Delay in Diagnosis of Basilar Artery Stroke

Basilar artery stroke causes substantial morbidity and mortality. Although its unusual clinical presentation potentially contributes to a delay in diagnosis, this problem has not been systematically studied. We compared intervals between symptom onset, initial presentation, and diagnosis in stroke due to basilar artery (BA) versus left middle cerebral artery (LMCA) occlusion to determine the presence of and potential reasons for diagnostic delay in BA stroke.

We retrospectively identified 21 consecutive adult patients diagnosed with BA stroke between 2009 and 2011 from our hospital's prospective stroke registry. Patients were age-, sex-, and race-matched with 21 LMCA stroke patients from the same period. All subjects had confirmed clinical and radiographic diagnosis of stroke due to occlusion or stenosis of the BA, LMCA, or left internal carotid artery. Time to diagnosis was determined independently by two investigators through medical record review. The pre-specified primary outcome was latency from emergency department (ED) arrival to stroke diagnosis.

Median time from ED arrival to diagnosis was 8 h 24 min (IQR: 2:43-26:32) for BA and 1 h 23 min (IQR: 0:41-1:45; p < 0.001) for LMCA. Median time from symptom onset to ED arrival was 7 h 44 min (IQR 1:23-21:30) for BA and 1 h 2 min (IQR 0:36-9:41; p = 0.06) for LMCA. Four of 21 (19 %) BA patients were diagnosed within a 4-h time frame to make intravenous thrombolysis possible compared to 13 of 21 (62 %) LMCA patients (p = 0.01).

Our results suggest that both pre-hospital and in-hospital processes cause substantial, clinically significant delays in the diagnosis of BA stroke.