title: Plaque Composition in the Proximal Superficial Femoral Artery and Peripheral Artery Disease Events.
abstract: The aim of this study was to describe associations of the presence of lipid-rich necrotic core (LRNC) in the proximal superficial femoral artery (SFA) with lower extremity peripheral artery disease (PAD) event rates and systemic cardiovascular event rates.
  
  
  
  LRNC in the coronary and carotid arteries is associated with adverse outcomes but has not been studied previously in lower extremity arteries.
  
  
  
  Participants with ankle-brachial index (ABI) values <1.00 were identified from Chicago medical centers and followed annually. Magnetic resonance imaging was used to characterize SFA atherosclerotic plaque at baseline. Medical records for hospitalizations and procedures after baseline were adjudicated for lower extremity revascularization, amputation, and critical limb ischemia and also for new coronary events, ischemic stroke, and mortality.
  
  
  
  Of 254 participants with PAD, 62 (24%) had LRNC and 149 (59%) had calcium in the SFA at baseline. Cox regression analyses were adjusted for age, sex, race, comorbidities, baseline ABI, and other confounders. SFA LRNC was associated with an increased incidence of the combined outcome of lower extremity amputation, critical limb ischemia, ABI decline >0.15, and revascularization at 47-month follow-up (hazard ratio: 2.18; 95% confidence interval: 1.27 to 3.75; p = 0.005). The association of SFA LRNC with PAD events was maintained even when this combined outcome excluded lower extremity revascularization (hazard ratio: 2.58; 95% confidence interval: 1.25 to 5.33; p = 0.01). LRNC in the SFA was not associated with all-cause mortality, acute coronary events, or stroke.
  
  
  
  Among patients with PAD, LRNC in the SFA was associated with higher rates of clinical PAD events, and this association was independent of ABI. Further study is needed to determine whether interventions that reduce SFA LRNC prevent PAD events.
authors.affiliation: Department of Medicine Northwestern University Feinberg School of Medicine, Chicago, Illinois; Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois. Electronic address: mdm608@northwestern.edu.
authors.forename: Mary M
authors.initials: MM
authors.lastname: McDermott
authors.affiliation: Departments of Medicine, Radiology, and Medical Imaging, University of Virginia Health System, Charlottesville, Virginia.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Kramer
authors.affiliation: Department of Health Research and Policy, Stanford University School of Medicine, Stanford, California.
authors.forename: Lu
authors.initials: L
authors.lastname: Tian
authors.affiliation: Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
authors.forename: James
authors.initials: J
authors.lastname: Carr
authors.affiliation: Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Jack M
authors.initials: JM
authors.lastname: Guralnik
authors.affiliation: Department of Medicine, University of Chicago, Chicago, Illinois.
authors.forename: Tamar
authors.initials: T
authors.lastname: Polonsky
authors.affiliation: Department of Radiology, University of Chicago, Chicago, Illinois.
authors.forename: Timothy
authors.initials: T
authors.lastname: Carroll
authors.affiliation: Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; Division of Vascular Surgery, Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
authors.forename: Melina
authors.initials: M
authors.lastname: Kibbe
authors.affiliation: National Institute on Aging, Bethesda, Maryland.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Criqui
authors.affiliation: Department of Family and Preventive Medicine, University of California, San Diego, San Diego, California.
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.affiliation: Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
authors.forename: Lihui
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Department of Radiology and Bioengineering, University of Washington, Seattle, Washington.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Hippe
authors.affiliation: Department of Medicine Northwestern University Feinberg School of Medicine, Chicago, Illinois; Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
authors.forename: John
authors.initials: J
authors.lastname: Wilkins
authors.affiliation: Department of Radiology and Bioengineering, University of Washington, Seattle, Washington.
authors.forename: Dongxiang
authors.initials: D
authors.lastname: Xu
authors.affiliation: Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
authors.forename: Yihua
authors.initials: Y
authors.lastname: Liao
authors.affiliation: University Cardiovascular Surgeons, Rush University Medical Center, Chicago, Illinois.
authors.forename: Walter
authors.initials: W
authors.lastname: McCarthy
authors.affiliation: Department of Radiology and Bioengineering, University of Washington, Seattle, Washington.
authors.forename: Chun
authors.initials: C
authors.lastname: Yuan
mesh_terms: D054058:Acute Coronary Syndrome / Q000453:epidemiology; D000368:Aged; D000671:Amputation, Surgical; D055109:Ankle Brachial Index; D002641:Chicago / Q000453:epidemiology; D015897:Comorbidity; D016638:Critical Illness; D005260:Female; D005263:Femoral Artery / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D005355:Fibrosis; D006801:Humans; D007511:Ischemia / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D053208:Kaplan-Meier Estimate; D008055:Lipids / Q000032:analysis*; D008137:Longitudinal Studies; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D058729:Peripheral Arterial Disease / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D058226:Plaque, Atherosclerotic; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology; D013997:Time Factors; D016896:Treatment Outcome; D061205:Vascular Calcification / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D014656:Vascular Surgical Procedures
chemical_list: D008055:Lipids
keywords: MRI; femoral artery; lipid rich necrotic core; vascular medicine