title: Role of echocardiography in the evaluation of syncope: a prospective study.
abstract: OBJECTIVE
  To study the role of echocardiography in the stepwise evaluation of syncope.
  
  
  METHODS
  A prospective observational study with an 18 month follow up.
  
  
  METHODS
  University teaching hospital providing primary and tertiary care.
  
  
  METHODS
  650 consecutive patients with syncope and clinical suspicion of an obstructive valvar lesion, or with syncope not explained by history, physical examination, or a 12 lead ECG, who underwent bidimensional Doppler transthoracic echocardiography.
  
  
  METHODS
  The causes of syncope were assigned using published diagnostic criteria. Echocardiography was considered diagnostic when confirming a suspected diagnosis, or when revealing occult cardiac disease explaining the syncope.
  
  
  RESULTS
  A systolic murmur was identified in 61 of the 650 patients (9%). Severe aortic stenosis was suspected in 20 of these and was confirmed by echocardiography in eight. Follow up excluded further cases of aortic stenosis. In patients with unexplained syncope (n = 155), routine echocardiography showed no abnormalities that established the cause of the syncope. Echocardiography was normal or non-relevant in all patients with a negative cardiac history and a normal ECG (n = 67). In patients with a positive cardiac history or an abnormal ECG (n = 88), echocardiography showed systolic dysfunction (left ventricular ejection fraction < or = 40%) in 24 (27%) and minor non-relevant findings in the remaining 64. Arrhythmias were diagnosed in 12 of the 24 patients with systolic dysfunction (50%), and in 12 of the 64 remaining patients (19%) (p < 0.01).
  
  
  CONCLUSIONS
  Echocardiography was most useful for assessing the severity of the underlying cardiac disease and for risk stratification in patients with unexplained syncope but with a positive cardiac history or an abnormal ECG.
authors.affiliation: Department of Internal Medicine, Hôpital Cantonal, University of Geneva Medical School, Geneva, Switzerland. francois.sarasin@hcuge.ch
authors.forename: F P
authors.initials: FP
authors.lastname: Sarasin
authors.forename: A-F
authors.initials: AF
authors.lastname: Junod
authors.forename: D
authors.initials: D
authors.lastname: Carballo
authors.forename: S
authors.initials: S
authors.lastname: Slama
authors.forename: P-F
authors.initials: PF
authors.lastname: Unger
authors.forename: M
authors.initials: M
authors.lastname: Louis-Simonet
mesh_terms: D000368:Aged; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D013575:Syncope / Q000000981:diagnostic imaging* / Q000209:etiology