Pica Silvia, Ghio Stefano, Raineri Claudia, Scelsi Laura, Turco Annalisa, Visconti Luigi Oltrona
G Ital Cardiol (Rome). 2014 Dec;15(12):717-9. doi: 10.1714/1718.18778.
Isolated left ventricular (LV) apical hypoplasia is a rare anomaly characterized by a dysfunctioning, spherical left ventricle and elongated right ventricle wrapping around the deficient LV apex. The etiology is unknown; it is presumed to be a rare congenital developmental defect during partitioning of the ventricles, caused by an in-utero infection. We describe for the first time a case of isolated LV apical hypoplasia associated with lamin A/C gene mutation. Echocardiography showed a mildly dilated left ventricle with spherical configuration and impaired systolic function, and an elongated right ventricle wrapping around the deficient LV apex. Magnetic resonance imaging also identified fatty replacement of the LV apical myocardium. Late gadolinium enhancement imaging showed mid-wall fibrosis in the interventricular septum. Family screening by ECG and echocardiography failed to identify heart disease in the patient's family; however, the proband's father and daughter were found to carry the same mutation. This case report highlights the difficulties of a correct interpretation of genetic mutations in a single patient with cardiomyopathy. Indeed, the causative role of a mutation needs to be confirmed by co-segregation analysis. Although the etiology of LV apical hypoplasia remains unknown, the first hypothesis is an acquired process interfering with the early development of the heart, the new one is a genetic defect.
孤立性左心室心尖发育不全是一种罕见的异常情况，其特征为功能失调的球形左心室以及围绕发育不全的左心室心尖延伸的右心室。病因不明；据推测是心室分隔期间一种罕见的先天性发育缺陷，由子宫内感染引起。我们首次描述了一例与核纤层蛋白A/C基因突变相关的孤立性左心室心尖发育不全病例。超声心动图显示左心室轻度扩张，呈球形结构，收缩功能受损，右心室延伸并围绕发育不全的左心室心尖。磁共振成像也显示左心室心尖心肌有脂肪替代。延迟钆增强成像显示室间隔中层纤维化。通过心电图和超声心动图对患者家族进行筛查，未发现该患者家族中有心脏病；然而，先证者的父亲和女儿被发现携带相同的突变。本病例报告强调了对单一心肌病患者基因突变进行正确解读的困难。确实，突变的致病作用需要通过共分离分析来证实。尽管左心室心尖发育不全的病因仍然不明，但第一种假说是一个干扰心脏早期发育的后天过程，新的假说则是一种基因缺陷。
