Transcript ppt

Device Therapy in
Heart Failure
Teresa M. Menendez Hood, M.D., F.A.C.C.
Heart Failure
U.S.




Annual
Incidence
Heart Failure
Prevalence
Annual
Mortality
400,000
5.0 million
250,000
Up to 30 % of HF patients have an IVCD (80% with a
LBBB) which has been linked to increases in
mortality and morbidity.
HF is the leading cause of hospitalizations in the US
and uses up 5% of the health care costs
2% of the population and 6% of the population >65
Prevalence is on the rise.
Heart Failure Background
At Risk for Heart
Failure
Stage A
Heart Failure
Stage C
At high risk of HF but
Structural heart
without structural heart disease with prior or
disease or HF symptoms current HF symptoms
Stage B
Stage D
Structural heart disease Refractory HF
but without signs or
requiring specialized
symptoms of HF
interventions
NYHA Class-evaluates the disability
imposed on the patient who already has
structural heart disease
Class I
Class II
Class III
Asymptomatic
heart failure
ejection fraction
(EF) <40%
Mild symptomatic
heart failure
with ordinary
exertion
Moderate
symptomatic
heart failure
with less than
ordinary exertion
Class IV
Symptomatic
heart failure
at rest
Stages of Heart Failure
Leading Causes of Death in the
U.S.
Septicemia
You must combine
deaths from all cancers
to outnumber the deaths
from SCA each year.
Nephritis
Alzheimer’s Disease
Influenza/pneumonia
Diabetes
Accidents/injuries
Chronic lower respiratory diseases
Cerebrovascular disease
Other cardiac causes
Sudden cardiac arrest (SCA)
All other causes
All cancers
0%
5%
10%
15%
20%
25%
National Vital Statistics Report. Oct. 12, 2001;49(11).
MMWR. State-specific mortality from sudden cardiac death – US 1999. Feb 15, 2002;51:123-126.
SCD Rates in CHF Patients with LV
Dysfunction
Total Mortality
Sudden Death
Control Group Mortality
30
20
20
19
17
15
11
9
10
7
8
6
4
0
CHF-STAT
45 months
GESICA
13 months
SOLVD
V-HeFT I
41.4 months
27 months
SCD accounts for ~50% of the total deaths.
MERIT-HF
12 months
CIBIS-II
16 months
CARVEDILOL-US
6 months
SCD in Heart Failure
QRS
Duration
(msec)
Cumulative Survival
100%
<90
90%
90-120
80%
120-170
170-220
70%
>220
60%
0
60 120 180 240 300 360
Days
.
• QRS duration is an
independent predictor
of mortality (>140 ms)
• Other factors are:
age, creatinine, EF,
and HR
SCD in Heart Failure

Degree of SCD risk by class

Mortality in NYHA class II is 5 to 15%
 50

Mortality in NYHA class III is 20 to 50%
 Up

to 80% of the deaths are Sudden
to 50% of the deaths are Sudden
Mortality in NYHA class IV is 30 to 70%
5
to 30% of deaths are Sudden (more deaths from
pump failure)
Right Ventricular Pacing

RV apex pacing is harmful in patients
with LV dysfunction. Became evident
in multiple pacer and ICD trials that it
increases HF by producing a “paced”
LBBB.
 Abnormal
LV activation
 Reduced stroke volume
Detrimental RV pacing

MADIT II (2002) had a survival benefit
with the ICD but in a subgroup analysis,
there was an increase in heart failure
morbidity (more hospitalizations) felt
due to forced RV pacing compared to
controls in which no pacing was
present.
MADIT II: Complications
New or Worsening HF
19.9%
20.00%
14.9%
10.00%
0.00%
(p= 0.09)
Conventional Therapy
N= 490
ICD Therapy
•RV pacing causes ventricular
dysynchrony and may lead to
worsening HF.
• Intrinsic ventricular activation
is better for ICD patients with
left ventricular dysfunction
who do not “need” pacing.
•<10% of ICD patients have a
Class I pacing indication at the
time of implant…they do not
NEED pacing.
N= 742
•Physicians, when appropriate,
should consider programming
of ICDs to avoid frequent RV
pacing.
DAVID — Dual Chamber and VVI
Implantable Defibrillator Trial : 2002



ICD indication but
no indication for a
pacemaker
EF < 40%
DDDR @ 70BPM
versus VVI 40 BPM
Search AV Extension and Managed
Ventricular Pacing for Promoting
Atrioventricular Conduction (SAVE PACe)
Trial : 2007



