FAQ Pacemakers, Pacing Leads, Programmer

Help with Pacemakers, Leads, Programmer

These Frequently Asked Questions (FAQs) cover Pacemakers and Leads from Dextronix, manufactured by BIOTRONIK.  The most common and shortest questions are listed first.  Topics requiring a longer explanation (e.g., graphs and photos) may be found in the Appendix at the end of this document.

Dextronix handles all technical support for BIOTRONIK pacemaker products used in veterinary medicine.  For more information contact Dextronix Technical Support at (866) 744-3427 or techsupport@dextronix.com.  Please do NOT contact BIOTRONIK directly, they will redirect to us.

Download the complete FAQ shown below

Question:  Can I look up technical aspects of the Dextronix pacemakers, leads, and programmer on the Internet?

Answer:  Extensive support links are on the Dextronix web site at:


For further information or support call Dextronix Technical Support at (866) 744-3427.

Question:  I implanted the lead and checked the threshold, R wave, and impedance – all looked very good.  But after tunneling and reinserting the lead into the pacemaker, we have no capture, no pacing at all.  The lead has not moved as seen in fluoroscopy, and the connection inside the header looks okay.  What is wrong?

Answer:  The pacemaker has activated AUTOMATED LEAD CHECK and reverted to unipolar mode.  The quickest solution is to put the edge of the pacemaker into the pocket, you will see immediate pacing and capture on the ECG.  This is a safety feature, designed to continue pacing in case of a lead fracture.  You can easily program the pacemaker back to Bipolar mode or turn off LEAD CHECK before the implant.  If it still fails to capture after placement in the pocket, trying both unipolar and bipolar, there is another problem, please call Technical Support.  For more information on this topic Dextronix’s technical support document at the following link:


Question:  Why is there no rate response (RR) or rate increase seen in the Operating Room (O.R.) when jiggling the pacemaker or patient?


  1. Go to PARAMETERS and ensure the mode is set to VVIR. Turn off the radio frequency (RF) transmitter, if active, which will re-activate the wand (for Renamic programmers and newer pacers only).  The pacer cannot operate in rate-response mode when using RF communication.  When you re-interrogate, the RF will be restored as it is the nominal/default setting for this function.
  2. To turn OFF the RF transmitter: From the MAIN (FOLLOW UP) screen, touch PARAMETERS, then MORE (in the right column).  New tabs will appear in the top row.  The tab has two pages, so you may need to scroll to the second page using the two arrows under the small wrench icon under the ECG.  Select the correct pacemaker model that you are using (e.g., Edora or Enitra).
  3. Now, when you are at your pacemaker model, look down for TELEMETRY. Right under that are two options, RF (Radio Frequency) and PGH (Programming Head or Wand).  The option that is colored blue shows the active mode.  Tap on the one you want, and the programmer will switch back and forth, from RF to PGH (Wand).  You can confirm the RF is active by looking at the very top row, on the right.  The small green bar graph icon is the signal strength indicator for the RF.  When you switch to PGH (Wand), that icon will disappear.  The default of these settings is the RF – every time you interrogate the pacer it will come up in RF.

Question:  On the Renamic programmer, what are the icons on the top right of the programmer?

Answer:  In the top right corner, above the clock, is the familiar Bluetooth® Symbol.  That function will be activated in the future, it is presently dormant.  Just to the left of that is a radar-signal appearing symbol, with the letter “H”, indicating the Head (Wand) is active.  It should have two (2) or greater bars when communicating with the pacer.  To the left of that is a circle, empty or grayed-out.  It will be replaced by a green bar graph showing the signal strength of the RF connection.  At this point the RF is active, you may move the wand and programmer to another table or across the room.  You can also operate the built-in Pacing System Analyzer (PSA) via this RF connection, without the wand.  To turn off the RF connection and return to the wand, refer to NO RATE RESPONSE (FAQ# 3, above).

Question:  At follow-up while in standard VVIR mode with an accelerometer, the rate histogram shows very little rate response in the middle and fast ranges.  How can I get it to go faster?


