Role of echocardiography on early diagnosis of atrial remodelling and fibrosis in elite athletes.

There is emerging data indicating that long-standing vigorous exercise may be associated with atrial structural remodelling. This remodelling process is may be the cause of the increasing frequency of atrial arrythmias in athletes. Early diagnosis of atrial remodelling by atrial imaging could have a role in management of atrial arrythmias in elite athletes. In this study we aimed to diagnose early phases of atrial remodelling in elite athletes. Two groups of athletes including professional weight lifters (n = 33), professional marathoners (n = 32) and sedentary participants (n = 30) were enrolled. We also studied patients who received cardiotoxic chemotherapy (n = 10) for comparison. Serum TGF-beta level as a marker of fibrosis was measured. Both left atrial (LA) 3D volume and strain values were analysed. There was a positive correlation between serum TGF-beta levels and LA volumes and negative correlation between TGF-beta levels and strain values. TGF-beta levels were higher among chemotherapy and weight lifter groups, compared to control and marathoner groups [mean 0.57 ± 0.3 and 0.55 ± 0.2 vs. 0.45 ± 0.2 and 0.47 ± 0.2, respectively, p = 0.005]. LA volumes were higher among chemotherapy and weight lifter groups [median 33 (26-38) and 31 (23-36) respectively, p = 0.005], and strain values were lower in these two groups [mean 20.3 ± 2.5 and 24.6 ± 4.5, respectively, p < 0.005] compared to control and marathoner groups. Total exercise volume was higher in weight lifter group compared to marathoners [13,780 (2496-36,400) vs. 4732 (780-44928), respectively, p = 0.001]. There wasn't any difference between any group regarding left ventricular systolic and diastolic functions. Vigorous exercise causes atrial remodelling and fibrosis in elite athletes. Strength exercise carries higher risk for atrial fibrosis than endurance exercise. Burden of exercise is correlated with the severity of cardiac fibrosis. Echocardiographic evaluation of the left atrium and TGF-beta levels may help to detect subclinical cardiac remodelling and fibrosis.