fewer than 3 out of 10 beats are correlated, the rhythm is classified as VT Rhythm ID makes its decision to treat or inhibit therapy at the end of Duration.
3-28 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Number of Intervals 1 Intervals in ms 620 2 600 3 580 4 580 5 620 6 600 7 640 8 560 9 600 Atrium Compute the sum of the atrial intervals. Average = 600 ms = 100 min-1 (bpm). Number of Intervals Average ventricular rate (150 min-1 [bpm]) is greater than average atrial rate (100 min-1 [bpm]) by at least 10 bpm, so delivery therapy. Compute the sum of 10 most recent ventricular intervals. Average = 400 ms = 150 min-1 (bpm).
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-29 The intrinsic atrial rate is declared to be above the AFib Rate Threshold in the following manner (Figure 3-18 on page 3-29): • Atrial analysis begins at initiation of ventricular tachyarrhythmia detection. Each atrial interval is classified as faster or slower than the AFib Rate Threshold Interval. • When 6 of the last 10 intervals are classified as faster than the AFib Rate Threshold, the device declares AF to be present.
3-30 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION When AFib Rate Threshold and Stability are used alone, ventricular therapy is initiated when a stable rhythm is declared. Ventricular therapy is initiated for an unstable rhythm when it is determined that the atrial rate is less than the AFib Rate Threshold (Table 3-10 on page 3-30).
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Table 3-10. 3-31 AFib Rate Threshold and Stability combinations and resulting therapy (continued) Detected Ventricular Rhythma Therapy Decisionb Unstable, A < AFib Rate Threshold Treat Stable, A < AFib Rate Threshold Treat a. If the detected ventricular rhythm changes, then the appropriate, corresponding row in the table is evaluated. b. Decisions to inhibit can be overridden by V > A or expiration of SRD.
3-32 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Stability to Inhibit The Stability parameter may help you identify rapid rhythms originating in the atrium, such as AF. These rhythms may result in unstable ventricular rhythms whose rate exceeds the lowest rate threshold and should not be treated. If a rhythm is declared stable when Duration expires, programmed therapy will be delivered. If the rhythm is declared unstable, ventricular therapy will be inhibited.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-33 Shock if Unstable When programmed to Shock if Unstable, the stability analysis helps determine if ventricular ATP therapy should be bypassed in preference for the first programmed ventricular shock therapy (which may be low- or high-energy) for the ventricular zone (Figure 3-20 on page 3-33).
3-34 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION When a detection window becomes satisfied, the pulse generator begins calculating for sudden Onset in a two-stage sequence. • Stage 1 measures the ventricular intervals prior to the start of the episode and locates the pair of adjacent intervals (pivot point) where the cycle length decreased the most. If the decrease in cycle length is equal to or greater than the programmed Onset value, stage 1 declares sudden Onset.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Duration = 5 seconds SRD = 30 seconds Evaluate programmed detection enhancements. If enhancements indicate to inhibit therapy, start SRD timer; otherwise, deliver therapy. 0s Detection window satisfied 0s If detection enhancements indicate therapy, deliver therapy. 5s Duration starts. Start detection enhancement analysis. Figure 3-21. Continue detection enhancement analysis throughout SRD time. 3-35 SRD times out. Deliver therapy.
3-36 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION The AFib Rate Threshold, Stability, and Vector Timing and Correlation detection enhancement combination also includes V Rate > A Rate; both AFib Rate Threshold and V Rate > A Rate are enabled when Atrial Tachyarrhythmia Discrimination is programmed to On. This combination is only available when the Rhythm ID detection enhancement suite is enabled, and only for Initial Detection (Table 3-11 on page 3-36 ).
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION 3-37 Table 3-12. Vector Timing and Correlation and Stability combinations with resulting therapy decision if Atrial Tachyarrythmia Discrimination is programmed to Off (continued) Detectiona b Dectected Ventricular Rhythma c Therapy Decision Post-shock Unstable Inhibitd Post-shock Stable Treat a. If the detected ventricular rhythm changes, then the appropriate, corresponding row in the table is evaluated. b.
3-38 TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION If V Rate > A Rate is programmed to On and is True, it will take precedence over all inhibitor enhancements. Combinations of Onset and Stability When Stability is programmed to inhibit, it may be combined with Onset to provide even greater specificity in classifying arrhythmias. This combination of detection enhancements is available only when the Onset/Stability detection enhancement suite is enabled and is available only for Initial Detection.
