Abstract Body: Background: The hyperintense acute reperfusion marker (HARM) sign is a hyperintense signal observed on postcontrast fluid-attenuated recovery inversion images and is strongly associated with cerebral ischemic insults. The clinical significance of the HARM sign in transient ischemic attack (TIA) has rarely been studied, unlike that in stroke. This study investigated the relationship between the HARM sign and various clinical factors in diffusion-weighted imaging (DWI)-negative TIA. Furthermore, we investigated the relationship between the HARM sign with recurrence of TIA and ischemic stroke.
Methods: We included 329 consecutive patients with DWI-negative TIA and divided them into two groups according to the HARM sign: 299 patients in the HARM(-) group and 30 patients in the HARM(+) group. Clinical information, brain imaging, and follow-up data were gathered from medical records and phone calls and compared using the HARM sign.
Results: The patients with HARM sign were older (70.7 vs. 64.4 years, p = 0.007), had more previous TIA or stroke history within 12 months (26.7% vs. 4.0%, p < 0.001), and had higher systolic blood pressure (154.3 vs. 144.1, p = 0.022). The HARM(+) group also had a shorter symptom duration of <1 hour (63.3% vs. 38.8%, p = 0.009) and more symptomatic stenosis (50–99%) or occlusion (60.0% vs. 14.0%, p < 0.001). Among the transient neurological symptoms, only cortical symptoms were more prevalent in the HARM(+) group (30.0% vs. 8.7%, p = 0.002). The total follow-up duration of both groups was similar, and the Kaplan-Meier analysis showed a higher cumulative incidence of recurrent stroke in the HARM(+) group (log-rank test, p = 0.007). However, multivariate Cox analysis indicated that symptomatic stenosis or occlusion, rather than the HARM sign, was independently associated with stroke recurrence.
Conclusion: The HARM sign in DWI-negative TIA patients is linked to older age, recent cerebrovascular events, shorter symptom duration, and large artery stenosis or occlusion. While the HARM sign correlates with higher recurrence of ischemic stroke, large artery stenosis or occlusion is the primary independent predictor.