Abstract: Objective To explore the relationship between phase angle (PA) and cardiac structure and function in patients with maintenance hemodialysis (MHD).  Methods  A total of 109 patients undergoing MHD in Department of Nephrology, The Affiliated Hospital of Chengde Medical College from January 2023 to June 2023 were included in this study. General information, biochemical results, cardiac ultrasonography, nutritional score, and PA from body composition analyses were recruited. Patients were then divided into low PA group (54 patients) and high PA group (55 patients). Clinical characteristics were compared between the two groups. Univariate and multifactorial regression analyses were used to analyze the differences in cardiac structure and function between the two groups.  Results  The left atrium diameter (t=2.625, P=0.010), early diastolic mitral orifice peak velocity/early diastolic mitral ring motion velocity (E/E') ratio (Z=2.036, P=0.042), cardiac valve insufficiency (χ2=4.650, P=0.031) and cardiac valve calcification ratio (χ2=12.660, P＜0.001) were significantly increased in low PA group as compared with those  in high PA group. Univariate linear regression showed that low PA was correlated with left atrium diameter and E/E' ratio (β=3.086 and 2.789, P=0.010 and 0.028). Multifactor linear regression showed that low PA was independently correlated with left atrium diameter (β=3.404, P=0.009). Univariate logistic regression found that the risks of cardiac valve insufficiency (OR=2.442, 95% CI：1.075～5.546, P=0.030) and cardiac valve calcification (OR=4.190, 95% CI：1.870～9.393, P＜0.001) increased with low PA. Multivariate logistic regression found that low PA was the independent risk factor for cardiac valve calcification (OR=2.770, 95% CI：1.042～7.364, P=0.041).  Conclusion   Low PA is associated with enlarged left atrium diameter, increased E/E' ratio, cardiac valve calcification and cardiac valve insufficiency in MHD patients, and is the independent risk factor for left atrium diameter and cardiac valve calcification in MHD patients.

Key words: Phase angle, Bioelectrical impedance analysis, Maintenance hemodialysis, Cardiac structure and function