Guia riesgo y manejo de muerte subita

1. Circulation Journal
Official Journal of the Japanese Circulation Society
JCS GUIDELINES
http://www. j-circ.or.jp
Guidelines for Risks and Prevention of Sudden
Cardiac Death (JCS 2010)
– Digest Version –
JCS Joint Working Group
Table of Contents
Introduction to the Revised Guidelines················ 489 7. Dilated Cardiomyopathy············································ 495
I
Prediction of Sudden Death 8. Arrhythmogenic Rght Ventricular Cardiomyopathy···· 495 ·
and Examinations···················································· 490 9. Other Myocardial Disorders······································ 495
·
10. Brugada Syndrome··················································· 495
1. Clinical Findings························································ 490
11. Congenital Long QT Syndrome· ······························· 496
·
2. Electrocardiogram····················································· 490
12. Wolff-Parkinson-White Syndrome····························· 497
3. Heart Rate Variability················································ 490
·
13. Catecholamine-Induced Polymorphic Ventricular
4. Heart Rate Turbulence·············································· 490
Tachycardia······························································· 497
5. Baroreflex Sensitivity················································· 490
14. Other Arrhythmias····················································· 497
6. T-Wave Alternans· ···················································· 490
·
15. Valvular Heart Disease· ············································ 498
·
7. Late Potential···························································· 490
·
8. Cardiac Electrophysiological Study··························· 490 III
Prevention of Sudden Death in Children············ 498
9. Exercise Stress Test················································· 491
· 1. Sudden Infant Death Syndrome································ 498
10. Genetic Tests···························································· 491 2. Arrhythmias······························································· 499
II
Prevention of Sudden Death· ································· 491 3. Commotio Cordis· ····················································· 500
·
4. Congenital Heart Diseases······································· 501
·
1. Arrhythmias······························································· 491
5. Pediatric Hypertrophic Cardiomyopathy· ·················· 501
·
2. Cardiogenic Syncope················································ 492
6. Kawasaki Disease····················································· 502
3. Heart Failure······························································ 492
4. Ischemic Heart Diseases· ········································· 493
· References···································································· 502
5. Hypertrophic Cardiomyopathy··································· 494
6. Other Heart Diseases Associated With Cardiac
Hypertrophy······························································· 494 (Circ J 2012; 76: 489 – 507)
Introduction to the Revised Guidelines
The best way to prevent sudden death is predicting the occur- fatal tachycardia. Severe bradycardia and asystole, which also
rence of sudden death and providing appropriate preventive may cause sudden death, are described in the present guide-
measures. Since many cases of sudden death are arrhythmic lines as needed in relation to pathological conditions and dis-
death, the present guidelines describe disease conditions and eases known to lead to bradycardia and asystole. The present
typical clinical findings that may cause arrhythmic death and guidelines is partly revised and reflect the newest findings to
how to prevent sudden deaths in patients with such predicted be included to the guidelines for the non-pharmacological and
findings. Since ventricular tachyarrhythmias (VTA) including pharmacological treatment of arrhythmia of which the Japa-
ventricular fibrillation (VF) play an important role in the devel- nese Circulation Society (JCS) are currently revising.
opment of arrhythmic death, and the benefits of implantable The present guidelines are written mainly for the use of
cardioverter defibrillator (ICD) in preventing sudden death due cardiologists since pathological conditions and diseases that
to tachycardia have been demonstrated, the present guidelines may cause arrhythmic death must be carefully assessed by
mainly discuss the use of ICD in the treatment of potentially expert cardiologists, and since ICD therapy, the most impor-
Released online January 12, 2012
Mailing address: Scientific Committee of the Japanese Circulation Society, 8th Floor CUBE OIKE Bldg., 599 Bano-cho, Karasuma
Aneyakoji, Nakagyo-ku, Kyoto 604-8172, Japan. E-mail: meeting@j-circ.or.jp
This English language document is a revised digest version of Guidelines for Risks and Prevention of Sudden Cardiac Death reported at the
Japanese Circulation Society Joint Working Groups performed in 2009. (website: http://www.j-circ.or.jp/guideline/pdf/JCS2010aizawa.
d.pdf)
Joint Working Groups: The Japanese Circulation Society, The Japanese Coronary Association, The Japanese Association for Thoracic Surgery,
Japanese Society of Pediatric Cardiology and Cardiac Surgery, Japanese Association of Cardiovascular Intervention and Therapeutics, The
Japanese Society for Cardiovascular Surgery, Japanese College of Cardiology, The Japanese Society of Electrocardiology, The Japanese
Heart Failure Society, Japanese Heart Rhythm Society
ISSN-1346-9843 doi: 0.1253/circj.CJ-88-0022
1
All rights are reserved to the Japanese Circulation Society. For permissions, please e-mail: cj@j-circ.or.jp
Circulation Journal Vol.76, February 2012

2. 490 JCS Joint Working Group
tant method to prevent such conditions, is performed by car- are also essential for resuscitated patients. We hope that the
diologists. Since most arrhythmic deaths occur as a result of present guidelines will help emergency medicine specialists
an out-of-hospital cardiac event, it is needless to say that suc- and practitioners in the front lines who see patients with car-
cess or failure of resuscitation is extremely important, and diovascular diseases.
