Atrial Remodeling, Autonomic Tone, and Lifetime Training Hours in Nonelite Athletes

doi:10.1016/j.amjcard.2011.03.086

The American Journal of Cardiology

Volume 108, Issue 4, 15 August 2011, Pages 580-585

https://doi.org/10.1016/j.amjcard.2011.03.086 Get rights and content

Endurance athletes have an increased risk of developing atrial fibrillation (AF) at 40 to 50 years of age. Signal-averaged P-wave analysis has been used for identifying patients at risk for AF. We evaluated the impact of lifetime training hours on signal-averaged P-wave duration and modifying factors. Nonelite men athletes scheduled to participate in the 2010 Grand Prix of Bern, a 10-mile race, were invited. Four hundred ninety-two marathon and nonmarathon runners applied for participation, 70 were randomly selected, and 60 entered the final analysis. Subjects were stratified according to their lifetime training hours (average endurance and strength training hours per week × 52 × training years) in low (<1,500 hours), medium (1,500 to 4,500 hours), and high (>4,500 hours) training groups. Mean age was 42 ± 7 years. From low to high training groups signal-averaged P-wave duration increased from 131 ± 6 to 142 ± 13 ms (p = 0.026), and left atrial volume increased from 24.8 ± 4.6 to 33.1 ± 6.2 ml/m² (p = 0.001). Parasympathetic tone expressed as root of the mean squared differences of successive normal-to-normal intervals increased from 34 ± 13 to 47 ± 16 ms (p = 0.002), and premature atrial contractions increased from 6.1 ± 7.4 to 10.8 ± 7.7 per 24 hours (p = 0.026). Left ventricular mass increased from 100.7 ± 9.0 to 117.1 ± 18.2 g/m² (p = 0.002). Left ventricular systolic and diastolic function and blood pressure at rest were normal in all athletes and showed no differences among training groups. Four athletes (6.7%) had a history of paroxysmal AF, as did 1 athlete in the medium training group and 3 athletes in the high training group (p = 0.252). In conclusion, in nonelite men athletes lifetime training hours are associated with prolongation of signal-averaged P-wave duration and an increase in left atrial volume. The altered left atrial substrate may facilitate occurrence of AF. Increased vagal tone and atrial ectopy may serve as modifying and triggering factors.

Section snippets

Methods

The Grand Prix of Bern is 1 of the most popular 10-mile races in Switzerland with >25,000 participants. Nonelite athletes were recruited by an open invitation letter published on the 2010 events homepage. All athletes applied by e-mail and provided age, endurance training years, and average endurance and strength training hours per week. Calculation of average training hours was based on athletes' estimation and/or exercise diary. Measurement of training years started in adulthood (≥18 years).

Results

Four hundred ninety-two men applied for participation and 70 were randomly selected. Ten runners had to be excluded (8 could not participate in the race because of muscular problems, 1 had mitral valve prolapse, and 1 had an undiagnosed arterial hypertension with diastolic dysfunction). Sixty runners entered the final analysis. Mean age was 42 ± 7 years. Thirty-eight runners (63%) participated in marathon events (1 to 30, mean 8 ± 7). Main type of exercise training was aerobic endurance

Discussion

Our study confirmed the results of previous investigations that endurance training is associated with left atrial enlargement.11, 13, 27 In addition, we showed a significant prolongation of signal-averaged P-wave duration in the high training group. For sedentary healthy men 40 years of age, mean signal-averaged P-wave durations of 117 to 122 ms have been published.18, 28 Patients with paroxysmal AF had mean P-wave durations of 145 ms.¹⁸ In our study, even the low and medium training groups had

Acknowledgment

The authors thank Max Burri, Alfred Dworzak, and Roger Steiner, MD, for their logistic support.

