2026 American Academy of Neurology Abstract Website

Objective:

To assess differences in mechanical thrombectomy outcomes among distinct embolic stroke etiology

Background:

Mechanical thrombectomy (MT) is the standard treatment for large-vessel occlusion stroke, but outcomes may differ by embolic source. Evidence for MT in non-cardioembolic embolic strokes—including septic embolism, neoplastic/hypercoagulable, and paradoxical venous embolism —remains limited to small series. These atypical etiologies present distinct challenges.

Design/Methods:

Using the 2022 National Inpatient Sample, we conducted a retrospective analysis of hospitalizations for acute ischemic stroke treated with mechanical thrombectomy only , identified using ICD-10 procedure codes. Discharges were categorized by embolic source: cardioembolic, septic-embolism, neoplastic or hypercoagulable embolism, and paradoxical venous embolism, using validated ICD-10 definitions. Survey weights were applied to generate national estimates. Demographics, illness severity, resource utilization, and in-hospital outcomes were compared across etiologic groups, with cardioembolic stroke serving as the reference cohort.

Results:

Cardioembolic stroke predominated among MT-treated admissions. Compared with cardioembolic cases (76 [67–84] years), septic embolism (SE) (60 [44–70]), neoplastic/hypercoagulable (65 [56–70]), and venous embolism (56 [45–69]) patients were younger (p<0.001). SE showed greater illness severity (extreme loss 91.5% vs 41.9%, p<0.001), longer hospitalization (14 [8–27] vs 7 [4–12] days, p<0.001), and higher mortality (19.2% vs 11.8%, p=0.04). Discharge to home was lower across non-cardioembolic groups—SE 7.2%, neoplastic/hypercoagulable 9.0%, and venous 27.0%—compared with cardioembolic 18.8% (p=0.008). Hospital charges were highest for SE ($317K) and neoplastic/hypercoagulable ($316K) compared with cardioembolic ($173K, p<0.001). Complications such as sepsis, PEG placement, and DVT were more frequent in non-cardioembolic groups, whereas herniation and hemorrhagic transformation were more frequent in cardioembolic group.

Conclusions:

Compared with cardioembolic stroke, septic, neoplastic, and venous embolic etiologies had worse outcomes following mechanical thrombectomy, including higher illness severity, mortality, complications, and resource utilization. Septic embolism showed the poorest prognosis, and neoplastic emboli had the highest cost burden. These results underscore the need for further research into cautious, etiology-specific patient selection and management.