Luminal narrowing of coronary capillaries in human hypertrophic hearts: an ultrastructural morphometrical study using endomyocardial biopsy specimens
Luminal narrowing of coronary capillaries in human hypertrophic hearts: an ultrastructural morphometrical study using endomyocardial biopsy specimens
复制标题
人类肥厚心脏冠状毛细血管管腔变窄：使用心内膜心肌活检标本的超微结构形态测量研究
作者：
G. Takemura;Y. Takatsu;H. Fujiwara
背景 在患有病理状况的心脏中，特别是在肥厚的心脏中，即使存在正常的心外膜冠状动脉，也表明存在微循环异常。然而，这些心脏中冠状毛细血管的形态尚未得到很好的研究。方法对 30 例患者的 47 例心内膜心肌活检标本的毛细血管进行超微结构形态测定。患者 6 名患者患有肥厚型心肌病并伴有扩张型心肌病样特征（DCM 样 HCM），6 名患者患有 HCM，6 名患者患有 DCM，5 名患者患有心肌后炎，7 名患者为正常受试者。结果各组毛细血管短轴径相似。 DCM样HCM组毛细血管有31%、HCM组16%、DCM组13%、心肌炎后组11%和正常受试者2%，发现管腔狭窄超过90%的异常狭窄。 DCM 样 HCM 中管腔平均 (SD) 狭窄最严重 (78(8)%)，HCM (67(9)%)、DCM (66(8)%) 和心肌后炎 (68(4)%) 中管腔狭窄比正常受试者 (56(8)%) 更严重。各组之间毛细血管的平均横截面积相似；然而，DCM样HCM的内皮细胞面积（24.2 （8.2） μm2）显着（p< 0.05）大于正常受试者（14.7 （1.8） μm2），表明毛细血管变窄是由于毛细血管内皮细胞体积增加所致。狭窄毛细血管内皮细胞的细胞质全部或部分出现严重水肿改变，但细胞质细胞器和细胞核完整。结论 冠状毛细血管狭窄可能在肥厚心脏的微循环异常中具有病理生理学意义，特别是在 DCM 样 HCM 患者中。
Background Abnormal microcirculation has been suggested in hearts with pathological conditions, particularly in hypertrophic hearts, even in the presence of normal epicardial coronary arteries. However, the morphology of coronary capillaries has not been well investigated in those hearts. Methods Ultrastructural morphometry of the capillaries in 47 endomyocardial biopsy specimens taken from 30 patients was performed. Patients Six patients had hypertrophic cardiomyopathy with dilated cardiomyopathy-like features (DCM-like HCM), six had HCM, six had DCM, five had postmyocarditis, and seven were normal subjects. Results The short axial diameters of capillaries were similar among the groups. Abnormal stenosis of more than 90% luminal narrowing was found in 31% of capillaries of the DCM-like HCM group, 16% of the HCM group, 13% of the DCM group, 11% of the postmyocarditis group, and 2% of the normal subjects. Mean (SD) stenosis of the lumen was most severe in DCM-like HCM (78(8)%), and more severe in HCM (67(9)%), DCM (66(8)%), and postmyocarditis (68(4)%) than normal subjects (56(8)%). The mean cross sectional areas of capillaries were similar among the groups; however, the endothelial cellular area was significantly (p < 0.05) greater in DCM-like HCM (24.2 (8.2) μm2) than in normal subjects (14.7 (1.8) μm2), indicating that capillary narrowing was due to the increased volume of capillary endothelial cells. The endothelial cells of the stenosed capillaries showed severely oedematous changes of the cytoplasm wholely or partially, but the cytoplasmic organelles and nuclei appeared intact. Conclusion Narrowing of the coronary capillaries may be of pathophysiological significance in microcirculatory abnormality in hypertrophic hearts, particularly in patients with DCM-like HCM.