Assessment Of Left Atrial Structure And Function In Patients With Hypertension By Three-dimensional Speckle Tracking Imaging

ObjectiveHypertension can cause left ventricular diastolic dysfunction, and further lead to the changes of left atrial(LA) structure and function. Three-dimensional speckle tracking imaging(3D-STI) is a kind of newly development technique based on three-dimensional echocardiography and speckle tracking imaging, it can identify and track the motion of myocardial speckle in three-dimensional space, and provide a more accurate reflection of the changes of the myocardial motion. The purpose of the study is to evaluate LA structure and function in patients with hypertension by3D-STI.MethodsA total of 78 outpatients treated without antihypertensive drugs for at least 1 year were included in the study, which were divided into dippers and nondippers. 43 normal subjects were selected as the controls.The related 3D-STI parameters include: radial peak strain(RPS), longitudinal peak strain(LPS), circumferential peak strain(CPS) and area peak strain(APS) of LA16 segments; LA global longitudinal peak strain(GLPS), global radial peak strain(GRPS), global circumferential peak strain(GCPS) and global area peak strain(GAPS); the time of LA global peak radial strain(GTRS), longitudinal strain(GTLS),circumferential strain(GTCS) and area strain(GTAS); the standard deviation of time to peak longitudinal strain(TLS-SD), radial strain(TRS-SD), circumferential strain(TCS-SD) and area strain(TAS-SD).The correlationship between LA ejection fraction(LAEF) and LA global peak strains was analyzed. Area under the receiver operating characteristic curve(ROC)was also measured.Results1. Compared with controls, the most LA segments of APS, LPS, CPS and some segments of RPS were significantly reduced, and those values in nondippers were lower when compared with dippers(all P <0.05).2. The LAEDV and LAESV values were higher in the hypertensive patients than those in normal volunteers, and both of them in nondippers were greater when compared with dippers(all P<0.05). Compared with controls, GRPS, GLPS, GCPS,GAPS and LAEF in both dippers and nondippers were significantly decreased, and all the parameters decreased significantly through the comparison of nondippers with dippers(all P<0.05).3. Compared with controls, GTRS, GTLS, GTCS and GTAS in both dippers and nondippers were significantly increased, and all the parameters increased significantly through the comparison of nondippers with dippers(all P<0.05). The TLS-SD, TRS-SD, TCS-SD and TAS-SD were higher in the hypertensive patients than those in normal volunteers, and both of them in nondippers were greater when compared with dippers(all P<0.05).4. The Pearson correlation analysis was used to assess the correlation between LA global peak strains and LAEF. In the correlation analysis, GLPS, GRPS, GCPSand GAPS were correlated positively with LAEF(r=0.49, 0.21, 0.32 and 0.54,respectively, all P<0.05).5. The area under the curve(AUC) of GLPS, GRPS, GCPS and GAPS were0.900, 0.765, 0.796 and 0.876, respectively. GLPS provided the highest AUC for discriminating hypertension.ConclusionLA strains in hypertensive patients were significantly decreased, and associated with an adverse cardiac injury and impaired LA mechanical function. 3D-STI enables to measure the changes of myocardial deformation early in patients with hypertension and reflects the severity. Taken together, 3D-STI is a simple workable technique to measure LA structure and function in hypertensive patients, which is available in clinical applications.