Pacemakers and ICD ’ s Dr.Gharibzadeh Alaleh Rashidnasab.
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Transcript of Pacemakers and ICD ’ s Dr.Gharibzadeh Alaleh Rashidnasab.
PacemakersPacemakersandand
ICDICD’’ss
Dr.GharibzadehDr.Gharibzadeh
Alaleh RashidnasabAlaleh Rashidnasab
SCD most common cause of death SCD most common cause of death
Sudden Cardiac DeathSudden Cardiac Death
Sudden Cardiac DeathSudden Cardiac Death
Death by an arrhythmia:Death by an arrhythmia:
BradycardiaBradycardia
TachycardiaTachycardia
Atrial FibrillationAtrial Fibrillation
Ventricular FibrillationVentricular Fibrillation
BradycardiaBradycardia
Sinus node discharges at a rate < 60 bpmSinus node discharges at a rate < 60 bpm
Decreased CO may occur Decreased CO may occur
TachycardiaTachycardia
Discharge rate from the sinus node is Discharge rate from the sinus node is increased and is > 100 bpmincreased and is > 100 bpm
Increased myocardial oxygen consumption Increased myocardial oxygen consumption is associated with increased HRis associated with increased HR
Atrial FibrillationAtrial Fibrillation
Total disorganization of atrial activity without effective Total disorganization of atrial activity without effective atrial contractionatrial contraction
Can often result in decrease in CO because of Can often result in decrease in CO because of ineffective atrial contractions and rapid ventricular ineffective atrial contractions and rapid ventricular responseresponse
Goals are decreased in ventricular response and Goals are decreased in ventricular response and conversion to sinus rhythmconversion to sinus rhythm
Ventricular FibrillationVentricular Fibrillation
Severe derangement of the heart rhythm Severe derangement of the heart rhythm characterized on ECG by irregular undulations of characterized on ECG by irregular undulations of varying contour and amplitudevarying contour and amplitude
No effective contraction or CO occursNo effective contraction or CO occurs
If untreated, patient will dieIf untreated, patient will die
TreatmentsTreatments
Drug therapyDrug therapy
DefibrillatorsDefibrillators
PacemakersPacemakers
ICDsICDs(Implantable Cardioverter Defibrillator):(Implantable Cardioverter Defibrillator):
ICD Therapy consists of pacing, cardioversion, and ICD Therapy consists of pacing, cardioversion, and defibrillation therapies to treat brady and tachy defibrillation therapies to treat brady and tachy arrhythmiasarrhythmias
Historical PerspectiveHistorical Perspective
1905 1905 –– Einthoven Einthoven Published first two human AV block using string Published first two human AV block using string
galvanometergalvanometer
1958 1958 –– Senning and Elmqvist Senning and Elmqvist Asynchronous (VVI) pacemaker implanted by Asynchronous (VVI) pacemaker implanted by
thoracostomy and functioned for 3 hoursthoracostomy and functioned for 3 hours Arne LarssonArne Larsson
First pacemaker patientFirst pacemaker patientUsed 23 pulse generators and 5 electrode systemsUsed 23 pulse generators and 5 electrode systemsDied 2001 at age 86 of cancerDied 2001 at age 86 of cancer
Historical PerspectiveHistorical Perspective
1960 1960 –– First atrial triggered pacemaker First atrial triggered pacemaker
1964 1964 –– First on demand pacemaker (DVI) First on demand pacemaker (DVI)
1977 1977 –– First atrial and ventricular demand First atrial and ventricular demand pacing (DDD)pacing (DDD)
1980 1980 –– Griffin published first successful Griffin published first successful pacemaker intervention for pacemaker intervention for supraventricular tachycardiassupraventricular tachycardias
Historical PerspectiveHistorical Perspective
1981 1981 –– Rate responsive pacing by QT Rate responsive pacing by QT interval, respiration, and movementinterval, respiration, and movement
1994 1994 –– Cardiac resynchronization pacing Cardiac resynchronization pacing
1998 1998 –– Automatic capture detection Automatic capture detection
NowNow Approximately 3 million with pacemakersApproximately 3 million with pacemakers Approximately 1 million with ICD deviceApproximately 1 million with ICD device
