Abstract: Objective To investigate the impact of vulnerable plaque screening using carotid high-resolution magnetic resonance imaging (HR-CMR) on the effectiveness of secondary prevention in patients with transient ischemic attack (TIA)/minor stroke. Methods Patients with TIA/minor stroke admitted to our hospital between February 2021 and February 2024 was enrolled. Based on patient preference, they were allocated to a control group (n=414) or an observation group (n=420). A 1∶1 propensity score matching was performed to balance the baseline characteristics, resulting in 392 matched pairs in each group. The control group received standard secondary prevention therapy and follow-up according to established clinical guidelines. In the observation group, patients were stratified into high-risk and low-risk subgroups based on the findings of vulnerable plaque screening via HR-CMR and received targeted preventive strategies accordingly. The outcomes of interest, including stroke recurrence rates, medication adherence, imaging characteristics, adverse events, and cost-effectiveness, were compared between the two groups. Results In the final analysis, 32 patients from the control group and 14 from the observation group were lost to follow-up. The one-year stroke recurrence rate in the observation group was significantly lower than that in the control group, and the time to recurrence was longer (P<0.05). Post-intervention, both groups exhibited a reduction in plaque thickness, plaque length, intraplaque hemorrhage, and fibrous cap rupture compared to baseline; however, these improvements were significantly more pronounced in the observation group (P<0.05). Medication adherence was significantly higher in the observation group compared to the control group (P<0.05). There was no statistically significant difference in the incidence of various adverse reactions between the two groups (P>0.05). A cost-effectiveness analysis revealed an incremental cost-effectiveness ratio (ICER) of 219.80 RMB/% (ΔC/ΔE), indicating that an additional expenditure of 219.80 RMB was associated with the prevention of one additional case of stroke recurrence. This suggests a superior cost-effectiveness advantage for the intervention strategy employed in the observation group. Conclusions The application of vulnerable plaque screening based on HR-CMR in the secondary prevention of TIA/minor stroke can effectively reduce the rate of stroke recurrence, enhance plaque stability, and improve medication adherence without increasing the incidence of adverse events. Furthermore, this approach demonstrates a notable cost-effectiveness advantage.

Key words: Transient ischemic attack, Minor stroke, Carotid high-resolution MRI, Vulnerable plaque, Secondary prevention efficacy