Pacemaker complication: Difference between revisions
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==Indications== | ==Indications== | ||
*Sinus Node Dysfunction-sinus bradycardia/arrest, sinoatrial block, chronotropic incompetence, a-fib. | |||
*Acquired AV block- 3rd degree block and 2nd degree type II | |||
*Chronic Bifascicular or Trifascicular block | |||
*After Acute MI-high mortality with persistent AV block post MI | |||
*Cardiac Resynchronization Therapy- Conduction delay (>150msec w/ mortality benefit) in chronic systolic heart failure further decreases EF, increases remodeling and increased MR. | |||
*Neurocardiogenic Syncope and Carotid Sinus Syndrome | |||
==Expected ECG Patterns== | ==Expected ECG Patterns== | ||
*Absence of pacer artifact indicates intrinsic depolarization | |||
*Pacing artifacts preceding depolarizations indicate successful pacing and capture | |||
*Leads in RV apex produce LBBB pattern with appropriate discordance | |||
*New RBBB pattern may indicate lead in LV | |||
*Simulataneous depol of ventricles produces dominant R wave in V1 | |||
==Methods to Identify Manufacturer== | ==Methods to Identify Manufacturer== | ||
*Patient most often has a pocket card indicating manufacturer | |||
*Magnet types are specific to each model so use magnets to deactivate pulse generator | |||
*Manufactuer Hotline has patient database | |||
**Medtronic Inc. (1-800-328-2518) | |||
**St. Jude Medical Inc. (1-800-722-3774) | |||
*Manufactuer code on pulse generator is visible on Chest Xray | |||
==Plain Film Findings== | ==Plain Film Findings== | ||
*Obtain PA/Lateral Films to confirm pulse generator, manufacturer, lead placement/number/integrity | |||
*R atrial lead J shaped(tip medially on AP) entering right atrial appendage | |||
*RV leads point downward with tip between left spine and cardiac apex--lateral XR shows inferior and anterior | |||
*Coronary sinus lead- courses posteriorly on lateral XR | |||
*Extra leads may be appropriately abandoned and capped | |||
*ICD component appears as thickened shock coil | |||
==Pacemaker Malfunction== | ==Pacemaker Malfunction== | ||
===Problems with pocket=== | ===Problems with pocket=== | ||
*Infection | |||
**Most commonly Staphylococcus aureus or S. epidermidis | |||
*Hematoma | |||
**Typically occurs shortly after placement | |||
===Problems with leads=== | ===Problems with leads=== | ||
*Lead separation | |||
*Lead dislodgment may cause thrombosis or myocardial rupture | |||
*Lead infection can cause severe sepsis | |||
*Leads can cause tricuspid regurg, dx w/ TTE | |||
*Lead coiling (ie: Twiddler Syndrome) [[File:Twiddler Syndrome.png|thumb|Twiddler Syndrome after large pocket and pacemaker wires spinning on themselves]] | |||
==Failure to Capture== | ==Failure to Capture== | ||
*Def-delivery of pacing stimulus without depolarization | |||
*Functional- myocardium in refractory state or tissue reaction around lead insensitive | |||
*Pathologic- drugs, myocardial disease, lytes | |||
*Causes-lead dislodgement, fracture, perforation, insulation defect | |||
==Failure to Pace== | ==Failure to Pace== | ||
*Def-failure to deliver a stimulus to the heart (w/ or w/o capture) | |||
*Oversensing-most common cause-retrograde P’s, T’s, skeletal muscle myopotentials, | |||
*Crosstalk- type of oversensing-vent lead senses atrial pacing stim, and vent output inhibited | |||
==Failure to Sense== | ==Failure to Sense== | ||
*Signal sensed when myocardial depol sent up leads and into pacemaker, if voltage exceeds threshold, pacing inhibited(appropriately) | |||
*Most commonly break in lead/insulation, battery | |||
*Voltages of patient's intrinsic QRS complex is too low to be detected | |||
*New intrinsic arrhythmia, AMI, electrolyte abnormalities, lead separation, battery depletion | |||
===Runaway Pacing=== | ===Runaway Pacing=== | ||
*Physiologic electrical activity (T waves, muscle potentials) | |||
*External electromagnetic interference | |||
*Signals generated by interaction of different portions of the pacing system | |||
==Work-Up== | ==Work-Up== | ||
*CXR | |||
*ECG | |||
*Troponin | |||
*Interrogation | |||
==Management== | ==Management== | ||
*Pacemaker Mediated Tachycardia- dual chamber devices-PAC or PVC trigger with pacemaker in loop. Break with adenosine or magnet.<ref>EB Medicine- Sept 2014- Managing Pacemaker-Related Complications and Malfunctions in the Emergency Department </ref> | |||
*Use magnet to convert pacemaker to asynchronous mode if oversensing or runaway pacing | *Use magnet to convert pacemaker to asynchronous mode if oversensing or runaway pacing | ||
==Electromagnetic Interference== | ==Electromagnetic Interference== | ||
*Nonmedical- | |||
**Cell phones- do not interact w/ device | |||
**Airport security-may trigger alarm, no alteration of activity | |||
*Medical Sources | |||
**MRI—mostly safe, consult cards on device specific recs | |||
**Cardioversion- Use AP pads >8cm from device to minimize adverse effects | |||
==See Also== | ==See Also== | ||
Revision as of 12:48, 20 July 2015
Nomenclature
| I | II | III | IV | V |
|---|---|---|---|---|
| Chamber(s) paced | Chamber(s) sensed | Response to sensing | Rate modulation | Multisite pacing |
| O = None | O = None | O = None | O = None | O = None |
| A = Atrium | A = Atrium | T = Triggered | R = Rate modulation | A = Atrium |
| V = Ventricle | V = Ventricle | I = Inhibited | V = Ventricle | |
| D = Dual (A+V) | D = Dual (A+V) | D = Dual (T+I) | D = Dual (A+V) |
Indications
- Sinus Node Dysfunction-sinus bradycardia/arrest, sinoatrial block, chronotropic incompetence, a-fib.
