Introduction Symptomatic intracerebral hemorrhage (sICH) is a devastating complication after endovascular thrombectomy. Prior reports have demonstrated that thrombolysis in cerebral infarction (TICI) ≥2 b reperfusion is protective against sICH. We aimed to further examine the relationship between reperfusion grade and sICH, to elucidate whether a difference between TICI 2b and 3 exists, and to determine whether this relationship holds true for patients undergoing delayed thrombectomy (6–24 hours).

Methods We performed a single-center retrospective review of prospectively-recorded data for patients undergoing endovascular thrombectomy for large vessel occlusion between January 2015 and February 2018. Multivariable logistic regression analyses were performed to identify predictors of parenchymal hematoma (PH) and sICH (NINDS—National Institute of Neurological Disorders and Stroke, SITS-MOST—Safe Implementation of Thrombolysis in Stroke Monitoring Study, ECASS III—European-Australian Cooperative Acute Stroke Study III criteria) and to identify the role of reperfusion grade. This analysis was repeated for delayed thrombectomy patients.

Results 528 patients were included; mean age was 71.5% and 43% were male. Median NIHSS (National Institutes of Health Stroke Scale) and time last seen well (TLSW) to treatment were 17 and 4.8 hours, respectively. Successful recanalization was achieved in 94%. On multivariable analyses, ASPECTS (Alberta Stroke Programme Early CT Score) was a predictor of PH (OR 0.7, 95% CI 0.57 to 0.87; p=0.002) for patients achieving any reperfusion grade. For patients achieving successful reperfusion, lower ASPECTS was a predictor of PH (OR 0.73, 95% CI 0.58 to 0.91; p=0.005) and of sICH (ECASS III) (OR 0.67, 95% CI 0.45 to 0.98; p=0.04); in addition, TICI 2b as compared with TICI 3 was a predictor of PH (OR 2.1, 95% CI 1 to 4.4; p=0.04) and of sICH (NINDS) (OR 7.5, 95% CI 1 to 57; p=0.045). TLSW to treatment was not an independent predictor of PH or sICH.

Conclusion Higher baseline ASPECTS and higher degree of reperfusion following endovascular thrombectomy is associated with reduced likelihood of PH and sICH.