Arm Exercise versus Other Stress Test Modalities for Clinical Outcome Prediction

描述（由申请人提供）： 跑步机运动能力和腿部运动的血流动力学、症状和心电图（ECG）反应是全因死亡率和其他重要健康结局指标的有力预测因素，但对于因下肢残疾（如截肢、膝关节或其他关节病、肌病、跛行、脊髓或战斗损伤）而接受药物负荷试验的患者，这些信息均不可用。该项目的主要假设是，手臂测力计运动心电图负荷试验的复合结果，与选择性心肌灌注成像（MPI）在一个子集的患者，如那些高度异常的静息心电图或钝血流动力学反应，提供预后，临床和诊断信息相当于非选择性药理学MPI的一小部分，成本，时间消耗，辐射暴露，以及不能进行充分下肢运动的患者的机构设备和人员资源要求。为了研究这一假设，我们提出了以下具体目标：目的1目的1是在计算机化研究数据库中汇编关于人口统计学、基线临床特征、药物、应激测试和对应激的MPI反应以及随后的临床结果的数据，该数据库从接受360臂测力计的约5800名独特退伍军人的电子记录中获得，在1997年到2002年之间，在圣路易斯退伍军人管理医疗中心对患者进行了超过2000次双嘧达莫和3400次跑步机压力测试。 目的#2是通过单变量和多变量考克斯回归分析、Kaplan-Meier曲线和Wald G2模型来确定，在调整人口统计学、临床、心电图和运动负荷试验后，运动能力、血流动力学、症状、ECG和对臂功计、潘生丁和平板运动负荷试验的MPI反应独立预测生存率或全因死亡率、随后的心肌梗死（MI）或冠状动脉血运重建术（单独和组合）。和药物变量，随访至死亡终点或2009年12月31日。 目的#3是使用受试者工作特征（ROC）曲线分析，比较独立预测臂功率计ECG负荷试验变量模型与潘生丁MPI、平板心电图、臂功率计和平板心电图加MPI结果的预后价值，以预测临床结局。 目标2：开发一个简单的评分系统，类似于杜克跑步机评分，从独立预测的臂功计ECG负荷试验变量中最好地预测死亡和MI。 目标#3目标#1是对上述数据库中基线ECG高度异常、对应激的血流动力学反应迟钝、应激ECG异常或运动能力低的患者亚组进行分层，假设MPI信息可能对结局的增量预测最有益。 目的2是研究MPI在这些亚组中的独立增量预后价值，并使用考克斯回归和G2分析比较MPI在不同退伍军人亚组中预测预后的增量价值。 公共卫生相关性： 2007年，大约有132，000名退伍军人在退伍军人管理局（VA）医院接受了心脏成像压力测试，每年有近900万美国人在美国进行此类研究，费用超过100亿美元。由于先前的战斗损伤，截肢，腿部或足部关节，脊髓，循环和其他下肢残疾，20-40%的此类患者进行了药理学评估，而不是腿部运动负荷试验，排除了获得强大的预后数据，可从运动试验预测生存和其他健康结果的措施。为了解决这一不足，在本项目中，我们建议继续我们以前发表的调查手臂运动作为替代药物或跑步机运动测试的退伍军人下肢残疾。

DESCRIPTION (provided by applicant): Treadmill exercise capacity and hemodynamic, symptomatic, and electrocardiographic (ECG) responses to leg exercise are powerful predictors of all-cause mortality and other important measures of health outcome but none of this information is available for patients who undergo pharmacologic stress tests because of lower extremity disabilities such as amputations, knee or other arthropathies, myopathies, claudication, spinal cord, or combat injuries. The major hypothesis of this project is that composite findings of arm ergometer exercise ECG stress testing, with selective myocardial perfusion imaging (MPI) in a subset of patients such as those with highly abnormal resting ECGs or blunted hemodynamic responses, provides prognostic, clinical, and diagnostic information equivalent to non-selective pharmacologic MPI at a fraction of the cost, time expenditure, radiation exposure, and institutional equipment and personnel resource requirements in patients who cannot perform adequate lower extremity exercise. To investigate this hypothesis, we propose the following specific aims and objectives: Aim # 1 Objective # 1 is to compile data on demographics, baseline clinical characteristics, medications, stress test and MPI responses to stress, and subsequent clinical outcome in a computerized research database obtained from electronic records of approximately 5800 unique veterans who underwent 360 arm ergometer, over 2000 dipyridamole, and 3400 treadmill stress tests performed on patients at the St. Louis Veterans Administration Medical Center between 1997 and 2002. Objective # 2 is to determine by univariate and multivariate Cox regression analyses, Kaplan-Meier curves, and Wald G2 models, which exercise capacity, hemodynamic, symptomatic, ECG and MPI responses to arm ergometer, dipyridamole and treadmill stress tests independently predict survival or all-cause mortality, subsequent myocardial infarction (MI), or coronary revascularization alone and in combination, after adjustment for demographic, clinical, and medication variables, during follow-up to an endpoint of death or 12/31/2009. Objective # 3 is to compare the prognostic value of a model of independently predictive arm ergometer ECG stress test variables with dipyridamole MPI, treadmill ECG, arm ergometer and treadmill ECG plus MPI results, using receiver operator characteristic (ROC) curve analyses, for prediction of clinical outcome. Aim # 2 The goal is to develop a simple scoring system, analogous to the Duke Treadmill Score, to best prognosticate death and MI from independently predictive arm ergometer ECG stress test variables. Aim # 3 Objective # 1 is to stratify subgroups of patients in the above data base with a highly abnormal baseline ECG, blunted hemodynamic responses to stress, an abnormal stress ECG or low exercise capacity, for whom it is hypothesized that MPI information might be most beneficial for incremental prognostication of outcome. Objective # 2 is to investigate the independent incremental prognostic value of MPI in these subgroups and compare the incremental value of MPI for prediction of outcome in the various subgroups of veterans using Cox regression and G2 analyses. PUBLIC HEALTH RELEVANCE: Approximately 132,000 veterans underwent cardiac imaging stress tests in Veterans Administration (VA) hospitals in 2007 and nearly 9 million Americans a year perform such studies in the United States as a whole at a cost of more than 10 billion dollars. Because of previous combat injuries, amputations, leg or foot joint, spinal cord, circulatory and other lower extremity disabilities, 20-40% of such patients are evaluated with pharmacologic rather than leg exercise stress tests, precluding access to the powerful prognostic data available from exercise tests for prediction of survival and other health outcome measures. To address this deficiency, in the present project we propose to continue our previous published investigations of arm exercise as an alternative to pharmacologic or treadmill exercise testing in veterans with lower extremity disabilities.