Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
J Heart Lung Transplant. 2021 Jun;40(6):504-512. doi: 10.1016/j.healun.2021.02.005. Epub 2021 Feb 17.
Right ventricular (RV) contractile reserve shows promise as an indicator of occult RV dysfunction in pulmonary vascular disease. We investigated which measure of RV contractile reserve during exercise best predicts occult RV dysfunction and clinical outcomes.
We prospectively studied RV contractile reserve in 35 human subjects referred for right heart catheterization for known or suspected pulmonary hypertension. All underwent cardiac magnetic resonance imaging, echocardiography, and supine invasive cardiopulmonary exercise testing with concomitant RV pressure-volume catheterization. Event-free survival was prospectively adjudicated from time of right heart catheterization for a 4-year follow-up period.
RV contractile reserve during exercise, as measured by a positive change in end-systolic elastance (Ees) during exertion, was associated with elevation in pulmonary pressures but preservation of RV volumes. Lack of RV reserve, on the other hand, was tightly coupled with acute RV dilation during exertion (R = 0.76, p< 0.001). RV Ees and dilation changes each predicted resting RV-PA dysfunction. RV ejection fraction during exercise, which captured exertional changes in both RV Ees and RV dilation, proved to be a robust surrogate for RV contractile reserve. Reduced exercise RV ejection fraction best predicted occult RV dysfunction among a variety of resting and exercise RV measures, and was also associated with clinical worsening.
RV ejection fraction during exercise, as an index of RV contractile reserve, allows for excellent identification of occult RV dysfunction, more so than resting measures of RV function, and may predict clinical outcomes as well.
右心室（RV）收缩储备能力有望成为肺血管疾病隐匿性 RV 功能障碍的指标。我们研究了运动过程中 RV 收缩储备能力的哪种测量方法最能预测隐匿性 RV 功能障碍和临床结局。
我们前瞻性研究了 35 名因已知或疑似肺动脉高压而行右心导管检查的患者的 RV 收缩储备能力。所有患者均接受心脏磁共振成像、超声心动图和仰卧位侵入性心肺运动试验，同时进行 RV 压力-容积导管检查。前瞻性判定从右心导管检查开始的 4 年随访期间的无事件生存。
运动时 RV 收缩储备能力，通过运动时收缩末期弹性（Ees）的阳性变化来衡量，与肺动脉压升高有关，但 RV 容积保持不变。另一方面，缺乏 RV 储备能力与运动时 RV 急性扩张密切相关（R=0.76，p<0.001）。RV Ees 和扩张变化均预测静息 RV-PA 功能障碍。运动时 RV 射血分数，捕捉了 RV Ees 和 RV 扩张的运动变化，被证明是 RV 收缩储备能力的有力替代指标。运动时 RV 射血分数降低在各种静息和运动 RV 指标中最能预测隐匿性 RV 功能障碍，并且与临床恶化相关。
运动时 RV 射血分数作为 RV 收缩储备能力的指标，能够极好地识别隐匿性 RV 功能障碍，比静息 RV 功能测量更准确，并且可能预测临床结局。