1065 patients with sinus-node disease, intact AV
conduction and normal QRS interval
Randomized to conventional dual-chamber pacing
(n=535) or dual-chamber minimal ventricular pacing
(n=530)
― study tests new pacing algorithm that avoids
ventricular pacing except during periods of high-grade
AV block
With dual-chamber pacing, ↓ frequency RV pacing (9.1%
vs. 99%; p<0.001) and 40% relative risk ↓ in incidence of
persistent AF
The Concept



In most patients with an IVCD (QRS > 130
ms) , the presence of atrial-biventricular (RV
+ LV) pacing will provide early stimulation to
an otherwise late segment of electrical
activation in the LV.
This should translate into an increase in the
EF, decrease of the LV dimension,
improvement in the QOL and NYHA class.
This may translate into an decrease in CHF
exacerbations , hospitalizations and a
decrease in mortality.
The Proof

1994 –1997: Mechanistic and both short and
longer term observational studies. Studies
initially used epicardial leads placed by
thoracotomy or thorascope.


The first BiV pacer was implanted in 1994
1998 –1999: Randomized, controlled studies
to assess exercise capacity, functional status,
and quality of life.

There was development of transvenous leads via
the coronary sinus in to get to the LV.
Cohen TJ, Klein J. J Inva2002;14:48-53.
The Proof


2000 – 2006: Randomized, controlled trials to assess
combined mortality and CHF hospitalization. Also
evaluated the combined benefit of ICD’s with CRT.
2006-2008: Trials to identify patients who will benefit
from CRT. This uses echocardiographic markers of
dyssynchrony and the QRS measurement.


20% of patients do not respond to therapy in clinical trials
with a wide QRS and 50% patients with a narrow QRS/CHF
have dyssynchrony on echo and may benefit from this
therapy.
If the QRS is < 150 ms, then the chance of responding to
BiVP is ~5%. It will be in this patient group of QRS of 120150 ms where preselection of responders would be most
valuable.
The Cardiac
Resynchronization Clinical
Trials
PATH-CHF, MUSTIC, MIRACLE,
COMPANION, and CARE-HF*
*This is not a complete list of all the CRT trials and the dates given
are when the trial results were published.
Cumulative Patients
Cumulative Enrollment in Cardiac
Resynchronization Randomized
Trials
4000
CARE HF
MIRACLE ICD
3000
2000
1000
MIRACLE
MUSTIC AF
MIRACLE ICD II
MUSTIC SR
COMPANION
PATH CHF
PATH CHF II
CONTAK CD
0
1999
2000
2001
2002
2003
Results Presented
2004
2005
PATH-CHF: 1999
Pacing Therapy for Congestive Heart Failure




This was the first multicenter trial and
used the standard endocardial RV lead and
an epicardial LV lead via thoracotomy or
thorascope
Single blinded RCT
53 centers in Europe
41 patients
PATH-CHF

Primary endpoints



Secondary endpoints





Peak VO2
Six-minute walk distance
Minnesota Living with Heart Failure score (QOL)
NYHA class
EF
Trend towards decrease in Hospitalizations
Acute hemodynamic testing revealed that the
lateral and posterolateral walls were the best target
sites.

The best responders were those with QRS>150 , long PR
and dP/dt < 700 mm Hg/s
MUSTIC: 2001
Multicenter Stimulation in CM

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
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
European study with 67 patients
QRS>150, CHF, EF <35%
BiVP versus backup VVI pacing at 40 BPM
Increase in 6 minute walk time , QOL and Peak
VO2 with BiVP and persisted for up to 12
months
60% decrease in CHF hospitalizations
First to use endocardial LV leads via the CS
No significant change in mortality, but a trend
towards an improvement.
Acute hemodynamic studies showed the mid
lateral wall to be the best site
MIRACLE:2002
Multi-center In Sync Randomized Clinical
Evaluation Trial

Double blinded RCT
First US trial
Class 3 or 4, on OPT, QRS >130 ms, EF<35%

Enrollment of 453 patients


MIRACLE
NYHA class III-IV
LVEDD > 60 mm
QRS > 130 ms
Stable 3 month regimen of beta-blocker/ACE inhibitor
EF < 35%
Randomization
CRT on
CRT off
1- and 3-month follow-up
1- and 3-month follow-up
6-month follow-up
6-month follow-up
CRT on
Long-term follow-up
MIRACLE
Nonresponders: older, ischemic CM, no MR, QRS<150
Responders: had shorter duration on CHF and longer
QRS>155
P < 0.001
67%
Proportion
60%
40%
39%
34%
27%
20%
17%
16%
0%
Improved
Control N=225
No Change
Worsened
CRT N=228
MIRACLE

There was a decrease in hospitalizations of 50% at 6
months and a trend towards a decrease in mortality.

