Article Text
Abstract
Background and objective Hydrophilic polymer embolism (HPE) due to coated vascular devices is a recognized iatrogenic complication of endovascular therapies. This has been linked with significant sequelae, including neuroinflammation, acute ischemic stroke, cerebral hemorrhage and death. Despite this recognition, procedure and device-specific frequencies and clinical risks in cerebrovascular interventions are poorly investigated. We aim to evaluate the frequency of polymer coating delamination among stroke patients undergoing endovascular thrombectomy. Correlation between coating delamination and patient and procedural factors, including outcome, device type, number of passes and procedural duration are assessed.
Methods Retrospective analysis of consecutively retrieved thrombectomy specimen from acute large vessel stroke patients undergoing endovascular interventions. A total of 92 specimen were studied. H and E stained slides of the extracted thrombus were analyzed by a neuropathologist with extensive experience in histopathologic detection of HPE for the presence and dimensions of polymer foreign body within the extracted thrombus specimens. Foreign body chemical analysis was performed. Prospectively collected data including patient demographics, stroke severity, procedural details and outcomes were correlated with the presence or absence of polymer.
Results In 92 cerebral thrombectomy specimens, 30 revealed evidence of polymer delamination. Deposited polymer appeared as basophilic nonrefractile coiled foreign bodies on histopathology. Procedural details revealed heterogenous patterns of device use. No correlation between polymer delamination and use of a specific thrombectomy device such as stent retriever, aspiration catheters or guide catheters was found. Presence of polymer was not associated with clinical outcomes as measured by the modified Rankin score (mRS). However our study is not powered to detect this difference and 90 day outcomes based on mRS may not be the best outcome endpoint to detect delayed consequences of intracerebral polymer deposition. There was a trend of increased polymer presence with longer procedure times and polymer delamination was twice as common when the number of passes was greater than 1 compared to cases that used a single pass.
Conclusion This study is the first to evaluate the frequency of polymer coating delamination during thrombectomy procedures. Polymer coating particulates were observed in 33% of patients. Although correlation with patient outcome was not established in this study, limited sample size, heterogeneous device combinations, retrospective nature and lack of long term follow up limits interpretation. In light of previously documented adverse effects of coating embolism, our findings indicate the need for large-scale long-term prospective studies to assess device risks.
Disclosures R. Mehta: None. R. Mehta: None. J. Vos: None. A. Rai: 2; C; Stryker Neurovascular.