  1. After printing the Histogram, Go to PARAMETERS and ensure the mode is VVIR. If not, change it to VVIR.
  2. In PARAMETERS, go to > SENSOR/RATE FADING and adjust the following one at a time and in small steps:
    • Increase MAX SENSOR rate.
    • Increase GAIN.
    • Then clear statistics by going to DIAGNOSTICS > START STATISTICS.

Question:  At follow-up in CLS mode, the rate histogram shows very little rate response in the middle and fast ranges.  How can I get it to go faster?


  1. From home/interrogation first screen, go to PARAMETERS.
  2. Under Mode (far left), be sure it’s set to VVI-CLS, NOT VVIR.
  3. Go down 2 rows to CLS, click on the word “CLS”.
  4. A new box opens, tap on CLS RESPONSE, change it to VERY LOW, then OK button.
  5. If you do not see that box, touch very small down-pointing arrow in the bottom left corner and repeat step 4. Note, that arrow toggles back AND forth between those two (2) boxes.
  6. Select VERY LOW, then CLOSE, and OK on same page.
  7. Go back to main screen (click anywhere), the “PROGRAM” tab at bottom should be blue, indicating the programmer IS READY to send new settings but has not done so yet. Click on that button, then OK, it will turn black.
  8. Finally, we want to clear out the memory, to restart the statistics. Under the PARAMETERS tab, drop down to DIAGNOSTICS, then click on large tab at bottom “START STATISTICS”. It is recommended to keep the patient for at least two (2) hours and walk him around a little bit.  Then interrogate again and go to DIAGNOSTICS.  If you do not see enough pacing, repeat step 6 above, and change the CLS Response to LOW to enable faster rates.  One of these two settings should give you a normal shaped curve, skewed to the right, that is, most of rate will be slow.  Keep in mind, you can always resort to VVIR/Accelerometer, where we can titrate the rates a bit more.

Question:  How can I turn the Pacemaker completely off?

Answer:  This varies with different Pacemaker models.  Go to PARAMETERS > MODE > ALL MODES, select OFF > PROGRAM (blue button in bottom row).  If OFF is not available, programming the pacemaker to the lowest possible amplitude and pulse width (e.g., 0.2V / 0.1ms) will prevent pacing and capture, in most cases.  Contact Dextronix if this does not solve the problem.

Question:  How can I increase the battery longevity on the shelf?

Answer:  Ensure the rate response (VVIR) is not on, it should be programmed to VVI.  Program it to the lowest outputs, as described in the FAQ answer for TURN THE PACEMAKER COMPLETELY OFF (FAQ# 6, above).  Be sure to re-program the pacemaker back to normal outputs (4.0V / 0.4ms) before implanting.

Question:  How do I increase the battery longevity when the pacemaker is implanted?

Answer:  Standard in the industry is to set the amplitude at two-times (2x) the threshold, at 0.4ms or 0.5ms.  For example, if the threshold is 0.9V at 0.4ms, you would set the Output to 1.8V.  In the case of a high threshold, increase the pulse width (not the output in Volts) to the next available setting.  Doubling the pulse width will double (2x) the energy but doubling the amplitude will quadruple (4x) the energy and deplete the battery faster.  Use of the Automatic Capture Control (ACC) where the output hovers slightly over the threshold and increases the output if loss of capture occurs, can greatly increase the longevity, see AUTOMATIC CAPTURE CONTROL (ACC) (FAQ# 9, below).

Question:  What is Automatic Capture Control (ACC)?

Answer:  Once activated, this algorithm looks to ensure capture on every single beat, while programmed slightly above threshold.  The factory setting for ACC is ON, but it only works with a pulse width of 0.4ms.  A pulse width of 0.5ms might gain more consistent capture than 0.4ms, but ACC will not work with 0.5ms.  When active, ACC searches for an evoked response (capture) right after the output pulse.  If none is seen within 100ms, the device emits an output pulse 0.5V higher than the current threshold, along with a pulse width of 1.0ms to ensure capture.

