The document discusses implantable cardioverter defibrillators (ICDs), including: - ICDs protect against dangerous ventricular arrhythmias by delivering shocks or antitachycardia pacing. They contain pacemakers for bradycardia pacing. - ICD implantation indications include secondary prevention after cardiac arrest or unstable VT, and primary prevention for those with structural heart disease and reduced ejection fraction. - Potential complications include bleeding, infection, and inappropriate shocks. Patients require regular device checks and lifestyle restrictions like avoiding magnetic fields.

1. ICD
DR SEEBAT MASRUR
D-CARD STUDENT
CARDIOLOGY DEPARTMENT
SZMCH

2. Sudden Cardiac Death
Ref-https://www.aerjournal.com/articles/sudden-cardiac-death-and-arrhythmias
The accepted definition of SCD is death that
occurs within one hour of onset of symptoms in
witnessed cases, and within 24 hours of last
being seen alive when it is unwitnessed. The
majority of deaths are unwitnessed, with VF being
the final underlying mechanism. The majority of
patients are found in asystole or pulseless
electrical activity (PEA) and heart block is
increasingly noted as an aetiology.
An estimated 180,000–300,000 sudden cardiac
deaths (SCD) occur in the US annually. Worldwide,
sudden and unexpected cardiac death is the most
common cause of death,accounting for 17 million
deaths every year with SCD accounting for 25 %
of these.

4. An ICD is an electronic
device implanted in the
body to protect against
dangerous ventricular rates.
It is designed to defibrillate
the heart by delivering high
voltage shocks or to stop
malignant tachycardias by
antitachycardia pacing(short
burst of rapid pacing
sequence).Contemporary
ICDs also contain a classic
pacemaker for bradycardia
pacing.

5. Pioneers of ICDs-
M&M

6. Evolution of ICDs
▪ 1947- First Human internal Defibrillation
▪ 1956-First human external Defibrillation
▪ 1969-First external canine prototype tested
▪ 1970-First Implantable prototype
▪ 1975-First Implantable Defibin Canines
▪ 1980-First human implant @ Johns Hopkins
▪ 1985-ICD market released
▪ 1995-Pectoral ICD systems
▪ 2001-ICD & Resynchronization therapy

7. Evolution
With time the devices have grown smaller,
more efficient.

8. Components of ICD
1.Pulse Generator-Battery, Capacitors & Voltage
-Circuitry
-Connector Blocks
2.Lead System
3.ICD Programmer

9. Implantable Cardioverter Defibrillator

10. Types of ICD

11. Principles of Operation
▪ Bradycardia Pacing- Antitachycardia pacing
▪ Detection-Relies on rate sensing. When the rate of the sensed R waves falls into the
rate defined tachycardia zone, the detection algorithm is initiated and the counter is
augmented.
▪ Therapy- Antitachycardia Pacing, Cardioversion, Defibrillation.
▪ Electrogram Storage- All episodes are stored.
▪ Advanced features include rate-adaptive dual-chamber pacing, atrial therapies and
cardiac resynchronization therapy.

12. Uses of ICDs
Primary Prevention
▪ Prior Myocardial Infarction(at least 40
days ago) and LVEF ≤ 35%
▪ Cardiomyopathy, NYHA II to III with
LVEF < 35%
▪ Syncope who have structural heart
disease and inducible VT/VF
▪ Long QT, Torsades on RX, Brugada,
ARVD, HCM
Secondary Prevention
▪ Prior episode of resuscitated VT/VF or
sustained hemodynamically unstable VT
▪ Episodes of spontaneous sustained VT in
the presence of Heart Disease(valvular,
ischemic, hypertrophic, dilated or
infiltrative cardiomyopathies) and other
settings(eg channelopathies)

