Office of Human Research, Memorial Cardiac and Vascular Institute, Memorial Healthcare System, Hollywood, FL, USA.
Baylor College of Medicine, Texas Children's Hospital Austin Specialty Care, Austin, TX, USA.
Cardiol Young. 2021 Jan;31(1):91-96. doi: 10.1017/S104795112000339X. Epub 2020 Oct 19.
Peak respiratory exchange ratio is an objective marker of patient effort during cardiopulmonary exercise testing. We evaluated exercise variables in 175 adult congenital heart disease patients and the impact of respiratory exchange ratio on the prognostic value of exercise variables for short-term cardiac-related events. Of 175 patients, 110 completed the exercise test with a peak respiratory exchange ratio of ≥1.10 and the remaining 65 had a peak respiratory exchange ratio of <1.10. Peak oxygen consumption, the percentage of oxygen consumption at the ventilatory threshold, peak heart rate, percentage predicted peak heart rate, double product, oxygen uptake efficiency slope, and the number of patients with exercise oscillatory ventilation were reduced significantly in patients with a respiratory exchange ratio of <1.10 compared to those with a respiratory exchange ratio of ≥1.10. After a median follow-up of 21 months, total cardiac-related events occurred in 37 (21%) patients. Multivariate Cox proportional hazard analysis showed that the percentage predicted peak oxygen consumption, and oxygen uptake efficiency slope were independent predictors of cardiac-related events only in patients with a peak respiratory exchange ratio of ≥1.10. Sub-maximal exercise performance can be preserved in adult congenital heart disease patients. The percentage predicted oxygen consumption and the oxygen uptake efficiency slope are two independent predictors for short-term cardiac-related events in adult congenital heart disease patients.
峰值呼吸交换率是心肺运动试验中患者努力程度的客观标志物。我们评估了 175 例成人先天性心脏病患者的运动变量，以及呼吸交换率对运动变量短期心脏相关事件预后价值的影响。在 175 例患者中，110 例完成了峰值呼吸交换率≥1.10 的运动试验，其余 65 例的峰值呼吸交换率<1.10。与峰值呼吸交换率≥1.10 的患者相比，峰值呼吸交换率<1.10 的患者的峰值摄氧量、通气阈时摄氧量百分比、峰值心率、预计峰值心率百分比、双乘积、摄氧量效率斜率和运动振荡通气的患者数量明显减少。中位随访 21 个月后，37 例（21%）患者发生总心脏相关事件。多变量 Cox 比例风险分析显示，仅在峰值呼吸交换率≥1.10 的患者中，预计峰值摄氧量百分比和摄氧量效率斜率是心脏相关事件的独立预测因子。在成人先天性心脏病患者中，亚最大运动表现可以得到保留。预计摄氧量百分比和摄氧量效率斜率是成人先天性心脏病患者短期心脏相关事件的两个独立预测因子。
