[Detection of an intrapulmonary shunt in patients with liver cirrhosis through contrast-enhanced transcranial Doppler. A study of prevalence, pattern characterization, and diagnostic validity]

Gastroenterol Hepatol. 2015 Oct;38(8):475-83. doi: 10.1016/j.gastrohep.2015.02.006. Epub 2015 Apr 1.
[Article in Spanish]

Abstract

Introduction: Intrapulmonary vascular dilatations (IPVD) are considered a complication of cirrhosis. The technique of choice for their diagnosis is contrast-enhanced echocardiography (CEE). The aim of this study was to determine the usefulness of contrast-enhanced transcranial Doppler (CETD) in the diagnosis of IPVD.

Method: We consecutively included patients evaluated for liver transplantation. A cross-sectional study was conducted. The investigator interpreting CETD was blind to the results of the gold standard (CEE). The accuracy of the diagnostic test was evaluated through sensitivity, specificity, positive and negative predictive values, and likelihood ratio.

Results: CETD (n=43) showed a right-to-left shunt in 23 patients (62.2%): 4 early, 2 indeterminate and 17 late. Nineteen (51,4%) cases were classified as IPVD. With CEE (n=37), 10 procedures (27%) were negative for shunt, 27 (73%) were positive, and 21 (56.8%) were compatible with IPVD. Patients with and without IPVD showed no differences in age, sex, etiology, severity, or MELD score, independently of the diagnostic test. In the diagnostic validity study (n=37) of CETD versus CEE, the AUC for diagnostic yield was 0.813% (95%CI: 0.666-0.959; P=.001), sensitivity was 76.2% (95%CI: 54.9-89.4) and specificity was 90% (95%CI: 63.9-96.5). The positive likelihood ratio was 6.095.

Conclusions: We found a high prevalence of IPVD in candidates for liver transplantation. When a late right-to-left shunt with recirculation is observed, CETD has a high probability of detecting IPVD, with few false-positive results. Because this technique has not previously been described in this indication, similar studies are needed for comparison.

Keywords: Cirrhosis; Cirrosis; Contrast-enhanced echocardiography; Contrast-enhanced transcranial Doppler; Diagnostic validity studies; Dilataciones vasculares pulmonares; Doppler transcraneal con contraste; Ecocardiografía con contraste; Estudios de validez diagnóstica; Hepatopulmonary syndrome; Liver transplantation; Pulmonary vascular dilatations; Síndrome hepatopulmonar; Trasplante hepático.

Publication types

  • Comparative Study
  • Validation Study

MeSH terms

  • Aged
  • Area Under Curve
  • Capillaries / diagnostic imaging*
  • Capillaries / pathology
  • Contrast Media
  • Cross-Sectional Studies
  • Dilatation, Pathologic
  • Echocardiography
  • Female
  • Hepatopulmonary Syndrome / diagnostic imaging*
  • Hepatopulmonary Syndrome / epidemiology
  • Hepatopulmonary Syndrome / etiology
  • Humans
  • Liver Cirrhosis / complications*
  • Male
  • Microbubbles
  • Middle Aged
  • Predictive Value of Tests
  • Prevalence
  • Prospective Studies
  • Pulmonary Circulation*
  • Sensitivity and Specificity
  • Single-Blind Method
  • Ultrasonography, Doppler, Transcranial*
  • Valsalva Maneuver

Substances

  • Contrast Media