Doppler pressure half-time and catheter pressure gradient half-time in the calculation of mitral valve area

ABSTRACT

The use of Doppler derived measurements in the assessment of mitral stenosis [MS.] was evaluated in 45 patients [pts] with rheumatic heart disease and the data were compared with that obtained by cardiac catheterization and direct measurement of the valve orifice area [MVA] at surgery. Results showed that Doppler derived measurements of MVA by pressure half-time method were of particular value in 24 pts in whom technically adequate cross-sectional images and MVA measurements were difficult to obtain.Eighteen of these cases [40%] had heavily calcified and disorganized valves and six pts [13%] had a poor acoustic window. The Doppler data were more accurate than standard two-dimensional measurements in 30 pts.[66%] with atrial fibrillation. The comparison with Gorlin's formula for catheter-derived MVA was poor, especially in the presence of mitral regurgitation or irregular rhythm. Excellent comparisons were obtained with a catheter-derived pressure half-time and surgical assessment of MVA. Thus, The Doppler examination proved to be an invaluable adjunct to a complete assessment of MVA and replaces the need for haemodynamic assessment in most pts with MS