Abstract
Objective: The aim was to determine the frequency of and contributing factors related to subarachnoid hemorrhage (SAH) after mechanical thrombectomy using the MERCI retriever in acute ischemic stroke patients.
Methods: Data collected from the records of acute ischemic stroke patients treated within an 8-hour time window by an intracranial endovascular revascularization technique involving the use of the MERCI retriever were analyzed retrospectively.
Results: Twenty-three consecutive acute ischemic stroke patients with intracranial major-vessel occlusion were treated at our department between April 2009 and February 2012. The MERCI retriever was used in 12 patients (52.2%). There was a non-significant trend for increasing SAH in the MERCI group compared with the non-MERCI group (5 of 12 patients, 41.7% vs. 1 of 11 patients, 9.1%, p=0.155). There were no symptomatic intracranial hemorrhages. The total number of passes of the MERCI retriever through the occluded vessel was significantly greater in the SAH subgroup than in the non-SAH subgroup (average 3.6 vs. 1.6 times, p=0.038).
Conclusion: SAH after mechanical thrombectomy using the MERCI retriever was associated with the total number of passes through the occluded vessel. The absence of symptomatic intracranial hemorrhages in this study implies that the use of the MERCI retriever in endovascular therapy is safe. However, to ensure the safety of MERCI retriever use in endovascular therapy, the number of passes might have to be limited to 2 or 3 times.
