The Heart‐Shaped Clue: Bilateral Medial Medullary Infarction Masquerading as Myasthenic Crisis

ABSTRACT Bilateral medial medullary infarction (BMMI) is a rare but potentially devastating stroke subtype that frequently mimics other neuromuscular disorders. We report the case of a 78‐year‐old man admitted for the evaluation of possible upper gastrointestinal disease who subsequently experienced fulminant neurological deterioration, including quadriplegia, cranial nerve involvement, and respiratory failure. While a myasthenic crisis was initially considered, magnetic resonance imaging (MRI) performed 27 h after symptom onset revealed a characteristic heart‐shaped hyperintensity in the medial medulla on diffusion‐weighted imaging (DWI), confirming BMMI. He received intensive care, including mechanical ventilation and combined anticoagulant and antiplatelet therapy, followed by tracheostomy, gastrostomy, and prolonged rehabilitation. At 6 months, he showed partial motor recovery and was able to communicate using assistive tools. This case highlights the diagnostic pitfalls of BMMI. Timely recognition of imaging features and maintaining a high index of suspicion are critical for early diagnosis and appropriate management.