Luo Xiu-Xia, Zhu Yongsheng, Sun Yiqian, Ge Quanrong, Su Jin, So Hung-Kwan, Yam Man-Ching, Fang Fang
Department of Ultrasonography, Shenzhen Hospital, Southern Medical University, Shenzhen, China.
Department of Paediatrics and Adolescent Medicine, The University of Hong Kong, Hong Kong, China.
Front Pediatr. 2018 Jun 5;6:167. doi: 10.3389/fped.2018.00167. eCollection 2018.
Masked hypertension (MH) is not uncommon in the youth and may increase risks of long-term cardiovascular impairment. However, little is known about the subclinical heart damage in this group of patients. Currently, 3-layer speckle tracking imaging based on two-dimensional echocardiography is feasible to detect the early signs of myocardial damage. We therefore aimed to investigate whether subtle changes of cardiac function occurred in the young MH patients by using advanced quantification with layer-specific speckle tracking. A total of 40 adolescents with MH (age 18 ± 3 years, 73% males) and 40 age-, gender-, race-, and height-matched normotensive volunteers were enrolled in our study. MH was defined as one or more of the ambulatory blood pressure (BP) parameters (24-h, daytime and night-time average BPs) higher than ≥ 95th percentile for gender and height according to the local reference. Both comprehensive two-dimensional echocardiography with layer-specific strain analysis and 24-h ambulatory BP monitoring were performed. Longitudinal strain and circumferential strain in endocardial, mid-myocardial, and epicardial layers were determined accordingly with the dedicated software (EchoPAC software version 201, GE Healthcare, Horten, Norway). Compared with normotensive controls, youths with MH had higher ambulatory pulse rate and left ventricular mass index, and were more obese. Interestingly, similar ventricular volumes and ejection fraction were observed in the study groups, but further analysis with layer-specific strains revealed that endocardial and mid-myocardial longitudinal and circumferential mechanical function were decreased in the young MH subjects when compared to normotensive individuals (all < 0.05). However, there were no difference regarding radial strain and apical rotation derived from traditional speckle tracking analysis. Subclinical change of LV mechanic function assessed by layer-specific speckle tracking is present in youth with MH despite considered as normal with conventional ways.Thus, MH in youth should be monitored closely instead of labeling as an entirely benign entity.
隐匿性高血压（MH）在年轻人中并不少见，可能会增加长期心血管损害的风险。然而，对于这类患者的亚临床心脏损伤知之甚少。目前，基于二维超声心动图的三层斑点追踪成像可用于检测心肌损伤的早期迹象。因此，我们旨在通过使用具有层特异性斑点追踪的先进量化方法，研究年轻MH患者的心脏功能是否发生细微变化。我们的研究共纳入了40名患有MH的青少年（年龄18±3岁，73%为男性）和40名年龄、性别、种族和身高匹配的血压正常志愿者。根据当地参考标准，MH被定义为动态血压（BP）参数（24小时、白天和夜间平均血压）中的一项或多项高于性别和身高的≥95百分位数。同时进行了具有层特异性应变分析的全面二维超声心动图检查和24小时动态血压监测。使用专用软件（EchoPAC软件版本201，通用电气医疗集团，挪威霍滕）相应地确定心内膜、心肌中层和心外膜层的纵向应变和圆周应变。与血压正常的对照组相比，患有MH的年轻人有更高的动态脉搏率和左心室质量指数，且更肥胖。有趣的是，在研究组中观察到了相似的心室容积和射血分数，但对层特异性应变的进一步分析显示，与血压正常的个体相比，年轻MH受试者的心内膜和心肌中层纵向及圆周机械功能降低（均P<0.05）。然而，传统斑点追踪分析得出的径向应变和心尖旋转方面没有差异。尽管用传统方法认为正常，但通过层特异性斑点追踪评估的左心室机械功能的亚临床变化在患有MH的年轻人中存在。因此，对于年轻人中的MH应密切监测，而不应将其视为完全良性的情况。
