The Evaluation Of Left Ventricular Myocardial Systolic Dysfunction In Patients With Obstructive Sleep Apnea Hypopnea Syndrome Using Three-dimensional Strain Echocardiography

Objective: To evaluate left ventricular myocardial systolic dysfunction in patients with obstructive sleep apnea hypopnea syndrome(OSAHS)with normal left ventricular ejection fraction(LVEF)using three-dimensional strain echocardiography.Methods: The perspective study enrolled 100 patients of OSAHS divided into mild group,moderate group and severe group according to apnea hypopnea index(AHI)while32 healthy cases matched as control group.Routine echocardiography and three-dimensional echocardiographic exam were performed in each group.Two-dimensional LVEF(2D-LVEF)was obtained by Simpson biplane method.The myocardial mechanical parameters such as three-dimensional LVEF(3D-LVEF),global longitudinal strain GLS),global circumferential strain(GCS),global area strain(GAS),global radial strain(GRS),Twist and Torsion based on standard three-dimensional echocardiography were measured using a dedicated imaging workstation.The above parameters between the four groups were compared for significant difference,the ROC curves of each three-dimensional strain parameter were constructed to predict the systolic left ventricle myocardial dysfunction in OSAHS patients.A linear correlationship between AHI and the three dimensional strain parameters was analyzed respectively.Results:1.There was no significant difference of 2D-LVEF,3D-LVEF,Twist and Torsion between each group(P>0.05).2.GLS,GAS and GRS were lower in all OSAHS sub-groups compared to those of control group,and declining along with the severity of OSAHS.(P<0.01 or P<0.05).GCS in severe OSAHS group was lower than that of control group(P< 0.01).3.GLS in severe OSAHS group was lower than that of mild OSAHS group(P< 0.01).GAS in severe OSAHS group was lower than that of mild and moderate OSAHS group(P< 0.01 or P< 0.05).GRS in moderate,severe OSAHS group were lower than those of mild OSAHS group(P<0.05 and P< 0.01),GRS in severe OSAHS group waslower than that of moderate group(P<0.05).4.There was no significant difference between 2D-LVEF and 3D-LVEF in control group,OSAHS group and OSAHS sub-groups(P>0.05).5.GLS showed the highest AUC in predicting the left ventricle myocardial systolic dysfunction for OSAHS patients,which was better than GCS,GAS and GRS.6.There was a moderate positive correlation between GLS and AHI(r=0.663,P<0.01),a mild positive correlation between GCS and AHI(r=0.267,P<0.01),a moderate positive correlation between GAS and AHI(r=0.533,P<0.01),a moderate negative correlation between GRS and AHI(r=-0.567,P<0.01).Conclusion: The left ventricle myocardial systolic function may be impaired subclinically in patients with OSAHS even of normal ventricular ejection fraction and the dysfunction is aggravating with the disease severity.GLS plays as a strong predictor for the left ventricle myocardial systolic dysfunction.The three-dimensional strain echocardiographic technology might be used to detect the myocardial systolic dysfunction quantitatively at the earlier stage of OSAHS patients.