VENTAK PRIZM Series Implantable Cardioverter Defibrillator System Guide

ABOUT THIS MANUAL This ICD System Guide contains information about the VENTAK PRIZM family of ICDs, herein referred to as VENTAK PRIZM, used with the Model 2844 Software Application and the ZOOM LATITUDE Programming System, which includes the Model 3120 Programmer/Recorder/Monitor (PRM). Refer to the PRM Operator’s Manual for full instructions. The VENTAK PRIZM family includes the following devices: Dual Chamber

Single Chamber

VENTAK PRIZM 2 DR

VENTAK PRIZM 2 VR

VENTAK PRIZM DR

VENTAK PRIZM VR

VENTAK PRIZM HE DR

VENTAK PRIZM HE VR

The VENTAK PRIZM family of products include dual-chamber and single-chamber models. This manual is written for full description of dual-chamber devices. For use with single-chamber devices, ignore references to dual-chamber features, such as atrial parameters or dual-chamber modes. When a single-chamber mode is interrogated, the PRM screens will reflect only the features available for single-chamber devices. All PRM screen illustrations in this manual show typical screens for a VENTAK PRIZM 2 DR pulse generator. The screens you see when interrogating or programming other pulse generator models will be similar but may not include any dualchamber or adaptive-rate fields, depending on the model or programmed pacing mode. Throughout this manual, the following text conventions will be used: PRM KEYS Screen Text

1., 2., 3. •

The names of the PRM keys will appear in capital letters (eg, PROGRAM, INTERROGATE) When text appearing on the PRM screen is referred to in the manual, it will appear with the first letter of each word capitalized. Numbered lists indicate a series of instructions that should be followed in the order given. Bullets precede items in a list, or a series that is not sequential.

The following are trademarks of Guidant Corporation: ENDOTAK, LATITUDE, QUICK NOTES, QUICK START, TRIAD, VENTAK PRIZM, ZOOM.

Graphical Symbols for Medical Device Labeling Symbol

Definition Opening instructions.

Wand placement indicator

CONTENTS INFORMATION FOR USE... 1-1 CHAPTER 1 Device Description... 1-2 Related Manuals and Information Tools... 1-2 Indications and Usage... 1-3 Contraindications... 1-3 Warnings... 1-3 General... 1-3 Programming and Device Operation... 1-4 Implant Related... 1-4 Precautions... 1-4 Clinical Considerations... 1-4 Sterilization, Storage, and Handling... 1-4 Implantation and Device Programming... 1-5 Follow-up Testing... 1-8 Explant and Disposal... 1-8 Environmental and Medical Therapy Hazards... 1-8 Home and Occupational Environments... 1-11 Adverse Events... 1-12 Potential Adverse Events... 1-14 Clinical Studies... 1-15 Patient Selection and Treatment... 1-18 Individualization of Treatment... 1-18 Evaluating Prospective Patients... 1-19 Device Features... 1-20 Mechanical Specifications... 1-21 Factory Nominal Parameter Settings... 1-22 Maintaining Device Effectiveness... 1-22

X-Ray Identifier... 1-22 Latitude Patient Management System... 1-23 Pulse Generator Longevity... 1-23 Warranty Information... 1-24 Federal Communications Commission (FCC)... 1-24 Patient Counseling Information... 1-25 Patient Manual... 1-25 Product Reliability... 1-26 References... 1-26 USING THE PROGRAMMER/RECORDER/MONITOR... 2-1 CHAPTER 2 Starting Up the Programmer and Software... 2-2 Startup Screen... 2-2 ECG Display from the Startup Screen... 2-3 Quick Start... 2-5 Utilities Button on the Startup Screen... 2-6 Select PG Button... 2-7 Introduction to CONSULT Software Terminology and Navigation... 2-8 VENTAK PRIZM Main Application Screen... 2-8 Buttons and Icons... 2-9 Logos... 2-12 Tachy Zone Configuration... 2-12 Brady Therapy Summary... 2-13 Toolbox and Toolbox Buttons... 2-13 General Window Functions... 2-14 ECG Display on the Main Application Screen... 2-14 Utilities Button on the Main Application Screen... 2-19 Establishing Telemetry Communication... 2-27 Interrogating the Pulse Generator... 2-28 Load Initial Parameter Values... 2-29

