title: Femoral plaque echogenicity and cardiovascular risk in claudicants.
abstract: OBJECTIVE
  The present study was designed to verify whether the evaluation of femoral plaque echogenicity might be a useful tool for cardiovascular risk assessment in patients affected by lower extremity peripheral arterial disease.
  
  
  BACKGROUND
  Lower extremity peripheral arterial disease is a common manifestation of atherosclerosis and is associated with a high risk of developing major cardiovascular events. Vulnerable atherosclerotic plaque plays a central role in the occurrence of acute ischemic events in different vascular territories. Furthermore, atherosclerosis is a systemic disease, and the presence of an unstable atherosclerotic plaque in a certain vascular district, characterized by low echogenicity at B-mode ultrasound, is associated to a greater prevalence of unstable plaques in other vascular beds.
  
  
  METHODS
  Femoral plaque echogenicity of 246 claudicants with ankle/brachial index ≤0.90 was evaluated at B-mode ultrasound by visual analysis and by calculating the grayscale median (GSM) value. In these patients, the occurrence of myocardial infarction and stroke was prospectively assessed.
  
  
  RESULTS
  Femoral GSM values and plaque types assessed by visual analysis were highly correlated by Spearman analysis (rho = 0.905, p < 0.001). During a median follow-up of 30 months, 32 patients (13%) had a major cardiovascular event. Compared with patients without events, those who experienced an event during the follow-up had a lower femoral plaque GSM value (42.9 ± 26.2 vs. 58.8 ± 19.3, p = 0.002) and a higher prevalence of hypoechoic femoral plaque at visual analysis (68.8% vs. 19.6%, p < 0.001). At Cox analysis, femoral GSM showed an inverse relationship with cardiovascular risk, even after adjustment for possible confounders (hazard ratio: 0.96, 95% confidence interval [CI]: 0.95 to 0.98, p < 0.001). Furthermore, patients with hypoechoic femoral plaques at visual analysis had a 7.24-fold increased cardiovascular risk compared with patients with hyperechoic plaques after adjustment for possible confounders (95% CI: 3.23 to 16.22, p < 0.001).
  
  
  CONCLUSIONS
  This study demonstrates that the presence of hypoechoic atherosclerotic femoral plaques is associated with higher cardiovascular risk in lower extremity peripheral arterial disease patients.
authors.affiliation: Division of Cardiology, Department of Clinical Medicine, Cardiovascular and Immunological Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Vittorio
authors.initials: V
authors.lastname: Schiano
authors.forename: Giusy
authors.initials: G
authors.lastname: Sirico
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Giugliano
authors.forename: Eugenio
authors.initials: E
authors.lastname: Laurenzano
authors.forename: Linda
authors.initials: L
authors.lastname: Brevetti
authors.forename: Cinzia
authors.initials: C
authors.lastname: Perrino
authors.forename: Gregorio
authors.initials: G
authors.lastname: Brevetti
authors.forename: Giovanni
authors.initials: G
authors.lastname: Esposito
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000453:epidemiology; D005260:Female; D005263:Femoral Artery / Q000000981:diagnostic imaging*; D005500:Follow-Up Studies; D006801:Humans; D007383:Intermittent Claudication / Q000150:complications / Q000000981:diagnostic imaging / Q000453:epidemiology*; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology* / Q000209:etiology; D058226:Plaque, Atherosclerotic / Q000150:complications / Q000000981:diagnostic imaging* / Q000453:epidemiology; D015995:Prevalence; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D014463:Ultrasonography