A new simplified method for calculating mean mitral pressure gradient.

BACKGROUND

Mean mitral valve pressure gradient (MVPG) is one of the key measures of the severity of mitral stenosis. The method for calculating MVPG, however, is complex and time consuming. The purpose of this study is to establish a new simple method for calculating MVPG.

METHODS

Hemodynamic data were analyzed in 105 patients who underwent percutaneous balloon mitral valvuloplasty (PBMV). A new simplified method for calculating mitral pressure gradient was proposed, i.e., mean MVPG = MLAP - LVEDP/2, where MLAP is mean left atrial pressure, and LVEDP is left ventricular end-diastolic pressure.

RESULTS

MVPGs derived from the standard and the new method were 13.28 +/- 7.42 mm Hg and 13.50 +/- 7.93 mm Hg, respectively, and there was no significant difference between the values of these two methods (P = 0.065). The MVPG derived from the new simplified method correlated closely with that calculated by the standard approach (r = 0.975, P < 0.001). Moreover, there was no significant difference between mitral valve areas (MVA) derived from the standard and the new approach either before or after PBMV in the 38 patients in whom cardiac output was measured.

CONCLUSION

We conclude that mitral pressure gradient can be calculated reliably with our new simplified method.