Changing Parameter Values... 2-29 Programming the Pulse Generator... 2-31 DIVERT THERAPY... 2-32 STAT SHOCK... 2-32 STAT PACE... 2-33 TACHYARRHYTHMIA DETECTION... 3-1 CHAPTER 3 Tachy Mode Parameter... 3-2 Accessing the Tachy Mode Parameter... 3-3 Rate Sensing... 3-4 Calculating Rates and Refractory Periods... 3-4 Rate Thresholds and Zones... 3-5 Initial Detection... 3-5 Detection Windows... 3-6 Duration Parameter... 3-8 Reconfirmation/Committed Shock... 3-11 Episodes... 3-12 Detection Enhancements... 3-15 Use of Atrial Information... 3-17 V Rate > A Rate... 3-17 AFib Rate Threshold... 3-18 Onset... 3-22 Stability Analysis... 3-23 Combinations of Onset and Stability... 3-26 Sustained Rate Duration (SRD)... 3-27 Redetection... 3-28 Redetection Duration and Post-shock Duration ... 3-28 Post-shock Parameters... 3-30 Programming Zone Configurations and Detection Parameters... 3-31 TACHYARRHYTHMIA THERAPY CHAPTER 4

... 4-1

Therapy Prescription... 4-2 Therapy Selection... 4-3 Redetection After Therapy Delivery... 4-7 Antitachycardia Pacing Therapies and Parameters... 4-8 Burst Parameters... 4-9 Coupling Interval (C.I.) and Coupling Interval Decrement... 4-10 Burst Cycle Length (BCL)... 4-12 Minimum Interval... 4-13 Burst Scheme... 4-13 Ramp Scheme... 4-14 Scan Scheme... 4-14 Ramp/Scan Scheme... 4-15 ATP Pulse Width and ATP Amplitude... 4-16 ATP Time-out... 4-17 Shock Therapy and Parameters... 4-18 Shock Energy... 4-18 Waveform and Polarity... 4-21 Committed Shock/Reconfirmation of the Arrhythmia... 4-22 Accessing Therapy Parameters... 4-24 BRADYCARDIA PACING THERAPY... 5-1 CHAPTER 5 Description of Bradycardia Pacing Therapy... 5-2 Normal Brady Pacing Parameters... 5-2 Brady Mode... 5-3 Lower Rate Limit (LRL)... 5-3 Maximum Tracking Rate (MTR)... 5-3 Maximum Sensor Rate (MSR)... 5-4 Pulse Width... 5-6 Amplitude... 5-6 Dynamic Parameters... 5-7 Post-shock Bradycardia Pacing... 5-7 Post-shock Pacing Delay... 5-8 Post-shock Pacing Period... 5-9

Accessing Normal and Post-shock Brady Parameters... 5-9 Temporary Bradycardia Pacing... 5-10 SENSOR SUBMENU-... 5-12 Adaptive-Rate Pacing Parameters... 5-12 Maximum Sensor Rate (MSR)... 5-12 Activity Threshold... 5-12 Reaction Time... 5-13 Response Factor... 5-14 Recovery Time... 5-15 TACHY RESPONSE SUBMENU-... 5-17 Atrial Tachy Response (ATR)... 5-17 ATR Trigger Rate... 5-17 ATR Duration... 5-17 Entry Count... 5-18 Exit Count... 5-18 Fallback Mode... 5-19 Fallback Time... 5-19 ATR/VTR Fallback LRL... 5-19 Ventricular Tachy Response (VTR)... 5-20 Atrial Flutter Response... 5-21 PMT Termination... 5-22 RATE ENHANCEMENTS SUBMENU-... 5-23 Rate Hysteresis... 5-23 Hysteresis Offset... 5-23 Rate Hysteresis in Adaptive-Rate Modes... 5-23 Rate Hysteresis in Nonadaptive-Rate Modes... 5-24 Search Hysteresis... 5-24 Rate Smoothing... 5-24 Rate Smoothing Up... 5-26 Rate Smoothing Down... 5-26 Maximum Pacing Rate (DDI, DVI, and SSI)... 5-26 Rate Smoothing Example for Dual-chamber Tracking Mode... 5-27 AV DELAY SUBMENU-... 5-29

