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CP6-Pacemaker-Follow-up-2012 (1)

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COREPACE
MODULE #6
PACEMAKER
FOLLOW-UP
Disclosures
This presentation is provided for general educational
purposes only and should not be considered the exclusive
source for this type of information. At all times, it is the
professional responsibility of the practitioner to exercise
independent clinical judgment in a particular situation.
The device functionality and programming described in this
module are based on Medtronic products and can be
referenced in the device manuals.
Updated: August 2012
Objectives
• Identify key features of 2090 programmer.
• Provide a technique for you to complete a successful device
follow-up, company independent
• Locate threshold, sensing and impedance data on a Quick
Look™ screen
• Identify diagnostics available to aid in the management of a
device patient
• Describe the information available from the arrhythmia
episode log that aids in the analysis of a patient’s rhythm
and the device’s response
Pacing System: Programmer
On/Off
Replace Paper
Programmer Basics
Emergency
Buttons
When maximum
outputs are required,
press Emergency
Programmer Basics
Head
Touch Pen
Programmer Basics
Printer Buttons
What’s in it for you?
• What do you need to feel comfortable with a
pacemaker follow-up?
“PBL STOP”
P
B
L
Presenting Rhythm and Rate
S
T
O
P
Sensing
Battery Status
Lead Status
Threshold
Observation, Data, and Events
Program & Print
“P”
PRESENTING RHYTHM AND RATE
Evaluating Patient’s Presenting Rhythm
• What is the presenting rhythm?
• What is the patient’s indication?
– Does it correlate with the presenting rhythm?
• What is the rhythm?
– Normal sinus rhythm, Atrial fibrillation, Paced?
• What is the rate?
– Is the intrinsic rate fast, slow or normal?
• Is the sensor or the Lower Rate limit in control?
• Are we pacing or sensing?
– What is the percentage of atrial pacing?
– What is the percentage of ventricular pacing?
• Has anything changed since last follow-up session?
Paced Rhythm Recognition
Single Chamber Device: Ventricular Pacing
Single Chamber Device: Atrial Pacing (AAI)
Rhythm Recognition
Atrial Fibrillation: No Pacing
VVI / 60
Atrial Flutter: No Pacing
DDDR / 60
Rate Recognition
Programming: DDD / 60 / 120
Why do we only see pacing?
What is the patient’s intrinsic rate?
DDD Pacing
• If you know that a patient is programmed to a tracking
mode of DDD, it may give you an idea of what the patients
indication and underline rhythm is.
• DDD mode has 4 different faces of pacing.
Paced Rhythm Recognition
Sensing in the Atrium & Sensing in the Ventricle (AS-VS)
Pacing in the Atrium & Sensing in the Ventricle (AP-VS)
Paced Rhythm Recognition
Sensing in the Atrium & Pacing in the Ventricle (AS-VP)
Pacing in the Atrium & Ventricle (AP-VP)
Troubleshooting
VVI / 60
Loss of Capture
Why?
Troubleshooting
Loss of Atrial Sensing
“B”
BATTERY STATUS
Battery Status
• Determine battery voltage status
• Calculated and displayed longevity (min and max)
• Measured in volts; battery impedance used to
determine replacement time.
• RRT – Recommended Replacement Time
• ERI – Elective Replacement Indicator
• If RRT/ERI is approaching, the battery voltage
may help determine when to schedule next
patient visit.
Assessing Battery Status
Assessing Battery Status
Determining Battery Status
Without Programmer
• Apply a magnet over a Medtronic pacemaker to determine
battery status (not function)
– Asynchronous rate of 85bpm (705ms), either DOO or VOO
 Normal battery status
– Asynchronous rate of 65bpm (923ms), VOO or sometimes DOO
 Elective replacement/Recommended replacement time
• Note that the pacemaker is not programmable to a rate of 65
• When magnet is removed, pacemaker goes back to
normally programmed mode, or if at ERI/RRT, to VVI
65bpm
Knowledge Checkpoint
What is the beginning of life magnet rate and mode of a
Medtronic Pacemaker?
a.
b.
c.
d.
Depends on the device
Programmed Upper Rate and Mode
Programmed Lower Rate and Mode
85 bpm; Asynchronous Pacing (DOO, VOO)
Knowledge Checkpoint
What is the end of life magnet rate of a Medtronic
Pacemaker?
a.
b.
c.
d.
65 bpm
No pacing
Programmed Lower Rate
Depends on the device
“L”
LEAD IMPEDANCE (ohms)
Resistance and current flow
• Resistance affects current flow. Use a the garden hose as an analogy.
• There’s normal resistance when the garden hose is intact.
“Normal” resistance
• Leads with an insulation breach, will measure a low resistance reading with a resultant high
current flow, and possible premature battery depletion.