appropriate measures to prevent recurrence of cardiac events
I Prediction of Sudden Death and Examinations
There are laboratory examinations that are believed to be use-
ful in identifying those patients at a high risk for sudden death, 3. Heart Rate Variability
especially arrhythmic death. The majority of these examina-
tions assess electrical activity of the heart and the activity of Class IIa
the autonomic nervous system. Clinical symptoms of cardiac • rediction of sudden death in patients after myocardial
P
dysfunction and heart failure are also important findings to infarction (MI)8
identify patients at a high risk for sudden death. Although Class IIb
patients at a risk for sudden death can be identified (predicted) • rediction of sudden death in patients with cardiomyopa-
P
with these examinations, only a few of these examinations thy9,10
have been demonstrated to be useful in terms of primary pre-
vention of sudden death in clinical research. The current use-
fulness of clinical findings and laboratory examinations in 4. Heart Rate Turbulence
terms of predicting sudden death is listed by the class of rec-
ommendation, although there is some controversy as to the Class IIb
validity of methods used in the evaluation of predictive factors • rediction of sudden death in patients after MI and patients
P
for arrhythmia and sudden death. with heart failure11
Classification of Recommendations
Class I: Conditions for which there is general agreement 5. Baroreflex Sensitivity
that a given clinical finding/laboratory examina-
tion is useful in predicting sudden death Class I
Class IIa: Conditions for which there is some divergence of • rediction of sudden death in patients with cardiac dys-
P
opinion, but weight of opinion is in favor of use- function after MI12
fulness
Class IIb: Conditions for which there is some divergence of
opinion, but weight of opinion is against useful- 6. T-Wave Alternans
ness
Class III: Conditions for which there is general agreement Class IIa
that the clinical finding/laboratory examination is • rediction of cardiac sudden death in patients after MI and
P
not useful in predicting sudden death in patients who have ischemic cardiomyopathy with car-
diac dysfunction13
Class III clinical findings/laboratory examinations are not Class IIb
described in this document as a rule. • rediction of cardiac sudden death in patients with (non-
P
ischemic) dilated cardiomyopathy (DCM) or heart fail-
ure14,15
1. Clinical Findings
Class I 7. Late Potential
• decrease in ejection fraction (≤30 to 35%) in patients
A
with ischemic and non-ischemic heart failure1–3 Class IIb
• rediction of sudden death in patients after MI16
P
2. Electrocardiogram
8. Cardiac Electrophysiological Study
Class I
• valuation of ventricular arrhythmia with standard 12-
E Class I
lead electrocardiogram (ECG) • atients after MI who have palpitation, near syncope or
P
Class IIb syncope suspected to be caused by VTA
• valuation of patients with heart failure, cardiac hypertro-
E • valuation of patients following catheter ablation for the
E
phy (hypertrophic cardiomyopathy [HCM], hypertension, treatment of ventricular tachycardia (VT)
and aortic stenosis), and arrhythmogenic right ventricular • atients with syncope of unknown cause who have cardiac
P
cardiomyopathy (ARVC) based on QT dispersion (QTD)4–6 dysfunction, organic heart disease, a family history of sud-
• valuation of patients with syncope associated with long
E den death and/or abnormal ECG findings
QT syndrome (LQTS) or HCM according to the magni- Class IIa
tude of transmural dispersion of repolarization (TDR)7 • atients after MI who have nonsustained ventricular
P
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3. JCS Guidelines for Risks and Prevention of Sudden Cardiac Death 491
tachycardia (NSVT) and a left ventricular ejection fraction rhythmia
(LVEF) of ≤40%17 Class IIb
• atients with syncopes that are suspected to be caused by
P • atients with ventricular arrhythmia who are unlikely to
P
bradycardia or tachyarrhythmia but not confirmed with have coronary diseases
non-invasive examinations • valuation of premature ventricular contraction (PVC) in
E
patients in middle-age or older
9. Exercise Stress Test
10. Genetic Tests
Class I
• xercise induced VTA in patient suspected to have coro-
E Class IIa
nary disease • ardiac ion channel gene mutations (LQTS mutations, es-
C
• atients who have or are suspected to have exercise
P pecially LQT1, LQT2 and LQT3 mutations) and site of
induced ventricular arrhythmia mutation19,20
• bnormal blood pressure reactions in patients with HCM18
A Class IIb
Class IIa • bnormalities of the genes of ryanodine receptor (RyR2)
A
• valuation of the efficacy of drug treatment or catheter
E or calsequestrin (CASQ) 2 in catecholamine-induced poly-
ablation in patients with exercise induced ventricular ar- morphic ventricular tachycardia (CPVT)21
II Prevention of Sudden Death
This section lists major pathological conditions and diseases Class III measures are not described in this guideline.
that are known to precede sudden death, and describes rela- For example, in this guideline, ICD therapy and antiarrhyth-
tionship between these conditions and arrhythmic death. This mic drugs are listed as Class I measures, but this does not
section also describes typical signs/symptoms and laboratory mean that ICD therapy and antiarrhythmic drugs are similarly
findings of the pathological conditions/diseases believed to effective in the prevention of sudden death. This means that
cause sudden death as possible predictive factors and lists there is evidence or consensus that Class I measures decrease
measures to prevent the patient at a high risk for sudden car- the incidence of arrhythmic death as compared with control
diac death as either primary or secondary prevention of ar- groups. Limitation of exercise is a Class I measure to prevent
rhythmic death. exercise induced arrhythmia. Measures listed in the same class
Types and indications of preventive measures are listed by do not necessarily target the same goal of treatment. Physi-
the class of recommendation. cians should be aware of this to select appropriate measures
for individual patients.
Classification of Recommendations
Class I: Conditions for which there is general agreement
that a given measure is indicated 1. Arrhythmias
Class IIa: Conditions for which there is some divergence of
opinion, but weight of opinion is in favor of the 1. Cardiac Arrest (Resuscitated Cases)
use of a given measure Sustained ventricular tachycardia (SVT) and VF are the most
Class IIb: Conditions for which there is some divergence of frequent causes of cardiac arrest. Cardiac arrest recurs fre-
opinion, but weight of opinion is against the use quently and the risk of sudden death is extremely high. ICD
of a given measure therapy is the most effective secondary preventive measure for
Class III: Conditions for which there is general agreement sudden death.22–24
that the measure is not useful
Table 1. Prevention of Sudden Death in Patients With Sustained Ventricular Tachycardia or Ventricular
Fibrillation
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• ardiac arrest (VF)
C ICD Amiodarone* or sotalol*
• atients with SVT who have syncope during tachycardia, or
P ICD Amiodarone* or sotalol*
patients with LVEF 40% with a low blood pressure (80 mmHg)
• atients with hemodynamically stable SVT with underlying heart
P ICD Amiodarone* or sotalol*
disease in whom drugs are not effective or contraindicated
• atients with underlying heart disease and in whom SVT is no
P ICD
longer induced after catheter ablation Amiodarone* or sotalol*
• atients with SVT associated with underlying heart disease and
P ICD + effective drugs
a LVEF of ≥40% who are responding to drug treatment
*Use to control VT/VF episodes in patients contraindicated for ICD therapy or patients already undergoing ICD therapy.
ICD, implantable cardioverter defibrillator; LVEF, left ventricular ejection fraction; SVT, sustained ventricular tachy-
cardia; VF, ventricular fibrillation; VT, ventricular tachycardia.
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4. 492 JCS Joint Working Group
Table 2. Prevention of Sudden Death in Patients With Cardiogenic Syncope (Syncope Other Than Those
Caused by Non-Cardiac Causes)
Findings Class I Class IIa Class IIb
• atients in whom unstable SVT or VF is induced, and drug effi-
P ICD
cacy cannot be assessed
• atients with underlying heart disease in whom hemodynamically
P ICD
stable SVT is induced and drug treatment and catheter ablation
are ineffective
• atients with underlying heart disease and cardiac dysfunction in
P ICD
whom hemodynamically unstable SVT or VF is induced and drug
efficacy has not been assessed
• atients with dilated or hypertrophic cardiomyopathy in whom
P ICD
hemodynamically unstable SVT or VF is not induced
• atients with a history of asystole associated with sick sinus
P Pacemaker
syndrome or atrioventricular block
Note) efer to the Guidelines for Non-Pharmacological Therapy of Cardiac Arrhythmias22 reported by the Japanese
R
Circulation Society for the management of patients with bradycardia. The management of primary arrhythmia
is described in a later section.
ICD, implantable cardioverter defibrillator; SVT, sustained ventricular tachycardia; VF, ventricular fibrillation.
