Mod V: Cardovascular Implantable Electronic Devices (CIED)

Question 1

_{Cardovascular Implantable Electronic Devices (CIED)}

Cardovascular Implantable Electronic Devices (CIED) are used for the Treatment & management of:

Answer 1

Cardiac conduction & Arrhythmia problems

Symptomatic bradycardia

^{(including that resulting from sinus node dysfunction)}

Atrioventricular (AV) conduction block

^{(after catheter ablation of the AV node or junction)}

Question 2

_{Perioperative mgnt of patients with Cardovascular Implantable Electronic Devices (CIED)}

Pacing can be provided in several ways, including

Answer 2

Application of external pacing pads

Urgent insertion of a transvenous pacing lead via central venous access

Implantation of permanent intracardiac leads along with a pulse generator.

_{Regardless of how it is provided, pacemaker programming (and therefore pacemaker function) must always be individualized to the needs of the individual patient}

Question 3

_{Perioperative mgnt of patients with Cardovascular Implantable Electronic Devices (CIED)}

The ‘best’ perioperative care of a patient with a CIED usually comes from the recommendations from which individual or team?

Answer 3

The physician/care team who usually monitor/manage the CIED (the CIED ‘team’)

Such recommendations should routinely be sought in advance whenever feasible.

Question 4

_{Perioperative mgnt of patients with Cardovascular Implantable Electronic Devices (CIED)}

Electronic device that delivers electrical stimulation to heart

Answer 4

Cardovascular Implantable Electronic Devices (CIED)

Question 5

_{Perioperative mgnt of patients with Cardovascular Implantable Electronic Devices (CIED)}

Pacing can be delivered to

Answer 5

a single chamber (atrium or ventricle only),

dual chambers (atrium and ventricle), or

multiple chambers (in biventricular pacing)

Question 6

_{Perioperative mgnt of patients with Cardovascular Implantable Electronic Devices (CIED)}

Leads - Pacing can use either:

Answer 6

unipolar or bipolar leads.

Over the last 15 yr, bipolar leads have been predominantly used. With a bipolar lead, both the cathode and anode are present on the lead itself and thus the distance between them is much smaller than with a unipolar lead (where the pulse generator functions as the anode). The advantage of the bipolar configuration is reduced susceptibility to electromagnetic interference (EMI).

Question 7

_{Cardovascular Implantable Electronic Devices (CIED)}

How do Cardovascular Implantable Electronic Devices (CIED) function?

Answer 7

Sensing intrinsic cardiac electrical potentials

device can sense intrinsic electrical activity in the chamber where the lead is placed to either inhibit or trigger pacing in that chamber

If no spontaneous depolarization of the chamber is sensed within the programmed limits, the device will deliver a pacing stimulus

If a spontaneous chamber depolarization occurs and is sensed, the device will inhibit the delivery of a pacing stimulus and wait for a subsequent depolarization during the next pre-set time interval.

A dual-chamber pacing mode allows for both sensing and subsequent triggering or inhibition of pacing in one or both chambers

Question 8

_{Implantable Pacemaker System}

What are the components of a pacemaking system?

Answer 8

Impulse generator

Leads

^{(carry the electrical impulse to the patient’s heart)}

Question 9

_{Implantable Pacemaker System}

What’s the function of PM leads?

Answer 9

Insulated wires tha deliver electrical impulses from the pulse generator to the heart

Leads carry the electrical impulse to the patient’s heart

Transmit electrical signals from the heart to the pulse generator

Question 10

_{Implantable Pacemaker System}

How are PM leads connected to the heart chambers?

Answer 10

Through the vena cava (transvenous leads), or

Sewn onto the surface of the heart (epicardial leads)

Question 11

_{Implantable Pacemaker System}

In terms of polarity what are the different types of PM leads?