“Low” resistance
High
current
flow
• If there is a high resistance, such as a lead conductor break, the current flow will be low
or non-existent.
“High” resistance
Low current flow
Lead Insulation Break
– Insulation around the lead wire prevents current loss from the lead wire.
– Electrical current seeks the path of least resistance.
– An insulation break that exposes wire to
body fluids, which have low resistance,
causes:
• Lead impedance to fall
• Current to drain into the body
• Battery depletion
• Impedance values below 300W.
– Insulation breaks are often marked by a
trend of falling impedance values.
Decreased
resistance
< 300 W
– An impedance reading that changes
suddenly or one that is >30% is considered
significant and should be watched closely.1
1
Hayes, David L., et. al. (2000). Cardiac pacing and defibrillation: a clinical approach .
New York: Blackwell Publishing. (pg. 398).
Lead Wire Fracture
– A wire fracture within the insulating sheath may cause impedance values to rise.
– Impedance values across any break in the wire will increase and may exceed
2,000 W.
– Often such increases will be quite gradual,
representing a continuing increase in lead
degradation.
• Look for a trend in an increase in
impedance values rather than a single
lead impedance value.
– Current flow may become too low to be
effective in generating capture of the heart
– If a complete fracture of the wire occurs:
• No current will flow
• Impedance number will be “infinite”
Increased resistance
> 2000 W
Checking Lead Impedances
• Medtronic pacemakers takes a lead impedance measurement
– At 2:00am daily
– During interrogation
– Can be initiated manually
• A single lead impedance reading is not enough!
– Trends are the best indicators of the significance of those single
readings—a 30% variation is regarded as a “deviation” worth
investigation (though it may prove inconclusive)1
– Note that trends may be stable, but lead still may not be functioning
correctly
• Use lead measurements as another piece of the puzzle when
troubleshooting
• Checking with Technical Services will sometimes help confirm the
“normalcy” of out-of-range readings
1
Hayes, David L., et. al. (2000). Cardiac pacing and defibrillation: a clinical approach .
New York: Blackwell Publishing. (pg. 398).
Lead Impedance Trends
Recent Single Measurement
Lead Impedance Trends (Detail)
Click the chevron button to get more detailed
impedance information.
Knowledge Checkpoint
What is the expected range of lead impedances?
a.
b.
c.
d.
500 – 5000 ohms
200 – 2000 ohms
100 – 4000 ohms
Depends on the pacemaker
Knowledge Checkpoint
Why is knowing the lead impedance is important?
Check all that apply.
 It provides detail on longevity.
 It may warn you of a lead insulation failure or a lead conductor
fracture.
 At implant, it may indicate a loose set screw.
 It is not as important as battery status.
Knowledge Checkpoint
What are the lead impedances in this example.
“S”
SENSING (millivolts mV)
Normal Sensing Values in Sinus Rhythm
• Acute Phase (within 3 months of implant)
– P-waves = > 1.5mV
– R-waves = > 6mV
• Chronic Phase (>3 months post-implant)
– P-waves = > 1.0mV
– R-waves = > 5mV
• Note that pathologic rhythms, such as AF, will cause low
amplitude P-waves.1
1
Ellenbogen, Kenneth A. and Mark A. Wood. (2005). Cardiac Pacing and ICDs. Massachusetts: Blackwell
Publishing. (pg. 342).
Sensitivity: Not Sensitive Enough
As You Lower The Number,
You Make The Pacemaker More Sensitive
Amplitude (mV)
5 mV
5.0
2 mV
2.5
1.25
Time
1mV
(Can’t see well!)
Sensitivity: Too Sensitive
5 mV
(Sees too much!)
2 mV
Amplitude (mV)
1mV
5.0
2.5
1.25
Time
Sensitivity: Just Right
5 mV
2 mV
Amplitude (mV)
1mV
5.0
2.5
1.25
Time
Why is sensing so
important?
Oversensing vs. Undersensing
Intrinsic beat
not sensed
Scheduled pace
delivered
Undersensing leads to overpacing (symptoms?)!
Marker Channel™
shows intrinsic
activity...
...though no
activity is present
Oversensing leads to underpacing (and possible asystole)!
Knowledge Checkpoint
You are presented with the ECG strip with the
programmed device parameters below. What area of
the strip looks abnormal, A, B, C, or D?
B.
A.
Device is programmed as follows:
DDD 60–130 bpm
PAV: 150 ms
SAV: 120 ms
PVARP: 310 ms
C.
D.
Knowledge Checkpoint
Hypothesis
What explains this atrial pace?
– Intermittent atrial undersensing. The P-wave was not “seen” and
the lower rate (LRL) timed out, resulting in an atrial pace
Why did this atrial pace NOT capture?
– Atrial pacing occurred in the absolute refractory period of the atrial muscle
tissue
Knowledge Checkpoint
Confirming Your Hypothesis
What would you do?
