Multimodal echocardiography for assessing whether left ventricular geometry affects right atrial phasic function in patients with obstructive sleep apnea syndrome: A cross-sectional observational study.

BACKGROUND: Recent studies have shown that right atrial (RA) function are important predictors of cardiovascular morbidity and mortality. However, the study data about RA phasic function in obstructive sleep apnea syndrome (OSAS) patients are scarce, especially based on the left ventricular geometry. So, we aimed to assess the influence of left ventricular geometry on RA phasic function in OSAS patients via a multimodal echocardiographic approach.

METHODS: Total of 235 OSAS patients were enrolled in this cross-section study and underwent complete clinical, polysomnography, and echocardiography examinations. The OSAS patients were divided into four groups based on left ventricular mass index (LVMI) and relative wall thickness (RWT): normal geometry (NG), concentric remodeling (CR), concentric hypertrophy (CH), and eccentric hypertrophy (EH). RA phasic function was evaluated via multimodal echocardiography approach (two-dimensional echocardiography biplane method [2DE]; two-dimensional speckle-tracking echocardiography [2D-STE]; and three-dimensional echocardiography [3DE]). The multiple linear regression analysis was used to determine the relationship between left ventricular geometry and RA phasic function.

RESULTS: The RA volume and indices increased from NG to CR to EH to CH. RA total emptying fraction and RA strain during systole decreased from NG to CR to EH to CH. RA passive emptying fraction and RA strain during early diastole similarly decreased. RA active emptying fraction and RA strain during late diastole also gradually increased similarly. In analyses that adjusted for gender, age, body mass index, systolic blood pressure, apnea-hypopnea index, LVMI, systolic pulmonary artery pressure, and right ventricular free wall thickness, CH was associated with RA reservoir and conduit function via 2DE area-length method, whereas CH and EH were associated with RA reservoir and conduit function via 2D-STE and 3DE method. Further, CH was associated with RA booster pump function via 2DE area-length method, 2D-STE, and 3DE method.

CONCLUSION: The RA volumes and phasic function varied with left ventricular geometry via multimodal echocardiography approach. CH had the apparent negative effect on RA phasic function.