TACHYARRHYTHMIA DETECTION VENTRICULAR DETECTION Table 3-14. Combinations of Onset And Stability and resulting therapy (continued) Detection Rhythm Onset And Stability Combinationa b Onset Or Stability Combinationc Sudden, unstable Inhibit Treat Sudden, stable Treat Treat a. If the detected ventricular rhythm changes, then the appropriate, corresponding row in the table is evaluated. b. The And combination is the nominal setting when both are enabled. c.
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4-1 TACHYARRHYTHMIA THERAPY CHAPTER 4 This chapter contains the following topics: • "Ventricular Therapy" on page 4-2 • "Antitachycardia Pacing Therapies and Parameters" on page 4-10 • "Ventricular Shock Therapy and Parameters" on page 4-21 - DRAFT -
4-2 TACHYARRHYTHMIA THERAPY VENTRICULAR THERAPY VENTRICULAR THERAPY The pulse generator can deliver the following types of therapy to terminate VT or VF: • Antitachycardia pacing (ATP) • Cardioversion/defibrillation shocks ATP pacing schemes are bursts of pacing pulses delivered between the ventricular pace/sense electrodes. Shocks are high-voltage biphasic pulses delivered through the shocking electrodes synchronously with detected heart activity.
TACHYARRHYTHMIA THERAPY VENTRICULAR THERAPY 4-3 Ventricular Therapy Selection The pulse generator determines which ventricular therapy to deliver based on the following rules: • Each successive therapy delivery must be greater than or equal to the strength of the previous therapy in a ventricular episode. Whenever a ventricular shock therapy has been delivered, no further ventricular ATP therapy is allowed in that episode since ATP therapy is of lower strength than shock therapy.
4-4 TACHYARRHYTHMIA THERAPY VENTRICULAR THERAPY • If the arrhythmia is not converted and an arrhythmia is redetected in the same ventricular zone, the next programmed therapy in that zone is selected and delivered (Figure 4-2 on page 4-4), followed again by redetection. If the arrhythmia persists in the same zone, the therapy will progress in that zone.
TACHYARRHYTHMIA THERAPY VENTRICULAR THERAPY 4-5 NOTE: In the VT-1 zone of a 3-zone configuration or the VT zone of a 2-zone configuration, one or two ATP schemes may be programmed as the only therapy, with all shocks in the lowest zone programmed to Off. If those pacing schemes do not terminate an arrhythmia detected in the VT-1 zone, no further therapy will be delivered in the episode unless the rate is redetected in a higher zone.
4-6 TACHYARRHYTHMIA THERAPY VENTRICULAR THERAPY This is the third shock, since two programmable shocks have been delivered. Zone ATP1 ATP2 VF VT VT-1 2 QUICK CONVERT ATP Shock 1 Shock 2 On/Off 5J 11 J 6 max max max max 1.
TACHYARRHYTHMIA THERAPY VENTRICULAR THERAPY The arrhythmia accelerated back to the VF zone, the seventh shock is delivered. The arrhythmia persists in the VF zone so the eighth (and final) shock is delivered. A sixth shock is delivered since the arrhythmia is in the VF zone.
4-8 TACHYARRHYTHMIA THERAPY VENTRICULAR THERAPY Zone ATP1 ATP2 Shock 1 Shock 2 Remaining Shocks 2J 11 J max max max max max 1 VF VT QUICK CONVERT ATP On 2 VT-1 3 4 max max 5 Burst Scan N/A 3J 9J max max max Burst Ramp N/A 0.1 J 2J max max max ATP1 in the VT zone is delivered because it is considered of equal strength to QUICK CONVERT ATP therapy. Figure 4-9.
TACHYARRHYTHMIA THERAPY VENTRICULAR THERAPY 4-9 for 8 of 10 fast intervals) and the Ventricular Redetection Duration to determine if the arrhythmia has terminated.
4-10 TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS determine if the arrhythmia has been terminated.
TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS • 4-11 Ramp/Scan The ATP amplitude and pulse width are common to all schemes. They are independently programmable from the normal pacing settings. The ATP amplitude and pulse width share the same programmable value as the post-therapy pacing settings. Coupling Interval Coupling Interval Burst Cycle Length Burst Cycle Length Redetection ATP Pace Pulse Burst 1 Burst 2 ATP Scheme Figure 4-11.
