Guidelines Summary
Diagnosis
In its 2013 expert consensus statement on inherited primary arrhythmia syndromes, the Heart Rhythm Society/European Heart Rhythm Association/Asia Pacific Heart Rhythm Society (HRS/EHRA/APHRS) recommended a diagnosis of Brugada syndrome (BrS) when the following criteria are met [44] :
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ST-segment elevation with type I morphology ≥2 mm in ≥1 lead among the right precordial leads V1,V2 positioned in the 2nd, 3rd, or 4th intercostal space occurring either spontaneously or after provocative drug test with intravenous administration of Class I antiarrhythmic drugs
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Type 2 or type 3 ST-segment elevation in ≥1 lead among the right precordial leads V1,V2 positioned in the 2nd, 3rd, or 4th intercostal space when a provocative drug test with intravenous administration of class I antiarrhythmic drugs induces a type I ECG morphology
In 2015, the European Society of Cardiology (ESC) released guidelines for the management of ventricular arrhythmias and the prevention of sudden cardiac death (SCD) thatincluded the following specific recommendation for diagnosis of BrS. [45]
Class I (Level of evidence: C)
Brugada syndrome is diagnosed in patients with ST-segment elevation with type 1 morphology ≥2 mm in one or more leads among the right precordial leads V1 and/or V2 positioned in the second, third, or fourth intercostal space, occurring either spontaneously or after provocative drug test with intravenous administration of sodium channel blockers (such as ajmaline, flecainide, procainamide or pilsicainide).
Genetic testing
In 2011, the Heart Rhythm Society (HRS) and the European Heart Rhythm Association (EHRA) issued a joint expert consensus statement on genetic testing for channelopathies and cardiomyopathies with the following recommendations for BrS testing [46] :
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Consider comprehensive or BrS1 (SCN5A) targeted genetic testing for individuals with strong clinical index of suspicion for BrS based on clinical history, family history, and expressed electrocardiographic phenotype (class IIa)
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Mutation specific genetic testing for family members following identification of BrS mutation in an index case (class I)
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Genetic testing is not indicated in the setting of an isolated type 2 or type 3 Brugada ECG pattern (class III)
Management and prevention of sudden cardiac death
The following is a summary of recommendation included in the 2015 ESC guidelines for management of of LQTS and preventions of SCD. [45]
Class I (Level of evidence: C)
Lifestyle changes:
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Avoidance of drugs that may induce ST-segment elevation in right precordial leads
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Avoidance of excessive alcohol intake and large meals
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Prompt treatment of any fever with antipyretic drugs.
ICD implantation in patients who are survivors of an aborted cardiac arrest and/or have documented spontaneous sustained ventricular tachycardia (VT).
Class IIa (Level of evidence: C)
Consider ICD in patients with a spontaneous diagnostic type I ECG pattern and history of syncope.
Consider quinidine or isoproterenol to treat electrical storms.
Consider quinidine for patients who qualify for an ICD but present a contraindication or refuse it and in patients who require treatment for supraventricular arrhythmias.
Class IIb (Level of evidence: C)
Consider ICD in patients who develop ventricular fibrillation during programmed ventricular stimulation with two or three extra stimuli at two sites.
Consider catheter ablation in patients with a history of electrical storms or repeated appropriate ICD shocks.
The 2013 HRS/EHRA/APHRS guidelines offer consistent recommendations. In additiona, the guidelines find ICD implantation is not indicated in asymptomatic BrS patients with a drug-induced type I ECG and on the basis of a family history of sudden cardiac death (SCD) alone. [44]
A scientific statement published in 2015 by the American Heart Association and the American College of Cardiology on athletic competition by persons with known or suspected cardiac channelopathies includes the following recommendations related to BrS [43] :
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A heart rhythm specialist or genetic cardiologist experienced in cardiac channelopathies should conduct a thorough evaluation of an athlete in whom such a disorder has been diagnosed or is suspected (class I; level of evidence, C)
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Symptomatic athletes with any suspected or diagnosed cardiac channelopathy should be restricted from all competitive sports until a comprehensive evaluation has been completed, the athlete and his or her family are well informed, a treatment program has been implemented, and the athlete has been asymptomatic on therapy for 3 months (class I; level of evidence, C)
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Asymptomatic athletes who are genotype-positive/phenotype-negative for Brugada syndrome can be allowed to take part in all competitive sports if precautionary measures are taken, such as avoidance of drugs that exacerbate BrS, electrolyte/hydration replenishment and avoidance of dehydration, avoidance or treatment of hyperthermia from febrile illnesses or training-related heat exhaustion or heat stroke, possession of a personal automatic external defibrillator as part of the athlete’s personal sports safety gear, and establishment of an emergency action plan with the appropriate school or team officials (class IIa; level of evidence, C)
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Competitive sports participation may be considered for an athlete with either previously symptomatic or electrocardiographically evident BrS, assuming appropriate precautionary measures and disease-specific treatments are in place and the athlete has been asymptomatic on treatment for at least 3 months (although treatment involving an implantable cardioverter-defibrillator is subject to additional recommendations) (class IIb; level of evidence, C)
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Schematics show the 3 types of action potentials in the right ventricle: endocardial (End), mid myocardial (M), and epicardial (Epi). A, Normal situation on V2 ECG generated by transmural voltage gradients during the depolarization and repolarization phases of the action potential. B-E, Different alterations of the epicardial action potential that produce the ECG changes observed in patients with Brugada syndrome. Adapted from Antzelevitch, 2005.
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Three types of ST-segment elevation in Brugada syndrome, as shown in the precordial leads on ECG in the same patient at different times. Left panel shows a type 1 ECG pattern with pronounced elevation of the J point (arrow), a coved-type ST segment, and an inverted T wave in V1 and V2. The middle panel illustrates a type 2 pattern with a saddleback ST-segment elevated by >1 mm. The right panel shows a type 3 pattern in which the ST segment is elevated < 1 mm. According to a consensus report (Antzelevitch, 2005), the type 1 ECG pattern is diagnostic of Brugada syndrome. Modified from Wilde, 2002. Image courtesy of Richard Nunez, MD, and EMedHome.com (http://www.emedhome.com/).
Tables
Characteristic |
Type 1 |
Type 2 |
Type 3 |
J wave amplitude |
≥2 mm |
≥2 mm |
≥2 mm |
T wave |
Negative |
Positive or biphasic |
Positive |
ST-T configuration |
Cove-type |
Saddleback |
Saddleback |
ST segment, terminal portion |
Gradually descending |
Elevated by ≥1 mm |
Elevated by < 1 mm |