2. Sustained Ventricular Tachycardia 1. resence of cardiac disorders that may cause transient
P
In Japan, the underlying disease of SVT is old MI in about 30%, asystole
and non-ischemic heart disease in the majority of patients.22,25 2. VT or VF induced during electrophysiological study
S
SVT is treated mainly with procaineamide and lidocaine.26,27 (EPS)
Amiodarone and nifekalant are recommended for patients 3. uspected to have unstable SVT in a patient with a his-
S
with refractory SVT.27 Patients with a history of high-rate, tory of stable SVT
hemodynamic deterioration of SVT require measures to pre- 4. resence of cardiomyopathy without SVT or VF induced
P
vent recurrence, and should be considered for the indication during EPS
for ICD therapy first. Since patients with hemodynamically 5. resence of primary arrhythmic disorder
P
stable SVT associated with organic heart disease may often 6. resence of sinus node dysfunction or atrioventricular
P
experience high-rate episodes or new onset of VT with differ- block
ent waveforms, their prognoses are not good and ICD therapy Treatment strategies to prevent arrhythmic deaths mainly
is thus recommended for them.28 Patients following successful consist of ICD therapy. See the sections of Brugada syndrome
catheter ablation for the treatment of SVT are often indicated and LQTS for the prevention of arrhythmic death in patients
for ICD therapy since their long-term prognosis is unclear and with these diseases.
recurrent SVT is occasionally observed (Table 1).
3. Premature Ventricular Contraction and 3. Heart Failure
Nonsustained Ventricular Tachycardia
When no heart diseases are present, the prognosis of individu- The mortality of patients with heart failure is higher in patients
als with PVC and NSVT is good, and these arrhythmias do not with more severe disease by New York Heart Association
represent risk factors for sudden death. Whether primary pre- (NYHA) classification.36 In recent large-scale clinical studies
vention of sudden death is indicated for patients with PVC or of patients with heart failure, sudden cardiac death developed
NSVT depends on the type of underlying diseases, which are in 9 to 22% of the patients.37–41 The percentage of sudden
described in the following sections. death cases among all-cause death cases is higher in patients
with milder heart failure (NYHA Class I or II) than in severer
4. Bradycardia patients (NYHA Class III or IV). The most likely causes of
Bradycardia accounts for about 10% of all deaths due to sudden cardiac death among patients with heart failure are
arrhythmia.29,30 Bradycardia gradually leading to asystole has SVT and VF.42
been observed in patients with arrhythmic death.30 The most About half of patients with out-of-hospital cardiac arrest
common causes of bradycardia leading to arrhythmic death are (resuscitated) or patients with SVT (in Japan) are considered
sick sinus syndrome and atrioventricular block, which require to have cardiac dysfunction.43–47 Patients with proven VF or
treatment with a pacemaker.31–33 The pacemaker treatment of SVT should undergo secondary preventive treatment mainly
these conditions is described in the Guidelines for Non-Phar- using an ICD.
macological Therapy of Cardiac Arrhythmias reported by the In patients after MI, cardiac dysfunction is an independent
JCS.22 predictive factor of poor prognosis. ICD therapy has been
demonstrated to be useful as a primary preventive measure for
sudden death in patients with cardiac dysfunction after MI.1
2. Cardiogenic Syncope (Table 2) ICD therapy has also been demonstrated to be useful in the
primary prevention of sudden death in patients with DCM.2,3
Cardiogenic syncope is defined as syncope other than those due Although a number of studies have reported that amioda-
to non-cardiac causes such as orthostatic syncope and syncopes rone decreases the incidence of sudden death, some studies
due to vasovagal reflex and seizures.34,35 Cardiogenic syncope have denied such effect. β-blockers improve the prognosis and
due to arrhythmia may be identified with the following condi- decrease the incidence of sudden death in patients with chronic
tions: heart failure.41,48 Angiotensin converting enzyme (ACE) in­
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5. JCS Guidelines for Risks and Prevention of Sudden Cardiac Death 493
Table 3. Prevention of Sudden Death in Patients After Myocardial Infarction
Clinical findings Class I Class IIa Class IIb
Secondary prevention
• atients with a history of SVT, VF or resuscitated cardiac
P ICD Amiodarone, sotalol,
arrest catheter ablation
Primary prevention
• atients with syncope (+), NSVT (+) and LVEF 40% in whom
P ICD
SVT or VF is induced and drug treatment is ineffective
• atients with syncope (–), NSVT (+) and LVEF 35% in whom
P ICD
SVT or VF is induced and drug treatment is ineffective or drug
efficacy has not been assessed
• atients with cardiac dysfunction (LVEF 35%)
P β-blockers, ACE ICD
inhibitors, anti-
aldosterone drugs
Note) rug treatment is generally believed to improve the prognosis, but no consensus has been achieved. The
D
significance of drug treatment is not identical to those of ICD and catheter ablation.
ACE, angiotensin converting enzyme; ICD, implantable cardioverter defibrillator; LVEF, left ventricular ejection frac-
tion; NSVT, nonsustained ventricular tachycardia; SVT, sustained ventricular tachycardia; VF, ventricular fibrillation.
Table 4. Prevention of Sudden Death in Patients With Variant Angina
Purpose of treatment/findings Class I Class IIa Class IIb
Primary/secondary prevention
• resence of SVT or VF during anginal attack
P Calcium channel blockers Nitrates, nicorandil ICD
ICD, implantable cardioverter defibrillator; SVT, sustained ventricular tachycardia; VF, ventricular fibrillation.
hibitors have also been demonstrated to decrease all-cause ods are sudden death as a result of out-of-hospital cardiac
mortality and sudden deaths in this patient population.49 In arrest. Patients at a high risk of sudden death after MI are
patients with severe heart failure, aldosterone antagonists de- identified on the basis of cardiac function and the presence of
creased the incidence of sudden death.50 Cardiac resynchroni- ventricular arrhythmia. Patients with post-MI VT/VF are
zation therapy with defibrillator (CRT-D) is currently per- mainly treated with ICD therapy for secondary prevention of
formed for patients with heart failure who are indicated for sudden death.
ICD therapy.51 It has been demonstrated that ICD therapy as primary pre-
vention of post-MI sudden death improves the prognosis of
patients who have cardiac dysfunction (LVEF 40%), NSVT
4. Ischemic Heart Diseases and SVT induced during EPS,46 and patients with severe car-
diac dysfunction (LVEF 30%) (Table 3).1–3
Known risk factors for sudden death in patients with coronary Amiodarone is used to prevent arrhythmic death in patients
heart disease include elderly, male sex, a history of syncope after MI,39,40 but some studies have denied the preventive ef-
and a family history of sudden cardiac death. However, treat- fects in this patient population.3 β-blockers and spironolactone
ment to prevent sudden death is not initiated because of the are effective in decreasing sudden death in post-MI patients
presence of such risk factors only. with heart failure. Catheter ablation may be effective in con-
trolling monomorphic VT, when VT is no longer induced by
1. Acute Myocardial Infarction programmed electrical stimulation. However, since many
Acute myocardial infarction (AMI) is the most common acute post-MI patients have polymorphic SVT or cannot undergo
condition leading to fatal arrhythmia. VF often develops in electrophysiological mapping, patients often have to receive
patients with AMI, especially those in a very early phase of other treatment methods in addition to catheter ablation.
the disease. Secondary VF may develop in association with In Europe and the United States, supplementation of poly-
cardiogenic shock and pump failure. unsaturated fatty acids is recommended to prevent sudden
VF in patients with AMI may be effectively controlled with death.56 Since the number of stenotic lesions, the results of
ECG monitoring and electrical defibrillation. Defibrillation by reperfusion therapy during AMI, and the patency of the artery
emergency medical service and treatment with an automated responsible for MI after treatment affect the incidence of
external defibrillator (AED) are expected effective for patients arrhythmic accidents, it is important to improve myocardial
with out-of-hospital VF. The Guidelines for Management of ischemia including asymptomatic myocardial ischemia as much
Acute Coronary Syndrome without Persistent ST Segment as possible.
