title: Efficacy of anticoagulation in resolving left atrial and left atrial appendage thrombi: A transesophageal echocardiographic study.
abstract: BACKGROUND
  Transesophageal echocardiography (TEE) is the gold standard for evaluation of the left atrium and the left atrial appendage (LAA) for the presence of thrombi. Anticoagulation is conventionally used for patients with atrial fibrillation to prevent embolization of atrial thrombi. The mechanism of benefit and effectiveness of thrombi resolution with anticoagulation is not well defined.
  
  
  RESULTS
  We used a TEE database of 9058 consecutive studies performed between January 1996 and November 1998 to identify all patients with thrombi reported in the left atrium and/or LAA. One hundred seventy-four patients with thrombi in the left atrial cavity (LAC) and LAA were identified (1.9% of transesophageal studies performed). The incidence of LAA thrombi was 6.6 times higher than LAC thrombi (151 vs 23, respectively). Almost all LAC thrombi were visualized on transthoracic echocardiography (90.5%). Mitral valve pathology was associated with LAC location of thrombi (P <.0001), whereas atrial fibrillation or flutter was present in most patients with LAA location of thrombi. Anticoagulation of 47 +/- 18 days was associated with thrombus resolution in 80.1% of the patients on follow-up TEE. Further anticoagulation resulted in limited additional benefit.
  
  
  CONCLUSIONS
  LAC thrombi are rare and are usually associated with mitral valve pathology. Transthoracic echocardiography is effective in identifying these thrombi. LAA thrombi occur predominantly in patients with atrial fibrillation or flutter. Short-term anticoagulation achieves a high rate of resolution of LAA and LAC thrombi but does not obviate the need for follow-up TEE.
authors.affiliation: Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
authors.forename: W A
authors.initials: WA
authors.lastname: Jaber
authors.forename: D L
authors.initials: DL
authors.lastname: Prior
authors.forename: M
authors.initials: M
authors.lastname: Thamilarasan
authors.forename: R A
authors.initials: RA
authors.lastname: Grimm
authors.forename: J D
authors.initials: JD
authors.lastname: Thomas
authors.forename: A L
authors.initials: AL
authors.lastname: Klein
authors.forename: C R
authors.initials: CR
authors.lastname: Asher
mesh_terms: D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy*; D016279:Atrial Function, Left; D016001:Confidence Intervals; D004452:Echocardiography; D017548:Echocardiography, Transesophageal; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006331:Heart Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011336:Probability; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013923:Thromboembolism / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*
chemical_list: D000925:Anticoagulants