Brugada phenocopy induced by tricyclic antidepressant poisoning

Tricyclic antidepressants (TCAs) are widely used to treat major depressive disorders. TCAs act mainly by inhibiting presynaptic reuptake of norepinephrine and serotonin in the central nervous system. Overdose of TCAs can result in devastating effects by antagonizing peripheral alpha-adrenergic, histaminic, muscarinic, and central serotonin receptors leading to a variety of adverse effects including anticholinergic toxicity and cardiac toxicity. In addition, blockade of fast sodium channels in myocardial cells leads to slowing of action potential, triggering conduction blocks and bradycardia.

 

Brugada phenocopy with electrocardiographic (ECG) evidence of Brugada syndrome can be found in acquired clinical circumstances following metabolic derangements and myocardial ischaemia. A few cases of Brugada phenocopy following TCA intoxication has been reported in the literature so far. We report a case of 56-year-old female who presented with acute intoxication of amitriptyline with ECG evidence of Brugada syndrome that ultimately led to pulseless ventricular tachycardia.