Background: Left and right ventricular diastolic filling pressures are of clinical importance in both patient treatment and prognosis of cardiac and pulmonary diseases. Purpose: To assess the ability of TDI - as a noninvasive method- to predict left ventricular filling pressures testing the validity of the current indices taking into consideration the controversies surrounding them and trying to drive new indices. In addition we assess its ability to predict right ventricular filling pressure especially in the presence of few data regarding this issue. Patients and methods: The study population comprised two parallel groups of consecutive patients. The study groups were: Group A. In which conventional Doppler and TDI-derived echocardiographic variables were correlated with invasively measured LVEDP. Group B. In which conventional Doppler and TDI-derived echocardiographic variables were correlated with invasively measured RAP via a central venous catheterization. Results: In group A. The median age of the patients was 55.5 years, 68% of them were males. Among all conventional and TDI indices measured, all conventional indices (E velocity, A velocity, E DT and E/A) together with both A’ velocity and E’/A’ showed the strongest correlation with LVEDP (r=0.59, P < 0.001) especially in patients with advanced diastolic dysfunction (r= 0.77, p < 0.01). Multiple regression analysis revealed that E’/A’ is the best predictor of LVEDP having the greatest standardized coefficient B (0.4). Using linear regression analysis E’/A’ showed the best model to predict the LVEDP (R=0.63, p < 0.001) especially in patients with advanced diastolic dysfunction (R=0.74, p< 0.001). Using ROC analysis, E-DT ≤ 158 m/sec can predict elevated LVEDP (> 15 mm Hg) with 86.4% sensitivity and 84% specificity. In patient with advanced diastolic dysfunction A’ velocity ≤ 10.5 cm/sec and E’/A’ ≥ 1.29 can predict elevated LVEDP with specificity of 100% and sensitivity of 93.8% and 70% respectively. In group B, the median age of the patients was 50 years, 76% of them were males. Regression analysis showed that E’ velocity, IVRT, S duration and A velocity were the most important predictors of RAP. ROC analysis revealed that E/E’ > 3 is associated with 89% sensitivity and 100% specificity to detect RAP > 10 mmHg and IVRT ≤ 66.5 m/sec was associated with 79% sensitivity and 100 % specificity to detect RAP > 10 mm Hg. Conclusions: Among conventional and tissue Doppler variables including the E/E’ ratio, E’/A’ ratio is the best index to estimate LVEDP especially in patients with advanced diastolic dysfunction (grade II and III). Both tricuspid E/E’ ratio and IVRT are useful Doppler indices for non-invasive estimation of RAP.