Sex Differences in Echocardiographic Measures of Right Ventricular Function and RV–PA Coupling

BACKGROUND: Right-ventricular-pulmonary arterial (RV-PA) coupling reflects the relationship between RV contractility and pulmonary vascular load and is a key determinant of cardiopulmonary performance. The tricuspid annular plane systolic excursion-to-pulmonary artery systolic pressure ratio (TAPSE/sPAP) provides a noninvasive estimate of RV-PA coupling. However, sex-related differences in its relationship with pulmonary pressure remain unclear. OBJECTIVE: To evaluate sex-related differences in pulmonary pressure, diastolic load, RV systolic function, and RV-PA coupling. METHODS: We conducted a retrospective analysis of echocardiographic data from 243 adults. Pulmonary pressure was assessed using systolic (sPAP), mean (mPAP), and diastolic (dPAP) measurements. RV function was evaluated using TAPSE and RV S' velocity, and diastolic load using the E/e' ratio and estimated PCWP. RV-PA coupling was estimated using TAPSE/sPAP and RV S'/sPAP ratios. Categorical variables (n = 193) were analyzed using Fisher's exact test, and continuous variables using correlation and regression analyses. RESULTS: Females exhibited a higher prevalence of abnormal sPAP (p = 0.038) and E/e' (p < 0.001), whereas males had a higher prevalence of abnormal mPAP (p < 0.001) and PCWP (p = 0.0016). Abnormal RV S' was more frequent in females (p = 0.0178). TAPSE and RV S' were inversely correlated with pulmonary pressure (ρ ≈ -0.45 to -0.55, p < 0.001). Regression analysis demonstrated a significant sex × pulmonary pressure interaction. CONCLUSIONS: Sex-related differences were observed in pulmonary pressure indices and RV systolic parameters; however, no significant difference was found in the primary RV-PA coupling index. These findings are associative and hypothesis-generating.