title: Color Doppler sonographic signs of respiration-dependent hepatofugal portal flow.
abstract: OBJECTIVE
  The role of respiration in modulating blood flow in the portal vein is unclear. The aim of this study was to investigate the phenomenon of respiration-dependent periodic hepatofugal portal venous blood flow as detected on color Doppler sonography.
  
  
  METHODS
  Within 1 year, we identified 13 patients with respiration-dependent reversal of blood flow in the portal vein that was diagnosed on color Doppler sonography. This phenomenon was investigated by color Doppler sonographic examination of the portal venous flow during both mid-inspiration breath-holding and a respiratory cycle including deep inspiration; evaluation of hepatic vein Doppler waveforms as normal (triphasic) or decreased (flattened); and echocardiographic examination to determine the presence or absence of tricuspid regurgitation.
  
  
  RESULTS
  The patients' median age was 53 years (range, 26-87 years). Seven of the 13 patients had heart disease (tricuspid regurgitation) with or without liver disease, 3 had liver disease without heart disease, and 3 had other diseases with no evidence of heart or liver disease. On Doppler sonography, 10 of the 13 patients had increased portal venous pulsatility (7 of the 10 had tricuspid regurgitation; the other 3 did not); the remaining 3 patients had neither increased pulsatility nor tricuspid regurgitation. Sonographic follow-up within 4 weeks in 4 of the 13 patients revealed loss of the respiration-dependent hepatofugal portal flow.
  
  
  CONCLUSIONS
  Respiration-dependent hepatofugal portal flow is a rare finding associated with periodic portal hypertension in patients with right heart insufficiency and liver disease. Its clinical significance is unclear. Among our patients, its occurrence was predominantly associated with an increased venous pulsatility index due to tricuspid regurgitation or venous outflow obstruction. Further study is needed to investigate whether periodic respiration-dependent hepatofugal portal flow is predictive of the occurrence of continuous flow reversal.
authors.affiliation: Department of Internal Medicine, Philipps University, Baldingerstrasse, 35043 Marburg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Görg
authors.forename: Ulf
authors.initials: U
authors.lastname: Seifart
authors.forename: Gerhard
authors.initials: G
authors.lastname: Zugmaier
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008107:Liver Diseases / Q000150:complications; D008297:Male; D008875:Middle Aged; D010507:Periodicity; D011169:Portal Vein / Q000000981:diagnostic imaging*; D012039:Regional Blood Flow; D012119:Respiration; D018615:Ultrasonography, Doppler, Color