Elevation reported by the JCS describe how to treat VT/VF
and atrioventricular block to prevent sudden death in patients 3. Variant Angina
with AMI.52 Patients with variant angina may experience angina attacks
leading to fatal ventricular arrhythmia.57,58 Patients with vari-
2. Post-Myocardial Infarction ant angina often die from sudden death, which is believed to
The one-year mortality of patients after MI was as high as be associated with multi-vessel coronary spasm. The progno-
10 to 20%, and especially 6-month mortality after onset is sis of patients with variant angina associated with VT is poor.
the highest.53–55 Most of the death cases during these peri- Patients with a history of coronary spastic attacks should be
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6. 494 JCS Joint Working Group
Table 5. Prevention of Sudden Death in Patients With Hypertrophic Cardiomyopathy
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• atients with cardiac arrest, SVT or VF
P ICD Amiodarone
Limitation of exercise
Primary prevention
• atients with more than one risk factor*
P Limitation of exercise ICD, amiodarone
• atients with one risk factor*
P Limitation of exercise Amiodarone ICD
*Recurrent syncopal attacks, a family history of sudden death, presence of severe left ventricular wall thickening
(≥30 mm) or an insufficient increase in blood pressure during exercise (≤20 mmHg).
Note) requent (≥5 times/day) or multiple repetitive runs of NSVT (at least 10 beats).
F
ICD, implantable cardioverter defibrillator; NSVT, nonsustained ventricular tachycardia; SVT, sustained ventricular
tachycardia; VF, ventricular fibrillation.
Table 6. Prevention of Sudden Death in Patients With Dilated Cardiomyopathy
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• atients with SVT or VF
P ICD Aldosterone Amiodarone
ACE inhibitors/ antagonists
β-blockers
Primary prevention
• atients with syncope (+), LVEF ≤40% in whom SVT or
P ICD Amiodarone
VF is induced, and drug treatment is ineffective
• atients with syncope (–), LVEF ≤40% in whom SVT or
P ICD, Amiodarone
VF is induced, and drug treatment is ineffective aldosterone
antagonists
• atients with syncope (+), LVEF ≤40% in whom SVT or
P ICD,
VF is induced, and drug efficacy has not been assessed amiodarone
• atients with LVEF ≤36% and NSVT or frequent PVC
P ICD
(≥10 times/hr)*
• atients with LVEF ≤30% and NSVT
P Amiodarone
*According to the DEFINITE study.
ACE, angiotensin converting enzyme; DEFINITE, DEFibrillators In Non-Ischemic Cardiomyopathy Treatment Evalua-
tion; ICD, implantable cardioverter defibrillator; LVEF, left ventricular ejection fraction; NSVT, nonsustained ventricular
tachycardia; PVC, premature ventricular contraction; SVT, sustained ventricular tachycardia; VF, ventricular fibrillation.
treated with calcium channel blockers to prevent recurrence of (5) decrease or insufficient increase (≤20 mmHg) in sys-
A
attacks. ICD therapy may be considered for patients who still tolic blood pressure during exercise stress test18,59,70
have coronary spastic attacks after treatment with sufficient The indication for primary prevention of sudden death should
doses of calcium channel blockers and have severe ventricular be determined according to the presence of above risk factors
arrhythmia, but it is unclear whether ICD therapy may improve (Table 5). In the Guidelines for Diagnosis and Treatment of
the vital prognosis of these patients (Table 4). Patients with Hypertrophic Cardiomyopathy reported by the
JCS,71 primary prevention is indicated according to whether
VT/VF is induced during EPS.
5. Hypertrophic Cardiomyopathy
The annual mortality of patients with HCM has been reported 6. Other Heart Diseases Associated
as 1 to 2%.59–63 Although HCM does not necessarily represent With Cardiac Hypertrophy
a poor prognosis, more than half of death cases among patients
with HCM are sudden death. HCM is an important cause of Left ventricular hypertrophy is observed in patients with hyper-
sudden death especially in young patients. Patients resusci- tension, those with aortic stenosis and those with athlete’s heart.
tated from cardiac arrest and patients with SVT are at high risk The incidences of cardiovascular accidents such as sudden
for sudden death, and are indicated for ICD therapy as second- death, arrhythmia, heart failure, MI and stroke are higher in
ary prevention. individuals with left ventricular hypertrophy than those without
Risk factors for sudden death in patients with HCM it.72–74 It is unclear that left ventricular hypertrophy per se
include: increases the risk for sudden death or not, while the incidence
(1) ecurrent syncopal attacks (especially syncopes occur-
R of sudden death is considered to be high among patients with
ring in children during exercise)61,63,64 left ventricular hypertrophy complicated with arrhythmia,75–78
(2) first-degree family history of sudden death or multiple
A coronary artery disease79,80 or heart failure.81,82
family history of sudden death61,64,65 Secondary prevention of sudden death with ICD therapy is
(3) omplication with NSVT66–68
C indicated for patients with left ventricular hypertrophy associ-
(4) ignificant left ventricular wall thickening (maximum
S ated with SVT or VF, but the results of primary prevention
thickness ≥30 mm)69 have not been reported.
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7. JCS Guidelines for Risks and Prevention of Sudden Cardiac Death 495
Table 7. Prevention of Sudden Death in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• atients with cardiac arrest or VF
P ICD
Primary prevention
• atients in whom SVT is induced, having a family history of
P ICD Amiodarone, sotalol
sudden death or LP-positive patients with right heart failure
ICD, implantable cardioverter defibrillator; LP, late potential on the signal averaged body surface electrocardiogram;
SVT, sustained ventricular tachycardia; VF, ventricular fibrillation.
Table 8. Prevention of Sudden Death in Patients With Brugada Syndrome
Purpose of treatment Class I Class IIa Class IIb
Secondary prevention
• atients in whom cardiac arrest or VF/TdP is confirmed
P ICD
Primary prevention
• atients who meet at least 2 criteria of (1) a history of syncope (2) a family
P ICD
history of sudden death and (3) VF is induced during electrophysiological study
• atients who meet one of the above 3 criteria
P ICD
ICD, implantable cardioverter defibrillator; TdP, torsades de pointes; VF, ventricular fibrillation.
tients with extensive abnormal right ventricular wall motion,
7. Dilated Cardiomyopathy those with VT induced during EPS, and those affecting the
right and left ventricles.95,96 Monomorphic VT is commonly
Major causes of death of patients with DCM are heart failure induced and catheter ablation is often successful, but long-
(about 50%) and sudden death (30 to 40%).83,84 Many cases of term outcome of catheter ablation remains unknown. ICD
sudden death are caused by VT or VF, but severe bradycardia therapy is the first-choice secondary preventive method. Dur-
may lead to sudden death.38 Patients with a history of SVT or ing a 3-year follow-up of patients undergoing ICD therapy,
VF are indicated for secondary prevention using an ICD. ICD was activated in about half of the patients.
