In a previous cross-sectional screening study of 5,169 middle and high school students (mean age, 13.1 ± 1.78 yr) in which we estimated the prevalence of high-risk cardiovascular conditions associated with sudden cardiac death, we incidentally detected by cardiac magnetic resonance (CMR) 959 cases (18.6%) of left ventricular noncompaction (LVNC) that met the Petersen diagnostic criterion (noncompaction:compaction ratio >2.3). Short-axis CMR images were available for 511 of these cases (the Short-Axis Study Set). To determine how many of those cases were truly abnormal, we analyzed the short-axis images in terms of LV structural and functional variables and applied 3 published diagnostic criteria besides the Petersen criterion to our findings. The estimated prevalences were 17.5% based on trabeculated LV mass (Jacquier criterion), 7.4% based on trabeculated LV volume (Choi criterion), and 1.3% based on trabeculated LV mass and distribution (Grothoff criterion). Absent longitudinal clinical outcomes data or accepted diagnostic standards, our analysis of the screening data from the Short-Axis Study Set did not definitively differentiate normal from pathologic cases. However, it does suggest that many of the cases might be normal anatomic variants. It also suggests that cases marked by pathologically excessive LV trabeculation, even if asymptomatic, might involve unsustainable physiologic disadvantages that increase the risk of LV dysfunction, pathologic remodeling, arrhythmias, or mural thrombi. These disadvantages may escape detection, particularly in children developing from prepubescence through adolescence. Longitudinal follow-up of suspected LVNC cases to ascertain their natural history and clinical outcome is warranted.

在之前的一项针对5169名中学生和高中生（平均年龄13.1±1.78岁）的横断面研究中，我们估计了与心脏猝死相关的高危心血管疾病的患病率，我们偶然通过心脏磁共振检测到了这一现象（ CMR）959例（18.6％）的左心室非紧致症（LVNC）符合Petersen诊断标准（不紧致：紧致比率> 2.3）。短轴CMR图像可用于其中511个案例（短轴研究集）。为了确定其中有多少是真正的异常，我们根据LV结构和功能变量分析了短轴图像，并在研究结果中应用了除Petersen标准外的3种已发布的诊断标准。根据小梁的左心室重量（Jacquier标准），估计患病率为17.5％。7。基于小梁的左心室体积（Choi准则）为4％，基于小梁的左心室质量和分布（Grothoff准则）为1.3％。由于缺乏纵向临床结果数据或公认的诊断标准，我们对短轴研究集的筛查数据的分析并未明确区分正常病例与病理病例。但是，这确实表明许多情况可能是正常的解剖变异。这也表明，以病理学上过度的左室小梁为特征的病例，即使无症状，也可能涉及不可持续的生理缺陷，从而增加了左室功能障碍，病理性重塑，心律不齐或壁血栓的风险。这些缺点可能会逃避检测，尤其是从青春期前到青春期的儿童。