19801980Large devices -Large devices -Abdominal siteAbdominal site
First human implantsFirst human implants
Thoracotomy, multiple incisionsThoracotomy, multiple incisions
Primary implanter= cardiac surgeonPrimary implanter= cardiac surgeon
General anesthesiaGeneral anesthesia
Long hospital staysLong hospital stays
Complications from major surgeryComplications from major surgery
Perioperative mortality up to 9%Perioperative mortality up to 9%
Nonprogrammable therapyNonprogrammable therapy
High-energy shock onlyHigh-energy shock only
Device longevity Device longevity 1.5 years 1.5 years
Fewer than 1,000 implants/yearFewer than 1,000 implants/year
TodayTodaySmall devices - Small devices -
Pectoral sitePectoral site
First-line therapy for VT/VF patientsFirst-line therapy for VT/VF patients Treatment of atrial arrhythmiasTreatment of atrial arrhythmias Cardiac resynchronization therapy for HFCardiac resynchronization therapy for HF Transvenous, single incisionTransvenous, single incision Local anesthesia; conscious sedationLocal anesthesia; conscious sedation Short hospital stays and few complicationsShort hospital stays and few complications Perioperative mortality < 1%Perioperative mortality < 1% Programmable therapy optionsProgrammable therapy options Single- or dual-chamber therapySingle- or dual-chamber therapy Battery longevity up to 9 yearsBattery longevity up to 9 years More than 100,000 implants/yearMore than 100,000 implants/year
Evolution of ICD Therapy: Evolution of ICD Therapy:
Pacemaker BasicsPacemaker Basics
Provides electrical stimuli Provides electrical stimuli to cause cardiac to cause cardiac contraction when intrinsic contraction when intrinsic cardiac activity is cardiac activity is inappropriately slow or inappropriately slow or absentabsent
Sense intrinsic cardiac Sense intrinsic cardiac electric potentialselectric potentials
A Brief History of PacemakersA Brief History of Pacemakers
ICD BasicsICD BasicsDesigned to treat a cardiac tachydysrythmiaDesigned to treat a cardiac tachydysrythmiaAn external programmer is used to monitor and An external programmer is used to monitor and access the device parameters and therapies for each access the device parameters and therapies for each patient.patient.
Performs cardioversion/defibrillationPerforms cardioversion/defibrillation Ventricular rate exceeds programmed cut-off rateVentricular rate exceeds programmed cut-off rateATP (antitachycardia pacing)ATP (antitachycardia pacing) Overdrive pacing in an attempt to terminate Overdrive pacing in an attempt to terminate
ventricular tachycardiasventricular tachycardiasSome have pacemaker function (combo devices)Some have pacemaker function (combo devices)
209 cc 120 cc 80 cc 80 cc 72 cc 54 cc
62 cc 49 cc 39.5 cc 39.5 cc 36 cc38 cc39.5 cc
Implantable Defibrillators (1989-2003)
Pacemaker and ICD BasicsPacemaker and ICD Basics
Pulse GeneratorsPulse Generators Placed submuscularlyPlaced submuscularly Connected to leadsConnected to leads BatteryBattery
Most commonly lithium-iodide typeMost commonly lithium-iodide type
Life span 5 to 8 yearsLife span 5 to 8 years
Output voltage decreases graduallyOutput voltage decreases gradually Makes sudden battery failure unlikelyMakes sudden battery failure unlikely
Pacemaker and ICD BasicsPacemaker and ICD Basics
AsynchronousAsynchronous Fixed rateFixed rate Impulse produced at a set rateImpulse produced at a set rate No relation to patients intrinsic cardiac activityNo relation to patients intrinsic cardiac activity
Pacemaker and ICD BasicsPacemaker and ICD Basics
SynchronousSynchronous Demand modeDemand mode Sensing circuit searches for intrinsic Sensing circuit searches for intrinsic
depolarization potentialdepolarization potential If absent, a pacing response is generatedIf absent, a pacing response is generated Can mimic intrinsic electrical activity pattern of Can mimic intrinsic electrical activity pattern of
the heartthe heart
Pacemaker Lead SystemPacemaker Lead System
Endocardial leads placed via central Endocardial leads placed via central accessaccess Placed in right ventricle and/or atriaPlaced in right ventricle and/or atria
