Robert H. Anderson, Sandra Webb, and Nigel A. Brown are at the Department of Pediatrics, National Heart & Lung Institute, Royal Brompton Hospital, London SW3 6LY, United Kingdom.; the MRC Experimental Embryology, St. George's Hospital Medical School, London, United Kingdom.; Teratology Unit, St. George's Hospital Medical School, London, United Kingdom.
Trends Cardiovasc Med. 1996 Jan;6(1):10-5. doi: 10.1016/1050-1738(95)00123-9.
A detailed knowledge of the precise morphology of the congenitally malformed heart has never been more important. In fields as diverse as clinical genetic counseling, epidemiology, surgery, and development biology, a proper description of morphology is essential to understand the cause and prevention of cardiac malformations. There has been a tendency in the past to categorize malformed hearts on the basis of putative developmental faults that are deduced from abnormal morphology, for example "endocardial cushion" or "looping" defects. We consider that this is potentially misleading. A better approach is exactly to determine cardiac structure so as to identify the "hallmark" (or "prototype") morphology of a given lesion. The hallmark will constitute those features, among all the changes in a malformed heart, that best define its fundamental character. As an example of the confusion produced by mechanistic extrapolation, consider the cleft in the anterior leaflet of an otherwise normal mitral valve, compared with the space between the leaflets bridging the ventricular septum in hearts with common atrioventricular junctions and deficient atrioventricular septation ("atrioventricular canal malformations"). It is probably correct to presume that both of these entities result from failure of fusion of the atrioventricular endocardial cushions. It is quite inappropriate, in contrast, to group these two lesions together morphologically, given the major anatomical differences seen in the formed hearts (Sigfússon et al. 1995). Therefore it is also important from the stance of developmental biology that the precise morphology of a genetically or chemically induced lesion be recognized if appropriate inferences are to be drawn for consideration of morphogenetic mechanisms and of comparable lesions in humans.
对先天性畸形心脏的精确形态的详细了解从未像现在这样重要。在临床遗传咨询、流行病学、外科学和发育生物学等不同领域，正确描述形态对于理解心脏畸形的原因和预防至关重要。过去，人们倾向于根据异常形态推断出的所谓发育缺陷来对畸形心脏进行分类，例如“心内膜垫”或“环”缺陷。我们认为这可能具有误导性。更好的方法是准确地确定心脏结构，以便识别给定病变的“特征”（或“原型”）形态。特征将构成畸形心脏中所有变化中最好地定义其基本特征的那些特征。作为机械推断产生混淆的一个例子，请考虑正常二尖瓣前叶的裂缝与心室间隔之间的空间相比，在具有共同房室结和房室间隔缺损（“房室管畸形”）的心脏中，间隔在瓣叶之间桥接。可能正确的假设是，这两个实体都源于房室心内膜垫融合失败。相比之下，鉴于形成的心脏中存在的主要解剖差异，将这两种病变在形态上归为一组是非常不合适的（Sigfússon 等人，1995 年）。因此，从发育生物学的角度来看，如果要对形态发生机制和人类中类似病变进行适当推断，识别遗传或化学诱导病变的精确形态也很重要。