• Interrogate and observe
the rhythm
What would you expect to
see?
• P-waves without markers
Knowledge Checkpoint
Testing Your Hypothesis
What would you do to test your hypothesis?
• Perform a sensing test
– Is the device programmed correctly?
– P/R- wave amplitudes can change
• Check lead impedances
– Undersensing can be a symptom of a lead fracture or lead
insulation failure
– Undersensing can be a symptom of lead dislodgement
Knowledge Checkpoint
Considerations
• Suppose device was programmed with an Atrial Sensitivity
of 4.0 mV
• P-waves measure 4.0- 5.0 mV
Would programming a sensing value of 2.0 mV make it
more or less sensitive?
• 2.0 mV is more sensitive than 4.0 mV
How would you program the sensitivity if you wanted to
sense fine AF, for example?
• Program sensitivity to a more sensitive value (~2.0 mV) to
make sure device can sense AF.
Knowledge Checkpoint
What area on the strip looks abnormal, A, B, C,
or D?
C.
A.
B.
Device is programmed as follows:
DDD 60–130 bpm
PAV: 150 ms
SAV: 120 ms
PVARP: 320 ms
D.
Knowledge Checkpoint
Hypothesis
What is your hypotheses?
– Atrial undersensing
– Ventricular oversensing
Knowledge Checkpoint
Hypothesis: Atrial Undersensing
X
• If this P-wave is not sensed, and not tracked, then determine when
the next atrial event should occur in the timing sequence.
• DDD 60 (1000 ms) minus the SAV (120 ms) = 880 ms from the last
QRS to the next atrial pace (the V-A interval). We should see an
atrial pace at the X.
• Thus, this cannot be atrial undersensing
Knowledge Checkpoint
Hypothesis: Ventricular Oversensing
• Remember the information
– A-A = 1000 ms
– A-V = 120 ms
– PVARP 320 ms
– Calculated the V-A = 880 ms
A
P
A
R
V
S
• Measure V-A interval backward from the atrial pace, and assume the
pacemaker senses a ventricular “event” here (VS).
• The VS starts a 400 ms refractory period in the atrium (PVC Response).
• The atrial event then falls in the PVARP of this “event” – and cannot be
used for timing, and thus it does not start an SAV.
Knowledge Checkpoint
Confirming the Hypothesis: Ventricular Oversensing
What would you do?
Interrogate and observe the rhythm
What would you expect
to see?
VS/VR markers without QRS complexes
Knowledge Checkpoint
Confirming the Hypothesis: Ventricular Oversensing
• Suppose you interrogate and see this on the strip:
– Run a sensing test
– Try to provoke oversensing
• Arm/shoulder movement
• Have patient reach across his/her body
– Program to non-RR mode
Observe Marker Channel for VS
without a QRS
Knowledge Checkpoint
Review Questions
What patient complains, what might you suspect with this strip?
• C/O syncope,
presyncope, vertigo,
weakness
What pacemaker telemetry data might indicate the cause?
• Ventricular lead impedance
What long-term effect will this condition have on device diagnostics?
• Ventricular rate diagnostics will be inaccurate because
oversensing may be recorded and interpreted as an arrhythmia
Considerations
• When there is evidence of “overpacing,” or pacing despite
intrinsic activity, consider undersensing
• When there is evidence of “under-pacing,” or pauses
without pacing, consider oversensing
** Please note, these rules are NOT absolute
“T”
THRESHOLD
Conduction System: Pacing
During pacing, the impulse travels via
the myocardium, not the native cardiac
conduction system, therefore, the QRS
is wide.
Normal QRS
Paced QRS
Is there capture of the heart?
2 Settings Used to Ensure Capture
1. Pulse amplitude – the amount of voltage delivered to the
heart by the pacemaker to ensure capture of the heart
(strength of an output pulse)
2. Pulse width – time (duration) of the pacing pulse
GOAL  Find the minimum amount of energy needed to
consistently capture the heart (stimulation threshold).
Automatic Threshold Measurements
Conducting a Threshold Test
Threshold Test Type
Change between Amplitude and Pulse
Width and which chamber to pace.
