Association of antithrombotic therapy with postoperative rebleeding in patients with cerebral amyloid angiopathy.

Background: Cerebral amyloid angiopathy is a common cause of subcortical hemorrhage in older adults. Although open hematoma removal may be performed for severe subcortical hemorrhage, its safety in patients with cerebral amyloid angiopathy has not been established, and postoperative rebleeding may occur. Therefore, this study aimed to investigate factors associated with postoperative rebleeding.

Methods: Out of 145 consecutive patients who had undergone craniotomy for surgical removal of subcortical intracerebral hemorrhage between April 2010 and August 2019 at a single institution in Japan, we examined 109 patients with subcortical hemorrhage who met the inclusion criteria. After excluding 30 patients whose tissue samples were unsuitable for the study, the final study cohort comprised 79 patients.

Results: Of the 79 patients, 50 (63%) were diagnosed with cerebral amyloid angiopathy (cerebral amyloid angiopathy group) and 29 (37%) were not diagnosed with noncerebral amyloid angiopathy (noncerebral amyloid angiopathy group). Postoperative rebleeding occurred in 12 patients (24%) in the cerebral amyloid angiopathy group and in 2 patients (7%) in the noncerebral amyloid angiopathy group. Preoperative prothrombin time-international normalized ratio and intraoperative bleeding volume were significantly associated with postoperative rebleeding in the cerebral amyloid angiopathy group (odds ratio = 42.4, 95% confidence interval = 1.14-1578; p = 0.042 and odds ratio = 1.005, 95% confidence interval = 1.001-1.008; p = 0.007, respectively).

Conclusions: Patients with cerebral amyloid angiopathy-related cerebral hemorrhage who are receiving antithrombotic therapy, particularly warfarin therapy, are at a high risk of postoperative rebleeding.

Trial registration: Registry and Registration Number of the study: 19-220, 2019/12/23, retrospectively registered.