Background: Tricuspid annular plane systolic excursion (TAPSE) connected to pulmonary artery systolic pressure (PASP) may enhance prognosis in heart failure with an adequate ejection fraction. Objective: The aim of the current study is toevaluate the applicability of TAPSE in cases with heart failure and preserved ejection fraction (HFpEF), which is indexed to PASP. Patients and methods: The present study included 75 patients with HFpEF. They were divided into 2 groups depend on the results of 6-minute walking test. Group I included 49 patients with good exercise tolerance and Group II included 36 patients with reduced exercise tolerance. Results: The TAPSE/PASP ratio has a sensitivity of 83.5% and a specificity of 79.3% for detecting individuals with reduced exercise intolerance, with an area under the curve (AUC) of 0.834 (95%CI: 0.753-0.916, P <0.001). Conclusion: A relevant clinical indicator of the length/force relation may be the correlation between longitudinal RV fibre shortening (TAPSE) and developed pressure (PASP), and the ratio of 2 variables may be more reliable than either of the two measures alone in predicting the severity of disease.