Abstract 4360016: Anatomical Stroke Topography Predicts Ventricular and Atrial Ectopic Burden

Introduction: Stroke-related autonomic dysregulation can trigger cardiac arrhythmias, but impact of stroke localization on ectopic burden is uncertain. Goals/Aims: Identify stroke locations associated with PVC/PAC burden to guide post-stroke cardiac monitoring. Methods: We retrospectively screened 150 consecutive adults admitted to a University Hospital stroke service for stroke (2023–2025). Inclusion criteria were radiologically confirmed stroke, 24-hour Holter monitoring, and no pre-existing arrhythmia and were met ( n=103). Stroke topography was classified by: (1) vascular territory (anterior cerebral artery [ACA], middle cerebral artery [MCA], posterior cerebral artery [PCA], multifocal, brainstem), (2) neuro-anatomical region (frontal, temporal, parietal, occipital, basal ganglia, insula, cerebellum), and (3) hemisphere (left, right, bilateral). Stroke etiology (ischemic vs hemorrhagic) was analyzed. Negative-binomial models, validated by deviance and Pearson residuals, quantified associations between stroke location and ectopic counts, adjusting for age, sex, hypertension, and left ventricular function. Results: Mean age was 70.8 years; 54.9% were male, 62.1% had hypertension. Arrhythmias occurred in 11.7% patients. The following results are significant (p < 0.05): Vascular territory: PVC burden showed no significant differences across vascular territories. PAC burden was higher in ACA strokes than MCA (12.5-fold). PAC burden was higher in MCA strokes than PCA (8.3-fold). Neuro-anatomical region: PVC burden was elevated in basal ganglia, cerebellum, and brainstem compared to frontal, temporal, parietal, and occipital lobes. PAC burden was lowest in frontal lobe, with incidence rate ratios (IRR) of 0.17 vs temporal, 0.03 vs basal ganglia, and 0.01 vs cerebellum. Frontal lobe had the lowest PACs. Hemisphere: PVC burden was higher in left-sided strokes compared to right (IRR=1.98) and bilateral strokes (IRR=12.33), and higher in right-sided strokes compared to bilateral strokes (IRR=6.22). PAC burden was higher in left- versus right-sided strokes (IRR 13.69) and lower in right- versus bilateral strokes (IRR 0.04). Stroke etiology: Ischemic and hemorrhagic strokes showed no difference in PVC or PAC burden. Conclusions: Ectopic activity post-stroke varies by lesion site, with higher burden in ACA territory, basal ganglia, and left hemisphere strokes. Anatomical stroke topography identities patients with a more urgent need for cardiac arrhythmia monitoring.