Sixty-four healthy subjects were studied. LA ¦Å and SR were calculated with the reference point set at the P wave, which enabled the recognition of peak negative ¦Å (¦Åneg peak), peak positive ¦Å (¦Åpos peak), and the sum of those values, total LA ¦Å (¦Åtot), corresponding to LA contractile, conduit, and reservoir function, respectively. Similarly, peak negative SR (LA SRlate neg peak) during LA contraction, peak positive SR (LA SRpos peak) at the beginning of LV systole, and peak negative SR (LA SRearly neg peak) at the beginning of LV diastole were identified.
Global LA ¦Åpos peak, ¦Åneg peak, and ¦Åtot were 23.2 ¡À 6.7 % , ?4.6 ¡À 3.5 % , and 37.9 ¡À 7.6 % , respectively. Global LA SRpos peak, SRearly neg peak , and SRlate neg peak were 2.0 ¡À 0.6 s?, ?.0 ¡À 0.6 s?, and ?.3 ¡À 0.5 s?, respectively. The above-described variables derived from analysis of global LA ¦Å and LA SR correlated significantly with Doppler echocardiographic indexes that evaluated the same phase of the cardiac cycle or the same component of the LA function, including indexes derived from mitral inflow, pulmonary vein velocities, tissue Doppler, and LA volumes. Global LA ¦Åpos peak, LA ¦Åtot, and LA SRearly neg peak also correlated significantly with age or body mass index. Global LA SRlate neg peak also correlated significantly with age.
LA ¦Å analysis is a new tool that can be used to evaluate LA function. Further studies are warranted to determine the utility of LA ¦Å in disease states.