DETERMINATION OF MITRAL-VALVE AREA IN PATIENTS WITH MITRAL-STENOSIS BY THE FLOW-CONVERGENCE-REGION METHOD DURING CHANGING HEMODYNAMIC CONDITIONS

Twenty-eight patients with mitral stenosis underwent Doppler echocardi ography at rest and during exercise to determine the accuracy of mitra l valve area determination by the flow-convergence-region method durin g exercise-induced changing hemodynamic conditions. The mitral valve a rea calculated by using the flow-convergence-region method correlated strongly with that measured by the Gorlin formula both at rest (r = 0. 85) and during exercise (r = 0.92) for all 28 patients studied. Althou gh mitral valve area obtained by the Row-convergence-region method did not change (p = 0.1) in 16 patients with echocardiographic mitral sco res greater than or equal to 12, it increased significantly during exe rcise (p = 0.0001) in 12 patients with echocardiographic mitral scores <12. This study suggests that in mitral stenosis, the mitral valve ar ea can be accurately estimated by the flow-convergence-region method b oth at rest and during changing hemodynamic conditions induced by supi ne bicycle exercise.