Walsh R A
Am J Med. 1987 Jan 26;82(1B):34-40. doi: 10.1016/0002-9343(87)90269-5.
An understanding of the effects of aging upon the cardiovascular system assumes greater clinical importance as the population ages. Animal studies demonstrate prolonged tension development, impaired relaxation, and diminished response to receptor-mediated inotropic interventions in the cardiac muscle of senescent animals. Ventricular afterload is augmented at rest and increases during exercise through age-related alterations in peripheral arteries. Increased impedance to ejection may result in the modest concentric left ventricular hypertrophy seen in the elderly. Despite changes in cardiovascular function, resting and exercising cardiac outputs are well maintained in healthy elderly individuals who are free of occult coronary artery disease. The reduction in maximal oxygen consumption appears secondary to altered peripheral oxygen utilization rather than to cardiac causes.
随着人口老龄化，了解衰老对心血管系统的影响在临床上具有越来越重要的意义。动物研究表明，衰老动物的心肌存在张力发展延长、舒张受损以及对受体介导的变力干预反应减弱的情况。通过外周动脉与年龄相关的改变，心室后负荷在静息时增加，运动时进一步升高。射血阻抗增加可能导致老年人出现轻度向心性左心室肥厚。尽管心血管功能发生了变化，但没有隐匿性冠状动脉疾病的健康老年人在静息和运动时的心输出量能得到良好维持。最大氧耗量的降低似乎继发于外周氧利用的改变，而非心脏原因。
