EPMedSystems: Basic Troubleshooting Guide
No stimulation output to the patient
Check the cable between the stimulator sites and the amplifier; make sure they are not reversed.
Make sure the EP-4 site output switches are both in the ON position.
Check the stimulation settings at the bottom of the stimulation window to ensure they are set correctly.
Make sure both the current and stimulation duration settings are above pacing threshold.
No stimulation channel on screen
The markers for sites A and B on the back of the stimulator must be connected via a T-connector and a BNC cable to the PMI junction box input marked “PACE DETECT”.
Make sure the setup has PMI- for the negative pin and the correct channel selected for the positive pin. Make sure the analysis is set to STIM. To make it look square, filter between high pass DC and low pass 500Hz.
Intermittent stimulation channel
Verify the pulse width of the stimulator is at least 2 msecs in duration.
The markers for sites A and B on the back of the stimulator must be connected via BNC cable to the PMI junction box, usually on the first channel.
Make sure the setup has PMI- for the negative pin and the correct channel selected for the positive pin. Make sure the analysis is set to STIM. To make it look square, filter between DC and 500Hz..
Triggered sweep does not occur
A stimulation channel must be inserted on one of the screens to enable the triggered sweep to function. The stim must be set up on one of the catheter map pages as above.
Use the Trigger button to turn on the triggered sweep and position the trigger point by dragging the triangle with the left mouse button. You can also use the Auto REC button set to Stim to do the same thing.
Triggered sweep occurs too frequently
Edit the Stim detection parameters inside the Auto REC button. Set the Stim Detection Limit to 1000ms.
Make sure the stimulation channel is set to the right parameters and the analysis is Stim.
Cannot get my touchscreen to work with the EP-4 even though it is turned on
Turn the EP-4 stimulator off and back on. This should allow the touchscreen and computer to re-initialize with the stimulator.
To make sure this does not happen every time, do not turn the stimulator on until WorkMate is at the main menu.
Stimulator will not turn on
Verify if the stimulator power on green light is flashing. If it is flashing it indicates the serial communication cable between the EP-4 rear panel and Serial A on the main computer has dislodged or is defective. If there is no green light, replace or recharge the EP-4 battery.
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No pressure measurements
The pressure amplifier or interface cable (if applicable) must be connected via pressure transducer adapter cable to the amplifier, usually on channels 5-8.
Make sure the setup has PMI- for the negative pin and the correct channel selected for the positive pin. Make sure the analysis is set to PRES. To make it look cleaner, filter between DC and 50Hz.
The high pass should be set to DC.
Turn intervals ON by selecting the Intervals button.
Pressure measurements are too rapid
Select analysis in the catheter map Setup screen. With the cursor on PRES, select the EDIT button. Change the Update field to a larger value, such as 1500ms.
The real-time monitor display interface card may be defective. Please call technical support.
Real-time and review monitor contain patterns of dots or solid vertical lines
Adjust the GRID (#) X and Y space values in the monitor window control bars. Set the X value to 0 to turn them off.
Monitor has shadows or waves
Move the cables away from power sources or other cables.
The video splitter may be defective. Remove it and see if the problem remains.
The video cables from the main computer to the monitors may be defective.
Press de-gauss button on the monitor.
Make sure that there are no magnets or strong magnetic fields near the monitors.
Monitor has large purple line
Video cable is defective, use one with ferrites and proper shielding.
Make sure that there are no magnets or strong magnetic fields near the monitors or monitor cables.
Review monitor scrolling is not smooth
In the background Setup screen (or config screen in Windows) adjust the SCROLL PIXEL SHIFT field to change the way the system scrolls. There are two basic ways to scroll, slow and smooth or fast and block-like.
To make the scrolling slow and smooth, change SCROLL PIXEL SHIFT=2(or higher). Experiment with scrolling in the review window at different values to see what works best for you.
To make the scrolling faster, change SCROLL PIXEL SHIFT=64(or higher).
