A Case of Hyperthyroidism with Atrial Fibrillation Presenting as Ischemic Brain Stroke

We report the case of a 43-year-old man admitted for multiple ischemic strokes. Investigations revealed hyperthyroidism complicated by rapid atrial fibrillation (tachy AF). With no significant medical history, the patient presented with sudden aphasia and a mild motor deficit in the upper limbs. Imaging confirmed ischemic strokes of different ages and laboratory analyses showed very high levels of T3 and T4 with a suppressed TSH. Initial treatment included thiamazole for hyperthyroidism, propranolol for atrial fibrillation, and anticoagulation due to a CHADS-VASc score of 2. An echocardiogram revealed moderate mitral insufficiency and left atrial dilation. During hospitalization, the patient also had generalized convulsive seizures requiring anticonvulsant treatment. After appropriate management, the patient showed significant clinical improvement with a return to a regular sinus rhythm and normalization of hormone levels. This case highlights the importance of recognizing the interactions between endocrine and cardiovascular pathologies, particularly the impact of hyperthyroidism on atrial fibrillation and the increased risk of stroke. A multidisciplinary approach is essential for diagnosing and treating these complex conditions to prevent serious complications and improve patient prognosis.