Fixed to the endocardium via screws or Fixed to the endocardium via screws or tinestines
Experimental pacing systemsExperimental pacing systems 2 atrial leads (minimize afib)2 atrial leads (minimize afib) Biventricular pacingBiventricular pacing
Pacemaker IndicationsPacemaker Indications
Absolute indicationsAbsolute indications Sick sinus syndromeSick sinus syndrome Symptomatic sinus bradycardiaSymptomatic sinus bradycardia Tachy-brady syndromeTachy-brady syndrome Afib with slow ventricular responseAfib with slow ventricular response 33rdrd degree heart block degree heart block Chronotropic incompetenceChronotropic incompetence
Inability to increase heart rate to match exerciseInability to increase heart rate to match exercise
ICD IndicationsICD Indications
GenerallyGenerally Used in cases where there was a previous Used in cases where there was a previous
cardiac arrestcardiac arrest Or, patients with undetermined origin or Or, patients with undetermined origin or
continued VT or VF despite medical continued VT or VF despite medical interventionsinterventions
Pacemaker ComplicationsPacemaker Complications
EKG abnormalities due toEKG abnormalities due to Failure to outputFailure to output Failure to captureFailure to capture Sensing abnormalitiesSensing abnormalities
Pacemaker Failure to OutputPacemaker Failure to Output
DefinitionDefinition No pacing spike present despite indication to No pacing spike present despite indication to
pacepace
EtiologyEtiology Battery failure, lead fracture, break in lead Battery failure, lead fracture, break in lead
insulation, oversensing, poor lead connection, insulation, oversensing, poor lead connection, ““cross-talkcross-talk””
Atrial output is sensed by ventricular leadAtrial output is sensed by ventricular lead
Pacemaker Failure to CapturePacemaker Failure to Capture
DefinitionDefinition Pacing spike is not followed by either an atrial Pacing spike is not followed by either an atrial
or ventricular complexor ventricular complex
EtiologyEtiology Lead fracture or dislodgement, break in lead Lead fracture or dislodgement, break in lead
insulation, elevated pacing threshold, MI at insulation, elevated pacing threshold, MI at lead tip, drugs, metabolic abnormalities, lead tip, drugs, metabolic abnormalities, cardiac perforation, poor lead connectioncardiac perforation, poor lead connection
Pacemaker Sensing Pacemaker Sensing AbnormalitiesAbnormalities
OversensingOversensing Senses noncardiac electrical activity and is Senses noncardiac electrical activity and is
inhibited from correctly pacinginhibited from correctly pacing EtiologyEtiology
Muscular activity (diaphragm or pecs), EMI, cell Muscular activity (diaphragm or pecs), EMI, cell phone held within 10cm of pulse generatorphone held within 10cm of pulse generator
UndersensingUndersensing Incorrectly misses intrinsic depolarization and Incorrectly misses intrinsic depolarization and
pacespaces EtiologyEtiology
Poor lead positioning, lead dislodgement, magnet Poor lead positioning, lead dislodgement, magnet application, low battery states, MIapplication, low battery states, MI
ICD ComplicationsICD Complications
Similar to pacemaker complicationsSimilar to pacemaker complications Sensing and pacing failuresSensing and pacing failures Inappropriate cardioversionInappropriate cardioversion Ineffective cardioversion/defibrillationIneffective cardioversion/defibrillation
ICD Sensing failuresICD Sensing failures
Similar to pacmakersSimilar to pacmakers OversensingOversensing UndersensingUndersensing
ICD Inappropriate CardioversionICD Inappropriate Cardioversion
Most frequent complicationsMost frequent complicationsProvokes pain and anxiety in ptsProvokes pain and anxiety in ptsConsider whenConsider when Pt is in afibPt is in afib Received multiple shocks in rapid successionReceived multiple shocks in rapid succession
EtiologyEtiology Afib, T-wave oversensing, lead fracture, insulation Afib, T-wave oversensing, lead fracture, insulation
breakage, MRI, EMIbreakage, MRI, EMI
