title: Outcome of carotid endarterectomy and stent insertion based on grading of carotid endarterectomy risk: a 7-year prospective study.
abstract: OBJECTIVE
  The authors of this study prospectively compared periprocedural neurological morbidity and the appearance of lesions on diffusion-weighted (DW) magnetic resonance (MR) imaging in patients who had undergone carotid endarterectomy (CEA) or carotid artery stent placement (CASP) with distal balloon protection, based on a CEA risk grading scale.
  
  
  METHODS
  Patients undergoing CEA (139 patients) and CASP (92 patients) were classified into Grades I to IV, based on the presence of angiographic (Grade II), medical (Grade III), and neurological (Grade IV) risks. Although not randomized, the CEA and CASP groups were well matched in terms of the graded risk factors except for a greater proportion of neurologically unstable patients in the CEA group (11 compared with 3%, p = 0.037). There were greater proportions of asymptomatic (64 compared with 34%, p = 0.006) and North American Symptomatic Carotid Endarterectomy Trial-ineligible patients (29 compared with 14%, p < 0.0001) in the CASP group. The overall rates of neurological morbidity with ischemic origin and the appearance of lesions on DW MR imaging after CEA were 2.2 and 9.3%, and those after CASP were 7.6 and 35.9% (nondisabling stroke only), respectively. The only disabling stroke was caused by an intracerebral hemorrhage attributable to hyperperfusion in one case (0.7%) of CEA. There were no deaths. There was no significant association between neurological morbidity and the risk grade in patients who had undergone CEA, although the incidence of lesions on DW imaging was significantly greater in the Grade IV risk group compared with that in the other risk groups combined (42.1 compared with 4.2%, p < 0.0001). After CASP, a higher incidence of neurological morbidity and lesions on DW imaging was noted for the Grade II and III risk groups combined as compared with that in the Grade I risk group, regardless of a symptomatic or an asymptomatic presentation (neurological morbidity: 10.5 compared with 3.1%, respectively, p = 0.41; and DW imaging lesions: 47.4 compared with 19.4%, p = 0.01). The incidence of lesions on DW imaging after CEA was significantly lower than that after CASP except for the Grade IV risk groups.
  
  
  CONCLUSIONS
  Despite a higher incidence of DW imaging-demonstrated lesions in the Grade IV risk group, there was no significant association between the risk group and neurological morbidity rates after CEA. The presence of vascular and medical risk profiles conferred higher rates of neurological morbidity and an increased incidence of lesions on DW imaging after CASP. Considering that no serious nonneurological complications were noted, CEA and CASP appear to be complementary methods of revascularization for carotid artery stenosis with various risk profiles.
authors.affiliation: Department of Neurosurgery, National Cardiovascular Center, Suita, Osaka, Japan. kiihara@hsp.ncvc.go.jp
authors.forename: Koji
authors.initials: K
authors.lastname: Iihara
authors.forename: Kenichi
authors.initials: K
authors.lastname: Murao
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Sakai
authors.forename: Naoaki
authors.initials: N
authors.lastname: Yamada
authors.forename: Izumi
authors.initials: I
authors.lastname: Nagata
authors.forename: Susumu
authors.initials: S
authors.lastname: Miyamoto
mesh_terms: D000368:Aged; D001925:Brain Damage, Chronic / Q000175:diagnosis; D016893:Carotid Stenosis / Q000601:surgery*; D002404:Catheterization; D002543:Cerebral Hemorrhage / Q000175:diagnosis; D002544:Cerebral Infarction / Q000175:diagnosis*; D038524:Diffusion Magnetic Resonance Imaging; D016894:Endarterectomy, Carotid; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D010043:Outcome and Process Assessment, Health Care; D011183:Postoperative Complications / Q000175:diagnosis*; D011446:Prospective Studies; D012307:Risk Factors; D015607:Stents