The Influence of Heart Failure Self-Care Behavior on Cardiac Performance

描述（由申请人提供）：心力衰竭（HF）是一种影响超过500万美国人的综合征，与残疾、发病率增加和生活质量下降有关。自我护理可能是控制心衰引起的体液潴留和内分泌反应的一种方法，这些反应会损害心脏功能并导致患者预后不良。虽然自我保健被假设会影响心脏功能，但这一说法的科学基础尚未建立。我们需要进一步的证据来证明心衰患者的日常自我护理实践可以影响心脏功能，从而使患者认识到他们在保持最佳心脏功能、提高健康质量和寿命方面所起的重要作用。我们打算使用生物阻抗心动图技术和激素测量，以及头部向下倾斜的策略程序来被动和非侵入性地挑战心脏的性能，以深入了解这种关系。提出了一项横断面研究，以检验使用主观和客观测量方法测量的HF自我保健与15分钟头向下倾斜姿势挑战时心脏性能的客观测量之间的关系。本研究的具体目的是：1)描述HF自我保健与基线心脏表现之间的关系，通过测量A)自我保健与心力衰竭自我保健指数、医学结局研究特定依从性量表和24小时尿钠水平来评估对低钠饮食的依从性；B)心脏表现与血钠肽水平（作为心房扩张的指标）和心脏血流动力学生物阻抗心电图（包括胸液容量指数）。脑卒中容量指数和加速度指数，以及2)描述了在15分钟、15¿头向下倾斜位置挑战下HF自我保健与心脏动态表现之间的关系。心衰自我保健的测量将与身体定位时心脏功能测量的相对变化进行比较。本研究探讨心力衰竭患者的自我照顾行为，以及他们在休息和压力下的心脏功能。这项研究将有助于确定心力衰竭患者的日常自我护理行为是否会影响心脏功能。

DESCRIPTION (provided by applicant): Heart failure (HF), a syndrome that affects more than five million Americans, is associated with disability, increased morbidity, and decreased quality-of-life. Self-care may be one way of controlling fluid retention and endocrine responses to HF that impair cardiac performance and lead to poor patient outcomes. Although self-care is hypothesized to influence cardiac performance, the scientific basis of this claim has not yet been established. We need further evidence that HF patient's day-to-day self-care practices can influence cardiac performance in order to impress on patients the important role that they play in maintaining optimal cardiac performance and in increasing the quality and years of their health. We intend to use bioimpedance cardiography technology and hormone measurement, along with a strategic procedure of head-down tilt to passively and non-invasively challenge the heart's performance to gain insight into this relationship. A cross-sectional study is proposed to examine the relationship between HF self-care measured using subjective and objective measures and the objective measurement of cardiac performance in response to fifteen minutes of a 15¿ head-down tilt positional challenge. The specific aims of this study are to: 1) describe the relationship between HF self-care and baseline cardiac performance, by measuring A) self-care with the Self-Care of Heart Failure Index, the Medical Outcomes Study Specific Adherence Scale, and 24-hour urine sodium levels to assess adherence to a low sodium diet, and B) cardiac performance with blood levels of atrial natriuretic peptide, as an index of atrial distension, and cardiac hemodynamics with bioimpedence cardiography, including thoracic fluid volume index, stroke volume index, and acceleration index, and 2) describe the relationship between HF self-care and dynamic cardiac performance in response to a fifteen minute, 15¿ head-down tilt positional challenge. Measures of HF self-care will be compared to the relative change in measures of cardiac performance in response to body positioning. This research study examines the self-care behaviors of persons with heart failure and how their heart functions at rest and when stressed. This study will help determine if the day-to-day self-care behaviors of heart failure patients can influence how the heart functions.