Capsular Warning Syndrome - A Case Series and Discussion on Management Dilemmas

The term 'Capsular warning syndrome (CWS)' refers to recurrent, stereotypical transient ischemic attacks, either motor, sensory or both, without cortical symptoms or signs. Of these patients, 42-71% go on to develop infarcts. There are no defined treatment guidelines for this lesser known entity.

We studied 9 patients who presented over last 2 years to our hospital with recurrent and stereotypical transient ischemic attacks suggestive of capsular warning syndrome. Their clinical characteristics, neuroimaging findings, relevant etiological investigations, management and outcomes were studied.

Seven out of 9 patients were under 40 years of age. The commonest presentation in our series was a pure motor syndrome. The duration of neurologic deficits ranged from 5 minutes to 20 minutes with complete recovery in between episodes. Three patients had concordant abnormalities on CT brain angiography. Five out of 9 patients received IV thrombolysis with t-PA. One patient worsened neurologically post thrombolysis, whilst the others improved clinically.

Despite multiple hypotheses, the pathogenesis and management of CWS has not been established clearly. Due to fluctuating neurological symptoms with complete recovery in between the episodes, there is a dilemma concerning treatment of such patients with intravenous thrombolysis. However, intravenous thrombolysis appears to be safe in CWS as in acute ischemic stroke, followed by treatment with antiplatelet agents.