All other primary and secondary endpoints were met: 6
minute walk time, peak Vo2, QOL, EF , NYHA class,
LVEDD
Magnitude of improvement not influenced by degree of QRS
shortening with BiVP (average in all was –20msec)
FDA Approval
 The
first CRT device was
approved by the FDA in
September 2001 .
 The
first CRT with an ICD was
approved by the FDA in
May 2002 .
The Primary ICD Prevention Trials

MADIT 1 1996 required a positive EP
study;ischemics

MUSTT 1999 required a positive EP study;
ischemics; EF<40%

MADIT 2 2002 prior MI (ischemic cardiomyopathy)
and EF<30% (no EP study required) ;60% had CHF
and 50% had QRS > 120 ms; resulted in a 31%
decrease risk of death and halted prematurely due to
the positive effect of the ICD: resulted in the FDA
approving the ICD for primary prevention this patient
population, but only those with a QRS > 120 ms.
The Primary ICD Prevention Trials
 SCD-Heft
- 2005 The SCD-Heft trial
resulted in FDA approval of the ICD
January 2005 in patients with CHF and
EF<35 % that included both ischemic
and nonischemic cardiomyopathy for
primary prevention without a positive
EP study or ventricular ectopy . No
QRS cutoff was required.
COMPANION:2004
Comparison of Medical Therapy, Pacing
and
Defibrillation in Heart Failure
• OPT
Randomization
• OPT
• CRT
• OPT
• CRT-D
1
2
+
2
+
COMPANION





Enrolled 1520 patients class 3 and 4, QRS >120ms
Primary endpoint: death or hospitalization for any
cause
CRT met the primary endpoints and the CRT +/- ICD
significantly reduces mortality
This was the first to show mortality benefit from CRT
alone
Showed that patients with CRT also benefit from ICD
therapy

OPT had SCD in 36%, 23% in CRT and 3% in CRT+ICD
COMPANION
•
CRT arm had 20% reduction in mortality and
hospitalization over OPT arm but it was not
statistically significant
•
Significant reduction in CRT-ICD arm of 40% for
mortality over OPT arm (19% in OPT and 11% in
CRT-ICD group)
•
Study was halted prematurely due to its positive
benefit.
•
Mean follow up was 16 months
CARE-HFCArdiac
REsynchronization
in Heart Failure
2005





The effect of cardiac resynchronization on morbidity
and mortality in heart failure in 813 patients in
Europe ( prospective multicenter RCT) with
completed enrollment by 2002
Large patient size and length of trial (average follow
up of 29 months) allowed ability to asses effects of
CRT
Looked at CRT alone (no ICD)
Patients with class 3 or 4, EF < 35%, QRS >120 ms
There was a 37% reduced mortality or first
hospitalization for a cardiac cause compared to OPT
CARE-HF




All endpoints were met : EF, NYHA, QOL, BNP, Echo
and hemodynamic parameters
33% of the deaths in the CRT group were due to SCD
For every 9 devices, one death and 3 hospitalizations
were prevented
Echo criteria in patients with QRS 120-149ms to look for
dyssynchrony (had to have 2 of 3)…the “gray area
group”



Aortic pre-ejection delay of > 140 ms ( onset of QRS to Aortic
ejection)
Interventricular mechanical delay of >40 ms ( RV-LV)
Delayed activation of the postero-lateral LV wall (>50ms)
Primary Endpoint
(All-cause Mortality or Unplanned Hosp.
for Major CVS Event)
1.00
Event-free Survival
HR 0.63 (95% CI 0.51 to 0.77)
0.75
CRT : 159 pts (39%)
0.50
P < .0001
Medical : 224 pts
Therapy (55 %)
0.25
0.00
Number at risk
CRT
Medical
Therapy
0
409
404
500
323
292
273
232
1000
166
118
68
48
1500 Days
7
3
Conclusions


Conclusive results from CARE-HF demonstrate that CRT
should be considered as part of routine therapy for
patients with moderate to severe HF due to LVSD with
evidence (ECG supported by Echo) of cardiac
dyssynchrony to*:

Improve cardiac function and efficiency

Improve symptoms and QoL

Reduce morbidity

Prolong survival
These benefits are in addition to those of optimal
pharmacological therapy (OPT)
The
Resynchronization
Therapy in Normal
QRS (RethinQ) Study
2007
Background

Currently, indications for cardiac resynchronization therapy (CRT)
include QRS duration > 120ms, LVEF < 35% and NYHA
Class III-IV.

