PDF(Pubmed)
Abstract：
Adverse effects of large artery stiffening are well established in the systemic circulation; stiffening of the proximal pulmonary artery (PPA) and its sequelae are poorly understood. We combined in vivo (n = 6) with ex vivo data from cadavers (n = 8) and organ donors (n = 13), ages 18 to 89, to assess whether aging of the PPA associates with changes in distensibility, biaxial wall strain, wall thickness, vessel diameter, and wall composition. Aging exhibited significant negative associations with distensibility and cyclic biaxial strain of the PPA (p ≤ 0.05), with decreasing circumferential and axial strains of 20% and 7%, respectively, for every 10 years after 50. Distensibility associated directly with diffusion capacity of the lung (R2 = 0.71, p = 0.03). Axial strain associated with right ventricular ejection fraction (R2 = 0.76, p = 0.02). Aging positively associated with length of the PPA (p = 0.004) and increased luminal caliber (p = 0.05) but showed no significant association with mean wall thickness (1.19 mm, p = 0.61) and no significant differences in the proportions of mural elastin and collagen (p = 0.19) between younger (<50 years) and older (>50) ex vivo samples. We conclude that age-related stiffening of the PPA differs from that of the aorta; microstructural remodeling, rather than changes in overall geometry, may explain age-related stiffening.
摘要：
在体循环中已经很好地确定了大动脉硬化的不利影响；对近端肺动脉（PPA）的硬化及其后遗症知之甚少。我们将体内（n=6）与尸体（n=8）和器官供体（n=13）的离体数据相结合，年龄在18至89岁之间，以评估PPA的老化是否与扩张性的变化有关，双轴壁应变，壁厚,血管直径,墙的组成。老化与PPA的扩张性和周期性双轴应变表现出显著的负相关(p≤0.05)，随着周向和轴向应变的减少20%和7%，分别,50年后每10年。扩张性与肺的扩散能力直接相关(R2=0.71,p=0.03)。轴向应变与右心室射血分数相关(R2=0.76,p=0.02)。老化与PPA长度（p=0.004）和管腔口径增加（p=0.05）呈正相关，但与平均壁厚（1.19mm，p=0.61），并且在较年轻（<50岁）和较年长（>50）的离体样品之间，壁弹性蛋白和胶原蛋白的比例没有显着差异（p=0.19）。我们得出的结论是，与年龄相关的PPA硬化不同于主动脉；微结构重塑，而不是整体几何形状的变化，可以解释与年龄相关的僵硬。
