Letter regarding article by Diwan et al, "Doppler estimation of left ventricular filling pressures in patients with mitral valve disease".

BACKGROUND Conventional Doppler measurements have limitations in the prediction of left atrial pressure (LAP) in patients with mitral valve disease (MVD), given the confounding effect of valve area, left ventricular (LV) relaxation, and stiffness. However, the time interval between the onset of early diastolic mitral inflow velocity (E) and annular early diastolic velocity (Ea) by tissue Doppler imaging (TDI), T(E-Ea), which is well related to the time constant of LV relaxation (tau) in canine and clinical studies, is not subject to these variables. We therefore undertook this study to test its usefulness in a patient population. METHODS AND RESULTS Two-dimensional Doppler and TDI echocardiography were performed simultaneously with right-heart catheterization in 51 consecutive patients (mean+/-SD age, 64+/-11 years) with MVD: 35 with moderately severe to severe mitral regurgitation (MR) and 16 with moderate to severe mitral stenosis (MS). Among several Doppler measurements, only the mitral E/A ratio, isovolumetric relaxation time (IVRT), and pulmonary venous Ar duration had significant relations with mean pulmonary capillary wedge pressure (PCWP). The ratio of IVRT to T(E-Ea) (for MR, r=-0.92; for MS, r=-0.88; both P<0.001) and the ratio of IVRT to tau (for MR, r=-0.74; for MS, r=-0.85; both P<0.001) had the best correlations with PCWP. In 54 repeat studies, including those performed after MV repair or replacement, these ratios tracked well the changes in PCWP and readily identified changes in mean PCWP by > or =5 mm Hg. A similar correlation was noted in 13 patients with atrial fibrillation (r=-0.92, P<0.01) and in a prospective group of 14 patients with MR (r=-0.93, P<0.001). CONCLUSIONS The ratio of IVRT to T(E-Ea) or to tau can be readily applied for estimating mean PCWP in patients with MVD and can track changes in PCWP after valve surgery.