title: Doppler ultrasonography measurement of hepatic hemodynamics during Valsalva maneuver: healthy volunteer study.
abstract: OBJECTIVE
  The aim of our study was to assess the hemodynamic change of liver during the Valsalva maneuver using Doppler ultrasonography.
  
  
  METHODS
  Thirty healthy men volunteers were enrolled (mean age, 25.5±3.64 years). The diameter, minimal and maximal velocities, and volume flow of intrahepatic inferior vena cava (IVC), middle hepatic vein (MHV), and right main portal vein (RMPV) was measured during both rest and Valsalva maneuver. These changes were compared using paired t-test.
  
  
  RESULTS
  The mean diameters (cm) of the intrahepatic IVC at rest and Valsalva maneuver were 1.94±0.40 versus 0.56±0.66 (P<0.001). The mean diameter (cm), minimal velocity (cm/sec), maximal velocity (cm/sec), and volume flow (mL/min) of MHV at rest and Valsalva maneuver were 0.60±0.15 versus 0.38±0.20 (P<0.001), -7.98±5.47 versus 25.74±13.13 (P<0.001), 21.34±6.89 versus 35.12±19.95 (P=0.002), and 106.94±97.65 versus 153.90±151.80 (P=0.014), respectively. Those of RMPV at rest and Valsalva maneuver were 0.78±0.21 versus 0.76±0.20 (P=0.485), 20.21±8.22 versus 18.73±7.43 (P=0.351), 26.79±8.85 versus 24.93±9.91 (P=0.275), and 391.52±265.63 versus 378.43±239.36 (P=0.315), respectively.
  
  
  CONCLUSIONS
  The blood flow velocity and volume flow of MHV increased significantly during Valsalva maneuver. These findings suggest that hepatic vein might play an important role to maintain venous return to the heart during the maneuver.
authors.affiliation: Department of Radiology, Wonkwang University School of Medicine, Iksan, Korea.
authors.forename: Dong-Ho
authors.identifier: 0000-0002-6005-4268
authors.initials: DH
authors.lastname: Bang
authors.affiliation: Department of Radiology, Wonkwang University School of Medicine, Iksan, Korea.
authors.forename: Youngjun
authors.identifier: 0000-0002-5067-3954
authors.initials: Y
authors.lastname: Son
authors.affiliation: Department of Radiology, Wonkwang University School of Medicine, Iksan, Korea.
authors.forename: Young Hwan
authors.identifier: 0000-0001-5893-6571
authors.initials: YH
authors.lastname: Lee
authors.affiliation: Department of Radiology, Wonkwang University School of Medicine, Iksan, Korea.
authors.forename: Kwon-Ha
authors.identifier: 0000-0002-2634-8510
authors.initials: KH
authors.lastname: Yoon
keywords: Hemodynamics; Hepatic veins; Liver; Ultrasonography, Doppler; Valsalva maneuver