AV Delay... 5-29 AV Delay (fixed interval)... 5-29 Dynamic AV Delay... 5-29 Sensed AV Offset... 5-30 Sensed AV Offset to Fixed AV Delay... 5-31 Sensed AV Offset to Dynamic AV Delay... 5-31 AV Search Hysteresis... 5-32 AV Search Interval... 5-32 AV Increase... 5-33 REFRACTORY SUBMENU-... 5-34 Ventricular Refractory Period–VRP... 5-34 VRP (fixed interval)... 5-34 Dynamic VRP... 5-34 Atrial Refractory-PVARP... 5-35 PVARP After PVC... 5-36 V-Blank After A-Pace... 5-37 A-Blank After V-Pace... 5-37 A-Blank After V-Sense... 5-37 NOISE RESPONSE SUBMENU-... 5-40 Noise Response... 5-40 SYSTEM DIAGNOSTICS... 6-1 CHAPTER 6 System Summary... 6-2 Quick Check... 6-3 Diagnostic Evaluation... 6-6 Battery Status... 6-6 Intrinsic Amplitude Test... 6-9 Lead Impedance Test... 6-11 Pace Threshold Test... 6-13 Daily Measurement (VENTAK PRIZM 2 only)... 6-16

PATIENT DIAGNOSTICS... 7-1 CHAPTER 7 Therapy History... 7-2 Therapy History Screens... 7-3 Conversion Summary... 7-3 Arrhythmia Logbook... 7-5 Patient Triggered Monitor (VENTAK PRIZM 2)... 7-18 Trending Data

... 7-20

Snapshot Viewer... 7-23 ELECTROPHYSIOLOGIC TESTING... 8-1 CHAPTER 8 EP Test Features... 8-2 Atrial Stimulation and Backup VVI Pacing During EP Testing... 8-3 EP Test Screen... 8-4 Induction Methods... 8-7 V Fib Induction... 8-7 Shock on T Induction... 8-8 Programmed Electrical Stimulation (PES)... 8-10 Manual Burst Pacing... 8-12 External Induction... 8-13 Slaved Induction... 8-14 Commanded Therapy Methods... 8-15 Commanded Shock... 8-15 Commanded ATP... 8-16 PRE-IMPLANT AND IMPLANT INFORMATION... 9-1 CHAPTER 9 Items Included in Device Packaging... 9-2 Factory Nominal Parameter Settings... 9-2

Implanting the Pulse Generator... 9-3 Recommended Sequence using device-based testing (DBT):... 9-3 Step A: Check Equipment... 9-3 Step B: Interrogate and Check the Pulse Generator... 9-4 Step C: Implant the Lead System... 9-4 Step D: Take Baseline Measurements... 9-5 Step E: Form the Implantation Pocket... 9-6 Step F: Connect the Leads to the Pulse Generator... 9-7 Step G: Evaluate Lead Signals... 9-11 Step H: Program the Pulse Generator... 9-11 Step I: Implant the Pulse Generator... 9-12 Step J: Complete and Return the Implantation Form to Guidant... 9-14 POST-IMPLANT INFORMATION... 10-1 CHAPTER 10 Follow-up Testing... 10-2 Sensitivity Adjustment... 10-4 Explantation... 10-4 Magnet/Beeper Setup... 10-6 Magnet Operation... 10-7 Determine the Tachy Mode of the Pulse Generator... 10-8 Change the Tachy Mode... 10-8 Inhibit Tachyarrhythmia Therapy and Induction... 10-9 GLOSSARY... 11-1 CHAPTER 11 PROGRAMMABLE OPTIONS... A-1 APPENDIX A PACEMAKER INTERACTION... B-1 APPENDIX B EXTERNAL CABLE CONNECTIONS... C-1 APPENDIX C Surface ECG Connections... C-2 Troubleshooting... C-6

Optimizing the Quality of ECG Tracings... C-6 REFERENCES... D-1 APPENDIX D ICD/LEAD COMPATIBILITY... E-1 APPENDIX E MADIT II EXPANDED INDICATION... F-1 APPENDIX F Adverse Events... F-1 Observed Adverse Events... F-1 Mortality... F-4 Summary of MADIT II Clinical Study... F-5 MADIT II Summary of Clinical Study... F-5 Study Design... F-6 Subgroup Analysis of MADIT II Patient Population... F-19

