title: [Low sensitivity of the echocardiograph compared with contrast transcranial Doppler in right-to-left shunt].
abstract: BACKGROUND
  Contrast transcranial Doppler (c-TCD) has a high sensitivity for detecting right-to-left shunt (RLS), and is probably higher than transthoracic echocardiography (TTE) and comparable with transesophageal echocardiography (TEE).
  
  
  OBJECTIVE
  To evaluate the accuracy of echocardiography (TTE and TEE) to detect RLS compared to c-TCD.
  
  
  METHODS
  Observational study of patients <55 years old with cerebral ischaemia of undetermined origin (2007-2009). All underwent c-TCD monitoring to detect RLS, at rest and after Valsalva manoeuvre (VM). The TTE and TEE were performed when indicated by our cerebrovascular protocol. The accuracy of TTE and TEE for detecting RLS was calculated by comparing them with c-TCD.
  
  
  RESULTS
  A total of 115 patients with c-TCD, mean age 43.3 (SD 10.3) years, 51.3% male. The TTE was performed in 102, and TEE in 81, patients. RLS detection was higher with c-TCD than with TTE (67.6% vs. 22.5%, P=.001) or TEE (77.8% vs. 53.1%, P=.001). The TTE, compared with c-TCD after MV showed: sensitivity 31.8%, specificity 96.9%, positive predictive value (PPV) 95.6%, negative predictive value (NPV) 40.5% and accuracy 52.9% to detect RLS. TEE, compared with c-TCD after MV showed: sensitivity 63.4%, specificity 83.3%, PPV 93%, NPV 39.4% and accuracy 67.9%. The accuracy of TTE and TEE improved when they were compared with c-TCD at rest.
  
  
  CONCLUSIONS
  TTE and TEE show a considerable number of false negatives for RLS detection. Clinical studies should consider the c-TCD as the best technique to diagnose RLS when a paradoxical embolism is suspected.
authors: Laboratorio de Exploración Neurovascular Ultrasonográfica, Servicio de Neurología y Centro de Ictus, Hospital Universitario La Paz, Universidad Autónoma de Madrid, Instituto de Investigación IdiPAZ, Madrid, España. patrindalo@hotmail.com
authors: P
authors: P
authors: Martínez-Sánchez
authors: J
authors: J
authors: Medina-Báez
authors: M
authors: M
authors: Lara-Lara
authors: J
authors: J
authors: Oliva-Navarro
authors: R
authors: R
authors: Cazorla-García
authors: G
authors: G
authors: Ruiz-Ares
authors: M
authors: M
authors: Martínez-Martínez
authors: B
authors: B
authors: Fuentes
authors: E
authors: E
authors: Díez-Tejedor
mesh_terms: D000328:Adult; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000209:etiology*; D003287:Contrast Media; D004452:Echocardiography; D017548:Echocardiography, Transesophageal; D019320:Embolism, Paradoxical / Q000000981:diagnostic imaging / Q000209:etiology*; D005260:Female; D054092:Foramen Ovale, Patent / Q000000981:diagnostic imaging*; D006801:Humans; D020766:Intracranial Embolism / Q000000981:diagnostic imaging / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D003287:Contrast Media