title: Transthoracic echocardiogram in syncope patients with normal initial evaluation.
abstract: OBJECTIVE
  Despite the low diagnostic yield of echocardiogra0, it is often used in the evaluation of syncope. This study determined whether patients without abnormalities in the initial evaluation benefit from transthoracic echocardiogram (TTE) and the clinical factors predicting an abnormal TTE.
  
  
  METHODS
  This study enrolled 241 patients presenting to the emergency department with syncope. The TTE results were analyzed based on risk factors suggesting cardiogenic syncope in the initial evaluation.
  
  
  RESULTS
  Of the 115 patients with at least one risk factor, 97 underwent TTE and 27 (27.8%) had TTE abnormalities. In comparison, of the 126 patients without risk factors, 47 underwent TTE and only 1 (2.1%) had TTE abnormalities. Significantly different factors between patients with normal and abnormal TTE findings were entered in a multiple logistic regression analysis, which yielded age [adjusted odds ratio (aOR), 1.09; 95% CI, 1.02-1.15; p=0.006], an abnormal electrocardiogram (ECG) (aOR, 7.44; 95% CI, 1.77-31.26; p=0.010), and a brain natriuretic peptide (BNP) level of >100pg/mL (aOR, 2.64; 95% CI, 1.21-5.73; p=0.011) as independent predictors of TTE abnormalities. The cutoff value of age predicting an abnormal TTE was 59.0years (area under the curve, 0.777; p<0.001).
  
  
  CONCLUSIONS
  A patient who is older than 59years or has an abnormal ECG or an elevated BNP level may benefit from TTE. Otherwise, TTE should be deferred in patients with no risk factors in the initial evaluation.
authors.affiliation: Department of Emergency Medicine, Pusan National University Hospital, Busan, Republic of Korea.
authors.forename: Sang-Kyoon
authors.initials: SK
authors.lastname: Han
authors.affiliation: Department of Emergency Medicine, Pusan National University Hospital, Busan, Republic of Korea.
authors.forename: Seok-Ran
authors.initials: SR
authors.lastname: Yeom
authors.affiliation: Department of Emergency Medicine, Pusan National University Hospital, Busan, Republic of Korea.
authors.forename: Sung-Hwa
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Emergency Medicine, Pusan National University Hospital, Busan, Republic of Korea.
authors.forename: Soon-Chang
authors.initials: SC
authors.lastname: Park
authors.affiliation: Department of Emergency Medicine, Pusan National University Hospital, Busan, Republic of Korea.
authors.forename: Hyung-Bin
authors.initials: HB
authors.lastname: Kim
authors.affiliation: Department of Emergency Medicine, Pusan National University Hospital, Busan, Republic of Korea.
authors.forename: Young-Mo
authors.initials: YM
authors.lastname: Cho
authors.affiliation: Department of Emergency Medicine, Pusan National University Hospital, Busan, Republic of Korea. Electronic address: psu52156@naver.com.
authors.forename: Sung-Wook
authors.initials: SW
authors.lastname: Park
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D016009:Chi-Square Distribution; D015897:Comorbidity; D003362:Cost-Benefit Analysis; D004452:Echocardiography / Q000191:economics / Q000379:methods; D004562:Electrocardiography; D004636:Emergency Service, Hospital / Q000191:economics / Q000706:statistics & numerical data*; D005260:Female; D006331:Heart Diseases / Q000150:complications* / Q000175:diagnosis*; D006400:Hematocrit / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D062706:Prodromal Symptoms; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D017678:Sex Distribution; D013575:Syncope / Q000175:diagnosis / Q000209:etiology*; D019210:Troponin I / Q000097:blood
chemical_list: D019210:Troponin I
keywords: Echocardiogram; Electrocardiogram; Syncope