title: Magnetic Resonance Imaging Plaque Hemorrhage for Risk Stratification in Carotid Artery Disease With Moderate Risk Under Current Medical Therapy.
abstract: Magnetic resonance imaging (MRI)-defined carotid plaque hemorrhage (MRIPH) can predict recurrent cerebrovascular ischemic events in severe symptomatic carotid stenosis. It is less clear whether MRIPH can improve risk stratification despite optimized medical secondary prevention in those with moderate risk.
  
  
  
  One-hundred fifty-one symptomatic patients with 30% to 99% carotid artery stenosis (median age: 77, 60.5% men) clinically deemed to not benefit from endarterectomy were prospectively recruited to undergo MRI and clinical follow-up (mean, 22 months). The clinical carotid artery risk score could be evaluated in 88 patients. MRIPH+ve was defined as plaque intensity >150% that of adjacent muscle. Survival analyses were performed with recurrent infarction (stroke or diffusion-positive cerebral ischemia) as the main end point.
  
  
  
  Fifty-five participants showed MRIPH+ve; 47 had low, 36 intermediate, and 5 high carotid artery risk scores. Cox regression showed MRIPH as a strong predictor of future infarction (hazard ratio, 5.2; 95% confidence interval, 1.64-16.34;P=0.005, corrected for degree of stenosis), also in the subgroup with 50% to 69% stenosis (hazard ratio, 4.1; 95% confidence interval, 1-16.8;P=0.049). The absolute risk of future infarction was 31.7% at 3 years in MRIPH+ve versus 1.8% in patients without (P<0.002). MRIPH increased cumulative risk difference of future infarction by 47.1% at 3 years in those with intermediate carotid artery risk score (P=0.004).
  
  
  
  The study confirms MRIPH to be a powerful risk marker in symptomatic carotid stenosis with added value over current risk scores. For patients undergoing current secondary prevention medication with clinically uncertain benefit from recanalization, that is, those with moderate degree stenosis and intermediate carotid artery risk scores, MRIPH offers additional risk stratification.
authors.affiliation: From the Radiological Sciences, Division of Clinical Neuroscience (A.A.H., R.J.S., N.A., D.P.A.); Stroke Trials Unit, Division of Clinical Neuroscience (P.M.B.), University of Nottingham, United Kingdom; and Department of Vascular Surgery, Nottingham University Hospital NHS Trust, United Kingdom (R.J.S., N.A., S.T.M.).
authors.forename: Akram A
authors.initials: AA
authors.lastname: Hosseini
authors.affiliation: From the Radiological Sciences, Division of Clinical Neuroscience (A.A.H., R.J.S., N.A., D.P.A.); Stroke Trials Unit, Division of Clinical Neuroscience (P.M.B.), University of Nottingham, United Kingdom; and Department of Vascular Surgery, Nottingham University Hospital NHS Trust, United Kingdom (R.J.S., N.A., S.T.M.).
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Simpson
authors.affiliation: From the Radiological Sciences, Division of Clinical Neuroscience (A.A.H., R.J.S., N.A., D.P.A.); Stroke Trials Unit, Division of Clinical Neuroscience (P.M.B.), University of Nottingham, United Kingdom; and Department of Vascular Surgery, Nottingham University Hospital NHS Trust, United Kingdom (R.J.S., N.A., S.T.M.).
authors.forename: Nishath
authors.initials: N
authors.lastname: Altaf
authors.affiliation: From the Radiological Sciences, Division of Clinical Neuroscience (A.A.H., R.J.S., N.A., D.P.A.); Stroke Trials Unit, Division of Clinical Neuroscience (P.M.B.), University of Nottingham, United Kingdom; and Department of Vascular Surgery, Nottingham University Hospital NHS Trust, United Kingdom (R.J.S., N.A., S.T.M.).
authors.forename: Philip M
authors.initials: PM
authors.lastname: Bath
authors.affiliation: From the Radiological Sciences, Division of Clinical Neuroscience (A.A.H., R.J.S., N.A., D.P.A.); Stroke Trials Unit, Division of Clinical Neuroscience (P.M.B.), University of Nottingham, United Kingdom; and Department of Vascular Surgery, Nottingham University Hospital NHS Trust, United Kingdom (R.J.S., N.A., S.T.M.).
authors.forename: Shane T
authors.initials: ST
authors.lastname: MacSweeney
authors.affiliation: From the Radiological Sciences, Division of Clinical Neuroscience (A.A.H., R.J.S., N.A., D.P.A.); Stroke Trials Unit, Division of Clinical Neuroscience (P.M.B.), University of Nottingham, United Kingdom; and Department of Vascular Surgery, Nottingham University Hospital NHS Trust, United Kingdom (R.J.S., N.A., S.T.M.). dorothee.auer@nottingham.ac.uk.
authors.forename: Dorothee P
authors.initials: DP
authors.lastname: Auer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000209:etiology; D002340:Carotid Artery Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D016894:Endarterectomy, Carotid / Q000379:methods; D005260:Female; D006470:Hemorrhage / Q000000981:diagnostic imaging / Q000209:etiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000150:complications / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000209:etiology
keywords: atherosclerotic plaque; carotid stenosis; cerebral infarction; endarterectomy; magnetic resonance imaging; stroke