20-30% of patients do not respond to CRT despite application of
established selection criteria.

Patients with normal conduction or a slightly prolonged QRS
duration also exhibit mechanical abnormalities due to
intraventricular dyssynchrony.

Myocardial Tissue Doppler Imaging (TDI) allows both the velocity
and timing of regional longitudinal motion to be measured.

LV dyssynchrony may also be useful in predicting the benefit of
CRT before implantation of the pulse generator.
Hypothesis
We
hypothesized that patients with NYHA
class III, left ventricular ejection fraction
less than or equal to 35%, narrow QRS
duration < 130 ms, and evidence of
mechanical dyssynchrony on
echocardiography may benefit from cardiac
resynchronization therapy.
Echo Criteria for LV Dyssynchrony
Mechanical dyssynchrony considered present if either

M-Mode
- Septal posterior wall mechanical delay (SPWMD) ≥ 130
ms
OR

Tissue Doppler Imaging (TDI) of the basal ventricular
segments in apical 4/2/3 chamber views
- Septal to lateral delay ≥ 65ms
OR
- Antero-septal to posterior delay ≥ 65ms
Summary:RethinQ
 This
prospective, multi-center, randomized trial was
designed to evaluate the effectiveness of CRT therapy
in a HF population with narrow QRS duration and
evidence of mechanical dyssynchrony.
 There
was no statistical significant difference in the
change in Peak VO2 between the treatment and control
group during cardiopulmonary exercise testing.
 No
improvement in other objective parameters including
6-minute walk test, LV reverse remodeling, and
secondary endpoint - quality of life score .
Conclusion:RethinQ

CRT did not improve Peak VO2 during exercise in patients with
NYHA Class III heart failure, QRS duration <130ms, EF ≤ 35% and
mechanical dyssynchrony as specified in this trial.

While there was a statistically significant improvement of NYHA
class, a secondary endpoint, there was no improvement in qualityof-life, 6-minute walking test, or echocardiographic measures of
reverse LV remodeling
A subgroup of patients with QRS duration between
120 ms and 130 ms demonstrated an improvement from CRT,
however patients with QRS duration < 120 ms did not demonstrate
improvement


The subgroup of patients stratified on the basis of cardiomyopathy
etiology did not demonstrate an improvement in peak VO2.
PROSPECT TRIAL 5/2008






Predictors of response to CRT
53 centers worldwide, 426 patients
Patients had standard CRT indications (OMT, EF
< 35%, Class III-IV, QRS > 130)
12 ECHO parameters of dyssynchrony
69% of patients clinically improved and 56%
showed a decrease in LVESV of >15%
No single ECHO measure of dyssynchrony
could help select responders to CRT
BASE
Anterior
Posterior
APEX
RAO is best
to
distinguish
BASE
position
from
APEX
ANTERIOR
Anterior
LAO is best
to
distinguish
LATERAL
position
from
SEPTAL
S
E
P
T
A
L
Posterior
Lateral
INFERIOR
L
A
T
E
R
A
L
LAO
The 3 levels of Dyssynchrony
1.
2.
3.
Intraventricular dyssynchrony is best treated
by placing the LV lead in the best anatomic
location-usually the lateral or posterolateral
(proven my multiple studies). Get the LV
working.
Interventricular dyssynchrony is dealt with by
adjusting the V-V interval. Get the RV and the
LV to work together.
A-V dyssynchrony is dealt with by adjusting
the A-V interval. Get the atria and the
ventricles working together.
Posterolateral or Lateral walls are the best with
LBBB where the septum contracts first and then the
lateral wall last.
Paced at most
mechanically
delayed LV site
Paced at any
other LV site
0
10%
P=0.04
9%
-5
-9.2
Improvement
8%
-10
6%
-15
4%
-20
2%
2%
0%
Change in LVEF [%]
-25
-30
P=0.04
-28.4
Change in LV
End-systolic Volume [ml]
CRT and Tissue Doppler Imaging -a measure of
intraventricular delay
• Measures
dyssynchronous (delayed)
contraction patterns @
different areas of the
ventricle
•Measure from the onset
of the QRS to the peak
systolic shortening of that
segment
•Defined as a segment
with > 50 ms delay: this
indicates intraventricular
delay or asynchrony by
ECHO criteria
•Colors: greenyellow-red (the
longest delay of >300
ms)
V-V Timing: synchronize the RV
and the LV