References (34)

R. Elosua et al.
Sport practice and the risk of lone atrial fibrillation: a case-control study
Int J Cardiol
(2006)
H. Heidbüchel et al.
Endurance sports is a risk factor for atrial fibrillation after ablation for atrial flutter
Int J Cardiol
(2006)
A. Aizer et al.
Relation of vigorous exercise to risk of atrial fibrillation
Am J Cardiol
(2009)
M. Wilhelm et al.
Early repolarization, left ventricular diastolic function, and left atrial size in professional soccer players
Am J Cardiol
(2010)
A. Pelliccia et al.
Prevalence and clinical significance of left atrial remodeling in competitive athletes
J Am Coll Cardiol
(2005)
A. Pelliccia et al.
Long-term clinical consequences of intense, uninterrupted endurance training in Olympic athletes
J Am Coll Cardiol
(2010)
P.S. Chen et al.
Autonomic nerve activity and atrial fibrillation
Heart Rhythm
(2007)
J. Karjalainen et al.
Lone atrial fibrillation in vigorously exercising middle aged men: case–control study
BMJ
(1998)
L. Mont et al.
Long-lasting sport practice and lone atrial fibrillation
Eur Heart J
(2002)
J. Hoogsteen et al.
Paroxysmal atrial fibrillation in male endurance athletesA 9-year follow up
Europace
(2004)

L. Molina et al.

Long-term endurance sport practice increases the incidence of lone atrial fibrillation in men: a follow-up study

Europace

(2008)

L. Mont et al.

Physical activity, height, and left atrial size are independent risk factors for lone atrial fibrillation in middle-aged healthy individuals

Europace

(2008)

L. Mont et al.

Endurance sport practice as a risk factor for atrial fibrillation and atrial flutter

Europace

(2009)

J. Grimsmo et al.

High prevalence of atrial fibrillation in long-term endurance cross-country skiers: echocardiographic findings and possible predictors—a 28–30 years follow-up study

Eur J Cardiovasc Prev Rehabil

(2010)

B. Benito et al.

Cardiac arrhythmogenic remodeling in a rat model of long-term intensive exercise training

Circulation

(2011)

M. Fukunami et al.

Detection of patients at risk for paroxysmal atrial fibrillation during sinus rhythm by P wave-triggered signal-averaged electrocardiogram

Circulation

(1991)

Y. Abe et al.

Prediction of transition to chronic atrial fibrillation in patients with paroxysmal atrial fibrillation by signal-averaged electrocardiography: a prospective study

Circulation

(1997)

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Citation Excerpt :
This hypothesis was based on animal models, where high-intensity exercise induced fibrosis in the atria, but not in the left ventricle [50]. Human studies have confirmed that vigorous PA leads to left atrial dilation [51–53]. However, as it was recently highlighted by Chen et al., it seems that there is a PA cutoff of until which atrial enlargement is not accompanied by pathological processes such as inflammation, oxidative stress, myolysis, fibrosis and reduced capillary density [54].
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MiscellaneousAtrial Remodeling, Autonomic Tone, and Lifetime Training Hours in Nonelite Athletes

Section snippets

Methods

Results

Discussion

Acknowledgment

Int J Cardiol

Int J Cardiol

Am J Cardiol

Am J Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

Heart Rhythm

Lone atrial fibrillation in vigorously exercising middle aged men: case–control study

BMJ

Long-lasting sport practice and lone atrial fibrillation

Eur Heart J

Paroxysmal atrial fibrillation in male endurance athletesA 9-year follow up

Europace

Long-term endurance sport practice increases the incidence of lone atrial fibrillation in men: a follow-up study

Europace

Physical activity, height, and left atrial size are independent risk factors for lone atrial fibrillation in middle-aged healthy individuals

Europace

Endurance sport practice as a risk factor for atrial fibrillation and atrial flutter

Europace

High prevalence of atrial fibrillation in long-term endurance cross-country skiers: echocardiographic findings and possible predictors—a 28–30 years follow-up study

Eur J Cardiovasc Prev Rehabil

Cardiac arrhythmogenic remodeling in a rat model of long-term intensive exercise training

Circulation

Detection of patients at risk for paroxysmal atrial fibrillation during sinus rhythm by P wave-triggered signal-averaged electrocardiogram

Circulation

Prediction of transition to chronic atrial fibrillation in patients with paroxysmal atrial fibrillation by signal-averaged electrocardiography: a prospective study

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Miscellaneous
Atrial Remodeling, Autonomic Tone, and Lifetime Training Hours in Nonelite Athletes