Some patients with monomorphic SVT may be successfully In the primary prevention, the indication for ICD therapy
treated with catheter ablation. should be determined according to the presence/absence of
A multivariate analysis of the prognosis of patients with SVT induced during EPS with lesions of larger size and a fam-
DCM has revealed that a history of SVT or VF and LVEF are ily history of sudden death (Table 7).
risk factors for sudden death in this patient population.85 The
incidence of arrhythmic accidents is high among patients
with NSVT and a LVEF of 30%.86 In the analysis of DCM 9. Other Myocardial Disorders
patients implanted with an ICD, the incidence of arrhythmia
is high among those with low LVEF (≤30%). It has been dem- SVT and VF may develop as a complication of cardiac sar-
onstrated that ICD therapy is effective as primary prevention coidosis, muscular dystrophy, chronic lung disease, progres-
of sudden death in patients with a LVEF of ≤36% associated sive systemic sclerosis or diabetes mellitus, and so on.97 It is
with either NSVT or frequent PVC.2 difficult to predict occurrence of sudden death, SVT or VF in
All-cause mortality and incidence of sudden death are high these patients. When the presence of these conditions is con-
among patients with DCM complicated with left bundle firmed or strongly suspected, the use of an ICD should be
branch block. Currently, the types and indications of primary considered.
prevention of sudden death among patients with DCM are
determined according to the symptoms, cardiac function, pres-
ence/absence of SVT and VF induced during EPS, and so on 10. Brugada Syndrome
(Table 6).22
Brugada syndrome is a disorder characterized by right bundle
branch block pattern with ST segment elevation in V1 to V3
8. Arrhythmogenic Right Ventricular leads on ECG, and may cause sudden death mainly due to VF
Cardiomyopathy at night.98,99 Brugada syndrome is considered to be consistent
with sudden unexpected nocturnal death syndrome in South-
ARVC is a disease with unknown cause that is characterized east Asia and “Pokkuri disease” in Japan. History of VF or
with fatty infiltration in the right ventricle (often extending to syncope represents a significant risk factor for sudden death in
the left ventricle) and VT originated from the right ventri- patient with Brugada syndrome, and ICD therapy is indicated
cle.87–89 Patients with ARVC start to show right heart failure for such patients. It has been reported that quinidine is effec-
in their 40 to 50 s. In Europe and the United States, ARVC tive in preventing arrhythmic attacks and activations of the
should be suspected in cases of sudden death or cardiac arrest ICD in patients with Brugada syndrome.100–103
in patients under 35 years old.69,90–93 In Japan, ARVC is the The need of primary prevention including ICD therapy is
underlying disease of SVT in about 10% of patients.22,94 usually determined in each institution on the basis of ECG
The incidence of arrhythmic accidents is high among pa- findings and presence/absence of VF induced during EPS, and
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8. 496 JCS Joint Working Group
Table 9. Prevention of Sudden Death in Patients With Congenital Long QT Syndrome
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• atients with VF or cardiac arrest
P ICD
Primary prevention
• atients meeting ≥2 of the 3 criteria of (1) a history of TdP or syncope,
P ICD
(2) a family history of sudden death, (3) not responding to β-blockers
• atients responding to β-blockers with a history of TdP or syncope or
P β-blockers ICD
a family history of sudden death
ICD, implantable cardioverter defibrillator; TdP, torsades de pointes; VF, ventricular fibrillation.
Table 10. Indications of Drug Treatment in Patients With Congenital Long QT Syndrome
Purpose of treatment/findings Class I Class IIa Class IIb
• atients with a history of syncope (especially those with LQT1 or LQT2
P β-blockers
mutation)
• symptomatic patients with QT prolongation, congenital deafness, being
A β-blockers
neonates/infants, having a family history of sudden death of siblings, and
anxiety for sudden death or strong desire for treatment by patients or
their family
• symptomatic patients without congenital deafness, or a family history of
A Mexiletine β-blockers
sudden death of siblings, and who either have LQT3 mutation with a
history of syncope or have LQTS not responding to monotherapy with β-
blockers
Note) xercise and drugs prolonging QT interval (antiarrhythmic drugs, tricyclic antidepressants and antihistamines)
E
are contraindicated in all patients.
LQTS, long QT syndrome.
Table 11. Prevention of Sudden Death in Patients With WPW Syndrome
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• atients with VF, cardiac arrest or syncope
P Catheter
ablation
Primary prevention
• atients with a R-R interval during atrial fibrillation of ≤250 msec
P Catheter Amiodarone, Class
ablation Ia and Ic drugs
• atients with a refractory period of antegrade conduction over the
P Catheter
accessory pathway of ≤270 msec, patients with multiple accessory ablation
pathways, patients with a family history of sudden death or athletes
VF, ventricular fibrillation; WPW, Wolff-Parkinson-White.
so on (Table 8).104 thereafter, the incidence of cardiac accidents is higher in
female than male patients. Cardiac accidents during childhood
are more common in boys than girls with LQT1 mutation, but
11. Congenital Long QT Syndrome there are no sex differences among patients with LQT2 and
LQT3 mutations.109 The incidence of cardiac event (eg, syn-
The congenital LQTS is a group of genetic arrhythmic disor- cope, cardiac arrest or sudden death) by the age of 40 years
ders that cause syncope and sudden death due to ventricular was 63%, 46% and 18% in patients with LQT1 (n=112),
arrhythmia characterized by QT prolongation and torsades LQT2 (n=72) and LQT3 (n=62) mutations, respectively, and
de pointes (TdP), and include Romano-Ward syndrome and the mortality was 4% in patients with LQT1 and LQT2 muta-
Jervell and Lange-Nielsen syndrome.105–108 Since cardiac ar- tions and as high as 20% in patients with LQT3 mutation.109
rest is the first manifestation of the congenital LQTS in 10% Congenital LQTS patients with a history of cardiac arrest are
of patients, it is quite important to predict and prevent cardiac indicated for ICD therapy combined with β-blockers and lim-
arrest. To date, 12 different genetic mutations (referred to as itation of exercise (Tables 9,10).