A more detailed version can be found in the following article:

When signal analysis is successful, voltage step-down occurs at every elicited beat, firstly in large (0.6V) and secondly in smaller (0.1V) steps, until an ineffective stimulus (loss of capture) is delivered.  The last effective pulse is defined as the threshold, and the programmed safety margin (default 0.5V) is added to determine the current output.  ACC works at 0.4ms pulse width only.  EVERY paced beat is checked for ER detection, and a pack-up pulse at 1.0ms is delivered in the instance of loss of capture.  In the event three (3) consecutive beats require delivery of the back-up pulse, signal analysis occurs again, and a new threshold measurement is triggered to update the current pacing output; if test start amplitude equals the current threshold, VCC reverts to a safety output as test start voltage +1.2V.

Reference: EP Europace, Vol 18, Issue 10, Oct 2016, p 1551-1560

In contrast to other companies, the BIOTRONIK algorithm works on a beat-to-beat basis, and again runs a threshold every day, at midnight.  This is shown to be 97% effective in the Ventricle – the best in the industry.

In addition to being a great safety feature, the ACC adds significant longevity to the battery, usually increasing battery life by one (1) or two (2) years.  This can be visualized on the programmer parameter page, in the lower right corner when you activate the ACC.  The longevity is calculated at 100% pacing at the programmed output.  If the patient has any intrinsic activity the pacer will inhibit, and the battery will last longer.

Question:  Can I practice changing parameters or run tests if a pacemaker is not available?

Answer:   Yes.  On both the Renamic and ICS-3000 programmers, from the MAIN screen, before you interrogate, and before the FOLLOW UP tab appears, go the very bottom row, click on the DEVICE LIST tab.  From there, select the pacemaker model you are working with.  This will allow you to enter patient data, change parameters, view diagnostics, etc.  You can also partially run threshold, sensing and impedance tests, but they will be incomplete as there is no lead attached.

Question:  While practicing programming the Pacemaker while it is still in the package, it appears some functions are not active?

Answer:  This is because the pacemaker is in “Shipment Mode” to conserve battery.  The pacemaker stays this way until the leads are inserted, then the pacemaker automatically “wakes up” fully.

Question: Are Dextronix Pacemakers compatible with other manufacturer’s leads?
Answer: Yes. All the pacemaker companies meet the VS1 (Voluntary Standard), or IS1 (International Standard),
3.2mm, which are identical nomenclature for the same connector specifications. This means the sealing rings are on the body of the lead, not inside the pacer header. One company had leads labeled “3.2mm”, but not VS1/IS1, where the rings were part of the header, and therefore not compatible with the VS1/IS1 standard. It is worth noting, but unlikely you would encounter one of those leads today. If there is a question on the lead being VS1/IS1, you should contact the manufacturer or Dextronix.
Dextronix pulse generators will automatically recognize the lead type and configuration of any modern pacing lead with IS-I  connector (all current Biotronik, Medtronic, St. Jude Medical, Boston-Scientific, and Sorin products are IS-I equipped and acceptable).

WARNING: Using leads from Pacetronix, or any other brand not listed above, in combination with Dextronix devices will void all warranties made by Dextronix and will not be supported. Proper pacemaker therapy depends on lead quality, and it is of outmost importance that the implanted lead is new, unused, and not re-sterilized (which may damage the steroid coating).

Question:  Is it okay to use another manufacturer’s torque wrench on Dextronix pacemakers (or when is a #2 torque wrench not a #2 torque wrench)?


  1. No, Dextronix recommends only using the supplied BIOTRONIK torque wrench. While wrenches are usually interchangeable between companies, BIOTRONIK wrenches have a slight variation to prevent the wrench from going too deeply into the lead port, thus blocking the lead.  It is possible to use another company’s wrench in a BIOTRONIK pacer, but not optimal.  The BIOTRONIK #2 wrench (Industry Standard) may be used in other companies’ pacers, but the converse is not true.  It is best to use BIOTRONIK wrenches with BIOTRONIK pacemakers.  For more information see the diagrams in Appendix A14.
  2. Set screw Adjustment: Back-off the set screw prior to insertion of a lead connector.  Failure to do so may result in damage to the lead and/or difficulty connecting the lead.
  3. Cross Threading Set screws: To prevent cross threading a set screw, do not bact the set screw completely out of the threaded hole.  Leave the torque wrench in the slot of the set screw while the lead is inserted.
  4. Tightening Set screws: Do not overtighten the set screws.  Use only the BIOTRONIK supplied torque wrench.
  5. Sealing System: Be sure to properly insert the torque wrench into the perforation at an angle perpendicular to the connector receptacle.  Failure to do so may result in damage to the plug and its self-sealing properties.

