Chaumont Martin, Forton Kevin, Gillet Alexis, Tcheutchoua Nzokou Daryl, Lamotte Michel
Department of Cardiology, Erasme Hospital, 1070 Brussels, Belgium.
Healthcare (Basel). 2023 Apr 30;11(9):1292. doi: 10.3390/healthcare11091292.
Cardiopulmonary exercise testing (CPET) was limited to peak oxygen consumption analysis (VOpeak), and now the ventilation/carbon dioxide production (VE/VCO) slope is recognized as having independent prognostic value. Unlike VOpeak, the VE/VCO slope does not require maximal effort, making it more feasible. There is no consensus on how to measure the VE/VCO slope; therefore, we assessed whether different methods affect its value. This is a retrospective study assessing sociodemographic data, left ventricular ejection fraction, CPET parameters, and indications of patients referred for CPET. The VE/VCO slope was measured to the first ventilatory threshold (VT1-slope), secondary threshold (VT2-slope), and included all test data (full-slope). Of the 697 CPETs analyzed, 308 reached VT2. All VE/VCO slopes increased with age, regardless of test indications. In patients not reaching VT2, the VT1-slope was 32 vs. 36 ( < 0.001) for the full-slope; in those surpassing VT2, the VT1-slope was 29 vs. 33 ( < 0.001) for the VT2-slope and 37 (all < 0.001) for the full-slope. The mean difference between the submaximal and full-slopes was ±4 units, sufficient to reclassify patients from low to high risk for heart failure or pulmonary hypertension. We conclude that the method used for determining the VE/VCO slope greatly influences the result, the significant variations limiting its prognostic value. The calculation method must be standardized to improve its prognostic value.
心肺运动试验（CPET）过去仅限于峰值耗氧量分析（VOpeak），而现在通气/二氧化碳产生量（VE/VCO）斜率被认为具有独立的预后价值。与VOpeak不同，VE/VCO斜率不需要竭尽全力，使其更具可行性。关于如何测量VE/VCO斜率尚无共识；因此，我们评估了不同方法是否会影响其数值。这是一项回顾性研究，评估了社会人口统计学数据、左心室射血分数、CPET参数以及接受CPET检查患者的指征。测量了到达第一通气阈值（VT1斜率）、第二阈值（VT2斜率）时的VE/VCO斜率，并纳入了所有测试数据（全程斜率）。在分析的697例CPET中，308例达到了VT2。无论测试指征如何，所有VE/VCO斜率均随年龄增加。在未达到VT2的患者中，VT1斜率对于全程斜率为32比36（<0.001）；在超过VT2的患者中，VT1斜率对于VT2斜率为29比33（<0.001），对于全程斜率为37（均<0.001）。次最大斜率与全程斜率之间的平均差值为±4个单位，足以将患者从心力衰竭或肺动脉高压的低风险重新分类为高风险。我们得出结论，用于确定VE/VCO斜率的方法对结果有很大影响，显著差异限制了其预后价值。必须对计算方法进行标准化，以提高其预后价值。
