부산대학교 도서관

In athletes, left atrial (LA) enlargement represents a physiological adaptation to exercise. 'Supranormal' diastolic function was demonstrated previously, but data on LA function are lacking. Our aim was to investigate the relation of the complex changes in LA deformation assessed by 2D speckle tracking echo and its relation with left ventricular (LV) diastolic properties in athletes.Methods: 40 subjects (20±4 years, 23 male) were enrolled: 20 endurance athletes and a control group of 20 age- and sex- matched sedentary subjects. LA geometry was assessed by volumes at the MVO (MVOV), MVC (MVCV), and at the beginning of the P wave (PV), while LA function by passive EF (pEF) as MVOV-PV/MVOV, expansion index (EIx) as MVOV-MVCV/MVOV, and active EF (aEF) as PV-MVCV/PV. LA deformation was measure by speckle tracking: contraction from peak negative strain (PNS) and strain rate (PNSR); relaxation from peak positive strain (PPS) and strain rate (PPSR), and global strain (GS). LV diastolic function was assessed by E/A ratio, flow propagation velocity (FPV), E/FPV, S/D (from pulmonary vein flow), long-axis early diastolic velocity (Eʼ), and E/Eʼ.Results: Athletes had 'supranormal' LV diastolic function (E/A=2.1±0.3 vs 1.4±0.2; FVP=76±12 vs 56±10 cm/s; E/FVP=1.4±0.6 vs 1.8±1.1; S/D= 0.8±0.1 vs 1.2±0.1; E/Eʼ=4.3±1.2 vs 6.2±2.1, all p<0.05). Concomitantly, there were complex changes in LA geometry and improved LA deformation in athletes (see table). Univariate analysis showed that GS was correlated positively with E, Eʼ and FPV (r=0.69; r=0.54; and r=0.52, all p<0.05) and negatively with E/Eʼ and S/D (r=-0.53 and r=-0.62, both p<0.01). By multiple stepwise regression analysis, best independent determinant of GS was E/Eʼ ratio (r=0.56, r2=0.42, p<0.01).Conclusion: Athletes had a “supranormal” LV diastolic function, related to better LA deformation. Assessment of complex changes in LA function by 2D speckle tracking echo may help to understand the role of LA in the cardiac adaptation induced by exercise training. It might also help to differentiate physiological from pathological cardiac hypertrophy.