Indications of ICD in 2010

Dr Mervat AboulmaatyProfessor of CardiologyAin Shams University

DAF 1st EP course 2010

SCD Burden

SCD Risk

ICDImplantable Cardiovertor Defibrillator

• First human implants• Thoracotomy, multiple incisions• Primary implanter= cardiac surgeon• General anesthesia• Long hospital stays• Complications from major surgery• Perioperative mortality up to 9%• Nonprogrammable therapy• High-energy shock only• Device longevity 1.5 years• Fewer than 1,000 implants/year

1980:Large Devices, Limited Battery Life, Abdominal Implant, Epicardial Leads

• First-line therapy for VT/VF patients• Treatment of atrial arrhythmias• Cardiac resynchronization therapy for HF• Transvenous, single incision• Local anesthesia; conscious sedation• Short hospital stays and few

complications• Perioperative mortality < 1%• Programmable therapy options• Single- or dual-chamber therapy• Battery longevity up to 9 years*• More than 100,000 implants/year

Today:Small Devices, Long Battery Life, Pectoral Implant, Endocardial Leads

*Battery longevity information in slide notes.

Atrium & Ventricle

• Bradycardia sensing & Pacing

Atrium AT/AF tachyarrhythmia

detection Antitachycardia pacing Cardioversion

Ventricle VT/ VF detection Antitachycardia pacing Cardioversion Defibrillation

Therapies Provided by Today’sDual-Chamber ICDs

CRT-DMultisite ICD

Indications for ICDs

• Primary– Prevent a SCD event before it occurs

• Define patients at risk

• Secondary– Prevent SCD event after an initial event survival

• Exclude transient or reversible causes for VF

MADIT 1996

(196 patients)

* Mild HF”:NYHA Class I and II ; High-risk”:EF ≤30%; QRS ≥130ms

MADIT II 2002

(1232 patients)

MADIT-CRT 2005

(1820 patients)

Clinical Question: Can prophylactic ICD therapy improve survival in high risk HF patients when compared to medical therapy alone?

Endpoint: All-cause mortality.

Key Finding: Use of ICDs resulted in a 54% reduction in the mortality rate in the ICD group as compared to the conventional medical therapy group (p value: 0.009)

Clinical Question: Can heart attack survivors with impaired heart function (EF≤30%), and no other risk stratification, benefit from ICD therapy versus conventional therapy alone?

Endpoint: All-cause mortality.

Key Finding: Use of ICDs resulted in a 31% reduction in the risk of death in heart attack survivors (p value: 0.016). As a result , patients no longer have to undergo invasive electrophysiological testing to receive the ICD therapy

Clinical Question:Does early intervention with CRT-D slow the progression of HF in high-risk patients* with mild HF* when compared to ICD-only therapy?

Endpoint: All-cause mortality OR first HF event.

Key finding: CRT-D therapy is associated with a significant 34% reduction in death or first HF event when compared to ICD therapy alone (p value: 0.001)

1 Moss AJ. N Engl J Med. 1996;335:1933-40.2 Buxton AE. N Engl J Med. 1999;341:1882-90.3 Moss AJ. N Engl J Med. 2002;346:877-834 Moss AJ. Presented before ACC 51st Annual Scientific Sessions,

Late Breaking Clinical Trials, March 19, 2002.5 The AVID Investigators. N Engl J Med. 1997;337:1576-83.6 Kuck K. Circ. 2000;102:748-54.7 Connolly S. Circ. 2000:101:1297-1302.

ICD mortality reductions in primary prevention trialsare equal to or greaterthan those in secondaryprevention trials.

1 3, 42

5 76

Reductions in Mortality with ICD Therapy

54%

75%

55%

76%

31%

61%

27 months 39 months 20 months

31%

56%

28%

59%

20%

33%

% M

orta

lity

Red

uctio

n w

/ IC

D R

x%

Mor

talit

y R

educ

tion

w/ I

CD

Rx

3 Years 3 Years 3 Years

Class I

• Documented survivors of SCD due to VF• 40days post MI + LVEF≤ 35 + NYHA II/III• 40 days post MI + LVEF≤ 30 + NYHA I• Non ischemic cardiomyopathy + LVEF≤ 35 + NYHA

II/III• Non sustained VT post MI + sustained VT/VF by

EPS+ LVEF ≤ 40• Structural heart disease + sustained VT• Syncope + unstable VT/VF by EPS

Class IIA

• LQTS + syncope/VT (on β blockers)• Unexplained syncope + DCM + significant LV

dysfunction• Sustained VT + normal LV• CPVT + syncope/VT (on β blockers)• High risk ARVD• High risk HCM• Brugada syndrome + syncope/VT

Indications for ICD in HF patients

Guidelines of ICD in a Pocket

Indications for ICD implantationClass III

ICD is NOT indicated IN

• Syncope of undetermined cause no VT induced NO structural HD

• Incessant VT VF• VT/VF resulting from arrhythmias amenable

for ablation as WPW Fasicular VT• VT due to reversible disorder• Significant psychological disorder• Terminal illness life expectancy <6months

55 yr old, first hour of Acute MI

ICDs are reliable devices that have the potential to add

quality years of life for appropriate candidates.

There are scientifically-derived guidelines for their

prescription that are limited by the scope of the clinical trials

and observational data.

Cardiologists should recommend ICD devices to their

individual patients based on the current guidelines.

Conclusions

ICD Programming

ZoneRate

(bpm)

Cycle Length

(ms)

No. of Beats to Detect Therapies

VF > 250 <240 18 of 24 30 J × 6

FVT 201-250 299-240 18 Burst (1), 30 J × 6

VT < 150-200 400-300 16 Burst (2), ramp (1), 20 J, 30 J × 3

How ICD works?

I C D I N T E R R O G A T I O N

VT Burst 1 Sinus

I C D I N T E R R O G A T I O N

Burst Acc. VTVT

I C D I N T E R R O G A T I O N

DC SinusAcc.VT

Cont.

I C D I N T E R R O G A T I O N

Thank you