In the absence of mitral valve disease left atrial (LA) volume is a marker of diastolic dysfunction and its severity. This study investigated the relationship between left ventricular (LV) end diastolic pressure (LVEDP) and LA volumes and phasic atrial functions detected by real-time full volume three-dimensional echocardiography (RT3DE), in a patient population with preserved LV systolic function. Seventy-two (39 female and 33 male; mean age 56.1 ± 9.0 years) stable patients with normal LV ejection fraction (EF) undergoing cardiac catheterization were studied. All patients underwent comprehensive echocardiographic examination just before catheterization and LVEDP was obtained. In addition to conventional echocardiographic measurements and Doppler indices; by using RT3DE LA maximum, minimum and pre-a-wave volumes were measured; LA total, passive and active emptying volumes and fractions were calculated. LV systolic function was assessed by EF and global longitudinal strain by speckle tracking. RT3DE minimum LA volume index, RT3DE active LAEF and LA expansion index (EI) were statistically significant univariate predictors of LVEDP ≥ 16 mmHg. When age and hypertension adjusted multivariate analysis was performed EI [β = -1.741, p = 0.015; OR 0.175; 95 % CI (0.043-0.717)] was an independent predictor of elevated LVEDP. RT3DE evaluation of LA function during entire cardiac cycle has incremental value for the diagnosis of diastolic dysfunction in patients with preserved EF. We suggest that RT3DE evaluation of LA may find clinical application in this field.