INFORMATION FOR USE

INFORMATION FOR USE CHAPTER 1 This chapter contains the following topics: •

“Device Description” on page 1-2

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“Indications and Usage” on page 1-3

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“Warnings” on page 1-3

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“Precautions” on page 1-4

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“Adverse Events” on page 1-12

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“Clinical Studies” on page 1-15

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“Device Features” on page 1-20

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“Mechanical Specifications” on page 1-21

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“Maintaining Device Effectiveness” on page 1-22

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“X-Ray Identifier” on page 1-22

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“Latitude Patient Management System” on page 1-23

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“Pulse Generator Longevity” on page 1-23

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“Federal Communications Commission (FCC)” on page 1-24

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“Patient Counseling Information” on page 1-25

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“Product Reliability” on page 1-26

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“References” on page 1-26

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INFORMATION FOR USE DEVICE DESCRIPTION

DEVICE DESCRIPTION The Guidant VENTAK PRIZM ICD automatic, implantable cardioverter defibrillators are designed to detect and terminate ventricular tachycardia (VT) and ventricular fibrillation (VF) and provide bradycardia therapy (atrial and ventricular pacing). Therapies include both low- and high-energy shocks using either a biphasic or monophasic waveform. The VENTAK PRIZM models use the Guidant TRIAD electrode system for defibrillation energy delivery. By using the metallic housing of the pulse generator as an active electrode, combined with the Guidant ENDOTAK two-electrode defibrillation lead, energy is sent via a dual-current pathway from the distal shocking electrode to the proximal electrode and to the pulse generator case. VENTAK PRIZM devices also offer a wide variety of antitachycardia pacing schemes to terminate slower, more stable ventricular tachyarrhythmias. Bradycardia pacing, including adaptive-rate features, is available to detect and treat bradyarrhythmias and to support the cardiac rhythm after defibrillation therapy. The devices denoted with DR offer dual-chamber bradycardia features (atrial and/or ventricular pacing and sensing), and the devices denoted with VR offer singlechamber bradycardia features (ventricular pacing and sensing). The pulse generator, along with compatible commercially available pace/sense leads and cardioversion/defibrillation leads constitutes the implantable portion of the ICD system. The device’s small, physiologic shape minimizes pocket size and may minimize device migration. The lead systems for the VENTAK PRIZM ICD pulse generators are implanted using either transvenous or transthoracic techniques. The ZOOM LATITUDE Programming System, which includes the Model 3120 Programmer/Recorder/Monitor (PRM), the Model 2844 Software Application, and an accessory telemetry wand constitutes the external portion of the ICD system. The external components allow interrogation and programming of the pulse generators, as well as access to the devices' diagnostic features. VENTAK PRIZM systems can be programmed to provide a variety of detection options. They also can provide noninvasive diagnostic testing and therapy history data.

Related Manuals and Information Tools The Operator's Manual for the Guidant Programmer/Recorder/Monitor provides information specific to the programmer, such as setting up the system, maintenance, and handling. Physician's manuals for the leads provide specific information and instructions regarding the implanted leads. The Physician’s Technical Manual is packaged with the pulse generator and provides the information

INFORMATION FOR USE INDICATIONS AND USAGE

1-3

needed to implant the device at nominal parameter settings. All information in the Physician’s Technical Manual is also included in this manual.

INDICATIONS AND USAGE Guidant ICDs are intended to provide ventricular antitachycardia pacing and ventricular defibrillation for automated treatment of life threatening ventricular arrhythmias.

CONTRAINDICATIONS Use of the VENTAK PRIZM pulse generators are contraindicated in: •

Patients whose ventricular tachyarrhythmias may have reversible cause, such as 1) digitalis intoxication, 2) electrolyte imbalance, 3) hypoxia, or 4) sepsis, or whose ventricular tachyarrhythmias have a transient cause, such as 1) acute myocardial infarction, 2) electrocution, or 3) drowning

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Patients who have a unipolar pacemaker

WARNINGS General •

Labeling knowledge. Read this manual thoroughly before implanting the pulse generator to avoid damage to the ICD system. Such damage can result in injury to or death of the patient.