Answer 11

Unipolar leads (one electrode per lead)

^{Because two electrodes are required to complete a circuit, the second electrode in a unipolar configuration is the metal generator case}

^{Use of the case as an electrode requires that the generator pocket be devoid of gas, and electrical continuity has reportedly been disrupted by the use of nitrous oxide​}

Bipolar leads (two electrodes per lead), or

Multipolar leads (multiple electrodes and wires contained within one lead with connections in multiple chambers)

Pacemaker leads are generally placed in the right atrial (RA) appendage, right ventricle (RV), or, in a dual-chamber device, both

Question 12

_{Implantable Pacemaker System}

PM leads with pacing polarity are more sensitive to the effects of EMI?

Answer 12

PMs with unipolar leads are more sensitive to the effects of EMI

Question 13

_{Implantable Pacemaker System}

Most pacemaking systems (except older Autocapture devices from St. Jude Medical) pace in which pacing polarity mode? why?

Answer 13

Bipolar mode

because bipolar pacing usually requires less energy

Question 14

_{Implantable Pacemaker System}

Which sensing polarity modality is more resistant to interference from muscle artifacts or stray electromagnetic fields

Answer 14

Bipolar sensing

Question 15

_{Implantable Pacemaker System}

What are Indications for permanent pacing?

Answer 15

Sinus node disease

^{(Symptomatic diseases of impulse formation)}

Atrioventricular nodal disease

^{(Symptomatic diseases of impulse conduction)}

Long QT syndrome

Hypertrophic obstructive cardiomyopathy

Dilated cardiomyopathy

Question 16

_{Implantable Pacemaker System}

Where are Implantable Pacemaker System pulse generator usually implanted in the body?

Answer 16

Infraclavicular region

SubCutaneously

Question 17

_{Implantable Pacemaker System}

What are the components of Implantable pulse generator of a Implantable Pacemaker System?

Answer 17

Power source

Circuitry

Question 18

_{Implantable Pacemaker System}

How long does the Power source of Implantable pulse generator last?

Answer 18

5 to 15 years

Question 19

_{Implantable Pacemaker System}

What’s the function of an Implantable pulse generator circuitry?

Question 20

_{Implantable Pacemaker System}

What’s the function of a pacemaker electrode?

Answer 20

Conductor located at the end of the lead

Delivers the impulse to the heart

Question 21

_{Implantable Pacemaker System}

How does Myocardial tissue participate in the Implantable Pacemaker System?

Answer 21

Receives electrical impulse from the lead and stimulates the heart

Produces an electrical signal that the lead senses, or “sees”

Question 22

_{Implantable Pacemaker System}

Graphical representation of a modern pacemaker: see picture

Answer 22

Graphical representatio of a modern pacemaker

Note: Generator, RA an RV leads

Green lead => BiVent PCMkr

Question 23

_{Implantable Pacemaker System - Important Definitions}

The process whereby a pcm spike generates a mechanical contraction (Ppcm spike a/w QRS complex) is known as ?

Answer 23

Capture

Question 24

_{Implantable Pacemaker System - Important Definitions}

The process whereby the PCM fails to deliver sufficient energy to the myocardium to produce a depolarization is also known as:

Answer 24

Loss of Capture

The PCM sees other things, fires but does not generate a QRS

The question you must ask is “why?”

Question 25

_{Implantable Pacemaker System - Important Definitions} What are causes of "Loss of Capture"?

Answer 25

Inappropriate **output** setting Increased **resistance to conduction** _Dislodged/fractured lead_ **Hypokalemia** ^{Cardiac tissue is refractory /hyperpolarized Hypokalemia lowers the RMP which pushes the pacing threshold by} **Faulty cable connection**

Question 26

_{Implantable Pacemaker System - Important Definitions} Minimum amount of energy required to consistently capture the myocardium and cause depolarization/contraction

Answer 26

**Pacing Threshold** Measured by amplitude (mA or V) & duration (mS)

Question 27

_{Implantable Pacemaker System - Factors Affecting Pacemaker Threshold} What are the things you can affect? How can you increase pcm threshold? aka (make it more difficult to pace)

