title: Association of follow-up change of left atrial appendage blood flow velocity with spontaneous echo contrast in nonrheumatic atrial fibrillation.
abstract: OBJECTIVE
  To evaluate the time-related change of left atrial (LA) appendage flow velocity in chronic atrial fibrillation (AF) by follow-up transesophageal echocardiography (TEE) and to investigate its association with the occurrence of LA spontaneous echo contrast.
  
  
  METHODS
  Prospective follow-up study.
  
  
  METHODS
  University-based, tertiary referral medical center.
  
  
  METHODS
  Forty-seven patients with chronic nonrheumatic AF.
  
  
  METHODS
  All studied patients underwent both a baseline and follow-up TEE during a mean period of 13 +/- 7 months.
  
  
  RESULTS
  Baseline TEE revealed that LA spontaneous echo contrast was present in 28 patients (group 1) and was absent in 19 patients (group 2). The LA appendage flow velocity profiles at baseline were significantly lower in group 1 than in group 2; on follow-up, the appendage flow velocities decreased significantly in group 2, but were not significantly changed in group 1. Follow-up TEE revealed that spontaneous echo contrast was persistent in all group 1 patients. In group 2, LA spontaneous echo contrast was newly observed in 9 patients (group 2A) but was persistently absent in 10 patients (group 2B). In group 2A, all of the LA appendage flow velocity profiles decreased significantly at the follow-up study. In group 2B, however, only LA appendage inflow velocity integral showed significant decrease on follow-up; there were no significant changes in LA appendage outflow velocity indexes and peak inflow velocity.
  
  
  CONCLUSIONS
  LA appendage flow velocity may decrease with time in some patients with AF, and this change is associated with a new occurrence of LA spontaneous echo contrast. For patients without LA spontaneous echo contrast, serial follow-up of the LA appendage flow velocity profiles may be useful for predicting future development of spontaneous echo contrast. Once LA spontaneous echo contrast occurs in AF patients, it tends to persist with time and the LA appendage is usually under a persistently low flow state.
authors.affiliation: Department of Internal Medicine, National Cheng Kung University Medical College and Hospital, Tainan, Taiwan, Republic of China.
authors.forename: L M
authors.initials: LM
authors.lastname: Tsai
authors.forename: T H
authors.initials: TH
authors.lastname: Chao
authors.forename: J H
authors.initials: JH
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging*; D001281:Atrial Fibrillation / Q000150:complications / Q000000981:diagnostic imaging*; D016279:Atrial Function, Left / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology; D009202:Cardiomyopathies / Q000150:complications / Q000000981:diagnostic imaging; D002908:Chronic Disease; D017548:Echocardiography, Transesophageal; D005260:Female; D005500:Follow-Up Studies; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D020766:Intracranial Embolism / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D011446:Prospective Studies; D012307:Risk Factors; D013927:Thrombosis / Q000000981:diagnostic imaging*