Clinical Characteristics and Outcome of the Capsular Warning Syndrome: A Multicenter Study

Background The capsular warning syndrome is defined as recurrent transient lacunar syndromes that usually precede a capsular infarction. Several aspects regarding the clinical management are controversial. We report the clinical and radiological characteristics of a multicenter series of patients with capsular warning syndrome, as well as their functional outcome during the follow-up. Aims We sought to describe the clinico-radiological spectrum of the capsular warning syndrome and to report the functional outcomes and recurrences of these patients during the follow-up. Methods We conducted a multicenter study that collected clinical and radiological data from patients with capsular warning syndrome during 2003–2013. Capsular warning syndrome was defined as the succession of three or more motor or sensory-motor lacunar syndromes within a period of 72 h, with complete recovery between them. We recorded the functional outcome (favorable when Rankin scale score ≤2) and recurrences during follow-up. Results Our study included 42 patients whose mean age was 66·4 ± 10 years; 71·4% of them were men. The mean number of episodes before a permanent neurological impairment occurred or before a complete recovery of symptoms was 5·1 ± 2·3. Up to 30 patients (71·2%) had an acute infarct visible on the neuroimaging (computed tomography/magnetic resonance imaging). The internal capsule was the most frequent infarct location (50%), but other locations were noted. Twelve patients (28·6%) received thrombolysis in the acute phase. A favorable outcome was observed in 39 patients (92·9%). After a mean follow-up of 35 ± 29 months, only one patient suffered a recurrent ischemic stroke. Conclusions Capsular warning syndrome preceded an ischemic infarction in 71·2% of patients. In addition to the internal capsule, other locations were noted. The most effective treatment remains unclear. The functional prognosis is favorable in most patients and recurrences are rare.