Abstract: The diameters of“a”wave of expiration of 140 normal subjects were recorded by M-mode echocardiography at the distal portion of IVCD.The normal range is 19.56±3.13mm in the group of age 20-59; 11.29±2.12mm/m² in the group of age 7-19.The normal range of the hepatic vein diameter(HVD)was measured at expiration and systole is 6.69±1.64mm in the group of age 20-59;4.35±1.07mm/m² in the group of age 7-19.In patients with heart failure,tricuspid regurtation (TR)and septal defect(SD).The mean value of HVD is significantly different from the normal.The backflow of tracing are presented in the hepatic vein of 97.7% of normal subjects.The peaks of the backflow were applied for the TRand ASD diagnosis.

Key words: echocardiography, inferior vena cava, hepatic vein, contrast method