ICD Inappropriate CardioversionICD Inappropriate Cardioversion
TreatmentTreatment Magnet over ICD inhibits further shocksMagnet over ICD inhibits further shocks Does NOT inhibit bradycardiac pacingDoes NOT inhibit bradycardiac pacing
NoteNote Some older devices produce beep with each QRSSome older devices produce beep with each QRS If left on for >30 seconds, ICD disabled and continous If left on for >30 seconds, ICD disabled and continous
beepbeep To reactivate, lift off magnet and then replace for > 30 To reactivate, lift off magnet and then replace for > 30
seconds, beep will return with each QRSseconds, beep will return with each QRS
ICD Failure to Deliver ICD Failure to Deliver CardioversionCardioversion
EtiologyEtiology Failure to sense, lead fracture, EMI, Failure to sense, lead fracture, EMI,
inadvertent ICD deactivationinadvertent ICD deactivation
ManagementManagement External defibrillation and cardioversionExternal defibrillation and cardioversion
Do not withhold therapy for fear of damaging ICDDo not withhold therapy for fear of damaging ICDIf ptIf pt’’s internal defibrillator activates during chest s internal defibrillator activates during chest compressions, you may feel a mild shock (no compressions, you may feel a mild shock (no reports of deaths related to this)reports of deaths related to this)
Antidysrhymthic medicationsAntidysrhymthic medications
ICD Ineffective CardioversionICD Ineffective Cardioversion
EtiologyEtiology Inadequate energy outputInadequate energy output Rise in the defibrillation thresholdRise in the defibrillation threshold Lead fractureLead fracture Insulation breakageInsulation breakage
Electromagnetic InterferenceElectromagnetic Interference
Can interfere with function of pacemaker Can interfere with function of pacemaker or ICDor ICD
Device misinterprets the EMI causingDevice misinterprets the EMI causing Rate alterationRate alteration Sensing abnormalitiesSensing abnormalities Asynchronous pacingAsynchronous pacing Noise reversionNoise reversion ReprogrammingReprogramming
Electromagnetic InterferenceElectromagnetic Interference
ExamplesExamples Metal detectorsMetal detectors Cell phonesCell phones High voltage power linesHigh voltage power lines Some home appliances (microwave)Some home appliances (microwave)
Electromagnetic InterferenceElectromagnetic Interference
Intensity of electromagnetic field Intensity of electromagnetic field decreases inversely with the square of the decreases inversely with the square of the distance from the sourcedistance from the source
Newer pacemakers and ICDs are being Newer pacemakers and ICDs are being built with increased internal shieldingbuilt with increased internal shielding
Future ICD TechnologyFuture ICD Technology
Enhanced automaticityEnhanced automaticity:: Device software that suggests programming options Device software that suggests programming options
to the clinician based on the patient’s history and to the clinician based on the patient’s history and demographicsdemographics
Continued reductions in device sizeContinued reductions in device size:: Will require advancements in battery, capacitor and Will require advancements in battery, capacitor and
circuitry technology and/or decreasing the delivered circuitry technology and/or decreasing the delivered energy output.energy output.
Future ICD TechnologyFuture ICD Technology
Enhanced diagnostics:Enhanced diagnostics: Monitoring of the progression of both arrhythmias and Monitoring of the progression of both arrhythmias and
concomitant cardiac conditionsconcomitant cardiac conditions
Enhanced lead technology:Enhanced lead technology: Thinner leads with increased diagnostic capabilities, Thinner leads with increased diagnostic capabilities,
e.g., pressure sensing.e.g., pressure sensing.
Patient follow-up modifications:Patient follow-up modifications: Broadly available programmer technology that Broadly available programmer technology that
enables remote transfer of data, reducing the need for enables remote transfer of data, reducing the need for in-clinic visits. in-clinic visits.
Thank youThank you