APPENDIX A14: BIOTRONIK Torque Wrench or (When is a #2 Wrench not a #2?)

Dextronix pacemakers are manufactured by BIOTRONIK to very tight, exacting specifications, more so than some other companies.  It was noted that inserting a BIOTRONIK lead into a BIOTRONIK lead port would compress air, tending to push the lead back out.  This was eliminated by having a hole all the way through the set screw, allowing air to escape.  But doing so allowed the torque wrench to pass all the way through the screw, down into the port, and blocking the lead.  This issue was alleviated by adding a slight “shoulder” or “bevel” to the shaft of the wrench (see Figure A14-1, below)

Question:  Does my programmer have a built-in pacing system analyzer (PSA)?

Answer:  Most of the Renamic (white) programmers, and some of the ICS-3000 (blue) programmers have a PSA incorporated inside of the Programmer.  For the ICS-3000 with the PSA, you will see an attached component labeled “ICS3000 IMPLANT MODULE” at the very bottom right corner of the programmer.  Programmers with the PSA will show “PSA Docking Station” in the bottom right corner.  For the Renamic, rotate the unit around so you are looking at the right side of the case.  At the far right, above the small ECG symbol, there is a round receptacle (for surface ECG cable), followed by 3 USB Ports.  If the area to the left of the round receptacle is smooth, there is no PSA in this programmer.  If you see a small panel 4.5 inch wide with another round receptacle and a small round spring-loaded cover, that is the PSA.  Cables for the PSA are included with the Renamic and available from Dextronix.

Question:  How do I use the built-in pacing system analyzer (PSA)?

Answer:  The PSA, whether built-in or free standing, connects as follows:

  1. The small black alligator clip goes on the proximal pin of the lead, which plugs into the pacemaker (which is the negative/cathode). This wire ultimately goes to the distal tip/helix, in the right ventricle.
  2. The red alligator clip goes on the ring electrode, which is the positive/anode.

Question:  Why doesn’t the rate increase when I wiggle the dog in the operating room (O.R.)?

Answer:  This answer is similar to NO RATE RESPONSE (RR) (FAQ# 3) with more specifics.  Dextronix/BIOTRONIK pacemakers need to have a lead inserted to be able to take an impedance measurement, and for all the functions to operate.  Until the lead is inserted, the device is still in the “Shipment Mode”, waiting to be activated.  This is to extend battery longevity while on the shelf.  So, when you plug in the lead, all functions will be activated automatically – you do not have to do anything else.

Some newer Dextronix pacemakers, in conjunction with the Renamic programmer, can communicate wirelessly (even from across the room) once it has been interrogated.  You need to interrogate with the wand like you normally do, then you can remove the wand.

Note that the sensor input is suspended while the device is in the Interrogation mode.  The normal fix for this is to remove the wand, but with the wireless communication you would have to move the wand FAR AWAY (e.g., down the hallway).  The solution is to turn OFF the wireless (radio frequency or RF) communication.  When that is done, the pacemaker will revert to standard communication through the wand.  To restore RF just replace the wand over the device, wait for the small bar graph to appear, then remove the wand, and the Rate Response will become active.

To turn off RF (temporarily or permanently), also see NO RATE RESPONSE (RR) (FAQ# 3):

  1. Touch MORE (in the right column).
  2. Touch EDORA (or ENITRA, or the appropriate model name).
  3. Tab (top row after Notifications). “RF” should be highlighted in blue (active).
  4. Select/touch PGH (Programming Head). Pacer is now communicating through the wand.
  5. Select the parameters you want, the select the blue PROGRAM button.
  6. To confirm the RF is off, notice the very top row, above ECG. To the right of EDORA (or other model name), “Serial #” is a colored bar graph.  That is the signal strength of the RF.  It should go away completely when you switch back to PGH.  Note that RF is the default setting – every new interrogation will automatically go to RF.

