Reliability of the Doppler pressure half-time method for assessing effects of percutaneous mitral balloon valvuloplasty.

The mitral valve areas determined by Doppler pressure half-time and by cardiac catheterization with use of the Gorlin formula were compared in 18 adult patients who underwent percutaneous mitral balloon valvuloplasty. Doppler measurements and catheterization were performed simultaneously before, immediately after and 24 to 48 h after valvuloplasty. A high correlation between Doppler- and catheterization-derived mitral valve areas was found before mitral valvuloplasty (r = 0.81, Y = 0.88X + 0.1, SEE = 0.11 cm2) and 24 to 48 h after valvuloplasty (r = 0.84, Y = 0.70X + 0.67, SEE = 0.20 cm2). In contrast, the correlation immediately after valvuloplasty was only moderate (r = 0.72, Y = 0.43X + 1.1, SEE = 0.49 cm2). The Doppler-derived mitral valve area (2.41 +/- 0.61 cm2) immediately after valvuloplasty was significantly larger than the catheterization-derived area (2.08 +/- 0.39 cm2, p less than 0.05). In conclusion, the Doppler echocardiographic measurement performed with the pressure half-time method may lead to significant error immediately after mitral balloon valvuloplasty, but clinically accurate measurement can be obtained 24 to 48 h after valvuloplasty.