一名5个月大的男婴因发热和心悸住进了我院儿科心脏科。他有一个8岁健康的亲妹妹。心电图显示房性心律失常(房性早搏和房颤),伴T波从V1到V3倒置,导联V4-V6低平(图1A)。胸骨旁左心室短轴切片二维超声心动图(2D TTE)显示中后室间隔明显不对称肥厚(最大间隔厚度为13 mm;无间隔壁比= 4.3;图1 b)。胸骨旁4腔2D TTE切片显示增厚的室间隔位于基底区(图1C)。增厚部分的超声回声明显高于正常心肌组织。心肌增厚和回声,就像鸡蛋中含有的蛋黄,在心脏周期中观察到变形(视频1)。这种不均一的回声使人怀疑是心脏肿块,而不是普通的肥厚性心肌病。未见流出道梗阻和瓣环狭窄(视频2)。左心室扭曲,二维和多普勒显示轻度二尖瓣前瓣脱垂和轻度二尖瓣返流。 The cardiac function of the patient was normal. To provide a more accurate evaluation of the local interventricular septum hypertrophy and tissue characterization, cardiac magnetic resonance imaging (MRI) using a 1.5 Tesla scanner was subsequently performed. Because the patient was very young, and his kidney function was incapable of gadolinium, a cardiac MRI was performed without contrast enhanced imaging. A cine (steady-state free precession) view of the MRI confirmed the regional myocardial thickening (Figure 1D), which had signal characteristics similar to the remaining myocardium on T1-weighted fast spin-echo and fat suppression images (Figure 1E). Moreover, it appeared with mild hypo-intensity on T2-weighted fast spin-echo images (Figure 1F). These typical MRI characterizations permitted ruling out the presence of hypertrophic cardiomyopathy and allowed a confident diagnosis of rare cardiac fibroma (Videos 3,4). Surgical resection was deemed not necessary at the time because of the absence of clinical indications (i.e., severe arrhythmias, hemodynamic or respiratory compromise, or a significant risk of systemic embolic events) [4]. In addition, the patient had endomyocardial fibro elastosis syndrome when he was 1-year-old, which was cured. He was also found to have a black verrucous nevus in the facial, neck, and trunk areas from birth. Oral antiarrhythmic agent therapy was continued under close echocardiographic and rhythmic monitoring with follow-up evaluation at 5 years. During these years, echocardiographic features of the patient in this case were unchanged and clinical symptoms of the heart were stable.
纤维瘤被认为是儿童第二大最常见的原发性心脏壁内肿瘤,而横纹肌瘤是第一常见的[6]。超声心动图和MRI特征可为上述肿瘤的鉴别提供重要参考。纤维瘤是典型的单发、高度屈光、界限清晰的左心室壁内肿块,多数复发和生长的趋势较低。它们显示出很高的可能影响传导系统,从而导致心律失常、传导阻滞和室性心动过速,可能导致猝死,三分之一的患者发生[3]。一项研究表明,位于室间隔区域的纤维瘤是一个重要的预后因素,因为它是心律失常的高趋势[7]。它可能阻塞流出或流入道,影响血流动力学,从而导致胸痛、呼吸短促甚至心力衰竭。许多研究强调了超声心动图的关键作用,因为它是非侵入性的,方便的,对分析小肿瘤和位于瓣膜上的肿瘤具有敏感性,显示肿瘤的大小,位置,心脏[8]的血流动力学和功能。因此,超声心动图在今天被认为是一种常规的做法。计算机断层扫描和MRI是二级检查,以确定位置和与周围结构的关系,因为它们是手术[9]必不可少的。心肌纤维瘤与横纹肌瘤[1]在MRI图像特征上有明显差异。 For fibroma, the characteristics include: 1) intramyocardial locations involving the ventricular septum or free wall; 2) well-defined borders with a thin rim of the myocardium; and 3) a heterogeneous appearance on T1- and T2-weighted TSE sequences with T1 iso-intensity, T2 slightly hypo-intensity and no signal change after fat suppression imaging. For rhabdomyoma, the characteristics include: 1) intramyocardial or intracavitary locations attached to the myocardium; 2) mildly hyperintense on T2-weighted TSE imaging; and 3) homogenous appearance on all sequences.