Question:  How do I find online information from BIOTRONIK?

Answer:  The best source for online information (NOT technical support) may be found at the following link:


Question:  How do I know the lead is screwed into tissue?

Answer:  Just because the helix is extended as viewed per fluoroscopy does not mean it is properly fixated.  The best way to verify proper fixation is to gently pull back about an inch on the lead, while observing the L shape at the junction of the superior vena cava and right atrium.  If the curve starts to disappear (i.e., “flatten out”) then it is fixated properly.  Do not pull back anymore, but gently advance the lead until the “L” shape is restored.  You are now ready to test threshold, R wave, and impedance.

Question:  What is Closed Loop Stimulation (CLS)?

Answer:  Closed-loop stimulation (CLS) is a proven sensor concept for rate adaptive pacing that measures changes in the unipolar right ventricular impedance, which correlates to changes of the right ventricular contractility known as inotropic change and reflects the autonomic nervous innervation of the heart.  It can mimic heart rate changes due to emotion, stress, and REM sleep.  A more detailed description may be found in Appendix A23 at the end of this document.

Question:  How much battery life is remaining?

Answer:  Touch Parameters, then see bottom right corner to see how many years are left.  If no programmer is available, see MAGNET RESPONSE (FAQ# 26, below)

Question:  What is the response of Dextronix pacemakers to an external magnet?

Answer:  All Dextronix pacemakers have 3 programmable options for the Magnet Response, indicated as AUTO, SYNCHRONOUS, and ASYNCHRONOUS.  The nominal/default setting from the factory is AUTO, which will pace VOO (Asynchronous) at a rate of 90 beats per minute for a strong battery, and 80 beats per minute for a pacer that has reached the Elective Replacement Time (ERT).  When ERT is reached, there is a minimum of 6 months remaining, and often more, depending on output settings and percentage pacing.  The final indicator shown on the programmer is EOS (i.e., End of Service), formerly known as EOL (i.e., End of Life).  If EOS/EOL is seen on the programmer, battery failure is imminent, urgent replacement is recommended.  (Editor’s note: when patients heard the nurse or tech tell the doctor that the pacer was at End of Life, they thought they were talking about the patient’s life and became upset. Thus, the industry changed the terminology to End of Service to lessen the patient’s anxiety.)

Question:  Does Dextronix have a VDD pacemaker and lead?

Answer:  Dextronix does not make a dedicated VDD Lead.  However, all Dextronix pacemaker models have a VDD mode available.

Question: How do I set up the Primary Password and Recovery Password on a Renamic programmer?
Answer: Use the following steps:
1. Launch and select Guest Access.
2. Touch MORE (in the right column).
3. Touch RELEASE (upper middle).
4. Keyboard pops up, type in: “erasePassWD”.
5. Press the Enter Key.
6. The system will restart and prompt you to set the Primary Password and Recovery Password.
It is the sole responsibility of the user to keep a record after changing or resetting the Recovery Password. Dextronix
is not responsible and cannot assist customer to regain access to their Renamic after the Recovery Password has
been changed.

Question: Does the threshold rise when using Medtronic or another manufacturer’s leads?
Answer: All modern endocardial pacing leads come with Dexamethasone steroid coating to reduce the inflammatory effects raising the thresholds in the first weeks after implantation. We suspect re-sterilization of pacing leads with methods other than ETO may  impair or even damage the Dexamethasone coating rendering it dysfunctional and possibly cause a rise of the threshold values over time. Re-sterilization of pacing leads and then use in combination with Dextronix or Biotronik pulse generators will void all warranties made by Dextronix.
WARNING: We highly discourage the reuse of explanted pacing leads or use of new but expired pacing leads that
have been re-sterilized. Dexamethasone coatings degrade over time and their ability to perform properly in an
implant when past their expiration date is unknown to us.
Customers mixing Dextronix/Biotronik pulse generators with Medtronic (or other manufacturer’s) pacing leads must
ensure that the Medtronic pacing lead is new, not past its expiration date, and not re-sterilized to avoid unexpected
threshold rises after implantation.