Download Sudden Cardiac Death in Heart Failure

Sudden Cardiac Death in
Heart Failure
Dr David Sim
Associate Consultant
Heart Failure/Transplant
National Heart Centre Singapore
Introduction
Ventricular
arrhythmias common in HF
– Malignant or potentially lethal arrhythmias
(VT/VF)
– Non sustained or hemodynamically tolerated
arrhythmias (NSVT, VPB, AIVR)
Clinical significance largely based upon whether
they predict future malignant arrhythmias or SCD
Causes of Death in HF
Exact percentages vary with severity of disease
– Progressive pump failure
– Unexpected SCD
– SCD during episodes of clinical worsening of HF
VT degenerating into VF most common cause of
SCD
Other causes of SCD
– Bradyarrhythmias
– Non arrhythmic
Causes of death in HF
70
64
59
60
56
50
40
33
30
24
20
10
12
26
15
11
0
NYHA II
NYHA III
NYHA IV
Effect of metoprolol CR/XL in chronic heart failure: Metoprolol CR/XL Randomised
Intervention Trial in Congestive Heart Failure (MERIT-HF)
Lancet 1999 Jun 12;353(9169):2001-7.
CHF
Other
SCD
Primary Prevention
Role
of ICD
– Severity of LV dysfunction
– Severity of clinical HF
– Etiology of LV dysfunction (ischemic or non
ischemic)
Risk
of SCD increases with severity of both
LV dysfunction and clinical HF
Predictors of SCD
Ischemic
– Signal averaged ECG
– Heart rate variability
– Twave alterans
Non ischemic
– Risk stratificvation more difficult
– Only LVEF significantly associated with arrhythmia
risk
Marburg Cardiomyopathy Study (Grimm W, Christ M, Bach J et al. Circulation 2003;
108:2883.
ACC/AHA 2009 Guidelines
Primary Prevention
Clinical Trials of Primary
Prevention
MUSTT
–
Buxton AE, Lee KL, Fisher JD et al. N Engl J Med 1999; 341:1882.
MADIT/MADIT
–
–
II
Moss, AJ, Hall, WJ, Cannom, DS, et al. N Engl J Med 1996; 335:1933.
Moss AJ, Zareba W, Hall WJ et al. N Engl J Med 2002; 346: 877-83.
DINAMIT
–
Hohnloser SH, Kuck KH, Dorian P et al. N Engl J Med. 2004; 351:2481.
SCD
–
HeFT (ischemic/non ischemic)
Bardy, GH, Lee, KL, Mark, DB, et al. N Engl J Med 2005; 352:225.
DEFINITE
–
(non ischemic)
Kadish A, Schaechter A, Subacius H et al. J Am Coll Cardiol. 2006; 47: 2477.
EPS guided therapy
MADIT
MUSTT
– N= 196
– NYHA I-III
– Prior MI,
– N= 704
– NYHA I-III
– Prior MI,
asymptomatic NSVT,
LVEF 35% or less,
inducible sustained VT
on EPS
– ICD vs
pharmacological
therapy
asymptomatic NSVT,
LVEF 40% or less,
inducible sustained VT
– No therapy vs EPS
guided antiarrhythmic
therapy (antiarrhythmic
agent or ICD)
EPS guided therapy
MADIT II
N
= 1232
MI > 30 days (> 3 months if bypass surgery
performed)
LVEF 30% or less
ICD vs conventionl medical therapy
SCD-HeFT
N=
2521
NYHA II/III
Ischemic or non ischemic
LVEF 35% or less
3 arms
– ICD
– Amiodarone
– Placebo
Quality of Life
Prognostic significance of ICD
shocks
Timing of ICD implantation
DINAMIT
N=
674
Post MI within the preceding 6 to 40 days
LVEF 35% or less
Reduced HR variability or elevated resting
HR (80 beats/min or more)
Timing of ICD implantation
Cardiac Resynchronization
Therapy
Development
of ventricular dyssynchrony
in some patients with HF and
cardiomyopathy
Ventricular dyssynchrony refers to the loss
of coordinated contraction across the LV,
which can further impair the pump function
of the failing ventricle, resulting in worse
HF symptoms
CXR : biventricular pacing
ACC/AHA 2009 Guidelines
CRT
Companion trial
N=
1520
NYHA III/IV
LVEF 35% or less
QRS duration of at least 120ms
Hospitalization for HF in preceding 12
months
Bristow MR, Saxon LA, Boehmer J et al. N Engl J Med. 2004 May 20;350(21):2140-50.
Bristow MR, Saxon LA, Boehmer J et al. NEJM 2004; 350: 2140
Antiarrhythmic drugs
RCTs
do not support the routine use of
prophylactic antiarrhythmic drugs, other
than beta blockers, to prevent SCD in
patients with HF.