Answer 27

Acidosis - Hyperglycemia - Hyperoxemia Hypokalemia - Hypernatremia B-blockers - Procainamide (toxic dose) - Mineralocorticoids Myocardial scar tissue

Question 28

_{Implantable Pacemaker System - Factors Affecting Pacemaker Threshold} What are the things you can affect? How can you decrease pcm threshold? aka (make it easier to pace)

Answer 28

Stress - Hypoxemia - Hyperkalemia Ephedrine - Glucocorticoids

Question 29

_{Implantable Pacemaker System - Important Definitions} undersensing (intrinsic activity is not detected)

Answer 29

**Undersensing** ## Footnote Cuases over pacing – sense activity and tries to oeverpace… why?

Question 30

_{Implantable Pacemaker System - Important Definitions} Causes of Undersensing - senses activity and tries to oeverpace… why?

Answer 30

Battery depletion Decreased QRS voltage Fusion beat Dislodged/fractured lead Inappropriate sensitivity setting Myocardial infarction

Question 31

_{Implantable Pacemaker System - Important Definitions} ventricular activity in the absence of true electrical systoles is also known as: (“detection” of events unrelated to intrinsic activity) Occurs when pcm sense a potential (em interfere, p-wave, etc) but refuses to fire Oversensing but underfiring Really problematic w/ electromagn interference

Answer 31

**Oversensing**

Question 32

Generic Codes for Pacemakers

Answer 32

Generic Codes for Pacemakers Revised recently North Am and Britisk EP society

Question 33

_{Generic Codes for Pacemakers - Types of Pacing Modes} Simple form of fixed rate pacemaker Discharges at a preset rate irrespective of the intrinsic heart rate

Answer 33

Asynchronous Pacing AOO → Asynchronous atrial only pacing VOO → Asynchronous ventricular only pacing DOO → Asynchronous AV sequential pacing

Question 34

_{Types of Pacing Modes} Asynchronous Pacing - Competes with the patient’s intrinsic rhythm - Provoke an

Answer 34

R on T phenomenon → induction of tachyarrhythmias

Question 35

_{Generic Codes for Pacemakers - Types of Pacing Modes} Asynchronous Modes - AOO

Answer 35

AOO

Question 36

_{Generic Codes for Pacemakers - Types of Pacing Modes} Asynchronous Modes - VOO

Answer 36

VOO

Question 37

_{Generic Codes for Pacemakers - Types of Pacing Modes} Asynchronous Modes - DOO

Answer 37

DOO

Question 38

_{Types of Pacing Modes} Single Chamber Atrial Pacing (AAI)

Answer 38

Single Chamber Atrial Pacing (AAI)

Question 39

_{Types of Pacing Modes} Single Chamber Ventricular Pacing (VVI)

Answer 39

Single Chamber Ventricular Pacing (VVI)

Question 40

_{Types of Pacing Modes} Two leads One lead implanted in the atrium - One lead implanted in the ventricle - Atrium is stimulated first to contract, then after an adjustable PR interval ventricle is stimulated to contract

Answer 40

Dual Chamber AV Sequential Pacing | (DDD, DVI, DDI, & VDD)

Question 41

_{Types of Pacing Modes - Dual Chamber AV Sequential Pacing} Benefefits of Dual Chamber AV Sequential Pacing

Answer 41

Preserve AV synchrony Most common modes used today Goal is to Preserve AV synchrony

Question 42

_{Types of Pacing Modes - Dual Chamber AV Sequential Pacing} Indication for Dual Chamber AV Sequential Pacing

Answer 42

AV block, carotid sinus syncope, & sinus node disease

Question 43

_{Types of Pacing Modes - Dual Chamber AV Sequential Pacing} A Benefefit of Dual Chamber AV Sequential Pacing is that it preserves AV synchrony. Why is that important?