13. Class I (general agreement of benefit with ICD
therapy)
Ref-Cardiology 3rd ED Micheal H Crawford
▪ Cardiac arrest due to ventricular fibrillation or hemodynamically unstable sustained VT after
evaluation to define the cause of the event and to exclude any completely reversible causes.
▪ Structural heart disease and spontaneous sustained VT, whether hemodynamically stable or
unstable.
▪ Syncope of undetermined origin with clinically relevant, hemodynamically significant sustained
VT or VF induced at electrophysiological study.
▪ LVEF less than 35% due to prior MI, at least 40 days post-MI with NYHA functional Class II or III.
▪ Nonischemic dilated cardiomyopathy (DCM) with an LVEF less than or equal to 35% and NYHA
functional Class II or III.
▪ LV dysfunction due to prior MI, at least 40 days post-MI with an LVEF less than 30%, and NYHA
functional Class I.
▪ Nonsustained VT due to prior MI, LVEF less than 40%, and inducible VF or sustained VT at
electrophysiological study

14. Class II (ICD therapy reasonable or may be considered)
Ref- Ref-Cardiology 3rd ED Micheal H Crawford
▪ Unexplained syncope, significant LV dysfunction, and nonischemic DCM.
▪ Sustained VT and normal or near-normal ventricular function.
▪ HCM with 1 or more major risk factors for SCD.
▪ Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and 1 or more
risk factors for SCD.
▪ Long-QT syndrome with syncope and/or VT while receiving beta blockers.
▪ Miscellaneous high risk conditions including Brugada syndrome, catecholaminergic
polymorphic VT, Chagas’ disease, cardiac sarcoidosis, giant cell myocarditis, left
ventricular noncompaction, and other familial cardiomyopathies associated with
sudden death.

15. Class III (not indicated; risk of ICD therapy exceeds
expected benefit)-Contraindications
▪ No reasonable expectation of survival with an acceptable functional status for at least
1 year, even if they meet ICD implantation criteria specified in the Class I and II
recommendations above.
▪ Incessant VT or VF.
▪ Significant psychiatric illnesses that may be aggravated by device implantation or that
may preclude systematic follow-up.
▪ NYHA Class IV drug-refractory congestive heart failure when cardiac transplantation or
cardiac resynchronization therapy are not indicated

16. Types
Ref-https://www.jacc.org/doi/10.1016/j.jacc.2015.11.026
An ICD is a type of cardiac therapy device. There are two basic types:
▪ A Traditional ICD-is implanted in the chest and the wires(Leads) attach to the
heart. The implant procedure requires invasive surgery.
▪ A Subcutaneous ICD(S-ICD) is another option that`s implanted under the
skin at the side of the chest below the armpit. It`s attached to an electrode
that runs along the breastbone. An S-ICD is larger than traditional ICD but
doesn`t attach to the heart.

17. Ref-
https://www.jacc.org/doi/10.1016/j.jacc
.2015.11.026

18. Procedure

19. Complications
Venous access
▪ Bleeding
▪ Pain
▪ Hemoptysis
▪ Pneumothorax
▪ Subcutaneous emphysema
▪ Thoracic duct injury
▪ Subclavian vein Thrombosis
▪ Subclavian artery puncture , fistula
▪ Pulmonary embolism
▪ Air embolism
▪ Brachial plecus injury
Pocket
▪ Hematoma
▪ Skin erosion
▪ Infection
▪ Seroma

20. Complications
Leads
▪ Malposition
▪ Dislodgement
▪ Perforation
▪ Exit Block without displacement
▪ Intracardiac Thrombosis
▪ Infection
▪ Hemopericardium
▪ Cardiac tamponade
▪ Post Pericardiotomy Syndrome
▪ Diaphragmatic Stimulation
Lead Electrical problems
▪ Insulator Break
▪ Conductor Break
▪ Lead disconnection
▪ Loose setscrew
▪ Connection problems
▪ Inadequate defibrillation threshold
▪ undersensing

