Prevalence of a Multiple Territory Stroke Pattern After Intravenous Thrombolysis

Abstract

Background: It has been proposed that the presence of a multiple territory stroke pattern (MTSP) on brain imaging may aid identification of patients with covert atrial fibrillation (AF). However, it is uncertain whether this association holds true among patients treated with intravenous recombinant tissue plasminogen activator (rtPA) because clot fragmentation may affect MTSP prevalence. Methods/Design: Retrospective analysis of 149 acute ischemic stroke patients treated with intravenous rtPA who underwent brain MRI. Presence of multiple acute infarctions on brain MRI that involved more than one vascular territory was considered to denote MTSP. Stroke etiology was categorized as nonembolic, cardioembolic (CES), and embolic stroke of undetermined source (ESUS). Results: In the entire cohort, subjects with CES and ESUS had significantly more often an MTSP than subjects with other determined stroke mechanism (P= .007). Although numerically relatively more patients had an MTSP as compared to a non-MTSP among subjects with CES (52% versus 33.9%) and ESUS (44% versus 34.7%), this difference did not reach significance after Bonferroni-adjustment for multiple comparisons (P> .05, each). There was no difference in the prevalence of an MTSP among subjects with known (n = 11/51; 21.6%) versus subsequently diagnosed (n = 1/3; 33.3%) AF (P= .54). Conclusions: Our findings indicate that the known association of multiterritory infarct with AF and ESUS is maintained after thrombolysis. In light of its high specificity, MTSP represents a good marker for AF-related stroke etiology; nevertheless, overall sensitivity for AF was low highlighting that an absent MTSP does not rule out AF.