Normal hepatic vein Doppler Ultrasound tracing 1) a large antegrade waveform (negative velocity) noted during early and mid-systole (S wave) that corresponds to the " x " descent on RA pressure. It occurs in response to the fall in RA pressure caused by the increase in volume as a result of atrial relaxation and systolic displacement of the tricuspid annulus towards the RV apex 2) a small retrograde wave (positive velocity) in late systole (V-wave), that is occasionally absent, and corresponds to the "v " wave on RA pressure 3) an antegrade wave noted in early and mid-diastole (D-wave) that is less prominent than the S-wave and relates to the " y " descent in the RA. This wave results from the fall in RA pressure that follows tricuspid valve (TV) opening and emptying of the RA into the right ventricle (RV) 4) a retrograde wave noted in late diastole (A-wave) that corresponds to the " a " wave in the RA. This wave is caused by atrial contraction with rise in RA pressure that exceeds IVC pressure, thus leading to flow reversal in the HVs. Dr. Abhilash Koratala - NephroPOCUS @NephroP #Normal #hepaticvein #Doppler #Ultrasound #tracing #diagnosis #pocus
