Atrial Mechanical Function Assessed By Doppler Tissue Imaging In Hypertension Patients

Objective: To investigate atrial mechanical function in hypertension patients by tissue doppler imaging(TDI),to evaluate the association of left ventricular geometric model and diastolic function with atrial mechanical function,and to analyze the influential factors of atrial mechanical function in hypertension patients.Methods: The study included 106 hypertension patients (mean age 61.6+/-12.8 years) and a control group of 86 sex- and age-matched healthy individuals. Patients were divided into four groups according to Ganau categories of echocardiography:normal left ventricle geometric model group(NG group, n=32 ),concentric remodeling group(CR group,n=23), concentric hypertrophy(CH group,n=30), eccentric hypertrophy group(EH group,n=21). Patients were divided into three groups according to stage of left ventricular diastolic dysfunction:normal filling pattern group(NF group,n=21),impaird relaxation group(IR group,n=67),pseudonormal/restrictive filling group(PN/R group,n=18).All study participants underwent complete standard echocardiography (2D, M-mode, pulsed Doppler) and a Color Doppler myocardial imaging study. Left atrial diameter and left atrial ejection force were acquired by standard echocardiography. The peak regional atrial contraction velocities Am(VA) at the mid levels of the LA(VA-LA), inter-atrial septum(VA-IAS) and the RA(VA-RA) after the onset of p wave of electrocardiogram were measured . Using the onset of p wave in ECG as the reference point,the time to the onset(TO) of atrial contraction of the LA(TO-LA), inter-atrial septum (TO-IAS)and the RA (TO-RA)was measured .The difference of TO-IAS and TO-RA(â–³TO-RA), the difference of TO-LA and TO-IAS(â–³TO-LA)and the difference of TO-LA and TO-RA(â–³TO)were calculated.Result: 1 LAD,LAEF,VA-LA,VA-RA were higher in the hypertension patients group than the the control group(P<0.05~0.01);. LAD,LAEF,VA-LA in the NG group, CR group,CH group,EH group were higher than the control group(P<0.05~0.001), in the CR group higher than the NG group(P<0.05), in the CH group,EH group higher than the NG group,CR group(P<0.05~0.001),between the CH group and the EH group showed insignificant changes(P>0.05);VA-RA in the CH group,EH group was significantly higher than the control group(P<0.001)2.â–³TO was longer in the hypertension patients group than the the control group(P<0.001);Compared with various geometric model group,â–³TO in the CR group,CH group,EH group was longer than the control group(P<0.05~P<0.001), in the CH group,EH group longer than the NG group(P<0.05),between the CH group and the EH group,between the NGgroup and the CR group showed insignificant changes(P>0.05);Compared with various left ventricular diastolic dysfunction,;â–³TO in the control group,CR group,CH group,EH groupwas longer in turn, the difference of PN/R group and control group,NF group showed significant changes(P<0.01~P<0.001), the difference of IR group and control group showed significant changes(P<0.05). 3 LAD was positively correlated with BMI,age,systole pressure,IVSd,LVMI,IVRT,EDT and was negatively correlated with E/A.LAEF,VA-LA were positively correlated with age,systole pressure,IVSd,LVMI,IVRT,EDT and was negatively correlated with E/A.. A strong correlation was detected among LAD,LAEF,VA-LA.Conclusion:1 Left atrial structure and function have altered before left ventricle hypertrophy,especially in hypertrophy geometric model.2 Right atrial function is enhanced in left ventricle hypertrophy geometric model, right atrial function may be relative with left ventricle hypertrophy.3 There is atrial asynchrony in hypertension patients, especially in hypertrophy geometric model .with the diastolic function dysfunction, atrial asynchrony is enhanced.4 Left Ventricular Mass Index, age, systole presure and diastolic function is relative with left atrial enlarge and left atrial function alteration.5 Assessment of atrial mechanical function by DTI is feasible in hypertension patients..