Introduction: Brugada syndrome (BrS) is an inherited cardiac disease in which a characteristic ECG pattern of coved-type ST-segment elevation is seen in the right precordial leads. Patients are at increased risk of sudden cardiac death and usually present in the fourth decade of life but cases have been described in children. BrS should therefore be considered in a child presenting with cardiac arrest. Genetic pathogenic variants are found in only 30–35% of cases. A number of genes associated with BrS have been described, with the SCN5A gene being most frequently associated with the disease.
Case: A 14-month-old girl suffered a cardiac arrest at home. Parents started cardiopulmonary resuscitation and she was stabilised at the scene, including intubation and intraosseous access, by the pre-hospital emergency retrieval service before transfer to her local paediatric hospital. A broad complex tachycardia on admission to PICU quickly deteriorated to ventricular fibrillation. Resuscitation included four 4J/KG DC cardioversions, adrenaline and amiodarone as per paediatric resuscitation guidelines. A post arrest ECG showed ST-segment elevation in leads V1 and V2. A repeat ECG six hours later showed resolution of ST-segment elevation but persistent right bundle branch block pattern. Post cardiac arrest management included aggressive management of pyrexia and correction of electrolytes. Her transthoracic echocardiogram showed a structurally normal heart with normal coronary arteries. During recovery she experienced seizures secondary to hypoxic brain injury. Seizures were treated medically and she made a full neurological recovery. Investigations prior to discharge included a negative toxicology screen, positive virology for norovirus, rhinovirus, adenovirus and RSV, and normal parental ECGs. An ajmaline provocation test demonstrated a type 1 Brugada Syndrome ECG pattern. A hybrid implantable cardioverter defibrillator (ICD) was placed (combined epicardial subcutaneous lead with bipolar epicardial pacing/sensing lead and abdominal generator) and she was started on oral quinidine. Genetic testing revealed a novel likely pathogenic SCN5A splice variant (c.3841-2A>G, p.?) which has not been reported in the literature previously.
Discussion: Our patient displayed a severe phenotype of BrS at a young age and continues to have ECG changes despite medical management. ICDs remain the only proven treatment to prevent sudden cardiac death in children with BrS. The SCN5A gene is strongly associated with BrS though the novel pathogenic SCN5A splice variant in our patient has not been described in the literature.