三维斑点追踪技术联合常规超声心动图评价肥厚型心肌病肌小节突变携带者左心室功能的早期改变

Assessment of left ventricular dysfunction of sarcomere mutation carriers in hypertrophic cardiomyopathy by three-dimensional speckle tracking imaging combined with conventional echocardiography

目的应用三维斑点追踪技术(3D-STI)与常规超声心动图评价肥厚型心肌病(HCM)亲属中携带肌小节基因突变但无左室肥厚者的左心室功能特征,为早期诊断提供影像学依据。方法选取2013年2月至2017年4月在空军军医大学西京医院肥厚型心肌病诊治中心就诊的HCM患者亲属中携带肌小节基因突变但无左心室肥厚者91例为基因阳性表型阴性组(G+/P-组);同时纳入性别年龄匹配的未携带突变基因且无左室肥厚的亲属100例,即基因阴性表型阴性(G-/P-组)作为对照。对所有入选研究对象行3D-STI及常规超声分析,比较两组差异并评估超声参数对肌小节基因突变携带者的诊断效能。结果与G-/P-组相比,G+/P-组左房前后径(LAD)增大,等容舒张时间(IVRT)延长,E/e′增大,e′降低,三维整体纵向和径向应变(GLS和GRS)降低(均P<0.05);ROC曲线分析显示,GLS≤19.9%(曲线下面积0.861,敏感性61.4%,特异性98.5%)和IVRT≥75.5 ms(ROC曲线下面积0.762,敏感性61.4%,特异性72.6%)对亲属携带肌小节基因突变的诊断效能最佳(均P<0.05)。结论HCM亲属中,携带肌小节基因突变者在未出现左室肥厚时就已经出现左室舒张功能减低和左室纵向、径向收缩功能减退,且GLS和IVRT对携带肌小节基因突变的HCM亲属诊断效能最佳。

Objective To explore the value of three-dimensional speckle tracking imaging(3D-STI)and conventional echocardiography in evaluating left ventricular function characteristics of sarcomere mutation carriers in hypertrophic cardiomyopathy.Methods Totally 91 subjects with sarcomere mutations in family HCM but without left ventricular hypertrophy(G+/P-group),and 100 normal family members with gender and age matched as the control group(G-/P-group)were enrolled from the center of hypertrophic cardiomyopathy of Xijing Hospital affiliated to the Air Force Military Medical University from February 2013 to April 2017.They all received the comprehensive evaluation of 3D-STI and conventional echocardiography.The ultrasonic paramaters between the two groups were compared.And the diagnostic performance of these paramaters with sarcomere mutations was evaluated.Results Compared with the G-/P-group,the G+/P-group had larger left atrial diameter(LAD),longer left ventricular isovolumic relaxation time(IVRT),reduced mitral annular systolic velocity(e′),elevated E/e′ratio,as well as impaired left ventricular global longitudinal and radial strain(GLS and GRS)(P<0.05).Moreover,the GLS≤19.9%(AUC 0.861,sensitivity 61.4%,specificity 98.5%)and IVRT≥75.5 ms(AUC 0.762,sensitivity 61.4%,specificity 72.6%)showed the best diagnostic performance with sarcomere mutations(P<0.05).Conclusions In HCM family members,the sarcomere mutations carriers without left ventricular hypertrophy exhibit impaired left ventricular diastolic function,reduced longitudinal and radial systolic function.Moreover,the GLS and IVRT show the best diagnostic performance for those with sarcomere mutations.