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Do not kink leads. Kinking leads may cause additional stress on the leads, possibly resulting in lead fracture.

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Avoid shock during handling. Program the pulse generator Tachy Mode(s) to Off during implant, explant, or post-mortem procedures to avoid inadvertent high voltage shocks.

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Backup defibrillation protection. Always have sterile external and internal defibrillation protection available during implant. If not terminated in a timely fashion, an induced tachyarrhythmia can result in the patient's death.

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INFORMATION FOR USE PRECAUTIONS

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Resuscitation availability. Ensure that an external defibrillator and medical personnel skilled in cardiopulmonary resuscitation (CPR) are present during post-implant device testing should the patient require external rescue.

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Magnetic resonance imaging (MRI). Do not expose a patient to MRI device scanning. Strong magnetic fields may damage the device and cause injury to the patient.

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Diathermy. Do not subject a patient with an implanted pulse generator to diathermy since diathermy may cause fibrillation, burning of the myocardium, and irreversible damage to the pulse generator.

Programming and Device Operation •

Atrial tracking modes. Do not use atrial tracking modes in patients with chronic refractory atrial tachyarrhythmias. Tracking of atrial arrhythmias could result in VT or VF. (Applies to dual-chamber devices only.)

Implant Related •

Separate pulse generator. Do not use this pulse generator with another CRM 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). Retrograde conduction combined with a short PVARP might induce PMT.

Sterilization, Storage, and Handling •

For single use only-do not resterilize devices. Do not resterilize the device or the accessories packaged with it because the effectiveness of resterilization cannot be ensured.

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If package is damaged. The pulse generator blister trays and contents are sterilized with ethylene oxide gas before final packaging. When the pulse generator is received, it is sterile, provided the container is intact. If the packaging is wet, punctured, opened, or otherwise damaged, return the device to Guidant.

INFORMATION FOR USE PRECAUTIONS

1-5

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Storage temperature and equilibration. Recommended storage temperatures are 0°–50°C (32°–122°F). Allow the device to reach a proper temperature before programming or implanting the device because temperature extremes may affect initial device function.

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Device storage. Store the pulse generator in a clean area, away from magnets, kits containing magnets, and sources of electromagnetic interference (EMI) to avoid device damage.

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Use before date. Implant the device system before the USE BEFORE date on the package label because this date reflects a validated shelf life. For example, if the date is January 1, do not implant on or after January 1.

Implantation and Device Programming •

Expected benefits. Determine whether the expected device benefits outweigh the possibility of early device replacement for patients whose tachyarrhythmias require frequent shocks.

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Lead system. Do not use any lead with this device without first verifying connector compatibility. Using incompatible leads can damage the connector or result in potential adverse consequences, such as undersensing of cardiac activity or failure to deliver necessary therapy.

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Telemetry wand. Make sure the telemetry wand is connected to the PRM system and that it is available throughout the session. Verify that the wand cord is within reach of the pulse generator.

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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.

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Device communication. Use only the designated PRM and software application to communicate with the pulse generator.

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STAT PACE settings. When a pulse generator is programmed to STAT PACE settings, it will continue to pace at the high-energy STAT PACE values if it is not reprogrammed. The use of STAT PACE parameters will decrease device longevity.

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Pacing and sensing margins. Consider lead maturation in your choice of pacing amplitude, pacing pulse width, and sensitivity settings.

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INFORMATION FOR USE PRECAUTIONS

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An acute pacing threshold greater than 1.5 V or a chronic pacing threshold greater than 3 V can result in loss of capture because thresholds may increase over time.

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An R-wave amplitude less than 5 mV or a P-wave amplitude less than 2 mV can result in undersensing because the sensed amplitude may decrease after implantation.

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Pacing lead impedance should be within the range of 200 Ω and 2000 Ω.

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Line-powered equipment. Exercise extreme caution if testing leads using linepowered equipment because leakage current exceeding 10 mA can induce ventricular fibrillation. Ensure that any line-powered equipment is within specifications.

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Proper programming of the lead configuration. If the Lead Configuration is programmed to Bipolar when a unipolar lead is implanted, pacing will not occur.

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Defibrillation power surge. Defibrillation that causes a power surge exceeding 360 watt-seconds can damage the pulse generator system.

