Bhatt Digant V, Kocheril Abraham G
From the Department of Cardiology, Dartmouth Hitchcock Medical Center, Lebanon, New Hampshire, and the University of Illinois College of Medicine at Urbana-Champaign.
South Med J. 2014 Mar;107(3):144-9. doi: 10.1097/SMJ.0000000000000066.
Gas exchange measurements obtained during submaximal exercise have been shown to provide prognostic and diagnostic information in patients with heart failure (HF) and to differentiate heart versus lung limitations in patients with unexplained dyspnea. The aim of our study was to assess the clinical utility of submaximal cardiopulmonary exercise testing using the Shape-HF equipment in identifying the cause of unexplained dyspnea.
A total of 65 patients underwent Shape-HF tests from September 2010 to June 2011 for unexplained dyspnea at our center.
Of 65 patients, 39 were men and 26 were women. In this study, 23 patients had preexisting asthma or chronic obstructive pulmonary disease (COPD); 19 patients had a pacemaker (8), an implantable cardioverter defibrillator (2), or a cardiac resynchronization therapy defibrillator (CRT-D) (9). The study revealed that submaximal cardiopulmonary exercise testing provided supportive clinical data for deconditioning, pulmonary limitations (eg, COPD, interstitial lung disease, sleep apnea), pulmonary hypertension, and chronotropic incompetence in 21.5%, 23.1%, 13.8%, and 6.2% of patients, respectively. Pulmonary hypertension was confirmed in 55% of patients by echocardiography and lung problems were confirmed in 40% of patients by pulmonary function test and sleep study. Of nine patients with an implanted CRT-D, optimization of atrioventricular and interventricular programming was performed in seven (78%) using gas exchange monitoring while performing a steady state, low-level treadmill walk.
Submaximal cardiopulmonary exercise testing has strongly suggested the diagnosis of COPD, interstitial lung disease, pulmonary hypertension, and deconditioning and has led to appropriate testing. Based on prior studies, we also used Shape-HF for its approved purpose of optimizing CRT-D programming in patients with HF, leading to clinical improvement.
已证明在次最大运动期间获得的气体交换测量结果可为心力衰竭（HF）患者提供预后和诊断信息，并区分不明原因呼吸困难患者的心脏与肺部限制因素。我们研究的目的是评估使用Shape-HF设备进行次最大心肺运动测试在确定不明原因呼吸困难病因方面的临床效用。
2010年9月至2011年6月，共有65例因不明原因呼吸困难在我们中心接受Shape-HF测试。
65例患者中，男性39例，女性26例。本研究中，23例患者既往有哮喘或慢性阻塞性肺疾病（COPD）；19例患者有起搏器（8例）、植入式心脏复律除颤器（2例）或心脏再同步化治疗除颤器（CRT-D）（9例）。研究显示，次最大心肺运动测试分别为21.5%、23.1%、13.8%和6.2%的患者提供了关于身体机能下降、肺部限制因素（如COPD、间质性肺疾病、睡眠呼吸暂停）、肺动脉高压和变时性功能不全的支持性临床数据。55%的患者经超声心动图确诊为肺动脉高压，40%的患者经肺功能测试和睡眠研究确诊为肺部问题。在9例植入CRT-D的患者中，7例（78%）在进行稳态、低强度跑步机步行时使用气体交换监测对房室和室内程控进行了优化。
次最大心肺运动测试有力地提示了COPD、间质性肺疾病、肺动脉高压和身体机能下降的诊断，并促使进行了适当的检查。基于先前的研究，我们还将Shape-HF用于其已获批用途，即优化HF患者的CRT-D程控，从而实现临床改善。
