title: Possible refinement of clinical thromboembolism assessment in patients with atrial fibrillation using echocardiographic parameters.
abstract: OBJECTIVE
  Some transoesophageal echocardiogram (TEE) findings are associated with an increased risk of stroke in patients with atrial fibrillation (AF). This study was designed to evaluate and compare the accuracy of CHADS(2) and CHA(2)DS(2)-VASc in the prediction of these findings and test the additive value of transthoracic echocardiogram (TTE)-derived parameters as a possible refinement for these classifications.
  
  
  RESULTS
  Cross-sectional study of 405 consecutive patients who underwent TTE and TEE evaluation during AF. Stroke risk assessment was performed using the CHADS(2) and CHA(2)DS(2)-VASc scores, alone and alongside with the addition of two TTE-derived parameters (left atrium area and left ventricle global systolic function). Comparisons regarding the presence of left atrial appendage thrombi (LAA T), dense spontaneous echo contrast (SEC), and left atrial appendage (LAA) low flow velocities (LFV) were performed using receiver operating characteristic curves. In low-risk patients, as assessed through the CHA(2)DS(2)-VASc score and CHADS(2) and CHA(2)DS(2)-VASc scores plus echo parameters, no high-risk features were found on TEE. In subjects classified as low risk using CHADS(2), this figure rose to 10%. No significant differences were found between CHADS(2) and CHA(2)DS(2)-VASc in the prediction of LAA T, dense SEC, and LAA LFV. The addition of TTE-derived parameters to the previous clinical-risk scores resulted in improved prediction of the TEE endpoints.
  
  
  CONCLUSIONS
  These findings suggest that the use of TTE-derived parameters may be a valuable way of refining the available clinical risk schemes for the detection of surrogate markers of stroke. Follow-up studies using clinical endpoints will be necessary to confirm this hypothesis.
authors.affiliation: Cardiology Department, Coimbra's Hospital Center and University, Coimbra, Portugal. rui_providencia@yahoo.com
authors.forename: Rui
authors.initials: R
authors.lastname: Providência
authors.forename: Ana
authors.initials: A
authors.lastname: Botelho
authors.forename: Joana
authors.initials: J
authors.lastname: Trigo
authors.forename: Nuno
authors.initials: N
authors.lastname: Quintal
authors.forename: José
authors.initials: J
authors.lastname: Nascimento
authors.forename: Paula
authors.initials: P
authors.lastname: Mota
authors.forename: António
authors.initials: A
authors.lastname: Leitão-Marques
mesh_terms: D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging / Q000503:physiopathology; D001281:Atrial Fibrillation / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D004452:Echocardiography / Q000379:methods*; D017548:Echocardiography, Transesophageal / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012372:ROC Curve; D018570:Risk Assessment; D020521:Stroke / Q000209:etiology; D013923:Thromboembolism / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology