Sarma Satyam, Levine Benjamin D
Institute for Exercise and Environmental Medicine, Texas Health Prebysterian Hospital, Dallas, Texas; and Department of Internal Medicine, University of Texas Southwestern Medical Branch, Dallas, Texas
Institute for Exercise and Environmental Medicine, Texas Health Prebysterian Hospital, Dallas, Texas; and Department of Internal Medicine, University of Texas Southwestern Medical Branch, Dallas, Texas.
J Appl Physiol (1985). 2015 Sep 15;119(6):734-8. doi: 10.1152/japplphysiol.01127.2014. Epub 2015 Jun 5.
Patients with heart failure with preserved ejection fraction (HFpEF) have similar degrees of exercise intolerance and dyspnea as patients with heart failure with reduced EF (HFrEF). The underlying pathophysiology leading to impaired exertional ability in the HFpEF syndrome is not completely understood, and a growing body of evidence suggests "peripheral," i.e., noncardiac, factors may play an important role. Changes in skeletal muscle function (decreased muscle mass, capillary density, mitochondrial volume, and phosphorylative capacity) are common findings in HFrEF. While cardiac failure and decreased cardiac reserve account for a large proportion of the decline in oxygen consumption in HFrEF, impaired oxygen diffusion and decreased skeletal muscle oxidative capacity can also hinder aerobic performance, functional capacity and oxygen consumption (V̇o2) kinetics. The impact of skeletal muscle dysfunction and abnormal oxidative capacity may be even more pronounced in HFpEF, a disease predominantly affecting the elderly and women, two demographic groups with a high prevalence of sarcopenia. In this review, we 1) describe the basic concepts of skeletal muscle oxygen kinetics and 2) evaluate evidence suggesting limitations in aerobic performance and functional capacity in HFpEF subjects may, in part, be due to alterations in skeletal muscle oxygen delivery and utilization. Improving oxygen kinetics with specific training regimens may improve exercise efficiency and reduce the tremendous burden imposed by skeletal muscle upon the cardiovascular system.
射血分数保留的心力衰竭（HFpEF）患者与射血分数降低的心力衰竭（HFrEF）患者具有相似程度的运动不耐受和呼吸困难。导致HFpEF综合征运动能力受损的潜在病理生理学尚未完全了解，越来越多的证据表明“外周”，即非心脏因素可能起重要作用。骨骼肌功能的变化（肌肉质量、毛细血管密度、线粒体体积和磷酸化能力降低）是HFrEF的常见表现。虽然心力衰竭和心脏储备降低在HFrEF中占氧耗下降的很大比例，但氧扩散受损和骨骼肌氧化能力降低也会阻碍有氧运动能力、功能能力和氧耗（V̇o2）动力学。骨骼肌功能障碍和异常氧化能力的影响在HFpEF中可能更为明显，HFpEF是一种主要影响老年人和女性的疾病，这两个人口群体肌少症患病率很高。在本综述中，我们1）描述骨骼肌氧动力学的基本概念，2）评估证据表明HFpEF受试者有氧运动能力和功能能力的限制可能部分归因于骨骼肌氧输送和利用的改变。通过特定训练方案改善氧动力学可能会提高运动效率，并减轻骨骼肌对心血管系统造成的巨大负担。
