Abstract
OBJECTIVE: After endovascular treatment (EVT) for ischemic stroke (IS), clinical observations have shown that some patients with small infarct volumes develop hemorrhagic transformation (HT), while some patients with large infarct volumes do not. This study aims to analyze the factors contributing to these differences and to assess the impact of HT on neurological outcomes. METHODS: A total of 732 patients were divided into small infarct volume (0-15 mL) and large infarct volume (≥70 mL) groups. The incidence of HT, risk factors, neurological outcomes (NIHSS changes), early neurological deterioration (END), and 7- and 90-day mortality rates were compared. RESULTS: In patients with small infarcts, higher systolic blood pressure, lower triglyceride levels, the number of EVTs, and other factors were related to an increased risk of HT. By contrast, in those with large infarcts, where HT occurred more frequently and was more severe, it was associated with more severe neurological deficits before treatment, elevated albumin levels, and the number of EVTs. PH2 hemorrhage was linked to more severe neurological deficits, higher END rates, and increased short- and long-term mortality, particularly in large infarcts. CONCLUSION: Infarct volume is closely related to the occurrence and severity of HT. HT in small infarcts is influenced by hemodynamic and metabolic factors, while in large infarcts, it is linked to extensive brain tissue damage. PH2 hemorrhage is the most adverse prognostic subtype, highlighting the need for careful monitoring and intervention in patients with large infarcts.