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Ventricular refractory periods (VRPs) in adaptive-rate pacing. Adaptive rate pacing is not limited by refractory periods. A long refractory period programmed in combination with a high MSR can result in asynchronous pacing during refractory periods since the combination can cause a very small sensing window or none at all. Use dynamic AV Delay or dynamic PVARP to optimize sensing windows. If you are entering a fixed AV delay, consider the sensing outcomes.

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Do not bend the lead near the lead–header interface. Improper insertion can cause insulation damage near the terminal end that could result in lead failure.

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Shock waveform polarity. Never change the shock waveform polarity by physically switching the lead anodes and cathodes in the pulse generator header-use the programmable Polarity feature. Device damage or nonconversion of the arrhythmia post-operatively may result if polarity is switched physically.

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Absence of a lead. The absence of a lead or plug in a lead port may affect device performance. If a lead is not used, be sure to properly insert a plug in the unused port.

INFORMATION FOR USE PRECAUTIONS

1-7

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Electrode connections. Do not insert a lead into the pulse generator connector without first visually verifying that the setscrew is sufficiently retracted to allow insertion. Fully insert each lead into its lead port and then tighten the setscrews onto the electrodes.

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Tachy Mode to Off. To prevent inappropriate shocks, ensure that the pulse generator’s Tachy Mode(s) is programmed to Off when not in use and before handling it. For tachyarrhythmia therapy, verify that the Tachy Mode(s) is programmed to On.

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Atrial oversensing. 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. (Applies to dual-chamber devices only.)

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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. If a shocking lead impedance is less than 20 Ω, reposition the shocking electrodes to allow a greater distance between the shocking electrodes.

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ATR Entry Count. Exercise care when programming the Entry Count to low values in conjunction with a short ATR duration. This combination allows mode switching with very few fast atrial beats. For example, if the Entry Count was programmed to 2 and the ATR Duration to 0, ATR mode switching could occur on 2 fast atrial intervals. In these instances, a short series of premature atrial events could cause the device to mode switch.

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ATR Exit Count. Exercise care when programming the Exit Count to low values. For example, if the Exit Count was programmed to 2, a few cycles of atrial undersensing could cause termination of mode switching.

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Shunting energy. Do not allow any object that is electrically conductive to come into contact with the lead or device during tachyarrhythmia induction because it may shunt energy. This could result in less energy getting to the patient and damage to the implanted system.

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Replacement device. Implanting a replacement device in a subcutaneous pocket that previously housed a larger device may result in pocket air entrapment, migration, erosion, or insufficient grounding between the device and tissue. Irrigating the pocket with sterile saline solution decreases the possibility of pocket air entrapment and insufficient grounding. Suturing the device in place reduces the possibility of migration and erosion.

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INFORMATION FOR USE PRECAUTIONS

Follow-up Testing •

Conversion testing. Successful VF or VT conversion during arrhythmia conversion testing is no assurance that conversion will occur post-operatively. Be aware that changes in the patient's condition, drug regimen, and other factors may change the defibrillation threshold (DFT), which may result in nonconversion of the arrhythmia post-operatively.

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Pacing threshold testing. If the patient’s condition or drug regimen has changed or device parameters have been reprogrammed, consider performing a pacing threshold test to confirm adequate margins for pace capture.

Explant and Disposal •

Incineration. Be sure the pulse generator is removed before cremation. Cremation and incineration temperatures might cause the pulse generator to explode.

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Device handling. Before explanting, cleaning, or shipping the device, complete the following actions to prevent unwanted shocks, overwriting of important therapy history data, and audible tones.:

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Program the pulse generator Tachy and Brady Modes to Off

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Program the Magnet Response feature to Off

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Program the Beep When ERI Is Reached feature to Off

Explanted devices. Return all explanted pulse generators and leads to Guidant. Examination of explanted pulse generators can provide information for continued improvement in device reliability and will permit calculation of any warranty replacement credit due. Do not implant an explanted pulse generator in another patient as sterility, functionality, and reliability cannot be ensured.

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. Examples of EMI sources are: •

electrical power sources, arc welding equipment and robotic jacks

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electrical smelting furnaces

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large RF transmitters such as RADAR