Normal ECG, CVP & HV Waveforms

In hepatic vein Doppler, the retrograde A-wave reflects right atrial contraction in late diastole, just after the P wave and before ventricular systole. This brief rise in right atrial pressure can push flow backwards from the right atrium into the hepatic veins

The antegrade S-wave occurs during ventricular systole. It is mainly produced by downward displacement of the tricuspid annulus/atrioventricular plane, which lowers right atrial pressure and draws blood from the hepatic veins towards the right atrium. The deepest point of the S-wave represents the peak systolic antegrade hepatic venous velocity

The V-wave occurs in late systole, as the right atrium fills while the tricuspid valve remains closed. Its peak corresponds to maximal right atrial filling and occurs just before, or around, tricuspid valve opening, marking the transition into early diastole. Depending on right atrial pressure and venous congestion, the V-wave may remain below the baseline or may cross above it as brief retrograde flow

The antegrade D-wave occurs in early diastole, after the tricuspid valve opens. It reflects rapid emptying of the right atrium into the right ventricle, which again draws blood forward from the hepatic veins. The deepest point of the D-wave represents the peak early diastolic antegrade hepatic venous velocity

In VExUS, the key abnormality is progressive loss of normal systolic forward flow: normally S ≥ D, mild congestion shows S < D while still antegrade, and severe congestion shows systolic flow reversal above the baseline.