[The role of three-dimensional speckle tracking imaging derived parameters on predicting outcome of hypertrophic cardiomyopathy patients with MYH7 mutations].

Objective: To evaluate the cardiac functional changes in hypertrophic cardiomyopathy(HCM) patients with β-myosin heavy chain gene (MYH7) mutations by three-dimensional (3D) speckle tracking imaging(3D-STI) and conventional echocardiography modalities, and then to explore the potential predictors of adverse cardiovascular events in these patients. Methods: A consecutive series of 192 HCM patients admitted in our center from October 2014 to October 2016 were genetically screened to identify MYH7 mutations in this retrospective study. A total of 43 HCM patients with MYH7 mutations were enrolled. The patients were divided into events group(n=13) and no event group(n=30) according to the presence or absence of adverse cardiovascular events(primary and secondary endpoints). All patients were followed up to January 2019 after comprehensive evaluation of 3D-STI, two-dimensional and Doppler echocardiography. The adverse cardiovascular events were recorded. Results: The median follow up time was 1 012 (812, 1 330) days. During follow-up, 13 patients (30.2%) reached endpoints: 6 cases of the primary endpoints(2 cases of sudden cardiac death(SCD), 3 cases of survival after defibrillation, and 1 case of appropriate implantable cardioverter-defibrillator(ICD) discharge); 7 cases of the second endpoints(5 cases of heart failure hospitalization, 1 case of syncope and cardioversion due to supraventricular tachycardia, and 1 case of end-stage HCM). Patients with adverse cardiovascular events had higher prevalence of syncope and risk of SCD, enlarged left atrial volume index(LAVI) and reduced 3D left ventricular global longitudinal train (3D-GLS), as compared to those without adverse events(all P<0.05). The multivariate Cox regression analysis showed that reduced 3D-GLS(HR=0.814, 95%CI 0.663-0.999, P=0.049) was an independent predictor for adverse cardiovascular events. The cutoff value of 3D-GLS≤13.67% was linked with significantly increased risk of adverse cardiovascular events in this patient cohort(AUC=0.753, 95%CI 0.558-0.948, sensitivity 86%, specificity 69%, P<0.05). The Kaplan-Meier analysis indicated that the patients with the 3D-GLS≤ 13.67% faced higher risk of death than those with 3D-GLS>13.67%. Conclusion: 3D-GLS is useful on predicting adverse cardiovascular events in HCM patients with MYH7 mutations.目的： 采用三维斑点追踪（3D-STI）技术联合二维和多普勒超声对携带β-肌球蛋白重链基因（MYH7）基因突变的肥厚型心肌病（HCM）患者心功能特征进行全面评估，以期找到可预测此类患者不良心血管事件的超声指标。 方法： 该研究为回顾性研究。连续入选2014年10月至2016年10月在西京医院肥厚型心肌病诊治中心就诊的携带MYH7基因突变的成人HCM患者43例，根据有无终点事件发生分为2组，即终点事件组（n=13）和无终点事件组（n=30）。收集入选患者的一般临床资料、超声心动图检测结果及随访结果，记录终点事件的发生情况。终点事件：一级终点事件包括心脏性猝死（SCD），心脏骤停抢救存活或植入埋藏式心脏除颤器（ICD）适当放电；二级终点事件包括急性心梗，因心力衰竭住院，血栓栓塞，室上性心律失常致血流动力学不稳定，终末期HCM。 结果： 43例患者均完成随访，随访时间1 012（812，1 330）d。13例（30.2%）患者发生终点事件，其中6例（14.0%）发生一级终点事件（SCD 2例、心脏骤停抢救存活3例、ICD适当放电1例），7例（16.3%）发生二级终点事件（因心力衰竭住院5例、室上性心动过速致晕厥复律1例、终末期HCM 1例）。与无终点事件组比较，终点事件组患者5年SCD风险评分较高（P<0.05），发生晕厥的患者比例较高（P<0.05），左心房容积指数（LAVI）较大（P<0.05），左心室三维整体纵向应变（GLS）绝对值较低（P<0.05）。校正年龄、性别后多因素Cox回归分析结果显示，GLS是携带MYH7基因突变的HCM患者发生不良心血管事件的独立预测因素（HR=0.814，95%CI 0.663~0.999，P=0.049）。受试者工作特征（ROC）绝对值曲线评估结果显示，GLS绝对值≤13.67%的患者更易发生不良心血管事件（AUC=0.753，95%CI 0.558~0.948，P<0.05），敏感度为86%，特异度为69%。Kaplan-Meier生存曲线结果进一步显示，GLS绝对值≤13.67%的HCM患者无终点事件生存率明显低于GLS绝对值>13.67%的患者（P<0.05）。 结论： 3D-STI指标GLS可作为携带MYH7基因突变的HCM患者不良心血管事件的预测指标。.