Procainamide-Provoked Brugada Pattern in a Patient Presenting with New-Onset Atrial Fibrillation or Flutter: When Does it Matter?

BACKGROUND: Brugada syndrome (BrS) is an inherited disease that can lead to sudden cardiac death. Medications, such as antidysrhythmics, and fevers can unmask or induce the Brugada pattern on an electrocardiogram (ECG). This case report highlights a patient who developed drug-induced Brugada type I pattern after a procainamide infusion for the treatment of new-onset atrial fibrillation (AF) or flutter and discusses the implications for this incidental but potentially lethal finding.

CASE REPORT: We report a case of a young man who presented to the emergency department (ED) with new-onset AF with rapid ventricular response that began within 12 h of presentation. ED treatments included a crystalloid IV fluid bolus, diltiazem pushes, synchronized electrical cardioversion, and a procainamide infusion. After the procainamide infusion, the patient developed ECG findings consistent with Brugada pattern. Both the AF and Brugada pattern resolved spontaneously within 24 h. The patient was discharged without implantable cardioverter defibrillator placement due to presumed isolated procainamide-induced Brugada pattern and lack of concerning features, such as inducible dysrhythmia during electrophysiology study, family history of sudden death, and history of syncope. The patient was counseled to follow-up with genetics and avoid BrS-inducing medications. WHY SHOULD AN EMERGENCY PHYSICIANS BE AWARE OF THIS?: Procainamide, an option for the treatment of AF in the ED, can provoke Brugada pattern. If encountered, it is important to recall that some patients may not be diagnosed with BrS if determined to be low risk according to the Shanghai criteria. All patients should be referred to cardiology for further evaluation.