Russell Stuart D, Saval Matthew A, Robbins Jennifer L, Ellestad Myrvin H, Gottlieb Stephen S, Handberg Eileen M, Zhou Yi, Chandler Bleakley
Department of Medicine, Johns Hopkins Hospital, Baltimore, MD 21287, USA.
Am Heart J. 2009 Oct;158(4 Suppl):S24-30. doi: 10.1016/j.ahj.2009.07.017.
The New York Heart Association (NYHA) functional class is a subjective estimate of a patient's functional ability based on symptoms that do not always correlate with the objective estimate of functional capacity, peak oxygen consumption (peak V(O2)). In addition, relationships between these 2 measurements have not been examined in the current medical era when patients are using beta-blockers, aldosterone antagonists, and cardiac resynchronization therapy (CRT). Using baseline data from the HF-ACTION (Heart Failure and A Controlled Trial Investigating Outcomes of Exercise TraiNing) study, we examined this relationship.
One thousand seven hundred fifty-eight patients underwent a symptom-limited metabolic stress test and stopped exercise due to dyspnea or fatigue. The relationship between NYHA functional class and peak V(O2) was examined. In addition, the effects of beta-blockers, aldosterone antagonists, and CRT therapy on these relationships were compared.
The NYHA II patients have a significantly higher peak Vo(2) (16.1 +/- 4.6 vs 13.0 +/- 4.2 mL/kg per minute), a lower ventilation (Ve)/V(CO2) slope (32.8 +/- 7.7 vs 36.8 +/- 10.4), and a longer duration of exercise (11.0 +/- 3.9 vs 8.0 +/- 3.4 minutes) than NYHA III/IV patients. Within each functional class, there was no difference in any of the exercise parameters between patients on or off of beta-blockers, aldosterone antagonists, or CRT therapy. Finally, with increasing age, a significant difference in peak Vo(2), Ve/V(CO2) slope, and exercise time was found.
For patients being treated with current medical therapy, there still is a difference in true functional capacity between NYHA functional class II and III/IV patients. However, within each NYHA functional class, the presence or absence or contemporary heart failure therapies does not alter exercise parameters.
纽约心脏协会（NYHA）心功能分级是基于症状对患者功能能力的主观评估，而这些症状并不总是与功能容量的客观评估——峰值耗氧量（峰值V（O2））相关。此外，在患者使用β受体阻滞剂、醛固酮拮抗剂和心脏再同步治疗（CRT）的当前医学时代，尚未对这两种测量之间的关系进行研究。利用心力衰竭与运动训练结局对照试验（HF-ACTION）研究的基线数据，我们对这种关系进行了研究。
1758例患者接受了症状限制的代谢应激试验，并因呼吸困难或疲劳而停止运动。研究了NYHA心功能分级与峰值V（O2）之间的关系。此外，还比较了β受体阻滞剂、醛固酮拮抗剂和CRT治疗对这些关系的影响。
与NYHA III/IV级患者相比，NYHA II级患者的峰值Vo（2）显著更高（16.1±4.6对13.0±4.2 ml/kg每分钟），通气（Ve）/V（CO2）斜率更低（32.8±7.7对36.8±10.4），运动持续时间更长（11. ……完整译文请参考：https://www.51test.net/show/11027774.html 。如需更完整准确的译文，可提供更多信息或参考专业医学文献翻译资料。
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