- Acquired AV block- 3rd degree block and 2nd degree type II
- Chronic Bifascicular or Trifascicular block
- After Acute MI-high mortality with persistent AV block post MI
- Cardiac Resynchronization Therapy- Conduction delay (>150msec w/ mortality benefit) in chronic systolic heart failure further decreases EF, increases remodeling and increased MR.
- Neurocardiogenic Syncope and Carotid Sinus Syndrome
Expected ECG Patterns
- Absence of pacer artifact indicates intrinsic depolarization
- Pacing artifacts preceding depolarizations indicate successful pacing and capture
- Leads in RV apex produce LBBB pattern with appropriate discordance
- New RBBB pattern may indicate lead in LV
- Simulataneous depol of ventricles produces dominant R wave in V1
Methods to Identify Manufacturer
- Patient most often has a pocket card indicating manufacturer
- Magnet types are specific to each model so use magnets to deactivate pulse generator
- Manufactuer Hotline has patient database
- Medtronic Inc. (1-800-328-2518)
- St. Jude Medical Inc. (1-800-722-3774)
- Manufactuer code on pulse generator is visible on Chest Xray
Plain Film Findings
- Obtain PA/Lateral Films to confirm pulse generator, manufacturer, lead placement/number/integrity
- R atrial lead J shaped(tip medially on AP) entering right atrial appendage
- RV leads point downward with tip between left spine and cardiac apex--lateral XR shows inferior and anterior
- Coronary sinus lead- courses posteriorly on lateral XR
- Extra leads may be appropriately abandoned and capped
- ICD component appears as thickened shock coil
Pacemaker Malfunction
Problems with pocket
- Infection
- Most commonly Staphylococcus aureus or S. epidermidis
- Hematoma
- Typically occurs shortly after placement
Problems with leads
- Lead separation
- Lead dislodgment may cause thrombosis or myocardial rupture
- Lead infection can cause severe sepsis
- Leads can cause tricuspid regurg, dx w/ TTE
- Lead coiling (ie: Twiddler Syndrome)
Failure to Capture
- Def-delivery of pacing stimulus without depolarization
- Functional- myocardium in refractory state or tissue reaction around lead insensitive
- Pathologic- drugs, myocardial disease, lytes
- Causes-lead dislodgement, fracture, perforation, insulation defect
Failure to Pace
- Def-failure to deliver a stimulus to the heart (w/ or w/o capture)
- Oversensing-most common cause-retrograde P’s, T’s, skeletal muscle myopotentials,
- Crosstalk- type of oversensing-vent lead senses atrial pacing stim, and vent output inhibited
Failure to Sense
- Signal sensed when myocardial depol sent up leads and into pacemaker, if voltage exceeds threshold, pacing inhibited(appropriately)
- Most commonly break in lead/insulation, battery
- Voltages of patient's intrinsic QRS complex is too low to be detected
- New intrinsic arrhythmia, AMI, electrolyte abnormalities, lead separation, battery depletion
Runaway Pacing
- Physiologic electrical activity (T waves, muscle potentials)
- External electromagnetic interference
- Signals generated by interaction of different portions of the pacing system
Work-Up
- CXR
- ECG
- Troponin
- Interrogation
Management
- Pacemaker Mediated Tachycardia- dual chamber devices-PAC or PVC trigger with pacemaker in loop. Break with adenosine or magnet.[2]
- Use magnet to convert pacemaker to asynchronous mode if oversensing or runaway pacing
Electromagnetic Interference
- Nonmedical-
- Cell phones- do not interact w/ device
- Airport security-may trigger alarm, no alteration of activity
- Medical Sources
- MRI—mostly safe, consult cards on device specific recs
- Cardioversion- Use AP pads >8cm from device to minimize adverse effects
See Also
References
- ↑ Bernstein AD. et al. The revised NASPE/BPEG generic code for antibradycardia, adaptive-rate, and multisite pacing. North American Society of Pacing and Electrophysiology/British Pacing and Electrophysiology Group. Pacing Clin Electrophysiol 2002 Feb; 25(2) 260-4. lmid:11916002
- ↑ EB Medicine- Sept 2014- Managing Pacemaker-Related Complications and Malfunctions in the Emergency Department