摘要目的 应用分层应变技术评估主动脉瓣二瓣化(BAV)患者左室收缩功能的改变.方法30例BAV患者根据瓣膜病变情况分为瓣膜功能正常(NF )组(10例)和瓣膜功能异常(N‐NF )组(20例) ,选取20例健康志愿者作为对照组.应用 GE Vivid E9和 EchoPac工作站的分层应变技术,比较左室各层及整体全层的纵向和环向应变参数.结果 N‐NF 组、 NF 组与对照组左室射血分数(LVEF)差异无统计学意义(P ＞ 0.05),均在正常范围之内[ (63.3±7.1)%, (64.6±6.2)%, (65 .3 ± 3 .9)%].对照组及BAV组左室心肌各层及整体全层纵向应变(LS)及圆周应变(CS)均由内层向外层逐渐递减. N‐NF组和NF组内层和外层心肌的LS低于对照组[内层: (－21 .19 ± 3 .12)% 对(－23.06±2.07)% 对(－25.53±2.51)%;外层: (－16.08±2.68)% 对(－18.85±2.12)% 对(－20 .72 ± 2 .28)%] ,差异有统计学意义(均 P ＜0 .05) .与对照组比较, NF组各层心肌及整体全层心肌CS 、中层及整体全层心肌LS差异无统计学意义(均 P ＞0 .05) . N‐NF组中层、外层心肌及整体全层心肌CS [ (－16.78±3.65)% 对(－11.40±3.78)% 对(－15.83±2.61)%]及 LS [ (－18.34± 2 .85)% 对(－16 .08 ± 2 .68)% 对(－18 .51 ± 2 .86)%]较NF组[CS : (－19 .57 ± 2 .9)% 对(－13 .43 ± 2.19)% 对(－20.03±3.04)%;LS: (－21.38±2.05)% 对(－18.85±2.12)% 对(－21.09± 2.03)%]及对照组[CS: (－21.63±3.01)% 对(－14.34±2.55)% 对(－21.48±2.16)%;LS:(－22 .18 ± 2 .30)% 对(－20 .72 ± 2 .28)% 对(－22 .89 ± 2 .30)%]减低,差异有统计学意义(均 P ＜0 .05) .结论 LVEF正常的BAV患者左室收缩功能已经发生改变,维持正常的瓣膜功能对于防止心肌损害的发展至关重要,左室内层和外层LS可以更敏感地发现BAV患者早期左室心肌的收缩功能改变.

abstractsTo quantitatively evaluate left ventricular ( LV ) systolic function in bicuspid aortic valve ( BAV ) using layer‐specific strain ( LSS ) . Methods T hirty BAV patients were divided into normal function ( NF) group ( 10 cases) and non‐normal function ( N‐NF) group ( 20 cases) based on aortic valvular lesion types ,and 20 healthy volunteers were taken as control group . Longitudinal strain( LS ) and circumferential strain ( CS) of three‐layer myocardium and full thickness myocardium were assessed using layer‐specific speckletracking imaging ,available by GE Vivid E 9 and EchoPac workstation . Results There was no significant difference in left ventricular ejection fraction( LVEF) among the N‐NF group ,NF group and control group ( P ＞ 0 .05 ) ,all of them within the normal range [ ( 63 .3 ± 7 .1 )% ,( 64 .6 ± 6 .2 )% , ( 65 .3 ± 3 .9)% ] . It showed a gradient decrease from the endocardium to the epicardium in both control and BAV group . LS of endocardium ( LSendo ) and LS of epicardium ( LSepi) in N‐NF group and NF group were significantly reduced compared with those in control group ( P ＜0 .05) [ LSendo :( －21 .19 ± 3 .12 )%vs ( －23 .06 ± 2 .07 )% vs ( －25 .53 ± 2 .51 )% ;LSepi :( －16 .08 ± 2 .68 )% vs ( －18 .85 ± 2 .12 )% vs ( －20 .72 ± 2 .28)% ] . Compared with control group ,there was no significant difference in NF group in CS of the three‐layer myocardial and full‐thickness myocardium as well as the LS of the w hole medial myocardial layers and full‐thickness ( P ＞ 0 .05 ) . Compared with NF group [ CS :( －19 .57 ± 2 .9 )% vs ( －13 .43 ± 2 .19)% vs ( －20 .03 ± 3 .04)% ;LS :( －21 .38 ± 2 .05)% vs ( －18 .85 ± 2 .12)% vs ( －21 .09 ± 2 .03)% ] and control group[ CS :( －21 .63 ± 3 .01)% vs ( －14 .34 ± 2 .55 )% vs ( －21 .48 ± 2 .16 )% ;LS :( －22 .18 ± 2 .30 )% vs ( －20 .72 ± 2 .28 )% vs ( －22 .89 ± 2 .30 )% ] , CS [ ( －16 .78 ± 3 .65 )% vs ( －11 .40 ± 3 .78 )% vs ( －15 .83 ± 2 .61 )% ] and LS [ ( －18 .34 ± 2 .85 )% vs ( －16 .08 ± 2 .68 )% vs ( －18 .51 ± 2 .86)% ] of middle myocardium ,epicardial myocardium and full‐thickness myocardium in N‐NF group were decreased significantly ( P ＜ 0 .05 ) . Conclusions It is essential to maintain normal valvular function to prevent the progress of myocardial deterioration . LSendo and LSepi can be used to sensitively identify early left ventricular systolic dysfunction in BAV patients with normal LVEF .