Amplitude Threshold Testing
• Keeping pulse width stable, decrement voltage
until loss of capture
Pulse Width Setting: 0.5ms (fixed)
1.5V
1.0V
.5V
Loss of capture: 0.5V @ 0.5ms
Threshold value: 1.0V @ 0.5ms
Pulse Width Threshold Testing
• Keeping voltage stable, decrement in pulse width
Voltage setting: 2.0 Volts (fixed)
.30ms
.20ms
.1ms
Loss of capture: 2.0V @ 0.1ms
Threshold value: 2.0V @ 0.2ms
.06ms
Test Results via Programmer
Final Adjusted
Threshold
Final Output Programming
• Primary goal: Ensure patient safety & appropriate device performance
Recommended safety margin:
– Acute phase (< 3 months post implant): 3 times the amplitude of the
threshold value
• Example: Threshold 1V @ 0.4ms  Final Programming: 3V @ 0.4ms
– Chronic phase (approx > 3 months post implant): 2 times the amplitude of
the threshold value
• Example: Threshold 1V @ 0.4ms  Final Programming: 2V @ 0.4ms
• Secondary goal: Extend the service life of the battery
– Amplitude values greater than the cell capacity of the pacemaker battery (usually
about 2.8 V) require a voltage multiplier, resulting in markedly decreased battery
longevity
– Typically program amplitude to < 2.5 V, while ALWAYS maintaining adequate
safety margins
• Example: A common output value might be 2.0 V at 0.4 ms
*Note: Particular care should be given to
safety margins for pacemaker dependent patient
Knowledge Checkpoint
Define pacing threshold.
Pacing Thresholds
• What is the pacing output safety margin on a chronic
system?
– Multiply the amplitude threshold by two
• What is the maximum you would want to program
the amplitude, assuming a threshold of < 1.0 V?
– Normally, try to keep the output amplitude at < 2.5 V
– Patient safety is paramount
“O”
OBSERVATIONS, DATA, & EVENTS
What else should be checked?
• What have we checked already?
– Presenting Rhythm
– Battery Status and Lead impedances
– Sensing and Threshold testing
• Other questions to consider:
– Is Rate Response programmed appropriately?
• Can the patient achieve rates to support activities of daily living?
– Is the patient having any arrhythmias?
• What kind of arrhythmias, what rates, what triggers?
– Can we program the device to extend its longevity?
• Can we encourage intrinsic events?
• The device’s diagnostic and observation recordings can help answer
some of these questions
Quick Look™ II Arrhythmia Observations
Many pacemaker patients will
develop atrial tachyarrhythmias
over the life of their device.
Observations alert the clinician
to situations that may require
further investigation.
Printed Reports-Initial Interrogation
Page 1: Device/lead status, histograms,
episode summary
Page 2: Episode logs, V rate during AT/AF
histogram, and Cardiac Compass® trend
Initial Interrogation Report
Device Status
Automatically
generated
upon interrogation.
This report
page contains
most of the
device and lead
status documentation
needed for
routine follow-up.
Initial Interrogation Report
Clinical Status
Assess rate response, percent pacing and sensing, and
occurrences of A or V high rate episodes.
Initial Interrogation Report
Arrhythmia Status
Management of atrial
tachyarrhythmias may be simplified
through use of the Cardiac
Compass® trends and arrhythmia
summary diagnostics.
Combined with the QuickLook™ II
“Observations,” this information may
help with assessment of:
• Rate-control therapy
• Rhythm-control therapy
• Risk for stroke
Optimizing Pacemakers for Patients
• Always evaluate for the presence of arrhythmia
– What type?
– Is the patient symptomatic?
Cardiac Compass is a simple way to stay
informed of trends in the patient’s atrial
arrhythmia burden, to monitoring effectiveness
of new drugs, or possible concern with anticoagulants.
Cardiac Compass also provides
trends on the ventricular
response to these arrhythmia.
Arrhythmia Management
Rate-Control Assessment*
V Rate During AT/AF Details
• Available on-screen or in initial
interrogation report
• Histogram displays percent of V-beats
paced or sensed that fall into each rate bin
• Only V-beats during mode switch included
Printed Report Version
Clinical Questions/Concerns
• Do ventricular rates recorded during
atrial tachyarrhythmias suggest that
medications need to be modified to
control ventricular response?
• Is modification of the AV node an
alternative option?
On-Screen Display
• Is conducted AF response ON?
If not, would it be useful to try?
Arrhythmia Management
Rhythm-Control Assessment
Cardiac Compass Details
• Lists AT/AF observations (if any)
• Vertical lines reflect cumulative daily
burden levels (hrs/day)
• Includes MS episodes
(or, if MS = OFF, AHR episodes)
regardless of duration
Printed Report Version
On-Screen Display
Clinical Questions/Concerns?
• Are previously undiagnosed
episodes present?
• Do episode date/times correlate to
patient symptoms?
• Has rhythm-control therapy
increased the amount of time
spent in sinus rhythm?
• Are pharmacologic or other therapy
adjustments needed?
• Are atrial tachyarrhythmias affecting
HF status or frequency of VT/VF?
Arrhythmia Management
Risk for Stroke Assessment*
Clinical Questions/Concerns
• Is there an increased risk
for stroke due to episodes
of long duration?
• Do daily burden levels suggest
that the patient may be at a
higher risk for stroke?
• Does patient have other
contributing risk factors?
• Should anticoagulation therapy
be modified or initiated?
