Case 1.   Suddenly Dizzy

The patient suddenly developed vertigo ("the room was spinning") while getting up out of his chair. He lost his balance, became nauseated, and vomited on the living room floor. He was able to call out for help, but when his wife came running in from the next room she immediately noticed that his speech was slurred and hard to understand. She immediately dialed 911.

The EMTs arrived about 20 minutes later and took him to the local hospital. He began to improve in the ambulance. By the time he arrived in the emergency room, he was speaking clearly again and could sit up. An electrocardiogram revealed atrial fibrillation. He was observed closely for the next 18 hours, but there were no further events and his neurologic exam showed no lasting deficits. Anticoagulation therapy was initiated.

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Expert Note Case 1.
Suddenly Dizzy

Diagrams

This patient had a brainstem TIA most likely produced by a cardiac embolus that initially lodged in one vertebral artery and then broke up.  The TIA lasted approximately an hour before the deficits began to clear. Like many patients with brainstem ischemia, he experienced problems related to malfunction of the vestibular system. Vertigo can have many causes, but the combination of vertigo and dysarthria suggests brainstem or cerebellar involvement.

Question
Why does atrial fibrillation increase the risk of TIA or stroke?
Answer
  • Ineffective contraction of the atrial muscle increases the likelihood that thrombus will form in the atrium. This is a potential source of emboli, which can travel to the brain producing a TIA, like this patient had, or a stroke.
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