Severity and Functional Outcome of Patients with Cardioembolic Stroke Occurring during Non-vitamin K Antagonist Oral Anticoagulant Treatment

Background: Severity and functional outcome of patients with cardioembolic stroke (CE) occurring during non-vitamin K antagonist oral anticoagulant (NOAC) treatment remain uncertain.

Methods: The consecutive 355 CE patients within 48 hours after onset and with modified Rankin Scale (mRS) score of 1 or less before onset were studied. Of all, 262 patients were treated with no anticoagulants (non-AC), 63 with warfarin below therapeutic range of prothrombin time-international normalized ratio (PT-INR) on admission (PT-INR <1.6 [WF-Lo]), 16 with warfarin within therapeutic range (PT-INR ≥1.6 [WF-Tp]), and 14 with NOACs (9 dabigatran and 5 rivaroxaban [NOAC-DR]). We compared severity and functional outcome of CE patients among these 4 groups, especially focusing on patients during NOAC treatment.

Results: Stroke severity on admission, assessed by the National Institutes of Health Stroke Scale, was lower in WF-Tp (median, 5 [1-15]) and NOAC-DR (5 [3-6]) than in non-AC (11 [5-19]) and WF-Lo (12 [5-19]; P = .006). Functional outcome at discharge, assessed by mRS, was favorable in WF-Tp (median, 1 [0-4]) and NOAC-DR (1 [1-2]) compared with that in non-AC (2 [1-4]) and WF-Lo (3 [1-5]; P = .02), and ratios of the patients with mRS score of 1 or less were 63% and 64% versus 31% and 33%, respectively (P = .005). Multivariate analysis also showed a favorable functional outcome at discharge in WF-Tp and NOAC-DR groups. Drug management was likely associated with NOAC-associated CE.

Conclusions: Stroke severity and functional outcome of CE patients treated with warfarin within therapeutic range and with NOACs are similar to each other, and are more favorable than those with no anticoagulants and with warfarin below therapeutic range.