Brugada Syndrome Summary

Overview

  • Inherited arrhythmogenic disease
  • Characteristic ECG patterns
  • Risk of sudden cardiac death
  • 80% of affected individuals are men

ECG Patterns

  • Type 1: Coved ST elevation ≥2mm (diagnostic)
  • Type 2: Saddleback pattern (suggestive)
  • Type 3: Saddleback/coved <1mm (suggestive)

Diagnosis

  • Type 1 ECG + clinical criteria
  • Exclude other causes of ST elevation
  • Drug challenge if ECG inconclusive

Risk Factors

  • Previous SCD/syncope
  • Spontaneous type 1 ECG
  • Male sex
  • Inducible VT/VF on EP study

Management

  • ICD: Primary treatment for high-risk
  • Avoid arrhythmogenic drugs
  • Aggressive fever treatment
  • Family screening

Drug Challenge

  • Flecainide, ajmaline, procainamide
  • Right precordial leads in 2nd ICS
  • Positive: conversion to type 1 pattern

Clinical Criteria

  • Family history of SCD <45 years
  • Syncope/seizures
  • Documented VT/VF
  • Nocturnal agonal respiration

Brugada Syndrome (BS)

An inherited arrhythmogenic disease characterized by coved-type ST-segment elevation and risk of sudden cardiac death

Introduction

ECG Patterns

Three repolarization patterns in right precordial leads (V1-V3):

Type 1 (Diagnostic)

  • Prominent coved ST-segment elevation ≥2mm
  • Followed by negative T wave
  • Only definitive diagnostic pattern

Type 2 (Suggestive)

  • ≥2mm J-point elevation
  • ≥1mm ST-segment elevation
  • Saddleback appearance
  • Positive/biphasic T-wave

Type 3 (Suggestive)

  • Saddleback or coved appearance
  • ST-segment elevation <1mm

Drug Challenge Testing

  • Indicated when BS is suspected but ECG is normal or shows type 2/3
  • Class I antiarrhythmics used: flecainide, ajmaline, procainamide, etc.
  • Positive test: conversion to type 1 pattern
  • Right precordial leads should be placed in 2nd intercostal space for higher sensitivity

Diagnosis

Requires:

  1. Type 1 ECG (spontaneous or drug-induced) in >1 precordial lead
  2. Exclusion of other causes of ST elevation
  3. Plus at least one clinical criterion:

Family History

  • SCD in family member <45 years
  • Type 1 ECG in family members

Symptoms

  • Syncope
  • Seizures
  • Nocturnal agonal respiration

Documented Arrhythmias

  • Polymorphic VT
  • Ventricular fibrillation

Without clinical criteria, type 1 ECG should be called "idiopathic Brugada ECG pattern" not Brugada syndrome

Risk Stratification

25% of BS patients will experience SCD or VF in their lifetime

Risk Factor Implications
SCD survivors High risk of recurrence → ICD indicated
Syncope High risk after excluding non-cardiac causes → ICD indicated
Spontaneous type 1 ECG Higher risk when combined with syncope and inducible VT/VF on EP study
Male sex More arrhythmic events and worse prognosis than women

Management

Primary Treatment

ICD implantation is the only proven effective therapy for SCD prevention

Note: High rate of inappropriate shocks due to sinus tachycardia, SVT, and lead complications

Other Recommendations