What is the management plan for a patient with symptomatic syncope and a history of Brugada syndrome?

Management of Symptomatic Syncope in Brugada Syndrome

An implantable cardioverter-defibrillator (ICD) is recommended for patients with Brugada syndrome who have a spontaneous type 1 ECG pattern and recent syncope presumed due to ventricular arrhythmia, provided meaningful survival greater than 1 year is expected. 1

Critical Initial Assessment: Distinguishing Arrhythmic from Non-Arrhythmic Syncope

The first priority is determining whether syncope is arrhythmic or non-arrhythmic, as this fundamentally changes management. Non-arrhythmic syncope occurs in 57% of Brugada patients with syncope and carries 0% annual cardiac arrest risk, compared to 8.7% per year in those with arrhythmic events. 2

Key Historical Features Suggesting Arrhythmic Syncope:

• Absence of prodromes (no warning symptoms before loss of consciousness) 2
• Specific trigger absence: Never triggered by hot/crowded surroundings, pain, emotional stress, seeing blood, or prolonged standing 2
• Urinary incontinence during the event (4.6 times more likely with arrhythmic events) 2
• Older age at first event (mean 45 years for arrhythmic vs 20 years for non-arrhythmic) 2
• Male sex (2.1 times higher risk for arrhythmic events) 2
• Events occurring during sleep or rest (due to increased vagal activity) 3, 4

Features Suggesting Non-Arrhythmic (Reflex) Syncope:

• Prodromes present (lightheadedness, nausea, diaphoresis) 2
• Triggered by specific situations: prolonged standing, hot environments, emotional stress, pain, or sight of blood 2
• Younger age at onset 2

Physical Examination and ECG Assessment

ECG Evaluation:

• Confirm spontaneous type 1 Brugada pattern: Coved ST-segment elevation ≥2 mm in V1 and/or V2 with negative T-waves 5, 4
• Use high electrode positioning in second and third intercostal spaces to improve detection 1, 5
• Recognize pattern variability: The type 1 pattern is transient and may be intermittent, present only during fever or vagotonic states 1, 5, 4
• Serial ECGs are essential as a single normal ECG does not exclude the diagnosis 5

Physical Examination Focus:

• Assess for structural heart disease (though typically absent in Brugada syndrome) 4, 6
• Evaluate for orthostatic hypotension (suggests non-arrhythmic cause) 2
• Document any fever at presentation (can unmask ECG pattern and trigger arrhythmias) 1, 3, 5

Risk Stratification Algorithm

High-Risk Features Requiring ICD:

1. Spontaneous type 1 ECG pattern (worse prognosis than drug-induced pattern) 5
2. Syncope presumed arrhythmic based on historical features above 1
3. 6-fold higher cardiac arrest risk compared to asymptomatic patients with spontaneous pattern 5

Lower-Risk Features:

• Drug-induced type 1 pattern only (not spontaneous) 5
• Clear non-arrhythmic syncope mechanism identified 2
• Asymptomatic with only inducible pattern 1

Management Plan

For Symptomatic Patients with Presumed Arrhythmic Syncope:

Primary Recommendation:

• ICD implantation is the Class I recommendation for patients with spontaneous type 1 pattern and syncope presumed due to ventricular arrhythmia 1
• Secondary prevention ICD data shows nearly one-third receive appropriate therapy, far exceeding device complications 7

Alternative Management (if ICD declined or contraindicated):

• Quinidine is recommended as an alternative (Class I recommendation for those who decline or are not candidates for ICD) 1, 3
• Catheter ablation of epicardial substrate in right ventricular outflow tract is an alternative option 1, 4

For Patients with Suspected Non-Arrhythmic Syncope:

Consider Implantable Loop Recorder (ILR):

• ILR can exclude ventricular arrhythmia as syncope mechanism in atypical cases 8
• In one series, 50% of symptomatic Brugada patients with ILR showed bradycardia (AV blocks, sinus bradycardia) rather than ventricular arrhythmias during events 8
• No ventricular arrhythmias were detected during symptomatic events in patients with atypical syncope 8
• This approach avoids unnecessary ICD implantation in patients with non-arrhythmic syncope 8

Universal Preventive Measures (All Patients):

Lifestyle Modifications:

• Aggressive fever management with antipyretics (fever triggers 27% of life-threatening events in young patients) 3, 5
• Avoid QT-prolonging and sodium channel blocking drugs (see www.brugadadrugs.org) 1, 3, 5
• Avoid excessive alcohol intake 1, 5
• Avoid cocaine and certain psychotropic/anesthetic agents 1, 3, 5

Activity Restrictions:

• Most high-intensity activities are permitted (rated 2-4/5) as arrhythmias typically occur at rest/sleep 3
• Caution with activities risking traumatic injury during loss of consciousness: free weights, downhill skiing, motorcycling, horseback riding (rated 1-2/5) 3
• Water sports including scuba diving require careful consideration (rated 0/5) due to drowning risk 3

Family Screening:

• Genetic counseling and testing may be useful to facilitate cascade screening of relatives (Class IIb recommendation) 1
• SCN5A mutations account for 20-30% of cases, though negative genetic testing does not exclude diagnosis 1, 5, 6
• Screen first-degree relatives with ECG, including provocative testing if indicated 5

Common Pitfalls to Avoid

1. Assuming all syncope in Brugada syndrome is arrhythmic: 57% is non-arrhythmic reflex syncope with excellent prognosis 2
2. Relying on single ECG: The type 1 pattern is intermittent and requires serial ECGs or provocative testing 1, 5, 4
3. Missing electrode positioning: Standard placement may miss the diagnostic pattern; use high positioning in 2nd-3rd intercostal spaces 1, 5
4. Overlooking fever as trigger: Fever can acutely precipitate cardiac arrest and must be aggressively treated 1, 3, 5
5. Not considering ILR in atypical cases: This can prevent unnecessary ICD implantation when syncope mechanism is unclear 8

Follow-Up Considerations

• Annual arrhythmic event rates: 13.5% in cardiac arrest survivors, 3.2% in syncope patients, 1% in asymptomatic patients 3
• Spontaneous type 1 pattern and symptoms at diagnosis are the strongest predictors of life-threatening arrhythmias in young patients 3
• If ICD implanted: Monitor for appropriate and inappropriate shocks; consider quinidine or ablation for recurrent shocks 1