Division of Cardiology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.
Division of Cardiology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York; International Center for Health Outcomes and Innovation Research (InCHOIR), the Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, New York.
JACC Heart Fail. 2020 Apr;8(4):291-301. doi: 10.1016/j.jchf.2019.10.013. Epub 2020 Feb 6.
This study sought to characterize the hemodynamic response to exercise in LVAD-supported patients and identify parameters most strongly associated with peak oxygen consumption (VO).
Despite improved survival for heart failure patients afforded by continuous flow left ventricular assist devices (LVADs), peak exercise capacity remains impaired. Mechanisms underlying this reduced functional capacity remain poorly understood.
Patients referred for post-VAD hemodynamic optimization from December 2017 through June 2019 were enrolled. Swan Ganz catheters were inserted and upright incremental bicycle ergometry with respiratory gas analysis was performed. Hemodynamic measurements, mixed venous saturation, and arterial blood pressure were recorded every 3 min during exercise. Linear correlations were performed between peak VO (ml/min) and peak Fick cardiac output (CO), peak device flow, the assumed intrinsic CO derived as Fick CO-device flow, peak pressure differential across the LVAD (mean arterial pressure-pulmonary capillary wedge pressure), peak pressure differential across right ventricle (mean pulmonary artery pressure - right atrial pressure) and systemic vascular resistance.
Forty-five patients supported by axial flow pumps (n = 12) and centrifugal flow pumps (n = 33) were studied. There were 34 men and 11 women. Age averaged 60 ± 10 years. Peak VO averaged 10.6 ± 3.1 ml/kg/min. Fick CO had the greatest correlation with peak VO with r = 0.73 (p < 0.0001) followed by intrinsic CO (r = 0.67; p < 0.0001). Multivariate model that best predicted peak VO included Fick CO and peak arterial venous oxygen (AVO) difference.
LVAD supported patients have severely impaired peak exercise capacity. The peak Fick cardiac output was the best correlate of peak exercise performance.
本研究旨在描述左心室辅助装置（LVAD）支持患者运动时的血液动力学反应，并确定与峰值摄氧量（VO）最密切相关的参数。
尽管连续流动左心室辅助装置（LVAD）为心力衰竭患者提供了更好的生存机会，但峰值运动能力仍然受损。这种功能能力下降的机制仍知之甚少。
从 2017 年 12 月至 2019 年 6 月，招募了接受 LVAD 后血液动力学优化的患者。插入 Swan-Ganz 导管，并进行直立递增自行车测力计检查，同时进行呼吸气体分析。在运动过程中，每 3 分钟记录一次血液动力学测量、混合静脉饱和度和动脉血压。对峰值 VO（ml/min）与峰值 Fick 心输出量（CO）、峰值设备流量、假定的固有 CO（作为 Fick CO-设备流量）、LVAD 跨压差（平均动脉压-肺毛细血管楔压）、右心室跨压差（平均肺动脉压-右心房压）和全身血管阻力之间的峰值进行线性相关性分析。
研究了 45 名接受轴流泵（n=12）和离心流泵（n=33）支持的患者。有 34 名男性和 11 名女性。年龄平均为 60±10 岁。峰值 VO 平均为 10.6±3.1ml/kg/min。Fick CO 与峰值 VO 的相关性最强，r=0.73（p<0.0001），其次是固有 CO（r=0.67；p<0.0001）。最佳预测峰值 VO 的多元模型包括 Fick CO 和峰值动静脉氧差。
LVAD 支持的患者峰值运动能力严重受损。峰值 Fick 心输出量是峰值运动表现的最佳相关因素。
