Early changes of left ventricular function in patients with obstructive sleep apnea syndrome / 中国医学影像技术

ABSTRACT

Objective To investigate the changes of left ventricular systolic and diastolic function before left ventricular morphologic changes in obstructive sleep apnea syndrome (OSAS) patients.Methods A total of 111 OSAS patients were divided into left ventricular hypertrophy (LVH) group (n=29) and non-LVH group (n=82).Meanwhile,50 healthy subjects were enrolled as normal control group.Routine echocardiography and two-dimensional speckle tracking imaging (2D-STI) were performed.The differences of conventional echocardiography and 2D-STI parameters were compared among the three groups.The correlations between echocardiography and clinical parameters were analyzed.Results Compared with those of the other 2 groups,left ventricular mass index (LVMI),diastolic thickness of interventricular septum (IVST),diastolic ventricular posterior wall thickness (PWT),left ventricular internal diastolic dimension (LVIDd),the ratio between early diastolic peak velocity of mitral valve and early diastolic velocity of mitral annular (E/e') and left atrial volume index (LAVI) increased (all P＜0.05),and mitral annular early diastolic velocity (e') at interventricular septum and lateral wall decreased in LVH group (all P＜0.05).The mitral annular systolic velocity (s') in LVH group was less than that in normal control group (P =0.013).Compared with those of the other 2 groups,left ventricular global longitudinal systolic strain (S) and early diastolic strain rate (SRE) decreased (all P＜0.05),and the ratio of early diastolic peak velocity of mitral valve to SRE (E/SRE) increased in LVH group (both P＜0.05).Compared with normal control group,systolic strain rate (SRS) decreased in LVH group (P=0.001).S,SRS,SRE in non-LVH group were less than those in normal control group (all P＜0.05),and E/SRE was higher than that in normal control group (P＜0.001).S,E/SRE were independently associated with apnea hypopnea index (both P＜0.05).LVMI was independently associated with mean arterial oxygen saturation (β =-0.299,t =-3.273,P =0.001).Conclusion OSAS can affect the structure and functions of left ventricular independently.The systolic and diastolic functions of left ventricular have been impaired before morphology changed.