title: Very late ischemic complications in flow-diverter stents: a retrospective analysis of a single-center series.
abstract: OBJECTIVE The authors evaluate the rate and discuss the pathomechanisms of very late (≥ 4-month) ischemic complications after flow-diverter stent (FDS) placement for intracranial aneurysms. METHODS The authors retrospectively reviewed the clinical data of the patients treated at Pitié-Salpêtrière Hospital between January 2010 and September 2014, who underwent FDS placement for intracranial aneurysm. The patients received dual-antiplatelet therapy (clopidogrel and aspirin) 5 days before and 3-6 months after the procedure and then aspirin alone for 6-9 months. An ischemic complication was defined as a sudden focal neurological deficit documented on diffusion-weighted images. RESULTS Eighty-six consecutive patients were included. Three (3.5%) patients treated with the Pipeline embolization device experienced a delayed acute ischemic stroke (2 cases of perforator/side-wall branch infarction and 1 case of thromboembolic stroke) with an average delay of 384 days (4 months, 20 months, and 13 months, respectively). The aneurysm locations were the left superior cerebellar artery, the right anterior choroid artery, and the left internal carotid artery (paraclinoid segment), respectively. The complications occurred after the patients had completed the antiaggregation protocol, except for Patient 1, who was receiving aspirin alone because of a spontaneous hematoma. At the acute phase, no in-stent thromboses were found on digital subtraction angiography. In Patient 2, the treated anterior choroid artery was occluded 20 months after the procedure. In Patient 3, a focal stenosis (approximately 40%) of the distal aspect of the FDS, probably caused by intimal hyperplasia, was seen. CONCLUSIONS Very late ischemic complications after FDS treatment were observed in 3.5% of the cases in the authors' series, some of which occurred as late as more than 1 year after placement.
authors.affiliation: Departments of 1 Interventional Neuroradiology.
authors.forename: Alexis
authors.initials: A
authors.lastname: Guédon
authors.affiliation: Departments of 1 Interventional Neuroradiology.|Paris VI University, Pierre et Marie Curie, Paris; and.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Clarençon
authors.affiliation: Departments of 1 Interventional Neuroradiology.
authors.forename: Federico
authors.initials: F
authors.lastname: Di Maria
authors.affiliation: Vascular Neurology, and.|Paris VI University, Pierre et Marie Curie, Paris; and.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Rosso
authors.affiliation: Department of Neuroradiology and Endovascular Therapy, Jean Minjoz University Hospital, Franche Comté University School of Medecine, Besançon, France.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Biondi
authors.affiliation: Departments of 1 Interventional Neuroradiology.|Paris VI University, Pierre et Marie Curie, Paris; and.
authors.forename: Joseph
authors.initials: J
authors.lastname: Gabrieli
authors.affiliation: Neuro-anesthesiology, Pitié-Salpêtrière Hospital.
authors.forename: Patricia
authors.initials: P
authors.lastname: Rojas
authors.affiliation: Departments of 1 Interventional Neuroradiology.|Paris VI University, Pierre et Marie Curie, Paris; and.
authors.forename: Jacques
authors.initials: J
authors.lastname: Chiras
authors.affiliation: Departments of 1 Interventional Neuroradiology.
authors.forename: Nader
authors.initials: N
authors.lastname: Sourour
mesh_terms: D000328:Adult; D002545:Brain Ischemia / Q000209:etiology*; D004621:Embolization, Therapeutic / Q000295:instrumentation; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology*; D012189:Retrospective Studies; D015607:Stents / Q000009:adverse effects*; D020521:Stroke / Q000209:etiology*; D013997:Time Factors
keywords: AChA = anterior choroid artery; DIPH = delayed ipsilateral parenchymal hemorrhage; DSA = digital subtraction angiography; DWI = diffusion-weighted imaging; FDS = flow-diverter stent; IQR = interquartile range; NIHSS = NIH Stroke Scale; PED = Pipeline embolization device; Pipeline embolization device; SCA = superior cerebellar artery; delayed complication; flow-diverter stent; mRS = modified Rankin Scale; stroke; vascular disorders