Investigation On Left Ventricular Myocardial Systolic Synchrony In Hypertensive Patients With Diastolic Dysfunction

Backgrounds and ObjectivesLeft ventricular systolic dyssynchrony was often found in patients with systolic heart failure but it is reported recently to be found in patients with diastolic heart failure.Hypertension is one of the main reasons of diastolic heart failure.The assessment of left ventricular systolic dyssynchrony of hypertensive patients with diastolic dysfunction is important in the early detection of cardiac dysfunction and investigation of the hemodynamic mechanism in progression of heart failure.This study aims to investigate myocardial multi-dimensional systolic synchrony of hypertensive patients with high filling pressure by two dimensional strain echocardiography and tissue synchronization imaging and to discuss left ventricular systolic synchrony in hypertensive patients with diastolic dysfunction.MethodsOne hundred hypertensive patients with diastolic dysfunction (HT-HFP)(male 62, female 38, average age 57.99±10.67 years) except the patients with valvular heart disease, cardiomyopathy and myocardial infarction were studied.Hypertensive patients were diagnosed by 2005 Guideline for the Management of Hypertension and diastolic dysfunction with high filling pressure was diagnosed by 2007 ESC and 2009 ASE .37 age- and gender- matched normotensive healthy volunteers (male 18, female 19, average age 54.19±8.0 years) as the control group were studied. Then the patients were divided into two groups according to left ventricular mass index(LVMI): non-left ventricular hypertrophy (group NLVH,44 cases), left ventricular hypertrophy (group LVH, 56 cases).Echocardiographic examination was performed to acquire parameters including LV diameter, wall thickness, left atrial size, LV ejection fraction (LVEF), transmitral diastolic inflow velocities(E, A), mitral annuluar systolic,early and late diastolic velocities(Sa, Ea, Aa) .The dynamic images stored in hardware were analysised by EchoPAC 7.0 workstation offline and left ventricular synchrony parameters were achieved..The left ventricular synchrony parameters included 2-dimensional strain echocardiography(2DSE)parameters and tissue synchronization imaging (TSI)parameters .The time from the onset of QRS complexes to systole peak strain from the longitudinal,radial vectors(Tls,Trs)was recorded and measured using 2DSE respectively.The mean and the standard deviation of Tls,Trs of 12 segments were calculated as indicator of LV systolic synchrony.Time to peak systolic velocity (Ts) of 12 segments was obtained in apical 4-chamber view,apical 2-chamber view and long axis of left ventricular view using TSI. The mean,standard deviation and the max difference of Ts were calculated.These parameters were used to assess the systolic synchrony of left ventricle.Results1. LV mass and left atrial volume increased in the HT-HFP patients and left ventricular ejection fraction(LVEF) and Sa slightly decreased [(HT-HFP: 62.12±6.31)%vs(NC:64.08±4.39)%,p<0.05;(HT-HFP :0.05±0.01)vs (NC:0.06±0.01),p<0.05]. Those parameters of LVH group was lower than those of NLVH group.2. Both 2DSE and TSI can show that the time to peak of longitudinal strain or velocity and the longitudinal synchrony index of these times in the HT-HFP group were higher than those in NC group(all p <0.05),and no significant difference was found between the LVH group and the NLVH group(p>0.05).The longitudinal dyssynchrony index had negative correlation with Sa(p <0.05)and positive correlation with LVMI(r=0.249,p<0.05).3. Prolonged the mean of time to LV radial strain in the HT-HFP patients(p <0.05),but no significant difference was found between the LVH group and the NLVH group(p>0.05).Conclusions1. Left ventricular longitudinal systolic dyssynchrony was found in hypertensive patients with diastolic dysfunction and with the increase of left ventricular hypertrophy while LVEF is preserved, which might relate to the subendocardial myocardial ischemia of left ventricle.2. Prolonged time to peak of LV radial stain but not systolic dyssynchrony was detected in hypertensive patients with diastolic dysfunction, which might to some degree contribute to the preserved LVEF.