Hokken R B, Bartelings M M, Bogers A J, Gittenberger-de Groot A C
Department of Cardiopulmonary Surgery, University Hospital Dijkzigt, Rotterdam, The Netherlands.
J Thorac Cardiovasc Surg. 1997 Mar;113(3):453-61. doi: 10.1016/S0022-5223(97)70357-X.
Aortic root replacement with the pulmonary autograft warrants a thorough histologic comparison of the morphologic characteristics of the pulmonary and aortic roots. For this purpose nine normal heart specimens (7 neonatal and 2 adult hearts) were studied. Histologic study confirmed the collagenous anulus in both roots to be a complex circular-shaped structure, intricately interposed between the elastic lamellae of the arterial wall and the ventricular structures of the heart. In this sinus the elastic lamellae of the arterial wall continue along the luminal side with collagen being situated at the outside. At the interleaflet triangle this relation is reversed. Surprisingly, islet of elastic fibers were found in the otherwise completely collagenous interleaflet triangles. The amount of elastic lamella distal to the commissures was in both arteries higher than that in the middle of the sinuses, with a preponderance in the aorta as compared with the pulmonary trunk. The pulmonary root anulus proximally inserts into the relatively thin right ventricular myocardium, whereas the aortic root anulus inserts into the thick left ventricular myocardium and several fibrous structures. The pulmonary root is hardly supported by the right ventricular myocardium, whereas the aortic root is supported by its wedged position between the left and right atrioventricular anuli and the bulging thick left ventricular myocardium. When the pulmonary autograft is used for aortic root replacement it should be inserted as proximally as possible to get the support of the fibrous structures of the left ventricular outflow tract and the surrounding ventricular and atrial myocardium.
采用自体肺动脉瓣进行主动脉根部置换需要对肺动脉根部和主动脉根部的形态学特征进行全面的组织学比较。为此，研究了9个正常心脏标本（7个新生儿心脏和2个成人心脏）。组织学研究证实，两个根部的胶原环都是复杂的圆形结构，错综复杂地介于动脉壁的弹性膜和心脏的心室结构之间。在这个窦中，动脉壁的弹性膜沿着管腔侧延续，而胶原位于外侧。在瓣叶间三角区，这种关系则相反。令人惊讶的是，在原本完全由胶原组成的瓣叶间三角区发现了弹性纤维小岛。两个动脉中，连合远端的弹性膜数量均高于窦中部，与肺动脉干相比，主动脉中的弹性膜数量更多。肺动脉根部环近端插入相对较薄的右心室心肌，而主动脉根部环插入较厚的左心室心肌和几个纤维结构。肺动脉根部几乎没有得到右心室心肌的支撑，而主动脉根部则因其楔入左右房室环之间以及鼓起的厚左心室心肌之间的位置而得到支撑。当使用自体肺动脉瓣进行主动脉根部置换时，应尽可能近端插入，以获得左心室流出道的纤维结构以及周围心室和心房心肌的支撑。
