The Comparative Study Of Strain And Strain Rate Between Hypertrophic Cardiomyopathy And Hypertensive Left Ventricular Hypertrophy By Velocity Vector Imaging

Background and Objective It is always difficult to differential nonrepresentative hypertrophic Cardiomyopathy(HCM)from hypertensive left ventricular hypertrophy(HLVH)by conventional ultrasonic cardiography(UCG).Tissue Doppler imaging(TDI)has been applied to study the changes of LV peak systolic strain(ε_sys)and peak systolic strain rate(SR_sys)between HCM and HLVH, however,for the angle-dependence and the poor reproducibility,the results were not satisfied.Recently,STI is a novel method to quantification of regional deformation, allowing visualization and quantification of 2D heart motion independent of borders.The study of the cardiac motion has been performed using STI,and so the success and accurate of measurement ofεand SR were given to evaluate the heart motion.Velocity vector imaging(VVI)is a visual and quantitative method for assessing cardiac mechanics,and the dynamics of cardiac motion,various motion-related parameters are derived from the computed motion.Thus now cardiac motion can be easily ang quickly quatified,and VVI can represent more accurateεand SR.The purpose of this study was to assess the differences ofε_sys,and SR_sys, early diastolic SR(SR_Ed),later diastolic SR(SR_Ld)between HCM and HLVH patients by Velocity Vector Imaging(VVI),so as to distinguish HCM from HLVH. Material and Methods 18 cases with HCM,16 cases with HLVH and 20 age-matched healthy adults were enrolled in the study.ε_sys,SR_sys,SR_Ed,SR_Ldof 18 segments in apical 4,3 and 2-chamber views were measured by VVI.Results It was found thatε_sys,SR_sys,SR_Ed,SR_Ldin control group was -19.97±0.51,-1.19±0.16/s,1.42±0.21/s and 0.64±0.28/s respectively,in HCM group was -14.68±2.09,-0.83±0.47/s,0.63±0.45/s and 0.59±0.12/s respectively, and in HLVH group was -16.52±1.26,-1.12±0.17/s,0.82±0.22/s and 0.80±0.11/s respectively.Compared between any 2 segments within HLVH group, there were no obvious differences inε_sys,SR_sys,SR_Edand SR_Ld(P＞0.05).However, in HCM group,there were statistic differences(P＜0.05).Compared with matched segments in control group,it was found thatε_sysand SR_Edin HCM and HLVH group were decreased(P＜0.05),and all the segments' SR_sysin HCM group were decreased,but in HLVH group it only happened at the hypertrophic region. Compared with matched segments in HCM group,SR_Edof the base and middle segments of posterior and inferior wall,middle segments of anterior septum and anterior wall in HLVH group were bigger than those of HCM group(P＜0.05). Although the thickness of posterior wall in HCM group and HLVH group had no significative difference(P＞0.05),SR_sys,SR_Edin HCM group was obviously smaller than those in HLVH group(P＜0.05).It meant that HCM had more serious harm to heart systolic and diastolic function than HLVH.SR_Ldhad no significative difference among the three groups(P＞0.05).Conclusions In summary,VVI is an adoptable,reliable,and noninvasive method to assess the real-time movement of heart,and it is angle-independence. Assessment of LVε_sys,SR_sys,SR_Edin HCM and HLVH by VVI provides not only peak parameters but also the profile curve,this may facilitate the differential diagnosis of HCM from HLVH.