Lack of benefit
– Proarrhythmia
– Incomplete suppression of ventricular
arrhythmias
Amiodarone
Advantae
of relatively low rate of
proarrhythmia
Not recommended for prevention of SCD
Decrease recurrence of
– Atrial arrhythmias
– ICD discharge for ventricular arrhythmias
Beta-Blockers
(CIBIS II) Lancet 1999 Jan 2;353(9146):9-13.
(MERIT-HF) Lancet 1999 Jun 12;353(9169):2001-7.
Secondary Prevention
High
risk of future arrhythmic events and
SCD in patients with HF
– Survive an episode of SCD
– Sustained VT
ICD
: most effective for improving survival
ACC/AHA 2009 Guidelines
Secondary Prevention
Meta-analysis
Other treatment options
Antiarrhythmic drugs
– Adjunct to ICD in patients with frequent shcoks
– Patients who refused ICD or are not candidate for ICD
Radiofrequency abalation
– Bundle branch reentrant VT
Arrhythmia Surgery
Cardiac Transplantation
– Need ICD as bridge to Transplant
Low Rate of Automated Defibrillator Implantation in
Heart Failure Patients
Dr Choon Pin Lim, RN Lee Wah Teo, Dr Chi Keong Ching, Dr Bernard Wing Kuin Kwok, Dr David Kheng Leng Sim
National Heart Centre SINGAPORE
Background
Internal cardioverter-defibrillator (ICD) has been shown to prevent sudden cardiac deaths in patients with left ventricular ejection fraction (LVEF) <35%. We report on the
prevalence of AICD implantation in heart failure (HF) patients receiving contemporary treatment at our centre.
Method
A single centre retrospective study over a 6 months period including patients < 80 years old, who were enrolled in our heart failure clinical care pathway was performed.
Demographics including gender, age, LVEF and HF aetiology were analysed. The prevalence of ICD implantation in patients enrolled in our formal heart failure programme
(HFP) was compared with those followed up in the general cardiology clinic.
Results
Of the 321 patients, 59.5% had an LVEF of less than 35%. Of these 191 patients, 75.9% were male, 24.1% female. Mean age was 62.6±10.6 years. Mean LVEF was
21.6±6.4%. The most common aetiologies were ischaemic heart disease (69.6%) and non-ischaemic dilated cardiomyopathy (17.3%). 38 patients did not fulfill standard
indications for ICD implantation (including LVEF improvement > 35% during follow-up, recent or planned coronary revascularization, poor premorbid condition and/or
NYHA IV functional status). Of the 153 patients who had standard indications for ICD, only 21.6% received an ICD during the course of 6 months follow-up. 17.6% (n=27)
of these eligible patients were enrolled in a HFP: 51.9% received an ICD, 37.0% declined ICD implantation, while 11.1% were not offered. Majority (n=126) were followed
up in the general cardiology clinic: 15.1% received an ICD implantation, 19.0% declined ICD implantation, while 65.9% were not offered. The main reason for patients
declining ICD implantation was financial constraints.
Ischaemic
Cardiomyopathy
69.6%
Non-ischaemic Dilated
Cardiomyopathy
17.3%
Alocoholic
Cardiomyopathy
4.2%
Rheumatic Heart
Disease
3.1%
5.8%
Others
0
10
20
30
40
50
60
70
Heart Failure Aetiology
11.1%
37.0%
51.9%
Heart Failure Programme patients
15.1%
65.9%
19.0%
AICD implanted
Delined AICD
AICD not offered
General Cardiology Clinic patients
Conclusions
The prevalence of ICD implantation in HF patients was 21.6% in our study, with a higher rate amongst patients who were enrolled in a HFP. This may be attributable to the
lack of awareness amongst general cardiologists and the high cost of device implantation locally.
Demographic
191
(59.5%) out of 321 patients had LVEF
≤ 35%
Male (75.9%) and female (24.1%)
Chinese (64.9%), Malay (21.5%), Indian
(13.1%), Other (0.5%)
Mean Age : 62.6 ± 10.6 (youngest 29,
oldest 79)
Mean LVEF 21.6%
Eligibility for ICD
38
patients did not fulfil standard
indications for ICD
–
–
–
–
LVEF improve
Planned coronary revascularization
Poor premorbid condition
NYHA IV
153 patients fulfil criteria for
– 126 General cardiology clinic
– 27 Heart Failure Clinic
ICD
Results
70
65.9
60
51.9
50
AICD implanted
37
40
30
20
Declined AICD
Not offered
19
15.1
11.1
10
0
General
HF
Conclusions
Optimal medical therapy + lifestyle modification
in all patients
Device therapy in selected patients
Low rate of usage of AICD in local context
Strategies warranted to increase the awareness
among physicians to adhere to the recommended
guidelines