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Recurrent syncope with a type 1 Brugada electrocardiogram pattern in a patient on amitriptyline: Brugada syndrome vs.
Muhammad K Asyraf1, Philip Smyth1, Sajjad Matiullah1
1Department of Cardiology, University Hospital Waterford, Dunmore Road, Waterford, X91 ER8E, Ireland.
Background:
Brugada syndrome is an inherited arrhythmogenic channelopathy associated with an increased risk of sudden cardiac death. Diagnosis relies on the presence of a spontaneous type 1 Brugada pattern on electrocardiogram (ECG). While multiple hypotheses have been proposed to explain its underlying mechanism, it is generally thought to be secondary to defective myocardial sodium channels. For this reason, sodium channel-blocking medications can induce a type 1 Brugada pattern, which may complicate risk stratification and raise the possibility of Brugada phenocopy.
Case Summary:
A 44-year-old man on regular amitriptyline 75 mg for anxiety and panic disorder presented with two episodes of syncope. ECG showed classical features of a type 1 Brugada pattern. Routine blood investigations, including full blood count, renal function tests, a comprehensive electrolyte panel, and high-sensitivity troponin, were normal. Transthoracic echocardiography revealed normal cardiac structure and function. Following multidisciplinary team (MDT) discussion, and guided by the 2022 European Society of Cardiology (ESC) guidelines, a shared decision was made to proceed with implantable cardioverter-defibrillator (ICD) implantation. The patient was discharged with follow-up in the arrhythmia clinic and referred for genetic testing.
Discussion:
This case highlighted the diagnostic and management challenges of differentiating true Brugada syndrome from drug-induced Brugada phenocopy. Although our patient had type 1 Brugada ECG pattern in the context of amitriptyline use, his presentation with syncope complicates risk stratification. MDT discussion and reference to ESC guidelines played a key role in determining further management, which in this case was ICD implantation.
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