4-12 TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS • The Maximum Number of Pulses parameter determines the greatest number of pulses used in an ATP burst and may be programmed independently for each ATP scheme. After the maximum number of pulses is reached in a burst, each additional burst remaining in the scheme contains the programmed Maximum Number of Pulses. The parameter is available only if the Pulse Increment is greater than zero.
TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS 4-13 Interval decreases from one burst to the next within a multiple-burst scheme (Figure 4-14 on page 4-13). NOTE: You cannot program an ATP burst that lasts longer than 15 seconds. The length of an adaptive burst is calculated based on the interval of the ventricular zone in which the ATP is programmed, which means it is based on worst-case timing.
4-14 TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS • When the Coupling Interval is programmed as adaptive, the Coupling Interval will not re-adapt following redetection when the following are programmed to On (greater than zero): – Coupling Interval Decrement––the decrement value determines the timing of the first pulse in subsequent bursts – Scan Decrement––the decrement value determines the timing of the second pulse in subsequent bursts Burst Cycle Length (BCL) The Burst
TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS 4-15 Burst Scheme A Burst scheme is a sequence of critically timed pacing pulses intended to interrupt a reentrant loop, usually delivered at a rate faster than the patient’s tachycardia. An ATP scheme is defined as a Burst (as indicated on the PRM screen) when the timing of all pacing intervals within a burst is the same. The first BCL of each Burst is determined by the programmed BCL.
4-16 TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS If subsequent bursts are required, the programmed Ramp Decrement will be applied based on the calculated BCL of that subsequent burst (Figure 4-16 on page 4-16). Burst Cycle Length = 75% Ramp Decrement (R-R Within Burst) = 10 ms Scan Decrement (R-R Between Bursts) = 0 ms C.I.
TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS Initial BCL is determined and then Scan Decrement is applied on the next burst 300 ms 300 ms 300 ms 300 ms BCL of previous Burst is determined and then Scan Decrement is applied again on the next burst 290 ms 290 ms 290 ms Redetect Scan 4-17 290 ms 280 ms 280 ms 280 ms 280 ms Redetect Scan Scan Burst Cycle Length = 300 ms Scan Decrement = 10 ms Ramp Decrement = 0 ms Coupling Interval Decrement = 0 ms Figure 4-17.
4-18 TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS Scan C.I. 300 ms C.I.
TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS 4-19 Ventricular ATP Time-out The Ventricular ATP Time-out forces the pulse generator to skip over any remaining ATP therapy in a ventricular zone to begin delivering ventricular shock therapy programmed in the same zone. This parameter is effective only for ventricular therapy delivery. The ATP Time-out may be used in the VT or VT-1 zone as long as ATP therapy is programmed to On.
4-20 TACHYARRHYTHMIA THERAPY ANTITACHYCARDIA PACING THERAPIES AND PARAMETERS The timer alone does not invoke therapy; the rate and duration criteria and detection enhancements must still be satisfied in order for a shock therapy to be delivered. If three zones are programmed, you may program ATP Time-out settings in each of the lower two ventricular zones (Figure 4-20 on page 4-20). Programmed therapy for lower zones: VT-1 ATP Time-out = 40 s VT ATP Time-out = 30 s ATP is programmed in VT-1 and VT zones.
TACHYARRHYTHMIA THERAPY VENTRICULAR SHOCK THERAPY AND PARAMETERS 4-21 In the event that QUICK CONVERT ATP was unsuccessful in converting the rhythm and shock therapy is required, the feature’s algorithm minimizes the delay to begin charging. QUICK CONVERT ATP is not applied to any rhythm above a maximum rate of 250 bpm. VENTRICULAR SHOCK THERAPY AND PARAMETERS The pulse generator delivers shocks synchronous to a sensed event. The shock vector, energy level, and polarity of the shocks are programmable.
4-22 TACHYARRHYTHMIA THERAPY VENTRICULAR SHOCK THERAPY AND PARAMETERS output is accomplished by varying pulse width to adjust to changes in lead impedance. The first two shocks in each ventricular zone can be programmed to optimize charge time, longevity, and safety margins. The remaining shock energies in each zone are nonprogrammable at the maximum-energy value. Charge Time Charge time is the time the pulse generator requires to charge for delivery of the programmed shock energy.
TACHYARRHYTHMIA THERAPY VENTRICULAR SHOCK THERAPY AND PARAMETERS 4-23 The selection of the shock polarity applies to all shocks delivered by the device. If the preceding shocks in a zone are unsuccessful, the last shock of that zone will be automatically delivered at an inverted polarity to the previous shock (initial or reversed) (Figure 4-22 on page 4-23).