LQT1 through LQT12) have been reported to be related to The risk of occurrence of TdP is high among patients with
congenital LQTS. The prevalence is highest for LQT1, which LQT2 mutation and a QTc of 500 msec and male patients
is followed by LQT2 and LQT3. Patients with LQT1, LQT2 with LQT3 mutation.109 Patients with recurrent syncopes
and LQT3 account for most of the patients with congenital despite treatment with β-blockers,112 and patients with a family
LQTS.109,110 history of sudden death are at a high risk for cardiac events.113
In male patients, arrhythmic accidents often occur before TdP often develops during exercise, and especially swimming,
adolescence, and the incidence of arrhythmic accidents is among patients with LQT1 mutation; in association with men-
higher in male than female patients.111 During adolescence and tal stress, sudden auditory stimuli or immediately after child-
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9. JCS Guidelines for Risks and Prevention of Sudden Cardiac Death 497
Table 12. Prevention of Sudden Death in Patients With Catecholamine-Induced Polymorphic Ventricular
Tachycardia
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• atients with VF or cardiac arrest
P ICD
+ β-blockers
+ Calcium channel blockers
+ Flecainide
Primary prevention
• yncope
S ICD, left stellectomy
• ale patients with RyR2 mutation or patients
M β-blockers ICD
with CASQ2 mutation + Calcium channel blockers
+ Flecainide
• hildren with a family history of sudden death,
C β-blockers
NSVT or syncope
Note) xercise should be limited in all patients.
E
CASQ2, calsequestrin 2 gene; ICD, implantable cardioverter defibrillator; NSVT, nonsustained ventricular tachycar-
dia; RyR2, ryanodine receptor; VF, ventricular fibrillation.
birth among those with LQT2 mutation; and during sleep is no sex difference in incidence. In patients with CPVT, exer-
among those with LQT3 mutation.110,114 In patients with LQT2 cise and intravenous isoproterenol induce a gradual increase
mutation, the risk of occurrence of TdP is high among patients in PVC, which further lead to polymorphic or bidirectional
with mutations in the pore region of the human-ether-related VT, very fast polymorphic VT (350 to 400/min), and finally to
gene (HERG gene).20,115 Primary prevention consists of limita- VF. Recently, genetic mutations of RyR221,128–136 and CASQ2
tion of exercise and treatment with β-blockers. Mexiletine is genes137,138 have been found in patients with CPVT.
effective for patients with LQT3 mutation, and pacing is used Secondary prevention is indicated for patients in whom VF
for patients with bradycardia. or polymorphic VT was observed. The use of an ICD as pri-
mary prevention is indicated for patients with a family history
of sudden death or a history of syncope. Pharmacological pre-
12. Wolff-Parkinson-White Syndrome ventive treatment mainly consists of β-blockers. When treat-
ment with β-blockers is insufficient, calcium channel blockers
It has been reported that symptomatic Wolff-Parkinson-White such as verapamil may be effective in some cases.139,140 In
(WPW) syndrome is observed in 1 to 2/1,000 individuals, the addition to these drugs, strict limitation of exercise is impor-
incidence of sudden death is 0.02 to 0.15%/year, and the inci- tant. Male patients with RyR2 mutation and patients with
dence of VF is about 3 to 4 fold of the incidence of sudden CASQ2 gene mutation need early implantation of an ICD
death.116 Even in patients with asymptomatic WPW syndrome, (Table 12).132
VF may develop in rare cases during the first episode of atrial
fibrillation. WPW syndrome may usually be completely treated
with catheter ablation,22,117 and the risk of sudden death will 14. Other Arrhythmias
disappear after treatment (Table 11).
The incidence of VF tends to be higher in young male 1.
Non-Brugada Type Idiopathic Ventricular
patients.118,119 The risk of VF is high among patients with a Fibrillation
history of atrial fibrillation or reciprocating tachycardia. It has Some cases of idiopathic VF do not represent ECG findings
been reported that about half of patients experience VF during characteristic to Brugada syndrome.141,142 It is important to dif-
the first episode of atrial fibrillation.118 It is believed that VF ferentiate non-Brugada type idiopathic VF from Brugada syn-
develops in 20 to 40% of patients with multiple Kent bun- drome of which characteristic ECG findings may vary and be
dles.119 The presence of Ebstein’s anomaly is considered a risk normalized over time. Cases of polymorphic VT initiated in
factor for sudden death in patients with WPW syndrome. the Purkinje’s fiber have been recently reported, and are suc-
On the other hand, the risk of sudden death is considered cessfully treated with catheter ablation.143 There is a condition
low in patients with intermittent WPW syndrome and patients called variant Brugada syndrome characterized by idiopathic
in whom delta waves disappear after intravenous administra- VF characterized with Brugada syndrome-like ST segment
tion of ajmaline or procainamide.120,121 Patients at a high risk elevation in leads II, III and aVF.
of transition from atrial fibrillation to VF may be identified on
the basis of the refractory period of antegrade conduction over 2.
Polymorphic Ventricular Tachycardia Triggered by
the accessory pathway or the shortest R-R interval during Short-Coupled Ventricular Premature Contraction
atrial fibrillation induced during EPS.118,122,123 This condition develops as very short-coupled PVC (≤250 msec
in many cases), which leads polymorphic VT to VF.144
13. Catecholamine-Induced Polymorphic 3. Polymorphic Ventricular Tachycardia Resulting
Ventricular Tachycardia From Ventricular Parasystole
There are cases of polymorphic VT originating from a ven-
The first episodes of CPVT often manifest during childhood tricular parasystolic rhythm.145 If it is transient, polymorphic
after infancy as exercise induced polymorphic VT or VF.124–127 VT terminates without causing further changes, while if it
CPVT is not associated with organic heart diseases, and there persists, it may lead to VF.
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10. 498 JCS Joint Working Group
Table 13. Prevention of Sudden Death in Patients With Aortic Stenosis
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• VT or VF
S ICD
Surgical repair of stenotic valves
Primary prevention
• atients with ventricular arrhythmia in whom SVT
P Surgical repair of stenotic valves Amiodarone
or VF is induced
• atients with severe valvular stenosis
P Surgical repair of stenotic valves
ICD, implantable cardioverter defibrillator; SVT, sustained ventricular tachycardia; VF, ventricular fibrillation.
Table 14. Prevention of Sudden Death in Patients With Mitral Valve Prolapse
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• VT, VF or cardiac arrest
S ICD
ICD, implantable cardioverter defibrillator; SVT, sustained ventricular tachycardia; VF, ventricular fibrillation.
4.
Ventricular Tachycardia/Fibrillation Associated With 2. Mitral Valve Prolapse
Short QT Intervals Mitral valve prolapse had attracted interest as a cause of sudden
A few cases of VT/VF associated with subnormal short QT death since it was the single and only abnormal finding on
intervals on ECG have been reported.146 autopsy in patients died from sudden death of unknown
The use of an ICD is indicated for secondary prevention of cause.154,155 However, it was then found that sudden death is
sudden death in these patients, and catheter ablation may cure extremely rare among patients with mitral valve prolapse with-
this condition in some cases. It is difficult to predict high risk out mitral regurgitation.156,157 The incidence of sudden death in
patients indicated for primary prevention. patients with mitral regurgitation (1.8%/year) is estimated 50 to
100-fold higher than those without mitral regurgitation. The risk
for sudden death among patients with mitral valve prolapsed
15. Valvular Heart Disease cannot be predicted with the presence/absence of arrhythmia.158
Also, QTD and the presence/absence of ventricular arrhythmia
1. Aortic Stenosis induced during EPS are not considered helpful in predicting
Aortic stenosis is the most common valvular heart disease caus- sudden death. Although the presence/absence of mitral regurgi-
ing sudden death. It has been reported that sudden death occurs tation significantly affects the incidence of sudden death, the
in 15 to 20% of adult patients with aortic stenosis (mean age: significance of echocardiography in risk assessment has not
60 years) and 44 of 70 patients died from sudden death during been investigated in detail. Patients with SVT or VF are indi-
survey.147,148 The most common causes of sudden death in pa- cated for secondary prevention using an ICD (Table 14).