Answer 43

Why is AV synchrony important: atrial kick, R-on-T

Question 44

Preoperative Evaluation

Answer 44

Coexisting disease ^{High dose opioid (fent) can cuase bradycardia} History vertigo, syncope, light headedness, or return of pre-pacemaker symptoms ^{Know the hx} Optimize Electrolytes Obtain CXR ^{(if no information on device type)} EKG ^{(to determine that pcm is firing)} Pacemaker interrogation ^{(must be performed w/in 1 year – available – can be done by phone)}

Question 45

_{Electromagnetic Interference (EMI)} Measures to minimize effect of Electromagnetic Interference (EMI)

Answer 45

Bipolar cautery vs. monopolar if possible Monopolar cautery use

Question 46

_{Electromagnetic Interference (EMI)} Monopolar cautery use (Since we cannot control use of stuffs like Bovie)

Answer 46

Grounding plate close to surgical site & as far away from pacemaker as possible Do not use within 15 cm of pacemaker ^{Procedures above the umbilicus the most risky} Limit bursts to 1 sec every 10 sec Monitor cardiac rhythm/ peripheral pulse with pulse oximeter or arterial waveform (EKG affected by interference) ^{Palpate pulse to ensure mechanical is occuring} Have alternative temporary pacing methods available in OR ^{Most preferred} Emergency drugs: atropine/isoproterenol Magnet? ^{could switch pcm to asynchronous mode}

Question 47

Intraoperative management of severe bradycardia:

Answer 47

1. Administer O2 & control airway 2. Give Atropine 3. Give Isoproterenol 4. Place magnet over pacemaker (convert demand to asynchronous) 5. Initiate transcutaneous external pacing

Question 48

Postoperative Management

Answer 48

Any pacemaker that was reprogrammed for the operating room should be reset appropriately ^{Any pacemaker that was reprogrammed (magnet applied, etc) for the operating room should be reset appropriately by proper qualified provider} Have the device interrogated by a competent authority For non reprogrammed devices most manufacturers recommend interrogation to ensure proper functioning and remaining battery life if any electrocautery was used

Question 49

Implantable Cardioverter Defibrillators History:

Answer 49

1985: Implantable cardioverter defibrillators (ICD’s) Treat fatal tachyarrhythmias

Question 50

Implantable Cardioverter Defibrillators Current:

Answer 50

Technologic advances revolutionized pacemakersCurrent combined pacemaker/ICD device most pcm today are this way

Question 51

Implantable Cardiac Defibrillator Mechanism of Action:

Answer 51

ICD’s measure each R-R interval The internal computer chooses antitachycardia pacing or shock depending upon the presentation and device programming Most ICD’s are programmed to reconfirm VT or VF after charging to prevent inappropriate therapy Typically ICD’s deliver 6-18 shocks per event Most ICD’s will begin pacing if the R-R interval is too long

Question 52

_{Implantable Cardiac Defibrillator} Indications:

Answer 52

Ventricular Tachycardia Ventricular Fibrillation EF≤35% Hypertrophic Cardiomyopathy Awaiting heart transplant Long QT syndrome Arrhythmogenic Right ventricular Dysplasia Brugada syndrome (RBBB, S-T segment elevation in leads V1-V3)

Question 53

Implantable Cardiac Defibrillator Most devices will suspend tachydysrhythmia detection

Answer 53

True

Question 54

Implantable Cardiac Defibrillator In general magnets will not affect the brady pacing mode or rate

Answer 54

True

Question 55

Implantable Cardiac Defibrillator Interrogating the device and calling the manufacturer is the most reliable method to determine magnet response

Answer 55

True | (ICD must be interrogated w/in 6 mos)

Question 56

Implantable Cardiac Defibrillator Preanesthetic evaluation:

Answer 56

Evaluate and optimize co-morbid diseases Every ICD patient should undergo ICD interrogation Disabling of antitachycardia therapy (If no risk, may not have todo anythin)

Question 57

Implantable Cardiac Defibrillator Deactivation Guide to ICD

Answer 57

Place magnet over device Do you hear beeping ?

