Original contributionPolymer-induced central nervous system complications following vascular procedures: spectrum of iatrogenic injuries and review of outcomes☆,☆☆,★
Introduction
Polymers are commonly used as surface coatings on endovascular catheters and vascular devices. Their use on sheaths, catheters, microcatheters, and guidewires, among other vascular devices, allows for less invasive therapeutic approaches and has facilitated novel endovascular techniques. These coating materials enhance device lubrication, maneuverability, and biocompatibility and facilitate access of small vessels while reducing vascular spasm [1]. Polymer-coated aneurysm coils have additionally been shown to improve volumetric occlusion and facilitate early inflammation and thrombus organization within cerebral aneurysms [2], [3]. With evolving nanotechnologies and increased use of insertable and implantable vascular devices, applications of these coating materials are expected to increase.
Despite their advantages, polymer coatings have the potential to induce significant adverse reactions. Chemical injuries and unanticipated dissociation of polymer particles from vascular device surfaces have been increasingly recognized following routine use in patients [4], [5], [6], [7], [8]. These phenomena have been associated with diverse outcomes that depend on organ and site of involvement. In 2009, we reported to the US Food and Drug Administration the first fatal case of polymer embolism, which involved the brain [6]. In spite of limited recognition and reporting of this complication, multiple cases over recent years provide additional evidence that morbidity and mortality associated with these iatrogenic phenomena are underrecognized [5], [6], [7], [8], [9], [10], [11], [12], [13], [14]. Further characterization of polymer reactions, including organ-specific effects, and identification of etiologic factors are therefore warranted and have potential to improve the safety of new and emerging vascular technologies.
Sensitive methods of earlier detection are needed to elucidate the true clinical incidence and significance of polymer phenomena. In this study, we review the spectrum of clinical, neuroradiologic, and neuropathologic findings and summarize premortem diagnostic features and outcomes of polymer complications involving the central nervous system. This review is performed with the intent to clarify the nature of clinical risks posed to patients; facilitate earlier diagnosis of polymer reactions by radiologists and pathologists; summarize available preventative and therapeutic strategies for treating physicians; and highlight areas of needed improvement to manufacturers, biomedical engineers, polymer chemists, and regulatory agencies.
Section snippets
Materials and methods
This study was performed under exemption from the institutional review board and in accordance with the ethical standards of institutional and national research committees. Published reports, dating from 1997 to 2015, of intracranial polymer reactions due to routine catheterization and/or endovascular procedures were identified using PubMed. Cases previously reported by our group were systematically reanalyzed. Our archives were also searched for additional unreported consult cases. Patients in
Results
Thirty-two patients with documented intracranial polymer reactions and available pathology or CSF laboratory data were identified (age range, 36-87 years). Patients had undergone various procedures, including cerebral angiogram (94%), endovascular aneurysm coil embolization (50%), aneurysm flow diversion (25%), intraarterial thrombolysis (9%), mechanical thrombectomy (6%), peripherally inserted central catheter placement (3%), cardiac catheterization (3%), central venous catheterization (3%),
Discussion
Polymeric substances are widely used as coatings on endovascular catheters and vascular devices. Their unique properties enhance lubrication and biocompatibility of device surfaces and have enabled several innovative endovascular technologies. Nonetheless, complications associated with their use have increasingly been recognized. Early reports documented shedding of polymer coats from device surfaces upon percutaneous vascular insertion and illustrated potential for significant inflammatory
Conclusion
Polymer coatings have played an important role in the evolution of endovascular technologies and are used in millions of clinical procedures performed worldwide each year. Despite their utility, a variety of adverse effects related to their use have been recognized and reported. Herein, we review the spectrum of cerebral injuries that result from unanticipated polymer-induced complications in the acute, subacute, and delayed postprocedure clinical settings. Unexpected outcomes include death,
References (22)
- et al.
Stenting in acute coronary syndromes: a comparison of radial versus femoral access sites
J Am Coll Cardiol
(1998) - et al.
Intravascular polymer material following coil embolization of a giant cerebral aneurysm
Hum Pathol
(2009) - et al.
Hydrophilic polymer emboli: an under-recognized iatrogenic cause of ischemia and infarct
Mod Pathol
(2010) - et al.
Hydrophilic polymer embolism: an underrecognized iatrogenic cause of ischemia, inflammation, and coagulopathy
Hum Pathol
(2015) - et al.
Abnormal white matter changes after cerebral aneurysm treatment with polyglycolic-polylactic acid coils
World Neurosurg
(2010) - et al.
Hydrophilic polymer embolism and associated vasculopathy of the lung: prevalence in a retrospective autopsy study
Hum Pathol
(2015) - et al.
Microembolism after endovascular treatment of unruptured cerebral aneurysms: reduction of its incidence by microcatheter lumen aspiration
Neurointervention
(2014) - et al.
Matrix and bioabsorbable polymeric coils accelerate healing of intracranial aneurysms: long-term experimental study
Stroke
(2003) - et al.
Embolization of intracranial aneurysms with hydrogel-coated coils versus inert platinum coils: effects on packing density, coil length and quantity, procedure performance, cost, length of hospital stay and durability of therapy
Stroke
(2006) - et al.
Foreign bodies in small arteries after use of an infusión microcatheter
Am J Neuroradiol
(1997)
Hydrophilic polymer embolism and associated vasculopathy of the brain (abstract)
J Neuropathol Exp Neurol
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2018, Cardiovascular PathologyCitation Excerpt :In no way does this exclude other potential causes. There are well-documented cases of systemic embolization (brain vasculature included) of the hydrophilic polymer that is widely used as a surface coating on vascular medical devices [19,20]. Not to mention, the potential of tumor fragments to form cellular emboli in cerebral or other systemic vessels may originate in the intracardial tumors including benign myxoma or fibroelastoma [21–25].
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Competing interests: none.
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Funding/Support: This work was supported by the New York State/United University Professions Joint Labor-Management Committees to R. I. M. R. I. M. is also supported by a grant from the National Institute of Neurological Disorders and Stroke (K08NS089830).
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This work was presented, in part, at the 89th annual meeting of the American Association of Neuropathologists (Charleston, SC) on June 22, 2013, and in part at the 52nd annual meeting of the American Society of Neuroadiology (Montreal, Canada) on May 22, 2014.