性别和升主动脉瘤直径对主动脉重构的影响

摘要

Objective To evaluate the effect of size of ascending aortic aneurysm and sex on remodeling and me -chanical characteristics of aorta .Methods 67 patients with ascending aortic aneurysm undergoing selective surgery and 90 control patients with normal aortas undergoing coronary artery bypass grafting were selected .According to aneurysm di-ameter, 67 patients were further divided into 4 subgroups, <4 cm (n=11), 4-5 cm (n=9), 5-6 cm (n=31) and>6 cm (n=16).Aortic distensibility (Dist), wall stress (WS) and incremental elastic modulus (Einc) were measured in all patients .Results Mean end-systolic diameter was significantly shorter than end -diastolic diameter in the aneuris-mal and control groups and all 4 subgroups (P<0.05), which was more evident in men than in women (P<0.05).Aor-tic distensibility was reduced in both male and female groups (P<0.05).Wall stress increased with increaseing aortic di-ameter, comparing the 4 aneurysmal subgroups and the control group .Incremental elastic modulus was elevated in the an-eurismal group than in the control group ( P<0.05 ) , showing an increasing trend with increasing diameter of aneurysm (P<0.05).Conclusion There may be differences between male and female in the remodeling and biomechanical char-acteristics of the aorta , where aortic diameter and aortic wall stress were less in female .When aortic diameter is greater than 5 cm, remodeling occurs in a geometrical change in morphology .When aortic diameter is greater than 6 cm, aortic wall thickness decreases more evidently , giving rise to a rapid increase in the occurrence of acute vascular events , e.g. aortic dissection formation or rupture .%目的：探讨性别和升主动脉瘤直径对主动脉重构及其力学特性的影响。方法选取67例升主动脉瘤患者（病例组），并选取90例单纯行冠状动脉搭桥手术患者作为对照组，依据主动脉瘤直径大小分为4个亚组，直径小于4 cm（n＝11），直径4～5 cm（n＝9），直径～6 cm（n＝31）和直径＞6 cm（n＝16）。检测各组主动脉壁膨胀性、主动脉壁应力和增量弹性模量。结果病例组及其4个亚组和对照组的平均收缩期末的主动脉直径，与同组舒张期末同性别相比明显缩小（P＜0.05）。和对照组平均收缩期末及舒张期末主动脉直径比较，病例组男性患者比女性患者明显扩大（P＜0.05）。女性主动脉壁膨胀性比男性明显下降（P＜0.05）。病例组比对照组男、女性主动脉壁应力明显增加（P＜0.05），随着升主动脉瘤直径的增加，主动脉壁应力也逐渐增加，病例组4个亚组与对照组相比，差异有统计学意义（P＜0.05）。病例组增量弹性模量比对照组明显增加（P＜0.05），随着升主动脉瘤直径的增加，增量弹性模量明显增加（ P＜0.05）。结论升主动脉重构及其力学特性存在性别差异，与男性相比，女性有较小的主动脉直径和较低的应力。升主动脉瘤直径＞5 cm时，以几何学形态改变为主，血管呈扩张状态，管壁厚度变薄，＞6 cm时主动脉壁厚更加明显变薄，形成夹层或破裂的急性血管事件概率将快速上升。