Question 58

Implantable Cardiac Defibrillator - Deactivation Guide to ICD Place magnet over device Do you hear beeping ? Yes:

Answer 58

Hold magnet over device for at least 30 sec

Question 59

Implantable Cardiac Defibrillator - Deactivation Guide to ICD Place magnet over device Do you hear beeping ? No:

Answer 59

Check magnet position Contact ICD programmer if still not heard If no beep tone, must be reinterrogated by qualified personel

Question 60

_{Implantable Cardiac Defibrillator - Deactivation Guide to ICD} Place magnet over device You hear beeping You Hold magnet over device for at least 30 sec Did beeping tone change to continuous tone? No:

Answer 60

Device can not be turned off with magnet. ICD programmer required Magnet will inhibit tachy therapy & can be taped over ICD to continue inhibition Tones will continue as long as magnet properly positioned Upon removal, device will return to normal operation

Question 61

_{Implantable Cardiac Defibrillator - Deactivation Guide to ICD} Place magnet over device You hear beeping You Hold magnet over device for at least 30 sec Did beeping tone change to continuous tone? Yes:

Answer 61

Device is off and will not deliver tachy therapy. Brady therapy not effected

Question 62

Implantable Cardiac Defibrillator - Deactivation Guide to ICD How do you turn a deactivated device back on?

Answer 62

Apply magnet for 30 sec. Listen for tone to change from Continuous to beeping tone If no beep tone, must be reinterrogated by qualified personel

Question 63

_{Implantable Cardiac Defibrillator} Intraoperative Management of Implantable Cardiac Defibrillator

Answer 63

ECG Monitoring Ability to deliver external cardioversion or defibrillation during the time of ICD disablement If cardioversion or defibrillation is needed the pads should be placed to avoid the pulse generator ICD’s should be disabled prior to insertion of a central line to prevent inappropriate shock and possible ICD failure

Question 64

_{Electromagnetic Interference (EMI) - Defibrillation/Pacing} Position paddles

Answer 64

Position paddles as far away from CIED site as possible Anterior to posterior positioning optimal Very important in emergency Could use ant lateral if unable to get posterior

Question 65

Implantable Cardiac Defibrillator Post op Evaluation:

Answer 65

ICD must be interrogated and re-enabled Pacing parameters should be checked and reset as necessary

Question 66

_{Pre- and Intraoperative management of patients w/ a pacemaker or ICD} Before planned surgery or other interventional procedure, obtain

Answer 66

Recent interrogation report regarding CIED function (typically, this should be w/in 6 mo for an ICD, and 12 mo for a PM)

Question 67

_{Pre- and Intraoperative management of patients w/ a pacemaker or ICD} Before planned surgery or other interventional procedure, what must you do if a recent report showing normal function of the CIED is not available?

Answer 67

Consult the CIED physician/ care team for a perioperative management plan, and to arrange for CIED interrogation Note whether the CIED is an ICD or a PM

Question 68

_{Pre- and Intraoperative management of patients w/ a pacemaker or ICD} What must you do if Electromagnetic Interference (EMI) is likely to occur in the vicinity of the CIED, the CIED is either an ICD\* or a PM, and the pt is pacing dependent?

Answer 68

_If the device CIED is an ICD_ Consult the CIED physician/care team to disable antitachycardia therapy immediately before the procedure In some cases, this must be accomplished w/ a programing machine In other cases, this may be accomplishd w/ a magnet _For both ICD an PM_ Consult the CIED physician/care team to change the CIED (ICD or PM) to an asynchronous mode immediately before the procedure In some cases. this must be accomplished w/ a programing machine In other cases, this may be accomplished w/ a magnet If device is an ICD, the pacing made cannit be chnaged w/ a magnet At the conclusion of the surgical or other interventional procedure, proceed to post operative managment

