An elevated left ventricular (LV) filling pressure is the main finding in patients with heart failure with preserved ejection fraction (HFpEF), and LV filling pressure is estimated with an algorithm in the recent American Society of Echocardiography (ASE)/European Association of Cardiovascular Imaging (EACVI) guideline. In this study, we sought to determine the efficacy of LA global longitudinal strain to estimate elevated LV filling pressure. Seventy-one consecutive patients (mean age of 63.2 +/- 9.75, 70% male) who underwent left ventricular catheterization were included. Transthoracic echocardiography was performed within 24 h before catheterization. The LV filling pressure was estimated using echo parameters based on the 2016 ASE/EACVI algorithm. LA GLS was measured using 2D speckle tracking echocardiography in a four-chamber view (GE, Vivid E9 USA). Invasive LV pre-A pressure corresponding to the mean left atrial pressure (LAP) was used as a reference, and > 12 mm Hg was defined as elevated. Invasive LV filling pressure was defined as elevated in 41 (58%) and normal in 30 patients (42%). The LV filling pressure of 9 (13%) of 71 patients was defined as indeterminate based on the 2016 algorithm. Using the ROC method, 25.5% of LA reservoir strain (LASr) had a higher sensitivity (AUC = 0.79, specificity 77%, sensitivity 80%) in estimating LV filling pressure than the 2016 ASE/EACVI algorithm (AUC = 0.75, specificity 77%, sensitivity 70%). LASr, with higher sensitivity than 2016 ASE/EACVI algorithm, may be used as a single parameter to estimate LV filling pressure and hence may add incremental value toHFpEF diagnosis.