Elliott Adrian D, Mahajan Rajiv, Linz Dominik, Stokes Michael, Verdicchio Christian V, Middeldorp Melissa E, La Gerche Andre, Lau Dennis H, Sanders Prashanthan
Centre for Heart Rhythm Disorders, South Australian Health & Medical Research Institute, University of Adelaide and Royal Adelaide Hospital, Adelaide, Australia.
Sports Cardiology Lab, Baker Heart and Diabetes Institute, Melbourne, Australia.
Clin Cardiol. 2018 Jun;41(6):843-848. doi: 10.1002/clc.22967. Epub 2018 Jun 12.
Atrial remodeling, vagal tone, and atrial ectopic triggers are suggested to contribute to increased incidence of atrial fibrillation (AF) in endurance athletes. How these parameters change with increased lifetime training hours is debated.
Atrial remodeling occurs in proportion to total training history, thus contributing to elevated risk of AF.
We recruited 99 recreational endurance athletes, subsequently grouped according to lifetime training hours, to undergo evaluation of atrial size, autonomic modulation, and atrial ectopy. Athletes were grouped by self-reported lifetime training hours: low (<3000 h), medium (3000-6000 h), and high (>6000 h). Left atrial (LA) volume, left ventricular (LV) dimensions, and LV systolic and diastolic function were assessed by echocardiography. We used 48-hour ambulatory electrocardiographic monitoring to determine heart rate, heart rate variability, premature atrial contractions, and premature ventricular contractions.
LA volume was significantly greater in the high (+5.1 mL/m , 95% CI: 1.3-8.9) and medium (+4.2 mL/m , 95% CI: 0.2-8.1) groups, compared with the low group. LA dilation was observed in 19.4%, 12.9%, and 0% of the high, medium, and low groups, respectively (P = 0.05). No differences were observed between groups for measures of LV dimensions or function. Minimum heart rate, parasympathetic tone expressed using heart rate variability indices, and premature atrial contraction and premature ventricular contraction frequencies did not differ between groups.
In recreational endurance athletes, increased lifetime training is associated with LA dilation in the absence of increased vagal parameters or atrial ectopy, which may promote incidence of AF in this cohort.
心房重构、迷走神经张力和房性异位触发因素被认为与耐力运动员心房颤动（AF）发病率增加有关。这些参数如何随一生训练时长增加而变化仍存在争议。
心房重构与总训练史成比例发生，从而导致AF风险升高。
我们招募了99名业余耐力运动员，随后根据一生训练时长进行分组，以评估心房大小、自主神经调节和房性早搏。运动员按自我报告的一生训练时长分组：低（<3000小时）、中（3000 - 6000小时）和高（>6000小时）。通过超声心动图评估左心房（LA）容积、左心室（LV）尺寸以及LV的收缩和舒张功能。我们使用48小时动态心电图监测来确定心率、心率变异性、房性早搏和室性早搏。
与低训练时长组相比，高训练时长组（+5.1 mL/m²，95%可信区间：1.3 - 8.9）和中训练时长组（+4.2 mL/m²，95%可信区间：0.2 - 8.1）的LA容积显著更大。高、中、低训练时长组中LA扩大的比例分别为19.4%、12.9%和0%（P = 0.05）。各组在LV尺寸或功能测量方面未观察到差异。各组之间的最低心率以及使用心率变异性指标表示的迷走神经张力、房性早搏和室性早搏频率没有差异。
在业余耐力运动员中，一生训练量增加与LA扩大相关，而迷走神经参数或房性异位未增加，这可能促使该队列中AF的发生。
