Department of Cardiology, Herlev-Gentofte Hospital, Copenhagen, Denmark.
Department of Cardiology, Alfred Hospital, Baker IDI Heart and Diabetes Research Institute, Melbourne, Australia.
Eur J Heart Fail. 2021 May;23(5):754-764. doi: 10.1002/ejhf.2146. Epub 2021 Mar 22.
A hallmark of heart failure with preserved ejection fraction (HFpEF) is impaired exercise capacity of varying severity. The main determinant of exercise capacity is cardiac output (CO), however little information is available about the relation between the constituents of CO - heart rate and stroke volume - and exercise capacity in HFpEF. We sought to determine if a heterogeneity in heart rate and stroke volume response to exercise exists in patients with HFpEF and describe possible clinical phenotypes associated with differences in these responses.
Data from two prospective trials of HFpEF (n = 108) and a study of healthy participants (n = 42) with invasive haemodynamic measurements during exercise were utilized. Differences in central haemodynamic responses were analysed with regression models. Chronotropic incompetence was present in 39-56% of patients with HFpEF and 3-56% of healthy participants depending on the definition used, but some (n = 47, 44%) had an increase in heart rate similar to that of healthy controls. Patients with HFpEF had a smaller increase in their stroke volume index (SVI) (HFpEF: +4 ± 10 mL/m , healthy participants: +24 ± 12 mL/m , P < 0.0001), indeed, SVI fell in 28% of patients at peak exercise. Higher body mass index and lower SVI at rest were associated with smaller increases in heart rate during exercise, whereas higher resting heart rate, and angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker use were associated with a greater increase in SVI in patients with HFpEF.
The haemodynamic response to exercise was very heterogeneous among patients with HFpEF, with chronotropic incompetence observed in up to 56%, and 28% had impaired increase in SVI. This suggests that haemodynamic exercise testing may be useful to identify which HFpEF patients may benefit from interventions targeting stroke volume and chronotropic response.
射血分数保留的心力衰竭（HFpEF）的一个标志是运动能力受损，严重程度不一。运动能力的主要决定因素是心输出量（CO），但关于 CO 的组成部分 - 心率和每搏量 - 与 HFpEF 患者运动能力之间的关系知之甚少。我们试图确定 HFpEF 患者的心率和每搏量对运动的反应是否存在异质性，并描述与这些反应差异相关的可能临床表型。
利用来自两项前瞻性 HFpEF 试验（n=108）的数据和一项健康参与者的研究（n=42），这些研究在运动期间进行了有创血流动力学测量。使用回归模型分析中心血流动力学反应的差异。根据使用的定义，HFpEF 患者中有 39-56%存在变时功能不全，而健康参与者中有 3-56%存在，但有些（n=47，44%）的心率增加与健康对照组相似。HFpEF 患者的每搏量指数（SVI）增加较小（HFpEF：+4±10mL/m，健康参与者：+24±12mL/m，P<0.0001），实际上，28%的患者在峰值运动时 SVI 下降。较高的体重指数和较低的静息 SVI 与运动中心率增加较小相关，而较高的静息心率和血管紧张素转换酶抑制剂/血管紧张素 II 受体阻滞剂的使用与 HFpEF 患者 SVI 的增加更大相关。
HFpEF 患者的运动时血流动力学反应非常异质，变时功能不全发生率高达 56%，28%的患者 SVI 增加受损。这表明血流动力学运动试验可能有助于识别哪些 HFpEF 患者可能受益于针对每搏量和变时反应的干预措施。