Verify that the monitor(s) is turned on.
Verify that the video cable(s) is connected to the correct video port in the back of the computer.
The video card on the Pentium computer may have dislodged. Please take the cover off and make sure all boards are seated correctly.
The video drivers are not configured correctly. Verify the configuration is correct as described below.
Dark monitor or signals
Adjust the brightness and contrast of each monitor. Turn the contrast all the way up and the brightness up without brightening the background color.
Use brighter colors for the signals.
Increasing the background Setup parameters or config screen in Windows:
REAL-TIME TRACE SIZE
Signals are noisy or contain severe noise artifact
The ground reference pin on the catheter junction box is either not attached to a viable catheter pin, or the ground reference adapter (small black cable) is broken. Change the catheter pin you are referenced to or plug a catheter pin directly into the reference.
The notch filter is not setup correctly. In the background Setup screen (From the review monitor Setup and Config.)make sure the notch filter is set to 50 or 60. Make sure the notch filter intensity is set to 0, 1 or 2 where 0 is best.
Make sure the right leg surface lead is attached to the patient securely. This is the primary intracardiac ground reference. (Skin prep with alcohol, abrasives, etc.)
Make sure catheters are connected to the pin box correctly. Use the Setup screen to verify pin position.
Check to make sure that catheter extensions are not broken and are plugged in securely. Change the catheter extension cables if necessary. If all else fails change the catheter itself.
There could be a problem with other equipment attached to the patient. Unplug different equipment in the room that may be causing the problem.
Plug the power cords of any equipment attached to the patient into the same wall outlet. This will help remove 50/60 cycle interference.
For 12 lead ECG noise, verify the electrodes are firmly connected to the patient.
The amplitude gain may be too high. Reduce the software gain. Rarely should you need to exceed +/-0.3mV/channel.
The high pass filter is too low. Too much baseline information is being passed. For intracardiac signals 30Hz is usually used as the high pass.
The high pass filter is too high. Only high frequency signals are being passed.
Check to make sure that there are no electrical cords laying on or wrapped around the amplifier and the isolation transformer is at least 6 inches away from the amplifier.
Check to make sure the surface ECG cable and/ or intracardiac cables are not intertwined with electrical cords. There could be a power cable located near the junction box interface cables, or near the stimulator site A or B cables.
Too much stimulation artifact
Make sure the stimulation suppression is turned ON.
Make sure the stimulation cables are not in close proximity to the surface ECG cable.
Make sure the catheter ground reference is not being paced or is not in close proximity to a paced catheter pin.
Make sure the right leg and right arm surface ECG lead is attached to the patient securely.
Only flat line real-time signals, or message stating “AMPLIFIER FAILURE”, or message stating “NO VALID SIGNALS ARE PRESENT”
The amplifier must be turned on.
Check for communication between the amplifier and main computer using the Communication Test from the Help button menu in Windows or from the main menu in DOS to see if the amplifier is functioning.
The wrong amplifier communication driver is installed. Was the system just upgraded or a backup restored? See the User’s Manual, chapter 11, for more details on configuring the main computer to match the amplifier.
The ethernet cable (BNC) must be attached between the ethernet card of the amplifier and the main computer. Check that the BNC cable running from the amplifier to the computer must be terminated by 50 Ohm terminators at each end. Most cards are terminated internally and would have a sticker stating this. If there is no termination sticker, each 10-BASE T board must have a BNC ‘T’ adapter and a 50 Ohm terminator attached.
Turn the amplifier off and then on. The amplifier beeps as it boots up in progressively higher tones spaced seconds apart. If it is beeping and the boards are seated then this amplifier is probably OK. See Users Manual, chapter 11 for more details about the exact sequence of beeps.
The Amplifier card(s) may be dislodged. Please take the cover off and make sure all boards are seated correctly.
Turn the system off and then on.
Small gray dots or lines appear on review or real-time monitor
In the realtime monitor window controls, select the GRID(#) button and set each value to 0. In the cathmap setup screen, set the clip value of each channel to Off.