* The information collected may help with assessment of rate-control, rhythmcontrol, and risk for stroke in patients with atrial tachyarrhythmias.
Diagnostics, Monitoring, and Trending
Summary
• Device status, clinical status, and arrhythmia status
can all be assessed through Medtronic’s pacemaker
monitoring and trending capabilities
• Comprehensive monitoring and diagnostic information
may help to confirm correct operation of device
features and assess therapy efficacies
Optimizing Pacemakers for Patients
• Always evaluate the percent pacing
– Many devices have a percent pacing counter, or look to the
histograms for this information
– Device longevity is affected by pacing outputs
• High outputs decrease longevity
• Low outputs (below about 2.0 V) don’t have as dramatic of an affect
– So reducing the percentage of unnecessary pacing will
improve device longevity and there may be other benefits to
patients (more later)
Optimizing Pacemakers for Patients
• Always evaluate the
rate histograms
– Look for a “staircase” distribution of
rates
– Ask about the
patient’s ability to
achieve their
desired levels of
activity
Rates below the LRL
may occur because of a
timing anomaly.
Rates above the
UTR/USR may indicate
an arrhythmia.
Episode Specific Diagnostics
In pacemakers, stored EGMs can be useful:
– Confirming accuracy of other arrhythmia diagnostics
• For example – is oversensing triggering arrhythmia collection?
– Collecting arrhythmia triggers
• An EGM is an ECG recorded via the pacemaker’s leads
and stored in the device
Stored EGM of an episode of AF
Reducing the Pacing Percentage
Managing AV delays
• Use auto AV extension algorithms (e.g., Medtronic’s
Search AV+) with Auto-PVARP options to:
– Reduce unnecessary right ventricular pacing
– Allow higher UTR
– Guard against retrograde conduction
Reducing the Pacing Percentage
Search AV+ example:
– AV intervals are scanned
– If the majority end in pacing (8/16) the AV delay is automatically
increased
Note: AV scanning algorithms will typically still result in
ventricular pacing about 40-50% of the time.
“P”
PROGRAMMING &
PRINTING FINAL REPORTS
Programmed Parameters
• Prior to printing have we made all the appropriate
changes?
• Are there any features that could be utilized to promote
intrinsic conduction?
• Do we need to make any changes based on testing?
• What feature is available to clinicians to get initial
parameters?
Parameter Screen Review
Print Reports
• Print Final Reports
– Sensing test results
– Threshold test results
– Key observations
– Any changes this session noted on final report
“PBL STOP”
P
B
L
Presenting Rhythm and Rate
S
T
O
P
Sensing
Battery Status
Lead Status
Threshold
Observation, Data, and Events
Program & Print
Device Follow-Up: “PBL STOP”
GOALS:
– PBL - to obtain device status before checking anything else,
including diagnostics, since some of the collected data may be
incorrect if the device / lead has an issue.
– STOP is to complete testing, make your assessments, program,
and print final reports.
– PBL STOP allows you to create a device follow-up routine and
focus on the important information in a repeatable order.
Case Study #1
One of the Nurse Practitioners in the pacemaker
clinic has asked you to take a look at the
interrogation report for one of their patients.
• 28 year old male with intermittent complete
heart block
• 10 yr old single chamber pacemaker
• Patient has been experiencing episodes of
light headedness and was seen by his
primary care physician with no findings.
• As episodes continued over a week, he
experienced near syncope several times and
called the pacemaker clinic to be seen.
• You are given the interrogation report. Utilize
the “PBL STOP” methodology to assess the
situation
Case Study #1: Interrogation Report
Case Study #1 (cont’d)
“P” – Presenting Rhythm
– Unfortunately, there is no EKG strip of the current rhythm
at interrogation.
“B” – Battery Status
– What is the battery longevity?
“L” – Lead Impedances
– Is the lead impedance in the normal range?
Case Study #1 (cont’d)
“S” – Sensing Test
– You are unable to find a sensing test print-out in the chart
“T” – Threshold Test
– You do find a recorded threshold strip
What do you see?
What is going on with this patient?
Can you name two possible solutions?
Case Study #1 (cont’d)
undersensing
oversensing
escape
escape
escape
LOC
escape
V escape interval=820ms/73 bpm
• There is intermittent oversensing, and failure to capture
with normal lead impedance.
• Sense markers do not match any cardiac activity on the
surface ECG. This could be an intermittent lead issue or
a connection issue in the header.
Case Study #1 (cont’d)
Possible Causes
• Header connection would be a possible source of problems
• Occurs when IS-1 pin is not fully inserted into header when set screw
is tightened. Set screw barely engages the distal edge of the IS-1 pin.
With time, pin may move out of the header.
• Typically see the impedance trending higher over time (in this case it
is normal).
• Higher probability if device was a recent implant.