tients with aortic stenosis are considered VF and SVT. Patients
with SVT and VF (after cardiopulmonary resuscitation) should 3. Patients After Prosthetic Valve Replacement
undergo secondary prevention mainly with ICD therapy. It has been reported that the incidence of sudden death during
Although aortic pressure gradient is an effective measure of the late phase after valve replacement with the St. Jude Medi-
severity of valvular stenosis, it is not useful in predicting sudden cal prosthesis ranged 0.5 to 2.4%,159,160 while the incidence of
death. Arrhythmia findings of Holter ECG correlate with the sudden death after replacement with bioprosthetic valves was
interventricular septal wall thickness, left ventricular mass, and as low as 0.2 to 1%.161 It is believed that sudden death in
the decrement of LVEF.149–152 Patients with a QTD of ≥70 msec patients using mechanical valves is often related to heart fail-
are at high risks of developing syncopes and cardiac arrest.5,153 ure, MI or fatal arrhythmia.161 Secondary prevention is essen-
Patients with hemodynamically significant valvular stenosis tial for patients with VT/VF, but prediction and primary pre-
are indicated for surgery (Table 13). vention of sudden death among patients after valve replacement
have not been established yet.
III Prevention of Sudden Death in Children
The most common causes of sudden cardiac death in children
in Japan are cardiomyopathy, congenital heart diseases and 1. Sudden Infant Death Syndrome
arrhythmias.162,163 HCM is the most common cardiomyopathy
leading to sudden death in children, and arrhythmias leading Several factors and causes have been pointed out for sudden
to sudden death include VF, complete atrioventricular block, death in infants. Although there is an opinion that sudden
LQTS and WPW syndrome. Major pathological conditions death with known causes should not be included in sudden
and diseases are described in the following subsections. infant death syndrome (SIDS), this section includes sudden
death with known causes to ensure appropriate management.
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11. JCS Guidelines for Risks and Prevention of Sudden Cardiac Death 499
Table 15. Prevention of Sudden Infant Death Syndrome in Infants With Long QT Syndrome
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• nfants resuscitated from SIDS with a QTc of ≥440 msec
I ICD
β-blockers
Primary prevention
• nfants whose elder siblings died from SIDS with a QTc
I ICD
of ≥440 msec β-blockers
• nfants without a family history of SIDS with a QTc of
I β-blockers
≥440 msec
ICD, implantable cardioverter defibrillator; SIDS, sudden infant death syndrome.
Table 16. Prevention of Sudden Infant Death Syndrome in Infants With Impulse Conduction Disorders
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• esuscitated infants
R Pacemaker
Primary prevention
• nfants with familial impulse conduction disorders
I Pacemaker
Table 17. Prevention of Sudden Infant Death Syndrome in Infants With Abnormal Fatty Acid Metabolism
Purpose of treatment/findings Class I Class IIa Class IIb
Primary prevention Common preventive methods:
Frequent high carbo low fat meals
Limit long-chain fatty acids and
take middle-chain fatty acids
• arnitine transporter deficiency
C
• PT-II deficiency
C
• A translocase deficiency
C
• CAD deficiency
L +L-carnitine
• LCAD deficiency
V +L-carnitine
• CHAD/trifunctional protein deficiency
L +L-carnitine
CA translocase, carnitine-acylcarnitine translocase; CPT-II, carnitine palmitoyltransferase type II; LCAD, long-chain
acyl-coenzyme A dehydrogenase; LCHAD, long-chain 3-hydroxyacyl-CoA dehydrogenase; VLCAD, very-long-chain
acyl-CoA dehydrogenase.
1. Long QT Syndrome tion, atrioventricular block, left bundle branch block and other
In an investigation of a relationship between SIDS during types of arrhythmia responsible for SIDS.170 Appropriate dietary
neonatal period and the QT prolongation, infants with a QTc therapy and drug treatment are recommended for children with
≥440 msec were at a high risk of sudden death (Table 15).164 abnormal fatty acid metabolism (Table 17).
2. SCN5A Gene Mutation
SCN5A gene mutation was reported in about 2% of infants 2. Arrhythmias
died from SIDS.165–167 Since it is difficult to predict sudden
death, patients with SCN5A gene mutation are indicated for 1. WPW Syndrome
secondary prevention mainly using an ICD. However, it is Although there are electrophysiological findings suggesting a
difficult to implant an ICD to children with small body size. high risk of sudden death (VF), it has been pointed out sudden
death in children cannot be predictable with EPS.119,123,171 Cura-
3. Impulse Conduction Disorders tive treatment using catheter ablation is indicated for patients
Fasciculoventricular tracts were significantly frequently with WPW syndrome to prevent sudden death (see Table 11).
observed during autopsy of infants died from SIDS.168,169 It is
difficult to predict such findings. Children with a history of 2. Ventricular Tachycardia and Catecholamine-Induced
cardiac arrest due to atrioventricular block are indicated for Polymorphic Ventricular Tachycardia
pacemaker. Primary prevention is recommended for children Sudden death due to VT is observed even in children under 5
with familial impulse conduction disorders (Table 16). years.172 ICD therapy is indicated for children with VT/CPVT,
but implantation is not feasible due to small body size and lead
4. Abnormal Fatty Acid Metabolism troubles associated with bodily movement and development. It
It has been reported that disorders of mitochondrial fatty acid has been reported that catheter ablation is effective. The treat-
β-oxidation cause accumulation of long-chain acylcarnitine, ment are similar to those recommended for adult patients.124,132,139
which may lead to VT, atrial tachycardia, sinus node dysfunc- See the section of CPVT in adults.
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12. 500 JCS Joint Working Group
Table 18. Prevention of Sudden Death in Children With Long QT Syndrome
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• atients with syncope not responding
P ICD
to drug treatment +β-blockers
Mexiletine*1
Mg*2
• ymptomatic patients
S Pacemaker
+β-blockers
Mexiletine*1
Mg*2
Primary prevention
• symptomatic patients
A Drug treatment same as above Appropriate guid-
ance on exercise
*1LQT2 or LQT3 mutation with severe atrioventricular block is often observed in neonates and infants with long QT
syndrome. The good efficacy of mexiletine in this patient population has been described in many reports. *2Use for
torsades de pointes.
ICD, implantable cardioverter defibrillator; Mg, magnesium.
