Abstract
We present the case of a 74-year-old male with a history of paroxysmal atrial fibrillation (PAF) and chronic kidney disease (CKD) who presented with fatigue. During hospitalization, telemetry captured an episode of hemodynamically stable wide-complex tachycardia consistent with monomorphic ventricular tachycardia. A 12-lead ECG revealed atrioventricular dissociation and a widened QRS complex. After discontinuing propafenone and initiating oral sodium bicarbonate due to limited intravenous availability, ECG abnormalities gradually improved over several hours, and the rhythm reverted to baseline PAF. A subsequent laboratory test confirmed supratherapeutic propafenone levels. This case highlights a temporally associated improvement in suspected propafenone cardiotoxicity with oral sodium bicarbonate in a hemodynamically stable patient. Written informed consent for publication was obtained.
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Copyright (c) 2026 Alok Arora, Ahmed Elsayed, Yousif Elsayed , Wadah Jason Ayoub, Alice Ching

