title: Low incidence of left atrial or left atrial appendage thrombus in patients with paroxysmal atrial fibrillation and normal EF who present for pulmonary vein antrum isolation procedure.
abstract: BACKGROUND
  The incidence of left atrial appendage (LAA) thrombus in patients with paroxysmal atrial fibrillation (PAF) who present for pulmonary vein antrum isolation procedure (PVAI) is unknown.
  
  
  RESULTS
  All consecutive patients from January 2000 to June 2004 who underwent a PVAI received a computed tomography (CT) to evaluate LAA thrombus before the procedure and 3 months post-PVAI. All patients were followed prospectively. One thousand two hundred twenty-one patients received a PVAI during the study dates. All patients received a CT pre-PVAI at 3 months, and 601 (49%) received a transesophageal echocardiography (TEE) pre-PVAI. Per protocol, all patients who had CT scans that were positive for LAA thrombus received a TEE. There were 9 patients who had LAA thrombus on CT scan, but only 3 had LAA thrombus on TEE. Using TEE as the gold standard, only 3 patients had an LAA thrombus before PVAI; of these patients, 2 had chronic AF with average ejection fraction (EF) of 48% and 1 patient had PAF with EF 25%. No patients with PAF and normal EF had LAA thrombus. Patients with LAA thrombus pre-PVAI had lower EF than patients without LAA thrombus (40% vs. 53%, P = 0.007) but had similar LA size (5.0 vs. 4.5 cm, P = 0.77). No other differences in baseline characteristics were noted.
  
  
  CONCLUSIONS
  In this registry of 1,221 patients, we did not observe LA thrombus in PAF patients with normal EF who present for PVAI. Prescreening CT alone is likely to be sufficient in paroxysmal AF patients with normal EF, and the use of TEE may not be needed.
authors.affiliation: Department of Cardiology, Cleveland Clinic Foundation, Cleveland, Ohio, USA.
authors.forename: Mohammed N
authors.initials: MN
authors.lastname: Khan
authors.forename: Ali
authors.initials: A
authors.lastname: Usmani
authors.forename: Saira
authors.initials: S
authors.lastname: Noor
authors.forename: Samy
authors.initials: S
authors.lastname: Elayi
authors.forename: Chi Keong
authors.initials: CK
authors.lastname: Ching
authors.forename: Luigi
authors.initials: L
authors.lastname: Di Biase
authors.forename: Dimpi
authors.initials: D
authors.lastname: Patel
authors.forename: J David
authors.initials: JD
authors.lastname: Burkhardt
authors.forename: Jennifer
authors.initials: J
authors.lastname: Cummings
authors.forename: Robert
authors.initials: R
authors.lastname: Schweikert
authors.forename: Walid
authors.initials: W
authors.lastname: Saliba
authors.forename: Andrea
authors.initials: A
authors.lastname: Natale
mesh_terms: D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000706:statistics & numerical data*; D005260:Female; D006325:Heart Atria; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009820:Ohio / Q000453:epidemiology; D011667:Pulmonary Veins / Q000601:surgery*; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D013318:Stroke Volume; D013927:Thrombosis / Q000453:epidemiology*; D016896:Treatment Outcome