Department of Clinical Science, University of Bergen, Bergen, Norway.
British Heart Foundation Centre, King's College London, London, UK.
Eur Heart J Cardiovasc Imaging. 2021 May 10;22(6):650-657. doi: 10.1093/ehjci/jeaa154.
First-phase ejection fraction (EF1), the EF at the time to peak aortic jet velocity, has been proposed as a novel marker of peak systolic function in aortic stenosis (AS). This study aimed to explore the association of myocardial contractility and arterial load with EF1 in AS patients.
Data from a prospective, cross-sectional study of 114 patients with mild, moderate, and severe AS with preserved left ventricular EF (>50%) were analysed. EF1 was measured as the volume change from end-diastole to the time that corresponded to peak aortic jet velocity. Myocardial contractility was assessed by strain rate measured by speckle tracking echocardiography. Arterial stiffness was assessed by central pulse pressure/stroke volume index ratio (PP/SVi). The total study population included 48% women, median age was 73 years, and mean peak aortic jet velocity was 3.47 m/s. In univariable linear regression analyses, lower EF1 was associated with higher age, higher peak aortic jet velocity, lower global EF, lower global longitudinal strain, lower strain rate, and higher PP/SVi. There was no significant association between EF1 and heart rate or sex. In multivariable linear regression analysis, EF1 was associated with lower strain rate and higher PP/SVi, independent of AS severity. Replacing PP/SVi by valvular impedance did not change the results.
In patients with AS, reduced myocardial contractility and increased arterial load were associated with lower EF1 independent of the severity of valve stenosis.
第一时相射血分数(EF1),即峰值主动脉射流速度时的 EF,被提出作为主动脉瓣狭窄(AS)收缩期峰值功能的新标志物。本研究旨在探讨心肌收缩力和动脉负荷与 AS 患者 EF1 的相关性。
对 114 例左心室射血分数(EF)>50%的轻、中、重度 AS 患者前瞻性、横断面研究的数据进行了分析。EF1 被测量为从舒张末期到对应于峰值主动脉射流速度的时间的容积变化。心肌收缩力通过斑点追踪超声心动图测量的应变率来评估。动脉僵硬度通过中心脉搏压/每搏量指数比(PP/SVi)来评估。总研究人群包括 48%的女性,中位年龄为 73 岁,平均峰值主动脉射流速度为 3.47m/s。在单变量线性回归分析中,较低的 EF1 与较高的年龄、较高的峰值主动脉射流速度、较低的整体 EF、较低的整体纵向应变、较低的应变率和较高的 PP/SVi 相关。EF1 与心率或性别之间无显著相关性。在多变量线性回归分析中,EF1 与较低的应变率和较高的 PP/SVi 相关,独立于瓣膜狭窄的严重程度。用瓣膜阻抗替代 PP/SVi 并未改变结果。
在 AS 患者中,心肌收缩力降低和动脉负荷增加与 EF1 降低相关,与瓣膜狭窄的严重程度无关。