title: Warfarin therapy initiated before is more beneficial than after transesophageal echocardiography detected left atrial thrombus.
abstract: OBJECTIVE
  Warfarin anticoagulation significantly reduces the risk of thromboembolism in patients with atrial fibrillation (AF). However, there are many patients with AF who begin anticoagulation only after left atrial thrombus (LAT) is detected by transesophageal echocardiography (TEE). The impact of anticoagulation in these patients has not been clearly described. The purpose of this study was to investigate the incidence of cerebrovascular accident (CVA) among AF patients who began warfarin before LAT was detected by TEE compared to those who began warfarin only after TEE demonstrated LAT and those did not receive warfarin at any point.
  
  
  METHODS
  Of the 90 consecutive AF patients with LAT (male 48, female 42, age 71.5 +/- 10.1 years), 49 began warfarin more than 3 weeks before TEE (Group I); 29 began warfarin after TEE (Group II); and 12 did not receive warfarin at all (Group III).
  
  
  RESULTS
  The incidence of CVA in Group I (14%, 7/49, prior CVA 5, new CVA after TEE 2) was significantly lower than Group II (45%, 13/29, prior CVA 10, new CVA after TEE 3, P = 0.006) and III (42%, 5/12, prior CVA 3, new CVA after TEE 2, P = 0.047). Patients with persistent LAT had significantly higher incidence (64% vs 23%, P = 0.024) of CVA and lower CVA free survival than those with resolved LAT.
  
  
  CONCLUSIONS
  The incidence of CVA among AF patients, who began warfarin before LAT detection, is significantly lower than those who began warfarin after LAT detection as well as those who did not receive warfarin at all.
authors.affiliation: The Cardiac Center of Creighton University, Omaha, Nebraska 68131-2044, USA. xshen@cardiac.creighton.edu
authors.forename: Xuedong
authors.initials: X
authors.lastname: Shen
authors.forename: Huagui
authors.initials: H
authors.lastname: Li
authors.forename: Chandra K
authors.initials: CK
authors.lastname: Nair
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Holmberg
authors.forename: Dhanunjay
authors.initials: D
authors.lastname: Lakkireddy
authors.forename: David
authors.initials: D
authors.lastname: Cloutier
authors.forename: Karen
authors.initials: K
authors.lastname: Rovang
authors.forename: Tom
authors.initials: T
authors.lastname: Hee
authors.forename: Aryan N
authors.initials: AN
authors.lastname: Mooss
authors.forename: Syed M
authors.initials: SM
authors.lastname: Mohiuddin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage* / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000150:complications* / Q000000981:diagnostic imaging; D017548:Echocardiography, Transesophageal; D005260:Female; D006325:Heart Atria; D006331:Heart Diseases / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012306:Risk; D020521:Stroke / Q000453:epidemiology / Q000209:etiology*; D013923:Thromboembolism / Q000209:etiology / Q000517:prevention & control*; D013927:Thrombosis / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D013997:Time Factors; D014859:Warfarin / Q000008:administration & dosage* / Q000627:therapeutic use
chemical_list: D000925:Anticoagulants; D014859:Warfarin