Center for Heart Rhythm Disorders, University of Adelaide and Royal Adelaide Hospital, Adelaide, Australia.
Center for Heart Rhythm Disorders, University of Adelaide and Royal Adelaide Hospital, Adelaide, Australia; Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
JACC Clin Electrophysiol. 2024 Jul;10(7 Pt 2):1608-1619. doi: 10.1016/j.jacep.2024.05.014. Epub 2024 May 16.
Reduced cardiorespiratory fitness (CRF) is an independent risk factor for the progression of atrial fibrillation (AF). We hypothesized that reduced CRF is associated with structural, functional, and electrical remodeling of the left atrium.
This study sought to correlate objectively assessed CRF with functional and electrical left atrial (LA) parameters using invasive and noninvasive assessments.
Consecutive patients with symptomatic AF undergoing catheter ablation were recruited. CRF was objectively quantified pre-ablation by using cardiopulmonary exercise testing. Using peak oxygen consumption, participants were classified as preserved CRF (>20 mL/kg/min) or reduced CRF (<20 mL/kg/min). LA stiffness was assessed invasively with hemodynamic monitoring and imaging during high-volume LA saline infusion. LA stiffness was calculated as ΔLA diameter/ΔLA pressure over the course of the infusion. LA function was assessed with echocardiographic measures of LA emptying fraction and LA strain. Electrical remodeling was assessed by using high-density electroanatomical maps for LA voltage and conduction.
In total, 100 participants were recruited; 43 had reduced CRF and 57 had preserved CRF. Patients with reduced CRF displayed elevated LA stiffness (P = 0.004), reduced LA emptying fraction (P = 0.006), and reduced LA reservoir strain (P < 0.001). Reduced CRF was also associated with reduced LA voltage (P = 0.039) with greater heterogeneity (P = 0.027) and conduction slowing (P = 0.04) with greater conduction heterogeneity (P = 0.02). On multivariable analysis, peak oxygen consumption was independently associated with LA stiffness (P = 0.003) and LA conduction velocities (P = 0.04).
Reduced CRF in patients with AF is independently associated with worse LA disease involving functional and electrical changes. Improving CRF may be a target for restoring LA function in AF.
心肺运动能力（CRF）降低是心房颤动（AF）进展的独立危险因素。我们假设，CRF 降低与左心房（LA）的结构、功能和电重构有关。
本研究旨在通过侵入性和非侵入性评估，将客观评估的 CRF 与功能性和电左房（LA）参数相关联。
连续招募因症状性 AF 而行导管消融术的患者。在消融前通过心肺运动测试客观地量化 CRF。根据最大耗氧量，将参与者分为 CRF 保留（>20 mL/kg/min）或 CRF 降低（<20 mL/kg/min）。通过大容量 LA 盐水输注期间的血流动力学监测和影像学评估，侵入性地评估 LA 僵硬度。LA 僵硬度通过输注过程中 ΔLA 直径/ΔLA 压力计算得出。通过 LA 排空分数和 LA 应变的超声心动图测量评估 LA 功能。通过 LA 电压和传导的高密度电解剖图评估电重构。
共招募了 100 名参与者，其中 43 名患者 CRF 降低，57 名患者 CRF 保留。CRF 降低的患者 LA 僵硬度升高（P=0.004），LA 排空分数降低（P=0.006），LA 储备应变降低（P<0.001）。CRF 降低也与 LA 电压降低（P=0.039）相关，LA 电压变异性更大（P=0.027），传导速度减慢（P=0.04），传导变异性更大（P=0.02）。多变量分析显示，最大耗氧量与 LA 僵硬度（P=0.003）和 LA 传导速度（P=0.04）独立相关。
AF 患者的 CRF 降低与涉及功能和电变化的更严重的 LA 疾病独立相关。提高 CRF 可能是恢复 AF 患者 LA 功能的目标。
