Cardiology Department, Hospital General Universitari de Castelló, Universitat Jaume I, Castellón, Spain.
Cardiology Department, Hospital Clínico Universitario de Valencia, INCLIVA, Universitat de València, Spain.
ESC Heart Fail. 2018 Aug;5(4):579-585. doi: 10.1002/ehf2.12281. Epub 2018 Mar 24.
The mechanisms of exercise intolerance in heart failure with preserved ejection fraction (HFpEF) are not yet elucidated. Chronotropic incompetence has emerged as a potential mechanism. We aimed to evaluate whether heart rate (HR) response to exercise is associated to functional capacity in patients with symptomatic HFpEF.
We prospectively studied 74 HFpEF patients [35.1% New York Heart Association Class III, 53% female, age (mean ± standard deviation) 72.5 ± 9.1 years, and 59.5% atrial fibrillation]. Functional performance was assessed by peak oxygen consumption (peak VO ). The mean (standard deviation) peak VO was 10 ± 2.8 mL/min/kg. The following chronotropic parameters were calculated: Delta-HR (HR at peak exercise - HR at rest), chronotropic index (CI) = (HR at peak exercise - resting HR)/[(220 - age) - resting HR], and CI according to the equation developed by Keteyian et al. (CIK) (HR at peak exercise - HR at rest)/[119 + (HR at rest/2) - (age/2) - 5 - HR at rest]. In a bivariate setting, peak VO was positively and significantly correlated with Delta-HR (r = 0.35, P = 0.003), CI (r = 0.27, P = 0.022), CIK (r = 0.28, P = 0.018), and borderline with HR at peak exercise (r = 0.22, P = 0.055). In a multivariable linear regression analysis that included clinical, analytical, echocardiographic, and functional capacity covariates, the chronotropic parameters were positively associated with peak VO . We found a linear relationship between Delta-HR and peak VO (β coefficient of 0.03; 95% confidence interval: 0.004-0.05; P = 0.030); conversely, the association among CIs and peak VO was exponentially shaped.
In patients with chronic HFpEF, the HR response to exercise was positively associated to patient's functional capacity.
射血分数保留的心力衰竭（HFpEF）运动不耐受的机制尚未阐明。变时性功能不全已成为潜在的机制。我们旨在评估 HFpEF 患者的心率（HR）对运动的反应与功能能力是否相关。
我们前瞻性研究了 74 例 HFpEF 患者[35.1%纽约心脏协会（NYHA）心功能分级 III 级，53%女性，年龄（均值±标准差）72.5±9.1 岁，59.5%心房颤动]。功能表现通过峰值耗氧量（peak VO ）评估。平均（标准差）peak VO 为 10±2.8 mL/min/kg。计算了以下变时性参数：Delta-HR（运动峰值时的 HR-休息时的 HR）、变时指数（CI）=（运动峰值时的 HR-休息时的 HR）/[（220-年龄）-休息时的 HR]，以及根据 Keteyian 等人开发的方程计算的 CI（CIK）（运动峰值时的 HR-休息时的 HR）/[119+（休息时的 HR/2）-（年龄/2）-5-休息时的 HR]。在双变量设定中，peak VO 与 Delta-HR（r=0.35，P=0.003）、CI（r=0.27，P=0.022）、CIK（r=0.28，P=0.018）呈正相关，与运动峰值时的 HR 呈边缘相关（r=0.22，P=0.055）。在包括临床、分析、超声心动图和功能能力的多变量线性回归分析中，变时性参数与 peak VO 呈正相关。我们发现 Delta-HR 与 peak VO 之间存在线性关系（β系数为 0.03；95%置信区间：0.004-0.05；P=0.030）；相反，CI 与 peak VO 之间的关系呈指数形。
在慢性 HFpEF 患者中，HR 对运动的反应与患者的功能能力呈正相关。
