Gravanis M B
Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia.
Mod Pathol. 1989 Sep;2(5):495-505.
The problem of accelerated atherosclerosis in the allograft heart continues to adversely effect the long term survival of transplant patients. Most traditional risk factors influencing atherogenesis do not appear to play an important role in accelerated atherosclerosis. Additional causative factors proposed in recent years are not without controversy. An immune-mediated endothelial damage by cytotoxic B-cell antibodies as the initial injury in the induction of accelerated atherosclerosis has not been confirmed on morphologic grounds. This study is based on six cases (four autopsies and two explanted hearts) from transplant patients whose hearts were examined at different post-transplantation intervals (24 h to 14 mo). Our morphologic findings of a segmental coronary vasculitis involving primarily the outer two-thirds of the media and adventitia suggest that the early vascular manifestations may reflect tissue rejection similar to that seen in the myocardium. Furthermore, our findings from the medium size coronary arteries are suggestive of a cell-mediated immune injury probably directed against the smooth muscle cells of the media. Although the end result (occlusive coronary lesion) may reveal some morphologic similarities in both naturally occurring atherosclerosis and accelerated atherosclerosis, the pathogenetic mechanisms involved in these two conditions may differ.
同种异体移植心脏中动脉粥样硬化加速的问题持续对移植患者的长期存活产生不利影响。大多数影响动脉粥样硬化形成的传统危险因素似乎在加速动脉粥样硬化过程中并不起重要作用。近年来提出的其他致病因素也并非没有争议。作为加速动脉粥样硬化诱导初始损伤的细胞毒性B细胞抗体介导的免疫性内皮损伤，在形态学依据上尚未得到证实。本研究基于6例移植患者的病例（4例尸检和2例切除心脏），这些患者的心脏在移植后的不同时间间隔（24小时至14个月）进行了检查。我们的形态学发现显示，节段性冠状动脉血管炎主要累及中膜和外膜的外三分之二，提示早期血管表现可能反映了与心肌中所见类似的组织排斥反应。此外，我们从中等大小冠状动脉得出的发现提示可能存在针对中膜平滑肌细胞的细胞介导免疫损伤。尽管最终结果（闭塞性冠状动脉病变）在自然发生的动脉粥样硬化和加速动脉粥样硬化中可能显示出一些形态学相似性，但这两种情况所涉及的发病机制可能不同。