21. Complications
Inappropriate delivery of therapy
▪ Inappropriate shocks most often occur
due to supraventricular tachycardia (and
sinus tachycardia), self-terminating VT (in
committed systems), and sensing
artifacts, for example myopotentials. T-
wave oversensing is an uncommon cause
of inappropriate shocks
Failure to deliver therapy or delay of
therapy
▪ ICD inactivation
▪ Ventricular tachycardia slower than
the programmed detection rate
▪ SVT–VT discriminators

22. ICD-INDUCED
PROARRHYTHMIAS

23. POSTOPERATIVE EVALUATION AND CARE
▪ Ward Care-staff members are familiar with the basic programmed parameters.
▪ Emergency Care-During an emergency, however, care of the patient must be based
on basic and advanced cardiac life support protocols, and standard emergency
treatment is not delayed.
▪ Device Monitoring
▪ Operation Site-A final assessment of the implant site, pacing thresholds, EGM
amplitude and programmed parameters may be done by a physician or other allied
health professional prior to patient discharge.
▪ Noninvasive Electrophysiology Study-A NIPS is performed using the device and
programmer to initiate and terminate arrhythmias.
▪ Patient Education-Physical activity, wound care, pain management, and what to do
should an ICD shock occur.

25. Movement restriction

26. Outpatient follow-up and ICD device checks
There are two types of clinical follow-up for patients:
1.Chronic surveillance every 3–6 months to assess and document routine
device operation and clinical progress. First follow up within a month.
2.A cute unexpected evaluations prompted by patient concerns, symptoms,
shocks, unsuccessful therapy or presumed failure to deliver expected
therapy.
When the ICD battery starts to show signs of depletion, evaluations need to
be more frequent. Sound or audible alarms may be programmed to alert the
patient when the battery voltage becomes critically low. The patient should
be instructed to notify their physician if an alert sounds.

28. Living with an ICD
Take the following precautions when you have an ICD implanted.
▪ Always carry an ID card that states you have an ICD.
▪ If you travel by air, tell security screeners that you have an ICD before
going through the metal detector.
▪ Anti-theft systems or electronic article surveillance (EAS) used in
department stores may interact with an ICD.
▪ Stay away from large magnetic fields such as power generation sites.
▪ If an MRI has been advised for you, contact your doctor. Newer ICDs are
compatible with MRI scanners with some restrictions.

29. Living with an ICD
▪ Don't use diathermy. This is the use of heat in physical therapy to treat
muscles. Don't use a heating pad directly over your ICD.
▪ Don't have transcutaneous electrical nerve stimulation (TENS) therapy.
▪ Stay away from high-voltage and radar machinery.
▪ If you are scheduled for surgery, let the surgeon know well ahead of the
operation that you have an ICD. Also talk with your cardiologist before
the procedure to find out if you need any special safety measures.
▪ Always see your doctor when you feel ill after an activity, or when you
have questions about beginning a new activity.

30. Thank you

31. How you prepare

32. General Instruction
The doctor’s office should be notified if any of the following signs are observed,
especially if they increase after the first days:
▪ 1. Any redness, heat, swelling or any kind of yellow, green or brown drainage
from the site.
▪ 2. A soreness around the pulse generator or a bruise that does not go away.
▪ 3. A temperature of or above 100°F (38°C) or chills. The patient should
check his or her temperature at home twice daily at the same time for 2
weeks and write it down on a piece of paper.

33. Patients Instruction at time of Discharge
Prior to discharge, a final check is performed to verify proper functioning of
the ICD system so as to:
• ensure that the device is activated;
• perform final device programming;
• document lead position by chest X-ray and measure pacing threshold and R-
wave amplitude to rule out early lead dislodgment;
• provide patient and family education;
• plan outpatient follow-up: 7 days and 1 month after implantation.

34. Contraindications
Contraindications The ICD is contraindicated if there is a transient reversible
cause, such as
▪ Myocardial infarction
▪ Electrolyte Imbalance
▪ Incessant ventricular tachycardia or fibrillation is also considered a
contraindication(as incessant arrhythmias will cause frequent device
therapy and rapid battery drainage)
▪ Psychiatric illnesses