4-24 TACHYARRHYTHMIA THERAPY VENTRICULAR SHOCK THERAPY AND PARAMETERS If the patient is subject to non-sustained arrhythmias, reconfirmation may be desirable in order to prevent delivery of unnecessary shocks to the patient. The device monitors tachyarrhythmias during and immediately following capacitor charging. During this time, it checks for the spontaneous conversion of the tachyarrhythmia and determines whether ventricular shock therapy should be delivered; it does not affect therapy selection.
TACHYARRHYTHMIA THERAPY VENTRICULAR SHOCK THERAPY AND PARAMETERS 4-25 2. If 5 of 10 beats are not detected as slow (or less than 4 consecutive slow beats after an unsuccessful QUICK CONVERT ATP attempt) and charging completes, post-charge reconfirmation is performed after charging ends. After the post-charge refractory and the first sensed event, the pulse generator measures up to 3 intervals following charging and compares them to the lowest rate threshold.
4-26 TACHYARRHYTHMIA THERAPY VENTRICULAR SHOCK THERAPY AND PARAMETERS - DRAFT -
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SYSTEM GUIDE TELIGEN™ 100 IMPLANTABLE CARDIOVERTER HIGH ENERGY DEFIBRILLATOR REF E102, E110 CAUTION: Federal law restricts this device to sale by or on the order of a physician trained or experienced in device implant and follow-up procedures.
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5-1 PACING THERAPIES CHAPTER 5 This chapter contains the following topics: • "Pacing Therapies" on page 5-2 • "Basic Parameters" on page 5-2 • "Post-Therapy Pacing" on page 5-9 • "Temporary Pacing" on page 5-10 • "Sensors and Trending" on page 5-11 • "Atrial Tachy Response" on page 5-19 • "Rate Enhancements" on page 5-26 • "Lead Configuration" on page 5-31 • "AV Delay" on page 5-32 • "Refractory" on page 5-36 • "Noise Response" on page 5-41 • "Ventricular Tachy Sensing Interactions"
5-2 PACING THERAPIES PACING THERAPIES PACING THERAPIES Single chamber ICDs provide ventricular bipolar (pace/sense) normal and post-therapy bradycardia pacing, including adaptive-rate modes. Dual chamber ICDs provide both atrial and ventricular bipolar (pace/sense) normal and post-therapy bradycardia pacing, including adaptive-rate modes. The bradycardia pacing function is independent of the tachycardia detection and therapy functions of the device, with the exception of interval-to-interval sensing.
PACING THERAPIES BASIC PARAMETERS 5-3 Post-Therapy Settings include the following: • Pacing parameters, which are independently programmable from normal and temporary pacing parameters • Post-ventricular shock Brady Mode Brady modes provide you with programmable options to help individualize patient therapy. This pulse generator includes the pacing modes identified in the Programmable Options appendix.
5-4 PACING THERAPIES BASIC PARAMETERS If you have any questions regarding the individualization of patient therapy, contact your sales representative or call Technical Services at the number shown on the back cover of this manual. Lower Rate Limit (LRL) LRL is the number of pulses per minute at which the pulse generator paces in the absence of sensed intrinsic activity. The following interactive limits are effective when programming the LRL.
PACING THERAPIES BASIC PARAMETERS 5-5 During PES, Manual Burst pacing, and ATP, runaway protection is temporarily suspended to allow for high-rate pacing. Maximum Tracking Rate (MTR) The MTR is the maximum rate at which the paced ventricular rate tracks 1:1 with nonrefractory sensed atrial events. MTR applies to atrial synchronous pacing modes, namely DDD(R) and VDD(R). The following are considerations for programming the MTR: • Interactive limits ("Lower Rate Limit (LRL)" on page 5-4).
5-6 PACING THERAPIES BASIC PARAMETERS Maximum Sensor Rate (MSR) MSR is the maximum pacing rate allowed as a result of sensor control from accelerometer input.
PACING THERAPIES BASIC PARAMETERS 5-7 Pacing without modified ventricular timing 150 AV 200 ms VA AV + VA MSR 400 ms (150 min-1 [ppm]) AV 150 ms (conducted event) V-A 200 ms Forced extension of the V-A interval Pacing interval = AV + VA = 350 ms Pacing with modified ventricular timing 150 AV 200 ms VA AV + VA + extension MSR 400 ms (150 min-1 [ppm]) AV 150 ms V-A Ext.
