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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.
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Objective To investigate the early changes of left atrial structure and function using echocardiography in obstructive sleep apnea syndrome( OSAS) patients with and without left ventricular hypertrophy(LVH) . Methods Echocardiography was performed in 91 OSAS patients (64 without LVH , 27 with LVH) ,and the results were compared with those from age-matched and gender-matched controls ( n=40) . All subjects were examined with two-dimensional speckle tracking echocardiography ( 2D-STE) to obtain the apical four chamber and two chamber left atrium(LA) strain and strain rate curve image .Systolic strain and strain rate( Ss ,SRs) ,early diastolic strain and strain rate( Se ,SRe) ,late diastolic strain and strain rate(Sa ,SRa) were measured . Phasic LA volumes and empty fractions were calculated . The ratio of peak early diastolic mitral inflow and annulus velocity ( E/e′) was used to estimate left ventricular diastolic function . Results Compared with the control group ,LA volume ,LA stiffness index ,SRa and active empyting fraction ( AEF) increased ,Ss ,SRs ,Se ,SRe ,total empyting fraction ( TEF) and passive empyting fraction ( PEF) decreased in none LVH group ( P < 0 .05) . Importantly ,diastolic function was relatively normal in this subgroup without LVH( P > 0 .05) . Diastolic function decreased in LVH group ,and the changes of left atrial structure and function like above mentioned were more significant .The apnea-hypopnea index (AHI) was found to be negatively correlated with Ss ,SRs ,Se ,SRe ,TEF and PEF . Conclusions OSAS is associated with LA remodeling and dysfunction that occurs before the development of LVH and left ventricular diastolic dysfunction ,and it will be further aggravated along with the development of LVH .
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Objective To investigate the prevalence of impaired glucose-insulin metabolism in obstructive sleep apnea hypopnea syndrome (OSAHS); to examine the relation between severity of OSAHS and impaired glucose metabolism; and to evaluate the effectiveness of continuous positive airway pressure (CPAP) on impaired glucose metabolism.Methods A total of 214 patients who were free of diabetes at baseline underwent both nocturnal polysomnography (PSG),and 2-h oral glucose-tolerance test,insulin and hemoglobin Alc test.CPAP treatment for glucose-insulin metabolism ( + ) was given to OSAHS group after informed consent had been obtained.Results Eighty-eight patients and 17 patients with impaired glucoseinsulin metabolism were found in OSAHS group and the control group respectively.Impaired glucose-insulin metabolism was present in 54.3% of OSAHS group and 32.7% of control group.Logistic regression analysis showed a significant positive correlation with OSAHS ( AHI ≥ 10 times/h ) and impaired glucose-insulin metabolism in all patients (OR = 2.440,95% CI 1.201-4.958 ).Plasma glucose level changes had no significant differences between before and after CPAP treatment (P ＞ 0.05 ).ConclusionOSAHS is associated with a high frequency of impaired glucose metabolism.The relationship between OSAHS and impaired glucose metabolism is independent of obesity.Longest apnea time (LAT) and AHI are important contributors to impaired glucose metabolism in OSAHS patients.Short-term CPAP therapy has no significant improvement on glucose metabolism in patients with OSAHS.
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re serious OSAHS would have more serious and complex coronary artery lesions.