ABSTRACT NUMBER: ESOC2026A1134 ASSOCIATION BETWEEN LEFT ATRIAL APPENDAGE CONTRAST FILLING CHARACTERISTICS ON CARDIAC CT AND RECURRENT STROKE

Abstract Background and aims We investigated the association between left atrial appendage (LAA) filling patterns on cardiac CT and long-term outcomes after ischemic stroke. Methods In this pre-specified subanalysis of the AIS of HEARTS study, acute ischemic stroke (AIS) patients (May 2018-March 2023) undergoing cardiac CT during the acute stroke imaging protocol were categorized as having LAA thrombus (low-attenuated, well-defined filling defect), slow-flow (filling defect not meeting thrombus criteria), or normal filling. We evaluated two-year functional outcome (modified Rankin Scale), recurrent ischemic stroke, and major adverse cardiovascular events (MACE) using ordinal and Cox regression, with sensitivity analysis in cryptogenic stroke. Results Among 2825 patients (57% male; median age 73 [IQR 63–82] years), 149 (5%) had LAA thrombus, 456 (16%) slow-flow, and 2220 (79%) normal filling. Thrombus and slow-flow patients had a higher prevalence of known AF (66%, 52%, and 15%; P < 0.001) and baseline NIHSS (median 12, 8 and 5, P < 0.001). In adjusted analyses, thrombus was associated with worse functional outcome (acOR 1.79 95%CI [1.23–2.61]), whereas slow-flow was not (acOR 1.02 [0.82–1.2]). Neither thrombus or slow-flow were associated with MACE (aHR 1.26 [0.93-1.72] and aHR 1.14 [0.92–1.41]) or overall recurrent ischemic stroke (aHR 1.08 [0.59-1.98] and aHR 1.06 [0.76–1.49]), but slow-flow was associated with recurrence in cryptogenic stroke patients (n = 443, aHR 2.39 [1.03–5.54]). Conclusions LAA thrombus was associated with worse two-year functional outcome, whereas slow-flow was not. Slow-flow and thrombus were not associated with MACE or overall stroke recurrence, but slow-flow was associated with recurrent stroke in cryptogenic stroke. Conflict of interest The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: DSG repports funding by the Australian Government Research Training Program Scholarship. SSN received travel grants from the Cultuurfondsbeurs, Remmert Adriaan Laan Fonds, CONTRAST consortium and Dr. Jan Meerwaldt Stichting outside the submitted work. ABN has received research funding from the Neurological Foundation of New Zealand, outside the submitted work. CGE has received travel funding for travel for conferences from Boehringer Ingelheim and Bayer and speaker honoraria from Astra Zeneca, outside the submitted work. JMC reports grants from Medtronic, Siemens, AstraZeneca and Bayer outside the submitted work (all paid to institution). JMC is shareholder and co-founder of TrianecT. LAR was supported by a personal Dekker Junior Clinical Scientist Grant from the Dutch Heart Foundation. The other authors have no financial conflicts of interest.