Exercise for Cardiovascular Disease Prevention and Treatment From Molecular to Clinical, Part 1

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[ 36 , 37 ]. They have been also applied to the study of LA remodeling in athletes. The

aim of this technique is to distinguish the LA adaptation secondary to left ventricu-

lar hypertrophy due to the exercise from pathologic cardiac remodeling due to arte-

rial hypertension, diabete or cardiac valvular diseases.

In a cohort study of 1300 elite athletes, it was observed a prevalence of LA ECG

abnormality (expressed by P-wave duration more than 120 msec in I or II leads with

a negative deflession of the P-wave greater than or equal to 1 mm in depth and

40 msec in duration in V1 lead) in 1.2% of endurance athletes and in 0.5% of non-

endurance athletes, respectively [ 31 ]. The presence of this abnormality requires a

further investigation with echocardiography.

By using 2D echocardiography, the LA size should be measured at the end of

ventricular systole, when it reaches its greater dimension. The easier method to

evaluate the LA dimension is the measurement of the antero-posterior diameter (in

the parasternal long axis view), the longitudinal and the trasverse diameter (in apical

four chamber view) [ 38 ]. Linear dimension are simple to obtain but considered

inaccurate, so measurement of volume rather than linear dimension or area is pre-

ferred [ 38 , 39 ]. Measurements of LA volume (LAV) is obtained by ellipsoid model

and Simpson method, measuring the LA area and the longitudinal diameter in apical

four-chamber and apical two-chamber views [ 38 ].

LAV should be indexed for the BSA to obtain the Left Atrial Volume indexed

(LAVi) [ 33 ]. The cut-off to define LA enlargement is established to 34 mL/m^2 as

indicated in the ASE/EAE guidelines [ 2 , 38 ]. Anyway this cut-off has been calcu-

lated on a large non-athlete population.

Pelliccia et al. conducted a large study on 1777 competitive athletes and found a

small increase of LA antero-posterior diameter(≥40 mm) in 18% of athletes and a

greater dilatation (≥ 45 mm) in 2%, that was proportional to the LV cavity enlarge-

ment. As the 20% of athletes have a dilatation, it means that a mild enlargement is a

physiologic adaptation to exercise [ 39 ]. For this reason, it was established the upper

limit to 45 mm in female and 50 mm in male athletes to define LA enlargement

evaluated with the linear method [ 2 , 39 ] (Table 2.3). Regards to the LAVi dimen-

Table 2.3 Athlete’s left atrial morphological and functional parameters

Authors

Number of

athletes Type of exercise Parameter

Mean

value

Upper

value

Pelliccia et al.

[ 39 ]

1777 Endurance or

power

LA diameter (male)

(mm)

37 50

LA diameter

(female) (mm)

32 45

D’Andrea et al.

[ 40 ]

615 Endurance or

power

LA volume index

(male)(ml/m^2 )

28 36

LA volume index

(female) (ml/m^2 )

26.5 33

D’Andrea et al.

[ 43 ]

80 Power LA strain (%) 50 80

A. D’Andrea et al.