Association of Oscillatory Ventilation during Cardiopulmonary Test to Clinical and Functional Variables of Chronic Heart Failure Patients

Abstract Objective: The aim of this study is to characterize the presence of exercise oscillatory ventilation (EOV) and to relate it with other cardiopulmonary exercise test (CET) responses and clinical variables. Methods: Forty-six male patients (age: 53.1±13.6 years old; left ventricular ejection fraction [LVEF]: 30±8%) with heart failure were recruited to perform a maximal CET and to correlate the CET responses with clinical variables. The EOV was obtained according to Leite et al. criteria and VE/VCO2 > 34 and peak VO2 < 14 ml/kg/min were used to assess patients' severity. Results: The EOV was observed in 16 of 24 patients who performed the CET, as well as VE/VCO2 > 34 and peak VO2 < 14 ml/kg/min in 14 and 10 patients, respectively. There was no difference in clinical and CET variables of the patients who presented EOV in CET when compared to non-EOV patients. Also, there was no difference in CET and clinical variables when comparing patients who presented EOV and had a VE/VCO2 slope > 34 to patients who just had one of these responses either. Conclusion: The present study showed that there was an incidence of patients with EOV and lower peak VO2 and higher VE/VCO2 slope values, but they showed no difference on other prognostic variables. As well, there was no influence of the presence of EOV on other parameters of CET in this population, suggesting that this variable may be an independent marker of worst prognosis in HF patients.

研究目的：本研究旨在明确运动性周期性通气（exercise oscillatory ventilation, EOV）的发生情况，并分析其与其他心肺运动试验（cardiopulmonary exercise test, CET）指标及临床变量的相关性。
研究方法：本研究招募了46名男性心力衰竭患者（年龄：53.1±13.6岁；左心室射血分数[LVEF]：30±8%），要求所有受试者接受极量心肺运动试验（maximal CET），并分析试验指标与临床变量的相关性。运动性周期性通气的判定参照Leite等人提出的标准，同时采用VE/VCO2＞34及峰值摄氧量（peak VO2）＜14 ml/kg/min作为评估患者病情严重程度的指标。
研究结果：完成心肺运动试验的24例患者中，16例检出运动性周期性通气；另有14例患者VE/VCO2＞34，10例患者峰值摄氧量＜14 ml/kg/min。与未检出运动性周期性通气的患者相比，检出该现象的患者在临床及心肺运动试验相关变量上均无显著差异。此外，同时检出运动性周期性通气且VE/VCO2斜率（VE/VCO2 slope）＞34的患者，与仅具备其中一项指标的患者相比，其心肺运动试验指标及临床变量亦无显著差异。
研究结论：本研究显示，本研究人群中存在运动性周期性通气、峰值摄氧量降低及VE/VCO2斜率升高的患者占比可观，但这类患者在其他预后相关变量上并无差异。此外，运动性周期性通气的存在对该人群的其他心肺运动试验参数无显著影响，提示该指标或可作为心力衰竭患者不良预后的独立标志物。