5-8 PACING THERAPIES BASIC PARAMETERS Amplitude (V) Pulse Width (ms) Figure 5-2. Pulse waveform Amplitude The pulse Amplitude, or voltage of the output pulse, is measured at the leading edge of the output pulse (Figure 5-2 on page 5-8). Amplitudes are independently programmable. The following considerations are important: • During temporary programming, the brady pacing mode may be programmed to Off. In effect, this turns Amplitude off to monitor the patient’s underlying rhythm.
PACING THERAPIES POST-THERAPY PACING 5-9 • High Sensitivity (low value)—when Sensitivity is programmed to a very sensitive setting, the pulse generator may detect signals unrelated to cardiac depolarization (oversensing, such as sensing of myopotentials) • Low Sensitivity (high value)—when Sensitivity is programmed to a less sensitive setting, the pulse generator may not detect the cardiac depolarization signal (undersensing) POST-THERAPY PACING Post-therapy pacing provides alternate pacing therapy fo
5-10 PACING THERAPIES TEMPORARY PACING Post-Therapy Period The Post-Therapy Period determines how long the pulse generator operates using the post-therapy parameter values.
PACING THERAPIES SENSORS AND TRENDING 5-11 NOTE: Emergency therapy is the only function that can be initiated until the Temporary function is stopped. 4. To stop the Temporary pacing mode, select the Stop button. The Temporary pacing mode also stops when you command emergency therapy from the PRM or when you press the DIVERT THERAPY key. Once stopped, the pacing reverts to the previously programmed Normal/Post-Therapy settings.
5-12 PACING THERAPIES SENSORS AND TRENDING • • • Recording Method—programmable: – 30-Second Average – Beat to Beat Duration––programmable: – When Recording Method is set to Off or 30-Second Average––fixed, approximately 25 hours – When Recording Method is set to Beat to Beat––fixed, approximately 40 minutes at 75 bpm Data Storage—programmable: – Continuous—contains the most recent data available.
PACING THERAPIES SENSORS AND TRENDING 5-13 NOTE: Activity involving minimal upper body motion, such as bicycling, may result in only a moderate pacing response. NOTE: Adaptive-rate pacing has been shown to be potentially proarrhythmic. Use caution when programming adaptive-rate features. Accelerometer The accelerometer detects motion that is associated with a patient’s physical activity and generates an electronic signal that is proportional to the amount of body motion.
PACING THERAPIES SENSORS AND TRENDING • Activity Threshold • Reaction Time • Response Factor • Recovery Time Activity Threshold Activity Threshold prevents rate increases due to low-intensity, extraneous motion (e.g., motion caused by respiration, heart beat, or in some cases tremor associated with Parkinson’s disease). Activity Threshold represents the activity level that must be exceeded before the sensor-driven pacing rate will increase.
PACING THERAPIES SENSORS AND TRENDING 5-15 Activity Threshold MSR Paced rate Lower threshold setting Nominal threshold setting Higher threshold setting LRL Rest Stage 1 Stage 2 Rest Time This figure demonstrates the effect of increased or decreased Activity Threshold settings in response to a theoretical two-stage exercise test. Figure 5-5.
PACING THERAPIES SENSORS AND TRENDING Reaction Slopes ort MSR Paced rate Sh min No al Lon g LRL 0 10 20 30 40 50 Seconds Figure 5-6. Reaction Time and paced rate Reaction Time MSR Shorter Reaction Time Paced rate 5-16 Nominal Reaction Time Shorter Longer Longer Reaction Time LRL Rest Stage 1 Stage 2 Rest Time Figure 5-7. Reaction Time in exercise test Programming Reaction Time for Normal Settings also changes the corresponding selection for Post-Therapy Settings.
PACING THERAPIES SENSORS AND TRENDING 5-17 Rate Response Slopes 16 MSR 14 12 m 8 6 4 2 1 l Paced rate No 10 ina LRL Low High Activity Figure 5-8. Response Factor and paced rate The pacing rate achieved can be limited either by the detected activity level or the programmed MSR. If the detected activity level results in a steady-state rate below the MSR, the pacing rate can still increase when the detected activity levels increase (Figure 5-9 on page 5-17).
PACING THERAPIES SENSORS AND TRENDING Recovery Time Recovery Time determines the time required for the paced rate to decrease from the MSR to the LRL in the absence of activity. When patient activity concludes, Recovery Time is used to prevent an abrupt decrease in pacing rate (Figure 5-10 on page 5-18 and Figure 5-11 on page 5-19).
