Introduction

Diabetes Mellitus (DM) has been known to be a risk factor for the development of more severe form of saphenous vein graft disease after coronary artery bypass grafting (CABG). We aimed to evaluate the impact of type II-DM on histopathological features of great saphenous vein grafts of patients undergoing CABG.

Patients and methods

Forty consecutive patients undergoing elective CABG were enrolled into the study. Patients were grouped into two; Diabetic group (n = 20); includes patients with preoperative diagnosis of type II-DM and Nondiabetic group (n = 20): those without type II-DM. In all patients, a short segment of the great saphenous vein graft at the level of medial malleolus was taken for light microscopy and transmission electron microscopy (TEM) evaluation. Moreover, immunoexpressions of Caveolin-1, Vascular cell adhesion protein 1 (VCAM-1) and endothelial nitric oxide synthase (eNOS) were studied.

Results

There were no differences in the demographics of patients between two groups. The magnitude of intimal fibrosis in diabetic group was slightly higher than in nondiabetics (1.95 ± 0.99 versus 1.3 ± 0.8, P = .04). In TEM, vacuolization in endothelial cells, substance accumulation along with coarse collagen fibers and cytoplasmic degeneration with vacuolization in muscle cells were detected in diabetic group. While there were no differences in Caveolin-1 and VCAM-1 immunostaining, the intensity of positive eNOS immunostaining was significantly higher in endothelium (2.10 ± 0.64 versus 1.55 ± 0.68, P = .01) and tunica media 1.75 ± 0.63 versus 1.2 ± 0.52, P = .007) in nondiabetic group, respectively) compared with diabetic group.

Conclusion

Type II DM might be a reason for decreased expression of eNOS and increased intimal fibrosis, vacuolization of endothelial and smooth muscle cells in saphenous vein grafts. The clinical implications of these alterations on the graft patency need to be evaluated.

中文翻译：

---

冠状动脉旁路移植术II型糖尿病患者大隐静脉移植的组织病理学评价

介绍

众所周知，糖尿病 (DM) 是冠状动脉旁路移植术 (CABG) 后发生更严重的隐静脉移植疾病的危险因素。我们旨在评估 II-DM 对 CABG 患者大隐静脉移植物组织病理学特征的影响。

患者和方法

接受选择性 CABG 的连续 40 名患者被纳入研究。患者分为两组；糖尿病组（n = 20）；包括术前诊断为 II-DM 的患者和非糖尿病组（n = 20）：没有 II-DM 的患者。在所有患者中，取一小段内踝水平的大隐静脉移植物进行光学显微镜和透射电子显微镜 (TEM) 评估。此外，研究了 Caveolin-1、血管细胞粘附蛋白 1 (VCAM-1) 和内皮一氧化氮合酶 (eNOS) 的免疫表达。

结果

两组患者的人口统计学无差异。糖尿病组内膜纤维化的程度略高于非糖尿病组（1.95 ± 0.99 vs 1.3 ± 0.8，P = .04）。透射电镜观察到糖尿病组内皮细胞有空泡化，随着粗胶原纤维物质的积累，细胞质变性伴肌细胞空泡化。虽然 Caveolin-1 和 VCAM-1 免疫染色没有差异，但内皮（2.10 ± 0.64 对 1.55 ± 0.68，P = .01）和中膜中eNOS 免疫染色阳性的强度显着更高，1.75 ± 0.63 对 1.2 ± 0.52 , P = .007) 在非糖尿病组中，分别) 与糖尿病组相比。

结论

II 型 DM 可能是 eNOS 表达降低和内膜纤维化增加、内皮细胞和平滑肌细胞空泡化在大隐静脉移植物中的一个原因。需要评估这些改变对移植物通畅性的临床意义。