The best V-V setting by measuring the RVOT and LVOT
via PW Doppler

V-V above > 40 ms is considered abnormal

In normals, the RV will contract before the LV in the
heart by -20 ms

LV and RV have different outputs in the newer devices
that allow sequential instead of simultaneous delivery
of output and thus allow for this to be programmable.
AV Delay Optimization Methods
1.
Electrocardiographic
 COMPANION
2.
trial method
Echocardiographic (combined)
 Aortic
velocity time integral (VTI) methods
 Mitral velocity Doppler methods:E and A waves
 Ritter formula
3.
Hemodynamic measurements
 Pulse
pressure method
 dP/dtmax method
Cardiac Resynchronization Therapy in Patients With
Severe Systolic Heart Failure:2008 Guidelines
I IIa IIb
IIbIII
III
I IIa IIb
IIbIII
III
I IIa IIb III
For patients who have left ventricular ejection fraction
(LVEF) less than or equal to 35%, a QRS duration greater
than or equal to 0.12 seconds, and sinus rhythm, cardiac
resynchronization therapy (CRT) with or without an ICD
is indicated for the treatment of New York Heart
Association (NYHA) functional Class III or ambulatory
Class IV heart failure symptoms on optimal
recommended medical therapy.
For patients who have LVEF less than or equal to 35%, a
QRS duration greater than or equal to 0.12 seconds, and
AF, CRT with or without an ICD is reasonable for the
treatment of NYHA functional Class III or ambulatory
Class IV heart failure symptoms on optimal
recommended medical therapy.
For patients with LVEF less than or equal to 35% with
NYHA functional Class III or ambulatory Class IV
symptoms who are receiving optimal recommended
medical therapy and who have frequent dependence on
ventricular pacing, CRT is reasonable.
Cardiac Resynchronization Therapy in Patients
With Severe Systolic Heart Failure : 2008
Guidelines
I IIa IIb III
I IIa IIb III
I IIa IIb III
For patients with LVEF less than or equal to 35% with
NYHA functional Class I or II symptoms who are receiving
optimal recommended medical therapy and who are
undergoing implantation of a permanent pacemaker
and/or ICD with anticipated frequent ventricular pacing,
CRT may be considered.
CRT is not indicated for asymptomatic patients with
reduced LVEF in the absence of other indications for
pacing.
CRT is not indicated for patients whose functional status
and life expectancy are limited predominantly by chronic
noncardiac conditions.
Indications for ICD Therapy
2008
Implantable CardioverterDefibrillators
I IIa IIb
IIbIII
III
ICD therapy is indicated in patients who are survivors of
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.
I IIa IIb III
ICD therapy is indicated in patients with structural heart
disease and spontaneous sustained VT, whether
hemodynamically stable or unstable.
I IIa IIb III
ICD therapy is indicated in patients with syncope of
undetermined origin with clinically relevant,
hemodynamically significant sustained VT or VF induced
at electrophysiological study.
All primary SCD prevention ICD recommendations apply only to patients who are receiving optimal medical therapy and have reasonable expectation of
survival with good functional capacity for more than 1 year.
Implantable CardioverterDefibrillators
I IIa IIb III
I IIa IIb III
ICD therapy is indicated in patients with LVEF less than or
equal to 35% due to prior MI who are at least 40 days
post-MI and are in NYHA functional Class II or III.
I IIa IIb III
ICD therapy is indicated in patients with nonischemic DCM
who have an LVEF less than or equal to 35% and who are
in NYHA functional Class II or III.
I IIa IIb
IIbIII
III
ICD therapy is indicated in patients with LV dysfunction
due to prior MI who are at least 40 days post-MI, have an
LVEF less than or equal to 30%, and are in NYHA
functional Class I.
I IIa IIb III
ICD therapy is indicated in patients with nonsustained VT
due to prior MI, LVEF less than or equal to 40%, and
inducible VF or sustained VT at electrophysiological study.
All primary SCD prevention ICD recommendations apply only to patients who are receiving optimal medical therapy and have reasonable expectation of
survival with good functional capacity for more than 1 year.
Implantable CardioverterDefibrillators
I IIaIIbIII
ICD implantation is reasonable for patients with unexplained
syncope, significant LV dysfunction, and nonischemic DCM.
I IIaIIbIII ICD implantation is reasonable for patients with sustained VT and
normal or near-normal ventricular function.
I IIaIIbIII ICD implantation is reasonable for patients with HCM who have 1
or more major† risk factors for SCD.
ICD implantation is reasonable for the prevention of SCD in
