Acute Neurological Deficit With New-Onset Atrial Fibrillation in a Patient With Carbon Monoxide Poisoning: A Stroke Mimic

We present the case of a middle-aged male from the Middle East with no prior history of cardiac disease who presented with syncope, nausea, and dizziness following smoking and barbeque in the desert outdoors. On arrival, he was found to have atrial fibrillation (AF), with a heart rate of 150-170 bpm. A diagnosis of carbon monoxide (CO) poisoning was made based on venous blood gas (VBG) analysis, showing a carboxyhemoglobin level of 33.9%. Treatment was initiated with a non-rebreather mask, followed by high-flow nasal cannula therapy, which resolved the symptoms and arrhythmia within a day. Cardiology follow-up confirmed the complete regression of AF. This case underscores uncommon but serious cardiac complications associated with CO poisoning. AF, although rare, may occur secondary to hypoxia-induced myocardial ischemia. Early recognition and prompt oxygen therapy are essential for optimal recovery, highlighting the importance of awareness when managing patients with CO poisoning with potential cardiac involvement.