EXERCISE TRAINING/DIASTOLIC HEART FAILURE IN THE ELDERLY

舒张性心力衰竭占心力衰竭病例的50%以上 在65岁以上的人群中， 美国老年人的问题 我们目前的研究表明， 老年舒张性心力衰竭患者有剧烈运动 不容忍，这与运动训练改善。 然而，在这方面， 不到30%的改善归因于 心输出量 这表明，受损的潜在作用 通过损害肌肉灌注进行外周血管调节。 我们 初步数据表明，在老年舒张性心力衰竭患者中， 内皮依赖性血流介导的动脉扩张（FMAD）是 严重受损，与运动能力相关， 运动训练后增加。 本研究的主要目的 对60名老年人进行初步的横断面比较， 舒张性心力衰竭患者（症状性心力衰竭，正常 左室射血分数和无明显冠状动脉或瓣膜心脏 疾病或肺部疾病）与匹配的健康正常受试者 然后让病人进入一个随机对照的 有氧运动训练的盲法试验， 具体假设如下：1. 老年舒张性心力衰竭 与年龄和性别相比，患者的FMAD降低 匹配的健康正常受试者。 2. 运动不耐受 老年舒张性心力衰竭患者与降低 FMAD。 3. 老年心力衰竭患者的运动训练 改善FMAD和运动能力。 4. 改善 运动能力将与FMAD的改善相关。 一 第二个目的是检查FMAD和其他 心室-血管耦合的决定因素。 原则 测量包括肱动脉FMAD和颈动脉指数 高分辨率超声检测动脉僵硬度;脉搏波速度 通过眼压测量;最大和次最大氧耗量， 通过呼气分析确定无氧阈值， 通过数字超声心动图测量体积。 本研究将评估 内皮功能障碍对运动不耐受的影响 舒张性心力衰竭使用生理上合理的，广泛 适用的干预。

Diastolic heart failure accounts for over 50% of heart failure cases in the population greater than 65 and is an important health care problem for older Americans. Our current research shows that elderly patients with diastolic heart failure have severe exercise intolerance and that this improves with exercise training. However, less than 30% of the improvement is attributable to increased cardiac output. This suggests a potential role for impaired peripheral vasoregulation by compromising muscle perfusion. Our pilot data suggest that in elderly diastolic heart failure patients endothelial dependent flow mediated arterial dilation (FMAD) is substantially impaired, correlates with exercise capacity, and is increased after exercise training. The primary aims of this study are to perform an initial cross-sectional comparison of 60 elderly diastolic heart failure patients (symptomatic heart failure, a normal LV ejection fraction and no significant coronary or valvular heart disease or pulmonary disease) with matched healthy normal subjects and then to enter the patients into a randomized, controlled, single blinded trial of aerobic exercise training in order to test the following specific hypotheses: 1. Elderly diastolic heart failure patients have decreased FMAD compared to age and gender matched healthy normal subjects. 2. Exercise intolerance in elderly diastolic heart failure patients is associated with decreased FMAD. 3. Exercise training in elderly heart failure patients will improve FMAD and exercise capacity. 4. Improvements in exercise capacity will correlate with improvements in FMAD. A secondary aim is to examine relationship between FMAD and other determinants of ventricular-vascular coupling. Principle measurements include brachial artery FMAD and indexes of carotid artery stiffness by high resolution ultrasound; pulse wave velocity by tonometry; maximal and submaximal oxygen consumption and ventilatory anerobic threshold by expired gas analysis, and cardiac volumes by digital echocardiography. This study will assess the contribution of endothelial dysfunction to exercise intolerance in diastolic heart failure using a physiologically rational, widely applicable intervention.