I IIaIIbIII patients with arrhythmogenic right ventricular
dysplasia/cardiomyopathy (ARVD/C) who have 1 or more risk
factors for SCD.
I IIaIIbIII ICD implantation is reasonable to reduce SCD in patients with longQT syndrome who are experiencing syncope and/or VT while
receiving beta blockers.
All primary SCD prevention ICD recommendations apply only to patients who are receiving optimal medical therapy and have reasonable expectation of
survival with good functional capacity for more than 1 year.
† See Section 3.2.4, “Hypertrophic Cardiomyopathy,” in the full-text guidelines for definition of major risk factors.
Implantable CardioverterDefibrillators
I IIaIIbIII
ICD implantation is reasonable for nonhospitalized
patients awaiting transplantation.
I IIaIIbIII
ICD implantation is reasonable for patients with Brugada
syndrome who have had syncope.
I IIaIIbIII
ICD implantation is reasonable for patients with Brugada
syndrome who have documented VT that has not resulted
in cardiac arrest.
I IIaIIbIII
ICD implantation is reasonable for patients with
catecholaminergic polymorphic VT who have syncope
and/or documented sustained VT while receiving beta
blockers.
I IIaIIbIII
ICD implantation is reasonable for patients with cardiac
sarcoidosis, giant cell myocarditis, or Chagas disease.
All primary SCD prevention ICD recommendations apply only to patients who are receiving optimal medical therapy and have reasonable expectation of
survival with good functional capacity for more than 1 year.
Implantable CardioverterDefibrillators
I IIaIIbIII
ICD therapy may be considered in patients with nonischemic
heart disease who have an LVEF of less than or equal to
35% and who are in NYHA functional Class I.
I IIa IIb
IIbIII
III
ICD therapy may be considered for patients with long-QT
syndrome and risk factors for SCD.
I IIaIIbIII
ICD therapy may be considered in patients with syncope
and advanced structural heart disease in whom thorough
invasive and noninvasive investigations have failed to define
a cause.
I IIaIIbIII
ICD therapy may be considered in patients with a familial
cardiomyopathy associated with sudden death.
I IIaIIbIII
ICD therapy may be considered in patients with LV
noncompaction.
All primary SCD prevention ICD recommendations apply only to patients who are receiving optimal medical therapy and have reasonable expectation of
survival with good functional capacity for more than 1 year.
Implantable CardioverterDefibrillators
I IIa IIb III
I IIa IIb III
ICD therapy is not indicated for patients who do not have
a 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, IIa, and IIb
recommendations above.
ICD therapy is not indicated for patients with incessant
VT or VF.
I IIa IIb III
ICD therapy is not indicated in patients with significant
psychiatric illnesses that may be aggravated by device
implantation or that may preclude systematic follow-up.
I IIa IIb III
ICD therapy is not indicated for NYHA Class IV patients
with drug-refractory congestive heart failure who are not
candidates for cardiac transplantation or cardiac
resynchronization therapy defibrillators (CRT-D).
All primary SCD prevention ICD recommendations apply only to patients who are receiving optimal medical therapy and have reasonable expectation of
survival with good functional capacity for more than 1 year.
Implantable CardioverterDefibrillators
I IIa IIb III
I IIa IIb III
I IIa IIb III
ICD therapy is not indicated for syncope of undetermined
cause in a patient without inducible ventricular
tachyarrhythmias and without structural heart disease.
ICD therapy is not indicated when VF or VT is amenable
to surgical or catheter ablation (e.g., atrial arrhythmias
associated with the Wolff-Parkinson-White syndrome, RV
or LV outflow tract VT, idiopathic VT, or fascicular VT in
the absence of structural heart disease).
ICD therapy is not indicated for patients with ventricular
tachyarrhythmias due to a completely reversible disorder
in the absence of structural heart disease (e.g., electrolyte
imbalance, drugs, or trauma).
All primary SCD prevention ICD recommendations apply only to patients who are receiving optimal medical therapy and have reasonable expectation of
survival with good functional capacity for more than 1 year.
Summary
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Large number of patients studied in multiple
RCTs.
CRT improves quality of life, exercise capacity,
functional capacity, EF, peak VO2.
CRT reduces the risk of mortality, worsening HF,
and hospitalizations for CHF.
CRT + ICD significantly reduces risk of mortality.