Department of Ultrasound, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China.
Department of Ultrasound, Shaanxi Xi'an Electric Power Center Hospital, Xi'an, Shaanxi, China.
Biomed Res Int. 2019 Jan 23;2019:3726846. doi: 10.1155/2019/3726846. eCollection 2019.
The thickness and ratio of noncompacted and compacted layers of the left ventricular (LV) myocardium in the normal fetus were investigated by fetal echocardiography. We aimed to investigate the compaction process of the LV myocardium during the normal gestation period and provide reference for echocardiographic diagnosis of a fetus with ventricular myocardium noncompaction. A total of 56 pregnant women in the gestational period of 23-30 weeks were included. Complete fetal echocardiography was performed with system ultrasonographic examination to exclude congenital heart malformation or extracardiac malformation. All 56 fetuses showed normal development. In the short-axis view of the fetal heart, the LV wall was divided into an upper and lower section at the level of the papillary muscle. Each section was then further divided into four segments, namely, anterior, posterior, lateral, and inferior wall. Thus, the LV wall was divided into eight segments. The thickness of the ventricular noncompacted and compacted layers and the ratio of the ventricular noncompacted to compacted layers of these segments at end-systole were measured and calculated. In echocardiography, the fetal LV myocardium is a two-layered structure: the endocardial noncompact myocardium (NC) with higher echo and the epicardium compact myocardium (C) with lower echo. The noncompacted layer is thinner than the compacted layer in the anterior wall, but thicker than the compacted layers in the posterior, lateral, and inferior wall. With respect to the upper and lower sections of the LV myocardium, the noncompacted layer in each segment of the upper section is thinner than that in each segment of the lower section, whereas the compacted layer of the upper section is thicker than that of the lower section. This study suggests that the densification of the fetal LV myocardium occurs gradually from base to apex and from the anterior to lateral, posterior, and inferior walls. This finding aids in further understanding the process of myocardial densification and provides a diagnostic reference for noncompaction of noncompaction cardiomyopathy (NCCM).
应用胎儿超声心动图研究了正常胎儿左心室（LV）心肌的非致密层和致密层的厚度和比例。我们旨在研究正常妊娠期间 LV 心肌的致密化过程，并为心室心肌致密化不全的胎儿超声心动图诊断提供参考。共纳入 56 例妊娠 23-30 周的孕妇。采用系统超声检查进行完整的胎儿超声心动图检查，以排除先天性心脏畸形或心脏外畸形。所有 56 例胎儿均正常发育。在胎儿心脏短轴切面，在乳头肌水平将 LV 壁分为上下两部分。然后，每个部分进一步分为四个节段，即前壁、后壁、侧壁和下壁。因此，LV 壁分为 8 个节段。测量并计算这些节段的心室非致密层和致密层的厚度以及心室非致密层与致密层的比值。在超声心动图中，胎儿 LV 心肌为双层结构：回声较高的心内膜非致密心肌（NC）和回声较低的心外膜致密心肌（C）。在前壁，非致密层比致密层薄，但在后壁、侧壁和下壁，非致密层比致密层厚。就 LV 心肌的上下部分而言，上部各节段的非致密层比下部各节段的非致密层薄，而上部各节段的致密层比下部各节段的致密层厚。本研究表明，胎儿 LV 心肌的致密化从基底到心尖，从前壁到侧壁、后壁和下壁逐渐发生。这一发现有助于进一步了解心肌致密化过程，并为非致密化性心肌病（NCCM）的非致密化提供诊断参考。
