Effects of sample volume location, imaging view, heart rate and age on tricuspid velocimetry in normal subjects.

The effects of imaging view and sample volume location on tricuspid velocimetry and of heart rate and aging on mitral and tricuspid inflow were evaluated in 41 normal subjects aged 20 to 76 years. Pulsed Doppler recordings were obtained in the parasternal short-axis, right ventricular inflow and apical 4-chamber views at the level of the tricuspid and mitral anuli and 1 cm caudad and 1 cm cephalad to the tricuspid anulus in the 4-chamber apical view. The right ventricular filling pattern was not affected by imaging view. However, placement of the sample volume 1 cm cephalad resulted in a 16% reduction (p less than 0.01) in early velocity with a 9% increase in atrial filling fraction. Conversely, late velocity was 11% higher (p less than 0.05) at the anular level versus the other locations. Right and left ventricular filling velocities were modestly related (r = 0.50 to 0.63). Relations between age and tricuspid late velocity, velocity ratio and atrial filling fraction were weaker (r = 0.34 to 0.47; all p less than 0.05) than those between age and mitral variables (r = 0.59 to 0.74. Also, aging had a greater effect on mitral than tricuspid late velocity (i.e., a steeper slope; p less than 0.01). Tricuspid late velocity and atrial filling fraction were each modestly inversely related to RR interval (r = -0.48, r = -0.54; p less than 0.01). Thus, tricuspid velocity is affected by sample volume location, aging and heart rate, but not imaging view. Sample volume location, heart rate and age should be considered when evaluating right ventricular inflow parameters.