Background: Mechanical thrombectomy with stent retrievers in acute stroke has emerged as a promising new technique with the highest recanalization rate of the therapeutic procedures available so far. However, endovascular treatment is also associated with the risk of specific complications. One of those is the occurrence of peri-interventional subarachnoid hemorrhage (SAH), which has been reported in 5-16 % of the cases. Interestingly, this rate is higher than that of angiographically detectable perforations (0-3 %), leaving the majority of peri-interventional SAH to be due to angiographically occult perforations. Little is known about the influence of this finding on clinical outcome. The purpose of this study was to investigate the clinical relevance of SAH due to occult perforations during thrombectomy with stent retrievers.
Methods: Postinterventional computed tomography (CT) scans of 217 consecutive patients with acute occlusions of intracerebral arteries who were treated with stent retrievers in our department between October 2009 and October 2012 were retrospectively analyzed.
Results: SAH was found on postinterventional CT scans in 5.5 % of the cases. Seven cases were included for further analysis and matched to controls by the following characteristics: (1) site of occlusion, (2) result of the recanalization procedure according to the modified thrombolysis in cerebral infarction score, (3) administration of intravenous recombinant tissue plasminogen activator, (4) presence of proximal extracranial occlusion, (5) age, and (6) sex. Comparison of the angiographic data of the two cohorts showed no significant difference in the length of the procedures or the number of maneuvers needed for recanalization, nor were there significant differences in clinical outcomes as measured by NIHSS and mRS scores. Secondary symptomatic ICH occurred in one case in either cohort and led to death in both cases. The rate of asymptomatic ICH within the first 24 h after recanalization was significantly higher in the group with peri-interventional SAH (57 vs. 0 %, P = 0.018).
Conclusions: This small retrospective case-control study did not reveal a significant influence of peri-interventional SAH due to angiographically occult perforations on neurologic outcome of patients treated with stent retrievers.