Doppler tissue imaging: a reliable method for estimation of left ventricular filling pressure in patients with mitral regurgitation.
Doppler of mitral and pulmonary vein flows are used to estimate left ventricular (LV) filling pressure. Mitral regurgitation (MR) makes unreliable these parameters by inducing changes of both mitral inflow and pulmonary vein flow. To evaluate whether Doppler tissue imaging (DTI) diastolic indices obtained at the level of LV lateral mitral annulus can provide accurate estimation of LV filling pressure in patients with MR. Forty-three patients (age 55 +/- 11 years) with severe MR and mean LV ejection fraction (EF) 58 +/- 13 were enrolled, 10 (23%) with LV EF < 50% and 33 (77%) with LV EF > 50%. Doppler signals from the mitral inflow, pulmonary venous flow, and DTI indices of the lateral mitral annulus were obtained. LV end-diastolic pressure (LVEDP) was measured invasively with fluid-filled catheter. In the overall population, the majority of standard Doppler and DTI indices correlated with LVEDP, but the multivariate analysis showed that the ratio of mitral velocity to early diastolic velocity of the mitral annulus (E/Em ratio) (beta = .87, P = .0001) was independent predictor of LVEDP (R2 = 0.74, SE = 4, P = .0001). An E/Em ratio > 10 predicted an LVEDP > 15 mm Hg (sensitivity 90%, specificity 83%). In both groups with LV EF > 50% (beta = .77, P = .005; cumulative R2 = 0.73, SE = 2.5, P = .0001) and < 50% (beta = .89, P = .002; cumulative R2 = 0.77, SE = 2.1, P = .002), multivariate analysis underscored again only E/Em ratio as independent predictor of LVEDP. The combination of DTI indices of the mitral annulus and mitral inflow velocities provides reliable parameters to predict LV filling pressure in patients with MR both in patients with LV EF > 50% and < 50%.