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Erich Fogg, PA-C, MMSc, DEPARTMENT EDITOR
Alex Shalshin, MD, MS, PA-C; Ronald Lo, MD
Alex Shalshin works at Winthrop-University Hospital, Mineola, NY. Ronald Lo is a fellow in cardiology at Winthrop-University Hospital. The authors have indicated no relationships to disclose relating to the content of this article. Erich Fogg is Assistant Professor in and Program Director of the Physician Assistant Program at the College of Health Professions, University of New England, Portland, Me.
CASE
The patient is a 21-year-old male who experienced a nonwitnessed episode of syncope that resulted in a chin laceration. He was visiting his girlfriend’s parents, and after dinner with the family he retired to his room. He woke up to urinate at 2 AM, approximately 4 hours after falling asleep. The syncope occurred as he was making his way up the stairs; he regained consciousness surrounded by members of the family, who were awakened by the noise. The patient denied using alcohol or drugs, or any other activity that could have precipitated this event. There was no family history of sudden death. About 2 weeks previously, he had had symptoms of the flu but had completely recovered. The patient was awake with no neurologic or physical impairment. He had a 3-cm chin laceration with no active bleeding. Neurologic and cardiovascular examinations were normal. The patient was alert and oriented times three and scored 30/30 on the Mini-Mental State Examination. An ECG was obtained (see Figure 1), followed by an echocardiogram that demonstrated a structurally normal heart with normal function.
WHAT IS YOUR DIAGNOSIS?
• Acute anterior MI • Arrhythmogenic right ventricular dysplasia • Brugada syndrome • Angina pectoris
DISCUSSION
This patient has Brugada syndrome, an autosomal-dominant genetic condition with variable expression that can be easily diagnosed by ECG.1 Note the ST segment elevations in V1-V3 with the characteristic right bundle branch block pattern seen in this patient’s ECG. The incidence of Brugada syndrome is estimated at 0.05%
to 0.6% in adults and 0.0006% in children, suggesting that the syndrome manifests primarily during adulthood.2,3 The mean age at presentation is 35 to 40 years, but patients as young as 2 months and as old as 65 years have presented with the disease. Males with the syndrome outnumber females.4 Patients with Brugada syndrome have an estimated 30% chance of experiencing sudden cardiac death (SCD) within 3 years of diagnosis.5
Syncope or SCD is often the first clinical event in patients with Brugada syndrome, which should be suspected in those with documented idiopathic ventricular fibrillation (VF), self-terminating polymorphic ventricular tachycardia, a family history of SCD before age 45 years, syncope with the characteristic ECG changes, or a combination of these factors. The characteristic ECG changes in isolation represent an idiopathic Brugada ECG pattern, not necessarily Brugada syndrome. Such patients have a relatively low incidence of clinical events, suggesting that the majority are likely to remain asymptomatic. No pharmacologic treatment has been demonstrated to reduce the risk of sudden death. Both amiodarone and beta-blockers are less effective than implantable cardioverter defibrillators (ICDs) in patients with Brugada syndrome.6
Comment Mutations in the sodium channel gene SCN5A, located on chromosome 3p21-23, have been found in several families with Brugada syndrome.7 Recently, another mutation was identified on chromosome 3p22-25.8 However, this second mutation causes only a minority of cases.5
Patients with baseline ST-segment elevation and a history of syncope or idiopathic VF are at high risk of SCD and should have an ICD. Those with spontaneous ST-segment elevation or Brugada pattern ECGs without a history of syncope are considered at intermediate risk. The treatments for these patients are currently under debate. Patients who are carriers of the genetic mutation or who develop the Brugada ECG pattern may be reassured and advised to follow up if palpitations or syncope develops.8 •
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