• Incomplete Fracture
• Leads to intermittent contact between the broken ends of the lead
wire or conductor, or an insulation break that allows intermittent
shorting of the two conductors.
• High impedance would indicate a fracture, and low impedance would
indicate an insulation break.
Case Study #1 (cont’d)
What are some options for next steps?
• Urgent/emergent revision with new lead implant
• Program pacing and/or sensing of the lead to unipolar
• In event of a cardiac emergency, use transcutaneous pacing function with
Lifepak to provide backup pacing until a new lead can be placed.
What are the considerations to programming lead to Unipolar?
• Bipolar pacing is unreliable in this case, suggesting one of the conductors or
the insulation is compromised.
• Programming the polarity to unipolar simply turns off the lead’s ring electrode
and the insulation between the tip and ring conductors.
• If the tip conductor is the one with the intermittent fracture, the patient still has
the same limitations on his pacing system. If the ring conductor or insulation
is the issue, unipolar pacing resolves the safety issue of noncapture.
• Reliability of unipolar pacing would need to be established and may only be a
temporary fix.
Case Study #1 (cont’d)
Lead Monitor
• Feature that automatically detects and counts the number of changes in
impedance values.
• Device produces an observation on the Quick Look screen when impedance
is abnormal.
• May be programmed to switch polarity from bipolar to unipolar if there is
such a change and provide continued pacing.
Case Study #2
This patient has had a DDDR pacemaker for 6 years
–
–
–
–
Functioning normally
On a routine telephone check, the following strip is transmitted
The patient’s magnet is in place
What conclusions can you draw?
Asynchronous pacing
A-A
interval
705ms
V-V
interval
705ms
Normal magnet behavior, operating in DOO mode at 85 ppm
Case Study #3
•
•
•
•
Patient implanted about 6 months ago for SND
He comes to clinic for first 3 month pacemaker follow-up.
Testing will need to be conducted
How is the device currently programmed?
Case Study #3
Results of pacemaker testing:
– Battery voltage: 2.78 V
– Sensing:
• P-waves 2.0-2.5 mV
• R-waves >22.8 mV
• Underlying rhythm Sinus Brady at 50 bpm
– Thresholds
• Atrial 1.0 V tested at 0.4 ms
• Ventricular 0.8 V tested at 0.4 ms
Case Study #3
• What programming changes (if any) would you
recommend?
– Re-programming the A and V outputs to 2.0 V at 0.4 ms is
reasonable. The leads should be stable at 6 months post implant.
• Would you run any other tests or investigate any
further?
– The underlying rhythm indicates intact conduction. Consider
programming a Search AV algorithm to reduce unnecessary
ventricular pacing.
– Check the rate histograms and question the patient for the
adequacy of his rate response.
– Check other diagnostics for the presence of arrhythmia.
Case Study #4
• This elderly patient had a DDDR implanted for sinus node
dysfunction 8 weeks ago
– Discovered sinus node disease with pauses on routine physical
– Past medical history includes hypertension
• She denies palpitations
• Treatment: Hydrochlorothiazide (blood pressure medication)
– Patient comes to the clinic for her first routine check
• Patient follow-up check: Presenting rhythm, Battery Status, Lead
Impedance Measurements, Sensing and Threshold test
 All values within normal and expected limits
 Atrial and Ventricular outputs reduced to a 2.5x safety margin
• What Step is next?
– Review Observations, Data and Events
Case Study #4
Cardiac Compass Report
Is patient having AF? If so, how much?
Episodes totaling 8 hours on one day, about 4 hours on two days, and several
shorter episodes 1 min to 1 hour durations thereafter. It is noteworthy that she
has not had any more AF in 1.5 months.
Case Study #4
Cardiac Compass Report
Is the ventricular
response to AF well
controlled?
Yes, as a very low percent of the ventricular response to AF is > 100 bpm.
A Couple of Questions
• In patients with paroxysmal AF (PAF), how likely are
they to experience symptoms of AF?
Asymptomatic PAF occurs 12.1 times as often as symptomatic PAF in
symptomatic patients [Page et al, Circulation 89(1):224-7, 1994]
Asymptomatic PAF occurs in 22-27% of patients with clinical
improvement
[Wolk et al, Int J Cardiol 54:207-211, 1996]
• What is the risk of stroke or CVA to someone with
untreated AF?
5% per year for nonvalvular AF. The take-away: AF is silent and
dangerous.
[Baker, Daryll M. (2008). Stroke Prevention in Clinical Practice. London: Springer-Verlag. (pg. 27).]
Case Study #4
• Based on the Cardiac Compass® data, the MD decides to
add Sotalol 160 bid and Coumadin
• The patient returns 6 months later
– Is her arrhythmia status improved?
Yes, it has improved. Her last episode was at the end of May.
A Couple More Questions
• For this patient, how would you make the diagnosis of
PAF without these kinds of diagnostics?
