Sex-specific differences in bi-atrial strain in elite athletes: results from the ELITE cohort
Authors: Daems J J N , Van Hattum J C , Verwijs S M , Van Der Hoeven F M A , Van Diepen M A , De Bruin - Bon H A C M , Vleugels J , Bombeld D C M , Bouma B J , Moen M H , Groenink M , Pinto Y M , Jorstad H T 
Published: November 2023

Abstract

Background
Athletes frequently demonstrate increased atrial volumes as a result of physiological adaptation to sports. In the general population, atrial dilatation is associated with decreased atrial function, measured as atrial ejection fraction and strain. However, studies on bi-atrial function in athletes have been limited and have primarily focused on male endurance athletes.

Purpose
To determine sex-specific differences in left- and right atrial strain in elite athletes.

Methods
The study population consisted of elite athletes included in the ELITE-cohort older than 16 years of age and exercising ≥10 hours per week and competing at the highest national, international or Olympic level in the Netherlands. All included athletes underwent a standardised resting transthoracic echocardiogram. Left- and right atrial (LA/RA) reservoir-, conduit- and cntractile- strain were measured with grey-scale-based 2D Speckle tracking software in the four- and two-chamber views and bi-atrial volume and function parameters were collected.

Results
A total of 166 elite athletes were included (48.2% female, media age 25 years [22, 28]), with athletic disciplines road cycling 25.3%, hockey 16.9%, rowing 14.5%, soccer 12.7%, water polo 9.6%, sailing 6.0%, track cycling 3.6%, and other 11.6%. There were no sex differences in age and training hours (18 hours per week). Athletic disciplines were evenly distributed among female- and male athletes. Female athletes had a lower BSA than male athletes (1.8 cm2 [1.7, 1.9] vs 2.1 cm2 [1.9, 2.2], p &lt;0.001). Female athletes had similar LAESVi (36.5 ml/cm2 [32.0, 42.0] vs 36.5 ml/cm2 [31.0, 47.8]) and LAESAi (11.2 cm2/m2 [9.5, 12.2] vs 10.6 cm2/m2 [9.0, 11.9]) compared with male athletes. Female athletes had a higher LAEF (63.2 ±6.2% vs 60.7 ±5.8%, p =0.007) and greater LA deformation than male elite athletes during the reservoir- (34.7 ±6.2% vs 31.4 ±4.9%, p &lt;0.001) and conduit phase (-25.2 ±5.2% vs -22.6 ±3.7% p &lt;0.001). LA deformation during the contractile phase (-9.0% [-12.0, -7.0] vs – 9.0% [-11,-7]) was similar (figure 1). Female athletes had a lower RAESVi (29.5 ml/m2 [25.2, 36.4] vs 35.3 ml/m2 [28.5, 41.9], p &lt;0.01) but there were no differences in RAEF (42.6 ±10.3% vs 45.2 ±11.1%) and RAESAi (9.8cm2/m2 [8.8, 11.3] vs 10.1 cm2/m2 [8.8-11.3]). There were no differences in RA reservoir- (30.7 ±7.6% vs 29.4 ±8.0%), conduit (-21.4 ±6.6% vs -20 ±6.6%) and contractile strain (-9.0% [-11.0, -6.8] vs -9.0% [-11.8, -7.0]) (figure 2).

Conclusion
In both male and female elite athletes, the LA is of comparable area and volume. However, in female athletes LA deformation is greater during the reservoir and conduit phases, resulting in a greater LA ejection fraction in the presence of similar LA contractile deformation. Conversely, RA volumes were smaller in female athletes, but deformation was similar compared with male athletes. Our findings suggest the presence of sex-specific atrial exercised-induced adaptation.Figure 1.Figure 2.