Table 19. Prevention of Sudden Death Related to Commotio Cordis
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• esuscitated patients
R Prohibit from exercise which may
cause chest wall impact
Use chest protectors
Use softer balls
Primary prevention Use chest protectors
Use softer balls
Table 20. Prevention of Sudden Cardiac Death in Children With Hypertrophic Cardiomyopathy
Purpose of treatment/findings Class I Class IIa Class IIb
Secondary prevention
• hildren resuscitated from near-miss sudden death
C ICD
with a history of syncope or symptomatic VT or a Drug treatment†
first-degree family history of sudden death
Primary prevention
• ymptomatic children or high-risk children*
S ICD*, β-blockers, calcium channel block-
ers‡, disopyramide (or cibenzoline)
*See the section of adult HCM. †Digitalis, ACE inhibitors and nitrates are contraindicated for patients without heart
failure (special care should be taken for infants) or dilated phase HCM. ‡Calcium channel blockers are not recom-
mended for patients with severe left ventricular outflow obstruction.
ACE, angiotensin converting enzyme; HCM, hypertrophic cardiomyopathy; ICD, implantable cardioverter defibrillator;
VT, ventricular tachycardia.
3. Long QT Syndrome Holter ECG). Since it is well known that children with LQT1
LQTS is one cause of sudden cardiac death due to arrhythmia mutation often experience drowning or near-drowning acci-
in children. ECG check-ups in schools are common in Japan, dents during swimming, swimming is commonly prohibited
and the prevalence of asymptomatic QT prolongation is esti- or limited in these children. It is important to provide appro-
mated as 1 in 1,200 children.173 Symptoms are believed to priate guidance on exercise (Table 18). See the section of
develop in 1 in 10 children with asymptomatic LQTS. SIDS for the relationship between LQTS and SIDS.
Onset of LQTS during neonatal period and infancy is prev- The Research Committee on Management of Children with
alent among patients with LQT2 or LQT3 mutations, and LQTS of Japanese Society of Pediatric Cardiology and Car-
mexiletine has been reported to be effective in the treatment diac Surgery is conducting a prospective study of children
of LQTS.174,175 Poor compliance with drug treatment is a risk with asymptomatic LQTS, and is expected to propose guide-
factor of arrhythmic accidents.175 lines for primary prevention for such children.182
Patients who still have arrhythmias during treatment with
antiarrhythmic drugs such as β-blockers and mexiletine, a
pacemaker or an ICD is implanted.176–181 There are no reports 3. Commotio Cordis
of large-scale studies in children with LQTS.
Treatment strategies for LQTS are determined according to Commotio cordis is a noticeable condition defined as sudden
the results of genetic tests, family histories of sudden death death triggered by relatively mild mechanical impact to the
and syncope and ECG findings (eg, exercise stress ECG and chest observed among athletes.183,184 The cause of death is
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13. JCS Guidelines for Risks and Prevention of Sudden Cardiac Death 501
Table 21. Classification of Severity of Cardiovascular Lesions in Kawasaki Disease
Severity classification Findings (echocardiography and selective coronary angiography)
I coronary dilatation
No Patients with no coronary dilatation including those in the acute phase
II
Transient coronary dilatation Patients with slight and transient coronary dilatation which typically subsides
during the acute phase within 30 days after onset
III
Regression Patients who exhibit coronary aneurysms on day 30 after onset, but disappear-
ance in the b]ilateral coronary artery systems within one year after onset, and
do not meet the criteria for Group V
IV
Residual coronary aneurysms Patients with unilateral or bilateral coronary aneurysms detected by coronary
angiography in the second year or later and do not meet the criteria for Group V
V
Coronary stenotic lesions Patients with coronary stenotic lesions detected by coronary angiography
(a) o ischemic findings: patients without ischemic signs/symptoms detectable
N
by laboratory tests or other examinations
(b) ith ischemic findings: patients with ischemic signs/symptoms detectable
W
by laboratory tests or other examinations
Note) ther clinical symptoms of findings: When patients have moderate or severe valvular heart disease, heart failure,
O
severe arrhythmia, or other cardiac disease, such conditions should be described in addition to the severity of
Kawasaki disease.
Adapted from Guidelines for Diagnosis and Management of Cardiovascular Sequelae in Kawasaki Disease (JCS 2008).199
Table 22. Indications of Treatment by Classification of Severity of Coronary Artery Lesions in Kawasaki
Disease
Treatment Class I Class II Class III
Antiplatelet drugs*1 IV, V III I, II
Anticoagulant drugs*2 IV, V III I, II
Coronary vasodilators*3 V IV I, II, III
Drugs for heart failure*4 V IV I, II, III
Coronary intervention*5 V(b) V(a) I, II, III, IV
Coronary bypass surgery V(b) V(a) I, II, III, IV
*1Aspirin, dipyridamole, and ticlopidine, *2Warfarin, heparin, *3Such as calcium cannel blockers and nitrates, *4ACE
inhibitors, angiotensin receptor blockers and β-blockers, *5Intracoronary thrombolysis (urokinase, tissue plasminogen
activators), coronary balloon angioplasty, stenting, and coronary angioplasty using rotablators.
ACE, angiotensin converting enzyme.
Adapted from Guidelines for Diagnosis and Management of Cardiovascular Sequelae in Kawasaki Disease (JCS
2008).199
believed to be arrhythmias triggered by blunt trauma to the
chest wall. Commotio cordis often develops in players of
5. Pediatric Hypertrophic Cardiomyopathy
baseball, soft ball and ice hockey, but has also been reported
during football, soccer, rugby, lacrosse, boxing and karate as HCM is the most important cause of sudden death in chil-
well as when someone deliver a knee kick to the chest or hit dren.91,190–194 Children with HCM with a history of resuscitated
the chest with a hand or fist.184,185 from near-miss sudden death, syncope or symptomatic VT or
Prompt cardiopulmonary resuscitation should be initiated. a first-degree family history of sudden death are indicated for
Chest protecters are used to prevent commotion cordis, but the ICD therapy according to the criteria in each institution or
benefit is limited since it has been reported that 28% of indi- American College of Cardiology/American Heart Associa-
viduals died from commotio cordis wore chest protecters.185 tion/North American Society of Pacing and Electrophysiology
Further safety measures such as using softer balls should be (ACC/AHA/NASPE) recommendations.117
considered (Table 19). It is unclear that whether septal myectomy, pacemaker
implantation and percutaneous transluminal septal myocardial
ablation (PTSMA) used for adult patients with HCM are effec-
4. Congenital Heart Diseases tive secondary preventive methods for children or not.190,195
Drug treatment is recommended as both primary and second-
Sudden death after surgery for congenital heart diseases has ary prevention. β-blockers, calcium channel blockers, diso-
been observed.186,187 The incidence of sudden death after sur- pyramide (or cibenzoline) are used (Table 20).71,190 It has been
gery is relatively high in patients with tetralogy of Fallot and reported that highdose β-blocker treatment (5 to 23 mg/kg/day)
patients with complete transposition of great arteries.187–189 is highly effective,160 but some studies have denied such
Secondary prevention is indicated for patients who experi- effects.71
enced syncope, symptomatic VT or resuscitated from near- Pediatric HCM is characterized by the higher prevalence of
miss sudden death. Since criteria for ICD therapy in children heart failure and poorer prognosis among children in whom
with congenital heart diseases are not available, guidelines for HCM developed during infancy than those with later onset.196,197
adult patients should be referred.22 Physicians should refer to the School Activity Management
Table published by the Japanese Society of School Health for
level of exercise limitation and lifestyle guidance.71
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