Signals appear for catheters that are not plugged in
If you have no catheter plugged into 2 junction box pins and display the bipolar channel of those pins, you will get a slightly noisy signal, usually a flat line or wavy line. If a valid signal is put into the reference pin, the signal displayed for channels with no catheters can look like that reference pin signal except much noisier. If there are any other catheters plugged into surrounding channels, it can show parts of them as well. This is because the channels with nothing plugged into them are measuring voltages across infinite impedance. When you plug a catheter in, the impedance becomes 30-300 Ohms and it only shows the signals for the correct catheter and not other catheters. If you move your hand over the junction box, catheters that are plugged in will not display any induced signal where channels with no catheters will follow the motion of your hand. Thus during infinite impedance the channels are very good antennas for all noise and voltages in the proximity. In the background setup screen you can turn on the SHOW LEAD FAIL attribute to show which channels are connected and which are not.
Signals appear to be the same on two different channels
The stimulator creates a high impedance bridge between two catheter pins. If the stimulator is set up the pace catheter pins 1 and 2, the signal from one can be picked up on pin 2 if pin two is removed because there is a direct path through the stimulator at high impedance. This is in place to passively remove polarization from the pacing electrode.
There is a short in the catheter connector, catheter, amplifier, amplifier cables or junction box.
Stored signals are unwanted
Use the Delete button in database to delete the signals stored in the current study.
Channel labels are missing
The labels cannot always be drawn due to the large amount of signal data that needs to be drawn in a limited amount of time.
Intervals are detected too frequently
Select analysis in the catheter map Setup screen. With the cursor on the analysis type, select the EDIT button. Adjust the Thd. Floor, Thd. Level or Blanking to higher values to increase the accuracy. Adjust the filters to change the location the tick mark is placed. Set the Window to 10. Intervals are not detected Select analysis in the catheter map Setup screen. With the cursor on the analysis type, select the EDIT button. Adjust the Thd. Floor, Thd. Level or Blanking to lower values to increase the accuracy. Adjust the filters to wider bandwidth to allow more information to analyze. Set the Window to 10.
During ablation, digital data is not drawn on RF window A nine pin serial extension cable must be connected from COM2 (Serial 2 or Serial B) on the main computer to the serial port on the back of the ablation generator. The DEVICE field on the RF window must be selected to the correct value. RF catheter proximal is noisy during ablation The RF ablation generator may switch off the catheter pins during ablation. Check the generator information. Make sure the catheter ground reference is not being ablated or paced or is not in close proximity to an ablated catheter pin. RF noise is excessive The RF generator must be plugged into the EP-WorkMate isolation transformer. The ground pad must not be in close proximity to the surface ECG leads. The RF catheter cannot be used as the reference signal input into the junction box.
Contact technical support.
Measurements are not displayed in the measurement menu Click on the EDIT button and check off the ones you want to add to the menu. Use the Type selection in the measurement window to select the measurement subset most appropriate to the type of study you are doing.
Too many measurements are displayed in the measurement menu Click on the EDIT button and check off the ones you want to delete.
Each catheter map has an independent measurement menu per protocol.
Channel setup suddenly changes Changing protocols can have this effect. Remember, each protocol can be programmed to have a different channel setup. Go to Setup and choose the study or protocol that you would like. When a channel is changed, every channel that shares the same name in the current study type will change as well. This is to help you when changing filters, amplitudes and pin assignments during the study by making the same change to all channels with the same name. To keep it from doing this, assign a different and unique name to the channel you do not want changed.
System will not copy to disk Check to make sure the disk is formatted by EPMedSystems. EPMedSystems does not approve of the end-user formatting optical disks on the EP-Workmate as there is a likely potential for data loss or for formatting the hard drive and disabling the system. Optical disk information seems corrupt Use the utility scandisk to analyze the disk contents and directory. Call technical support for help in recovering optical disk data for EPMedSystems formatted disks.