– Evaluate the patient for symptoms
– Check for AF during clinic visits, routine EKGs
– Holter monitor
• For this patient, how would you evaluate the effectiveness
of your treatment without these kind of diagnostics?
– Continue routine EKGs and monitor for increase/decrease in
reported symptoms.
Key Learning Points
• PBL STOP is a methodical way to perform a device followup. Following a routine each time you interrogate a device
will increase your efficiency and thoroughness.
• The Quick Look™ screen provides and overview of key
parameters including percent pacing, impedance, sensing,
and thresholds.
• Device diagnostics aid in patient management and allow
you to maximize patient follow-up
Brief Statement: IPGs and ICDs
Indications
• Implantable Pulse Generators (IPGs) are indicated for rate adaptive pacing in patients who
may benefit from increased pacing rates concurrent with increases in activity and increases in
activity and/or minute ventilation. Pacemakers are also indicated for dual chamber and atrial
tracking modes in patients who may benefit from maintenance of AV synchrony. Dual chamber
modes are specifically indicated for treatment of conduction disorders that require restoration of
both rate and AV synchrony, which include various degrees of AV block to maintain the atrial
contribution to cardiac output and VVI intolerance (e.g. pacemaker syndrome) in the presence of
persistent sinus rhythm.
• Implantable cardioverter defibrillators (ICDs) are indicated for ventricular antitachycardia
pacing and ventricular defibrillation for automated treatment of life-threatening ventricular
arrhythmias.
• Cardiac Resynchronization Therapy (CRT) ICDs are indicated for ventricular antitachycardia
pacing and ventricular defibrillation for automated treatment of life-threatening ventricular
arrhythmias and for the reduction of the symptoms of moderate to severe heart failure (NYHA
Functional Class III or IV) in those patients who remain symptomatic despite stable, optimal
medical therapy and have a left ventricular ejection fraction less than or equal to 35% and a
prolonged QRS duration.
• CRT IPGs are indicated for the reduction of the symptoms of moderate to severe heart failure
(NYHA Functional Class III or IV) in those patients who remain symptomatic despite stable,
optimal medical therapy, and have a left ventricular ejection fraction less than or equal to 35%
and a prolonged QRS duration.
Brief Statement: IPGs and ICDs
Contraindications
• IPGs and CRT IPGs are contraindicated for dual chamber atrial pacing in patients with chronic
refractory atrial tachyarrhythmias; asynchronous pacing in the presence (or likelihood) of
competitive paced and intrinsic rhythms; unipolar pacing for patients with an implanted
cardioverter defibrillator because it may cause unwanted delivery or inhibition of ICD therapy;
and certain IPGs are contraindicated for use with epicardial leads and with abdominal
implantation.
• ICDs and CRT ICDs are contraindicated in patients whose ventricular tachyarrhythmias may
have transient or reversible causes, patients with incessant VT or VF, and for patients who have
a unipolar pacemaker.
Warnings/Precautions
• Changes in a patient’s disease and/or medications may alter the efficacy of the device’s
programmed parameters. Patients should avoid sources of magnetic and electromagnetic
radiation to avoid possible underdetection, inappropriate sensing and/or therapy delivery, tissue
damage, induction of an arrhythmia, device electrical reset or device damage. Do not place
transthoracic defibrillation paddles directly over the device. Additionally, for CRT ICDs and CRT
IPGs, certain programming and device operations may not provide cardiac resynchronization.
Also for CRT IPGs, Elective Replacement Indicator (ERI) results in the device switching to VVI
pacing at 65 ppm. In this mode, patients may experience loss of cardiac resynchronization
therapy and / or loss of AV synchrony. For this reason, the device should be replaced prior to
ERI being set.
Brief Statement: IPGs and ICDs
Potential Complications
• Potential complications include, but are not limited to, rejection phenomena, erosion through the
skin, muscle or nerve stimulation, oversensing, failure to detect and/or terminate arrhythmia
episodes, and surgical complications such as hematoma, infection, inflammation, and
thrombosis. An additional complication for ICDs and CRT ICDs is the acceleration of ventricular
tachycardia.
See the device manual for detailed information regarding the implant
procedure, indications, contraindications, warnings, precautions, and
potential complications/adverse events. For further information, please call
Medtronic at 1-800-328-2518 and/or consult Medtronic’s website at
www.medtronic.com.
Caution: Federal law (USA) restricts these devices to sale
by or on the order of a physician.
Brief Statement: Leads
Indications
• Medtronic leads are used as part of a cardiac rhythm disease management system. Leads are
intended for pacing and sensing and/or defibrillation. Defibrillation leads have application for
patients for whom implantable cardioverter defibrillation is indicated. The Attain Leads have
application as part of a Medtronic biventricular pacing system.
