title: Clinical predictors of left atrial thrombus and spontaneous echocardiographic contrast in patients with atrial fibrillation.
abstract: OBJECTIVE
  We sought to determine the relationship between clinical risk factors for systemic thromboembolism in patients with atrial fibrillation and the prevalence of left atrial (LA) spontaneous echocontrast (SEC) and LA thrombus (LAT).
  
  
  BACKGROUND
  Atrial fibrillation is associated with an increased risk of systemic thromboembolism. LA SEC and LAT also predict thromboembolic events. The relationship between clinical risk factors for systemic thromboembolism and prevalence of LA SEC and LAT is unknown.
  
  
  METHODS
  In all, 524 patients with atrial fibrillation underwent transesophageal echocardiography between August 2000 and March 2005. Clinical risk factors for systemic thromboembolism were determined for each patient. A CHADS(2) score ranging from 0 to 6 was calculated for each patient as: congestive heart failure = 1 point; hypertension = 1 point; age 75 years or older = 1 point; diabetes mellitus = 1 point; and history of stroke including transient ischemic attack or systemic embolism = 2 points. Transesophageal echocardiography reports were reviewed for the presence of LA SEC and LAT. Univariate and multivariable models were structured to assess which clinical risk factors predicted the presence of LA SEC or LAT.
  
  
  RESULTS
  In a multivariable model, age 75 years or older, previous thromboembolic event, and left ventricular ejection fraction (LVEF) less than 40% predicted LA SEC, whereas LVEF less than 40% was the only predictor of LAT. LA SEC was present in 24% of patients with a CHADS(2) score of 0, but was present in 58% with a CHADS(2) score of 5 or 6 (P < .0001). LAT was present in 3% percent of patients with a CHADS(2) score of 0, but in 17% of patients with a CHADS(2) score of 5 or 6 (P = .0026).
  
  
  CONCLUSIONS
  Age 75 years or older, previous thromboembolic event, and LVEF less than 40% predict presence of LA SEC. LVEF less than 40% is the only multivariate predictor of LAT. The prevalence of LA SEC and LAT increases with increasing CHADS(2) score.
authors.affiliation: Mid America Heart Institute, Kansas City, Missouri, USA.
authors.forename: Valerie J
authors.initials: VJ
authors.lastname: Rader
authors.forename: Taiyeb M
authors.initials: TM
authors.lastname: Khumri
authors.forename: Madhuri
authors.initials: M
authors.lastname: Idupulapati
authors.forename: Casey N
authors.initials: CN
authors.lastname: Stoner
authors.forename: Anthony
authors.initials: A
authors.lastname: Magalski
authors.forename: Michael L
authors.initials: ML
authors.lastname: Main
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D018618:Echocardiography, Doppler, Color / Q000379:methods; D017548:Echocardiography, Transesophageal / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria; D006331:Heart Diseases / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology; D013927:Thrombosis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D016277:Ventricular Function, Left / Q000502:physiology*