Question 69

_{Pre- and Intraoperative management of patients w/ a pacemaker or ICD} What must you do if Electromagnetic Interference (EMI) is likely to occur in the vicinity of the CIED, the CIED is an ICD

Answer 69

Consult the CIED physician/care team to disable antitachycardia therapy immediately before the procedure In some cases, this must be accomplished w/ a programing machine In other cases, this may be accomplishd w/ a magnet

Question 70

_{Pre- and Intraoperative management of patients w/ a pacemaker or ICD} What must you do if Electromagnetic Interference (EMI) is likely to occur in the vicinity of the CIED, the CIED is either an ICD or a PM, but the pt is NOT pacing dependent?

Answer 70

At the conclusion of the surgical or other interventional procedure, proceed to postoperative management

Question 71

_{Post-operative management of patients w/ a pacemaker or ICD} What is the most important question you must ask?

Answer 71

Was the CIED (ICD or PM) programmed for the surgical procedure?

Question 72

_{Post-operative management of patients w/ a pacemaker or ICD} How must a CIED (ICD or PM) that was programmed for the surgical procedure be managed post-op?

Answer 72

Continuous monitoring w/ both ECG and Pulse oximetry, and Consultation w/ the CIED physician/care team for device interrogation and restoration of appropriate settings If CIED is functionning properly and patient is stable, discharge to hospital ward or home, as appropriate Patient should resume usual CIED followup after discharge

Question 73

_{Post-operative management of patients w/ a pacemaker or ICD} How must a CIED (ICD or PM) that was _Not_ programmed for the surgical procedure be managed post-op if an EMI did occur during the procedure?

Answer 73

Continuous monitoring w/ both ECG and Pulse oximetry, and Consultation w/ the CIED physician/care team for device interrogation and restoration of appropriate settings If CIED is functionning properly and patient is stable, discharge to hospital ward or home, as appropriate Patient should resume usual CIED followup after discharge

Question 74

_{Post-operative management of patients w/ a pacemaker or ICD} How must a CIED (ICD or PM) that was **Not** programmed for the surgical procedure be _managed post-op_, if an EMI _did not_ occur during the procedure, but additional considerations such as "observed delivery of an ICD shock, or reasons to suspect CIED malfunction exist?

Answer 74

_Continuous monitoring_ w/ both **ECG** and **Pulse oximetry**, and Consultation w/ the CIED physician/care team for device **interrogation** and **restoration** of appropriate settings If CIED is functionning properly and patient is stable, discharge to hospital ward or home, as appropriate Patient should resume usual CIED followup after discharge

Question 75

_{Post-operative management of patients w/ a pacemaker or ICD} How must a CIED (ICD or PM) that was _Not programmed_ for the surgical procedure be **managed post-op**, if an _EMI did not occur_ during the procedure, and _No additional considerations_ such as "observed delivery of an ICD shock, or reasons to suspect CIED malfunction exist?

Answer 75

If CIED is functioning properly and patient is stable, discharge to the hospital ward or home, as appropriate Patient should resume usual CIED followup after discharge

Question 76

_{Perioperative mgnt of patients with Cardovascular Implantable Electronic Devices (CIED)} Important information to be given to the CIED team so they can provide specific recommendations to the surgical/procedural team regarding the preoperative preparation of the patient's CIED for the planned procedure

Answer 76

Intended surgical procedure Location of pulse generator Patient position during the procedure Type of electrocautery to be used Other sources of EMI likely to be present Whether cardioversion or defibrillation will be necessary Availability of Industry Employed Allied Health Professional or knowledgeable personnel with manufacturer-specific programmer Anticipated post-procedural disposition ^{(e.g. anticipated discharge to home <23 h, inpatient admission to critical care bed, telemetry bed)} Other circumstances ^{(cardiothoracic or chest wall surgical procedure that could impair/damage or encroach upon the CIED leads, anticipated large blood loss, operation in close proximity to CIED)}