Contraindications
Medtronic leads are contraindicated for the following:
• Ventricular use in patients with tricuspid valvular disease or a tricuspid mechanical heart valve.
• Patients for whom a single dose of 1.0 mg of dexamethasone sodium phosphate or
dexamethasone acetate may be contraindicated. (includes all leads which contain these
steroids).
• Epicardial leads should not be used on patients with a heavily infarcted or fibrotic myocardium.
The SelectSecure Model 3830 Lead is also contraindicated for the following:
• Patients for whom a single dose of 40.µg of beclomethasone dipropionate may be
contraindicated.
• Patients with obstructed or inadequate vasculature for intravenous catheterization.
The Attain leads are contraindicated for patients with coronary venous vasculature that is
inadequate for lead placement, as indicated by venogram. For the Model 4193 and 4194 leads,
do not use steroid eluting leads in patients for whom a single dose of 1.0 mg dexamethasone
sodium phosphate may be contraindicated
Brief Statement: Leads
Warnings/Precautions
• People with metal implants such as pacemakers, implantable cardioverter defibrillators (ICDs),
and accompanying leads should not receive diathermy treatment. The interaction between the
implant and diathermy can cause tissue damage, fibrillation, or damage to the device
components, which could result in serious injury, loss of therapy, or the need to reprogram or
replace the device.
• For the SelectSecure Model 3830 lead, total patient exposure to beclomethasone 17,21dipropionate should be considered when implanting multiple leads. No drug interactions with
inhaled beclomethasone 17,21-dipropionate have been described. Drug interactions of
beclomethasone 17,21-dipropionate with the Model 3830 lead have not been studied.
• Attain leads, stylets, and guidewires should be handled with great care at all times. When using
a Model 4193 or 4194 lead, only use compatible stylets (stylets with downsized knobs and are 3
cm shorter than the lead length). Output pulses, especially from unipolar leads, may adversely
affect device sensing capabilities. Back-up pacing should be readily available during implant.
Use of leads may cause heart block. For the Model 4193 and 4194 leads, it has not been
determined if the warnings, precautions, or complications usually associated with injectable
dexamethasone sodium phosphate apply to the use of this highly localized, controlled-release
device. For a list of potential adverse effects, refer to the Physician’s Desk Reference. Patients
should avoid diathermy. Previously implanted pulse generators, implantable cardioverterdefibrillators, and leads should generally be explanted.
Brief Statement: 2090 Programmer
Intended Use
The Medtronic CareLink programmer system is comprised of prescription devices indicated for use in
the interrogation and programming of implantable medical devices. Prior to use, refer to the
Programmer Reference Guide as well as the appropriate programmer software and implantable
device technical manuals for more information related to specific implantable device models.
Programming should be attempted only by appropriately trained personnel after careful study of the
technical manual for the implantable device and after careful determination of appropriate parameter
values based on the patient's condition and pacing system used. The Medtronic CareLink
programmer must be used only for programming implantable devices manufactured by Medtronic or
Vitatron.
See the device manual for detailed information regarding the instructions for use, indications,
contraindications, warnings, precautions, and potential adverse events. For further information,
please call Medtronic at 1-800-328-2518 and/or consult Medtronic’s website at www.medtronic.com.
Caution: Federal law (USA) restricts this device to sale by or on the order of a physician.
Brief Statement: Leads
Potential Complications
• Potential complications related to the use of leads include, but are not limited to the following
patient- related conditions: cardiac dissection, cardiac perforation, cardiac tamponade, coronary
sinus dissection, death, endocarditis, erosion through the skin, extracardiac muscle or nerve
stimulation, fibrillation or other arrhythmias, heart block, heart wall or vein wall rupture,
hemoatoma/seroma, infection, myocardial irritability, myopotential sensing, pericardial effusion,
epicardial or pericardial rub, pneumothorax, rejection phenomena, threshold elevation,
thrombosis, thrombotic or air embolism, and valve damage. Other potential complications
related to the lead may include lead dislodgement, lead conductor fracture, insulation failure,
threshold elevation or exit block.
• See the specific device manual for detailed information regarding the implant procedure,
indications, contraindications, warnings, precautions, and potential complications/adverse
events. For further information, please call Medtronic at 1-800-328-2518 and/or consult
Medtronic’s website at www.medtronic.com.
• Caution: Federal law (USA) restricts these devices to sale by or on the order of a physician.
World Headquarters Contact Information
World Headquarters
Medtronic, Inc.
710 Medtronic Parkway
Minneapolis, MN 55432-5604
USA
Tel: (763) 514-4000
Fax: (763) 514-4879
www.medtronic.com
Medtronic USA, Inc.
Toll-free: 1(800) 328-2518
(24-hour technical support for
physicians and medical
professionals)
©Medtronic, Inc. 2012
Minneapolis, MN
http://www.medtronic.com
All Rights Reserved
April 2012
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