REGULATION OF LEFT VENTRICULAR VOLUMES AT REST AND DURING STRESS

静息时和应激时左心室容积的调节

• 批准号: 3802234
• 负责人: E LAKATTA
• 金额: --
• 依托单位: NATIONAL INSTITUTE ON AGING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3802234
• 关键词: aging; exercise; heart circulation; heart contraction; heart imaging /visualization /scanning; heart pharmacology; heart ventricle; human middle age (35-64); human old age (65+); intracardiac volume; male; propranolol; young adult human (21-34)

To determine the effect of age on exercise left ventricular volumes, independent of physical fitness level (F), we gated cardiac blood pool scans during graded maximal upright cycle exercise in 95 healthy men ages 23-86 years were analyzed. In the overall group left ventricular end diastolic volume index (EDVI) and end systolic volume index (ESVI) increased with age (r=0.37, p< .01 and r=0.46, p<.001 respectively) while left ventricular ejection fraction (LVEF) declined with age, r= -0.46, p<.001 and stroke volume index (SVI) was unrelated to age. In a subset of 49 men of homogenous fitness (maximal workload 125-150 watts), EDVI and ESVI increased and LVEF decreased with age as in the overall sample bur SVI now increased with age (r = 0.39, p < .01) due to an accentuated increased in EDVI (r = 0.51, p < .001). We tested whether acute beta-adrenergic blockade with propranolol altered the hemodynamic response to exercise seen with normative aging. In 85 healthy BLSA men not give propranolol, left ventricular EDVI increased with age (r=-0.41, p< .001), LVEF, heart rate (HR) and cardiac index (CI) declined with age (r=-0.45, p<.001, r=-0.78, p<.001, and r=-0.33, p<.01) respectively and SVI was not age related. In 25 men ages 28-72 years given intravenous propranolol, EDVI declined with age (r=-0.20) causing an age-associated decline in SVI (r=0.48, p<0.05) not present in the unblocked men. The decline in heart with age in propranolol-treated men was blunted (0.46 beats/min/yr) compared to controls (1.09 beats/min/yr). The primary reason for the slope shifts in the age regressions in the presence of propranolol was a large increase in EDVI and SVI and a large decrease in HR in younger men. Thus, while the age-associated decline in maximal EF is unaffected, acute beta blockade reverses the age-associated ventricular dilatation during upright cycle exercise and blunts the decline in maximal HR. The net effect is an accentuated decline of maximal CI with age.

为了确定年龄对运动左心室容积的影响， 独立于身体健康水平（F），我们门控心脏血池 对95名健康男性进行了分级最大垂直周期运动扫描 23-86岁。 在整个组中，左心室末端 舒张末期容积指数（EDVI）和收缩末期容积指数（ESVI） 随着年龄的增长而增加（分别为r=0.37，p<0.01和r=0.46，p<0.001）， 左室射血分数（LVEF）随年龄增长而下降，r=-0.46， P<0.001，每搏输出量指数（SVI）与年龄无关。 的子集中 49名同质健身的男性（最大工作量125-150瓦），EDVI和 与总体样本一样，ESVI随着年龄的增长而增加，LVEF随着年龄的增长而降低，但SVI 现在随着年龄的增长而增加（r = 0.39，p < .01），这是由于 EDVI的相关系数r = 0.51，p <0.001。 我们测试了急性β-肾上腺素能 用心得安阻断改变了对运动的血流动力学反应， 正常老化。 在85名健康的BLSA男性中，未给予普萘洛尔，左 心室EDVI随年龄增长而增加（r=-0.41，p <0.001），LVEF、心率 (HR)心脏指数（CI）随年龄增长而下降（r=-0.45，p = 0.001，r=-0.78，p = 0.001）， P<0.001和r=-0.33，P <0.01），SVI与年龄无关。 在 25名年龄在28-72岁的男性静脉注射普萘洛尔后，EDVI下降， 年龄（r=-0.20）导致SVI年龄相关性下降（r=0.48，p<0.05）， 存在于无障碍人群中。 随着年龄的增长， 普萘洛尔治疗的男性与对照组相比， 对照组（1.09次/分/年）。 斜率变化的主要原因是 普萘洛尔存在下的年龄回归是大幅增加 EDVI和SVI以及年轻男性的HR大幅下降。 因此， 年龄相关的最大EF下降不受影响，急性β受体阻滞剂 逆转直立周期中与年龄相关的心室扩张 运动并减缓最大心率的下降。净效应是 随着年龄的增长，最大CI的下降加剧。